Hydroxylation-Inducing the Coupled Dual-Centers in Highly Amorphized Ni0.76Mo1.24/Mo2N Nanoarrays with Superior Alkaline Hydrogen Evolution

Hydroxylation-Inducing the Coupled Dual-Centers in Highly Amorphized Ni0.76Mo1.24/Mo2N Nanoarrays with Superior Alkaline Hydrogen Evolution | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Hydroxylation-Inducing the Coupled Dual-Centers in Highly Amorphized Ni 0.76 Mo 1.24 /Mo 2 N Nanoarrays with Superior Alkaline Hydrogen Evolution Huanli Jia, Haiyan Wang, Xiaofang Su, Hucheng Zhang, Fangfang Yan, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2441531/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The site-blocking effect (SBE) of nonelectro-chemical steps (nonECS) gives the sluggish kinetics in alkaline hydrogen evolution reaction (HER), but remains rather challenging in electrocatalysis. Herein, we explored nonECS on the highly amorphized NiMoN/NC(500-R) nanoarrays, in which Ni 0.76 Mo 1.24 and Mo 2 N with the crystallinity of only 13.3% were embedded into nitrogen-rich derived carbons (NC) at 500 o C, then followed by electrochemical surface reconstruction. The amorphization and hydroxylation induce the coupled dual-centers of Ni-Mo species to circumvent SBE through separating H*- and H 2 -involved elementary steps from nonECS, and deliver efficient transfer of individual species and heavy charge accumulation to actuate the whole HER. Resultantly, the exceptional catalytic activity is demonstrated by ultra-low overpotentials of 5.8 and 200.6mV at 10 and 1000mA cm -2 , respectively. Importantly, NiMoN/NC(500-R) survive in lasting alkaline HER for 50 days at 500mA cm -2 almost without degeneration. This work presents the key to get rid of SBE in electrocatalysis, and the inspiration to rationally design the amorphized nanoarrays of electrocatalysts. Physical sciences/Chemistry/Electrochemistry/Electrocatalysis Physical sciences/Materials science/Materials for energy and catalysis/Electrocatalysis Physical sciences/Engineering/Chemical engineering Physical sciences/Materials science/Nanoscale materials/Structural properties Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction The increasing environmental concerns have motivated great interest in hydrogen energy that has high gravimetric energy density, earth abundance and wide applications without emitting pollutants. 1 – 4 Currently, hydrogen evolution reaction (HER) from water has been recognized as the most promising technique of sustainable production as powered by clean electricity. However, the renewable grid supply-fluctuation of photovoltaics, wave and wind energies is imposed by spatial, temporal, climatic and seasonal factors. Therefore, the real-time conversion of these energies requires HER electrocatalysts that respond sensitively to the dynamical input power, and operate competently over a wide current-density range and long-term durability. 5 – 7 Acidic HER usually is two to three orders of magnitude faster than alkaline HER, 8 , 9 but the vulnerable metal-based catalysts and proton exchange membrane in acidic solutions make large-scale hydrogen production to prefer in alkaline media. 10 , 11 Therefrom, the low-cost transition metal-based catalysts are intensively exploited to minimize HER barriers. 12 – 18 Unfortunately, sluggish kinetics on the electrocatalysts incurs high overpotentials, and becomes particularly worse at industrial current densities (≥ 500 mA cm − 2 ). 19,20 Currently, an effective strategy has been developed by vertically growing transition metal-based nanoarrays (NAs) on metal substrates, and the resultant monolithic catalysts are brought about smooth mass transfer and negligible interface electric-resistances, improving significantly in catalytic efficiency. 21 – 27 However, the NAs have high crystallinity with mechanical rigidity, industrially, are difficult to bear massive H 2 release. Although amorphization imparts catalysts with rich active sites, flexible architectures, desirable catalytic activity and durability, 28 – 33 the amorphized NAs incline to geometrically collapse to increase charge and mass transfer barriers, and are not considered in previous literature. Alkaline HER is launched from Volmer reaction, and followed by Heyrovsky or Tafel reaction (Scheme S1). 34 , 35 The reaction rate is controlled by electrochemical steps and concomitant nonelectrochemical steps (nonECS). The electrochemical steps involve in electron transfer in H 2 O dissociation and concerted proton-electron transfer, and the nonECS embrace adsorption/diffusion of H 2 O, H*, H 2 and OH − . nonECS are directly related to site-blocking effect (SBE), and play the governed roles as the electron transfers are not rate-determining step (RDS). To circumvent SBE, ideally, we should decouple nonECS through integrating a site to catalyze Volmer reaction with another to catalyze Heyrovsky or Tafel reaction. Moreover, the separated elementary steps lower the whole reaction barrier more on the coupled dual-center electrocatalysts than on single active site, and give higher catalytic efficiencies. In fact, the electrocatalysis are designed rarely following the synergistic dual-center motivation to separately study multiple nonECS, and commonly is measured by HER activity with balancing H*, H 2 O and OH − interactions in single site. The key challenge lies in the coupled dual-center electrocatalysts requires enough partitioning spaces and favorable electronic structures to suppress SBE and recombination of H* with OH − in HER. Here, we report the hydroxylation-conditioning nonECS to affect HER kinetics as revealed by density functional theory (DFT) calculations, pulse voltammetry, and operando electrochemical impedance spectroscopy (EIS). The crystalline NiMoO 4 arrays on nickel foam (NF) were nitrogenized by ionic liquid (IL) of 1-ethyl-3-methylimidazolium tetrazolate ([C 2 mim][Tet], Scheme S2) at 500 o C, and the resultant highly amorphized NAs are embedded with Mo 2 N and Ni 0.76 Mo 1.24 in the skeleton of IL-derived nitrogen-rich carbons (NC). Subsequently, the Ni species are fully hydroxylated by the electrochemical surface reconstruction (ESRC) to harvest NiMoN/NC(500-R) NAs. It is demonstrated that the 3D self-supported architecture gives robust durability, efficient mass and charge transfer. Attractively, the amorphization and hydroxylation induce the super-large electrochemical surface area (ECSA), and create the active dual-centers to separate H*- and H 2 -involved elementary steps from H 2 O- and OH*-involved nonECS in NiMoN/NC(500-R) NAs. Thereby, the chemical coupling of Mo with Ni species provides the cooperative arenas for different nonECS, and significantly alleviate SBE to achieve the unexpected catalytic activity in alkaline HER. Results Microstructural feature and surface hydroxylation. The highly amorphized NiMoN/NC(500) NAs were synthesized by IL nitridation to split NiMoO 4 ·xH 2 O cuboid arrays (Fig. 1 A). NiMoO 4 ·xH 2 O nanorods with smooth surfaces have the average radial size of 0.54µm as shown in scanning electron microscopy (SEM) images (Figure S1). After the aqueous solution of IL was uniformly coated on the hydrophilic surfaces, the thermal nitridation at 500°C converts NiMoO 4 ·xH 2 O to NiMoN/NC(500) NAs. The chemical conversion doesn’t alter the array morphology, but split the nanorods to slenderer ones with an average radial size of 0.18µm (Fig. 1 B). Subsequently, NiMoN/NC(500) was activated by ESRC with 100 circles of cyclic voltammetry (CV) between 1.4~-0.4V vs. RHE in 1M KOH, and the resultant NiMoN/NC(500-R) presents a little blurrier appearances owing to the surface hydroxylation (Fig. 1 C). 36 As shown by scanning transmission electron microscopy (STEM) image, the nanorod from NiMoN/NC(500-R) NAs is built by the closely packed nanoparticles (Fig. 1 D), and renders the electrocatalyst with the fully expanded ECSA. The phase interfaces are identified by the lattice spaces of 0.240 and 0.209 nm that are respectively indexed to (111) and (114) planes of Mo 2 N and Ni 0.76 Mo 1.24 in high-resolution TEM (Fig. 1 E). The paragenesis of Mo 2 N and Ni 0.76 Mo 1.24 is further evidenced by their spots/circles in selected electron area diffraction (SAED) patterns (Fig. 1 F). Moreover, the angle annular dark field (HAADF)-STEM image and energy dispersive X-ray spectroscopy (EDS) mapping images verify the homogeneous element distributions over the nanorod, and imply that Mo and Ni species are embedded into NC (Fig. 1 G ~ L). Instead of simple chemical digestion, interestingly, the thermal nitridation of IL split nanorods into slimmer ones, and simultaneously the arrays are well maintained in NiMoN/NC(500). The fact is clarified by the morphologic evolutions with IL loadings on NiMoO 4 ·xH 2 O arrays (Figure S2). As calcined at 500°C, IL of 25mg chemically modifies NiMoO 4 nanorods to present rough surfaces. Increasing IL to 50mg, the most of nanorods are axially hollowed out, and some are split into finer ones. If introducing 200mg IL, the nanorods interconnect one another to give the 3D mesoporous network. It is the optimized IL loading of 100mg that renders NiMoN/NC(500) with the finest NAs and the fully exposed active sites. The crystalline-phases and crystallinity are analyzed by X-ray diffraction (XRD) patterns. Except the incomplete conversion of NiMoO 4 ·xH 2 O at 400°C (Figure S3), as comparison, we synthesized Ni 3 Mo 3 N/NC(600) and Mo 2 C/NC(700) NAs respectively at 600 and 700°C, following the similar procedures for NiMoN/NC(500). Combining the analyses on their powders without NF interferences (Figure S4), the crystalline phases are Mo 2 N and Ni 0.76 Mo 1.24 in NiMoN/NC(500) (Fig. 2 A), Ni 3 Mo 3 N in Ni 3 Mo 3 N/NC(600), and Ni 3 Mo 3 N and β-Mo 2 C in Mo 2 C/NC(700) (Figure S5). As subjected to ESRC, the XRD patterns are not altered in NiMoN/NC(500-R) and Ni 3 Mo 3 N/NC(600-R), whereas the Ni 3 Mo 3 N diffractions disappear in Mo 2 C/NC(700-R). The disintegration of crystalline Ni 3 Mo 3 N is verified by the more amorphous appearances of Mo 2 C/NC(700-R) than the other samples (Figure S6). Noticeably, the most broadened diffraction profiles imply the highly dispersed crystalline-phases in NiMoN/NC(500-R). Reference to the (221) diffraction of Ni 3 Mo 3 N in Ni 3 Mo 3 N/NC(600), quantitatively, the relative crystallinity of NiMoN/NC (500-R) is evaluated to be only 13.3% by the full width of half maximum of (111) diffraction of Mo 2 N (Figure S7). Despite of the very low χ C , NiMoN/NC(500-R) is most antioxidative in air even under high temperature owing to the profound surface hydroxylation (Figure S8) as shown by linear sweep voltamogram (LSV) of oxygen evolution reaction (OER) and X-ray photoelectron spectroscopy (XPS) analysis later. In Raman spectra, moreover, the disappearances of bending (344.9 cm − 1 ) and stretching (940.8 cm − 1 ) vibrations of Mo-O 37 , 38 give the additional proof of NiMoO 4 ·xH 2 O conversions (Fig. 2 B, Figure S9), and the D and G bands indicate IL-derived carbons from the pyrolysis of IL. 39 The metal element contents hold almost unchanged in these electrocatalysts from the analyses of inductively coupled plasma source mass spectrometer and survey scans of XPS (Figure S10, Table S1). Obviously, the self-supporting NiMoN/NC(500-R) NAs were mainly constructed by integrating NC with highly amorphized Mo 2 N and Ni 0.76 Mo 1.24 together. Ni 2+ (Ni(OH) 2−δ )/Ni 3+ (NiOOH) oxidation peak indicates the electrooxidation in Ni-based catalysts in OER, 40 , 41 and is altered by surface hydroxylation. At 10mA cm − 2 in LSV, the potential increases from 1.317V for NiMoN/NC(500) to 1.349V for NiMoN/NC(500-R) (Fig. 2 C). The increment of 32mV is ascribed to higher barrier of surface oxidation, and implies that the electrooxidation is deactivated by ESRC owing to deepening hydroxylation. Comparatively, the oxidation potential of Ni 2+ at 10mA cm − 2 in Ni 3 Mo 3 N/NC(600-R) is 21mV more than in Ni 3 Mo 3 N/NC(600), and is almost same in Mo 2 C/NC(700) and Mo 2 C/NC(700-R) (Figure S11). Hence, the surfaces of NiMoN/NC(500-R) are profoundly hydroxylated by ESRC, Ni 3 Mo 3 N/NC(600-R) moderately, and Mo 2 C/NC(700-R) weakly. The surface hydroxylation is further clarified by the dominant OH species from high-resolution XPS of O 1s in three post-electrcatalysts (Figure S12). 42 Except C-metal species, the binding energies of each species are same in the deconvoluted O1s, N1s, C1s spectra before and after ESRC (Figure S12-S14), 43 – 46 implying that the nonmetal elements situate in similar chemical surroundings and are not the crucial factors to raise distinct catalytic activities. As active Ni-Mo species, their surface valence states depend heavily on annealing temperature, and evolve with ESRC to achieve favorable electronic structures for HER. As compared with three pre-catalysts (Figure S15), all post-catalysts indicate the enhanced signals of Ni-O species but the weakened ones of Ni-Mo and Ni 0 37,43,47 owing to ESRC hydroxylation (Fig. 2 D). Distinctively, the disintegration of crystalline Ni 3 Mo 3 N in Mo 2 C/NC(700-R), consistent with XRD result, is verified by the almost disappearing peak of Ni 0 /Ni-Mo, and suggests the hydroxylation largely destructs the chemical bonding and coupling of Ni with Mo atoms. Evidently, the three post-catalysts represent the same valence states of Ni 0 /Ni-Mo, but NiMoN/NC(500-R) has the binding energy of Ni-O that are 0.3eV lower than Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R), and are more nucleophilic to support the spilled H*. Furthermore, Mo-N and Mo-C species are derived from the chemical combination of Mo element with NC. Mo-C species is not detected in NiMoN/NC(500-R), but present in Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R) that respectively give the binding energies of 0.5 and 0.8 eV lower than Mo-N (Fig. 2 E). As transferred to measuring system, the deconvoluted peaks of Mo 4+ and Mo 6+ indicate that Mo species in catalyst surfaces are readily oxidized by air, 43 , 48 and the oxidized Mo sites are more electrophilic to adsorb water. Therefore, the catalytic dual-centers from Ni-Mo bonding are constructed by coupling of the partially oxidized Mo species with the fully hydroxylated Ni species. Considering the crystalline-phases, reasonably, the coupled dual-centers of Ni-Mo species are most abundant on the highly amorphized NiMoN/NC(500-R), moderate on the crystalline Ni 3 Mo 3 N/NC(600-R), and almost absent on Mo 2 C/NC(700-R) without Ni-Mo bonding. Evidently, the surface-hydroxylation is necessary to induce the coupled dual-centers to circumvent SBE of onoECS, and is analyzed by the adsorption thermodynamics from DFT-calculations with the structural models (Figure S16). The nonECS in HER involves mainly with the adsorption of H 2 O and H* along with desorption of OH* and H 2 (Fig. 3 A). The Gibbs free energy (ΔG H2O ) indicates the Mo site presents the strongest adsorption (Fig. 3 B), whereas the adsorbed H 2 O on Ni site is undesirable on dual-center HONiMoN (Figure S17). Comparatively, a slightly exothermal process is implied by the similar small ΔG H2O on Mo and Ni sites of NiMoN. Once the adsorbed H 2 O is dissociated by the applied bias, OH* is left behind on Mo site, and the concomitant H* spills over the catalysts. Therein, OH* desorption from HONiMoN into bulk is thermodynamically most favorable as suggested by the positive ΔG OH* of 0.17eV (Fig. 3 B). Moreover, |ΔG H* | of the spilled H* on Ni site of HONiMoN give the most reasonable value of 0.15 eV close to zero, and the optimal energy barrier for H* adsorption and H 2 desorption (Fig. 3 C). By contrast, ΔG H2O , ΔG OH* and |ΔG H* | in HOONiMoN respectively indicate the thermodynamically unfavourable adsorption/desorption in HER (Fig. 3 B and Figure S18), and clarify that the NiOOH with high valence state, instead of Ni-OH, impairs the catalytic activity. Consistent with XPS analyses, the nonmetallic O atoms are not dominant factors to affect the catalytic activities. Thereby, the coupled dual-centers are induced by hydroxylation, and each center performs its own functions to circumvent SBE and alleviate recombination of H* with OH - on HER catalysts. Electrocatalysis In Hydrogen Evolution The electrocatalytic activities are evaluated by LSVs with 90% iR-compensation in 1M KOH, and the commercial Pt/C was employed for comparison (Fig. 4 A). The overpotential (η) reflects the response of electrocatalysts to alkaline HER at a given current density (j) (Fig. 4 B). For NiMoN/NC(500) NAs, η 10 , η 500 , η 1000 , and η 1500 at 10, 500, 1000, and 1500 mA cm − 2 respectively are 10.0, 159.7, 271.6, and 352.2mV, much lower than the benchmark Pt/C catalyst. The hydroxylation promotes the catalytic activity, and decreases η 10 , η 500 , η 1000 , and η 1500 to 5.8, 117.0, 200.6, and 260.6mV, respectively. Furthermore, Δη/Δlog|j| ratios well address the response of j to η for catalytic efficiencies over the wide range of current density (Fig. 4 C and Figure S19). 37 , 49 Δη/Δlog|j| of commercial Pt/C represents the sharp increase with current density. Besides the ultra-low η, Δη/Δlog|j| in NiMoN/NC(500) is as low as 12.9, 113.0, and 201.0mV⋅dec − 1 , and is further lowered by hydroxylation to 7.0, 99.0, and 153.1mV⋅dec − 1 in NiMoN/NC(500-R) over 4 ~ 10, 250 ~ 500, and 500 ~ 1000 mA⋅cm − 2 , respectively. In contrast, Ni 3 Mo 3 N/NC(600) and Mo 2 C/NC(700) give the larger η and Δη/Δlog|j| than NiMoN/NC(500), showing that the crystallization of catalysts is unfavorable to the catalytic activities. η and Δη/Δlog|j|, instead of the decrease in NiMoN/NC(500), are increased by ESRC in Mo 2 C/NC(700-R) but are hardly altered in Ni 3 Mo 3 N/NC(600-R). Evidently, the decomposition of Ni 3 Mo 3 N in Mo 2 C/NC(700-R) results in the absence of coupled dual-centers and conducts the most sluggish catalysis, which becomes more pronounced at enlarging current densities. It is the highly amorphized NiMoN/NC(500-R) NAs that has the richest coupled dual-centers to catalyze HER, responds sensitively to tiny current densities, and works ideally at industrial current densities. Kinetically, Tafel slope is an direct parameter to reflect HER mechanism. 50 NiMoN/NC(500) and NiMoN/NC(500-R) presents the Tafel slopes of 34.52 and 26.63mV dec − 1 , close to 39.4 and 29.6mV dec − 1 in Heyrovsky and Tafel reactions, respectively (Figure S20 and Scheme S1). Apparently, RDS is Tafel and Heyrovsky reactions on NiMoN/NC(500), and is Tafel reaction on NiMoN/NC(500-R) that is generally identified as RDS from the noble metal-based electrocatalysts in acidic HER. 51 In the absence of Ni-Mo species, by contrast, Mo 2 C/NC(700-R) give the Tafel slopes of 65.40mV dec − 1 , and Volmer reaction comes into play as RDS. Intrinsically, Tafel reaction as RDS in alkaline HER implies that HER rate depends mainly on H*- and H 2 -involved elementary steps, and NiMoN/NC(500-R) with the abundant coupled dual-centers works in water dissociation more efficient than NiMoN/NC(500) and much more than Mo 2 C/NC(700-R). Compared with the state-of-the-art catalytic activity in alkaline HER, therefore, NiMoN/NC(500-R) is superior not only to the transition metal-based electrocatalysts (Fig. 4 D and Table S2), but also to the noble metal-based electrocatalysts (Fig. 4 E and Table S3). The stability is a critical metric for commercial feasibility of NiMoN/NC(500-R), particularly, at large current densities. 52 After the CV was continuously run for 10,000 cycles, the negligible change from LSVs suggests the high cyclability of NiMoN/NC (500-R) (Fig. 4 F). As subjected to the chronoamperometry for examining long-term stability, NiMoN/NC(500-R) is run at 500 mA cm − 2 for 1,200h, and the LSVs show an overpotential increase by only 76.4 mV (Fig. 4 G). Quantitatively, C sta is introduced to evaluate catalyst stability following the equation: 53 C sta = jtΔE − 1 Where t is whole working time, and ΔE is overpotential difference after and before the test. NiMoN/NC(500-R) gives C sta of 2.76 × 10 7 C cm − 2 V − 1 , and surpasses the state-of-the-art HER catalysts (Fig. 4 H and Table S4). After the chronoamperometry, the unchanged array structure and phase composition show the strong mechanical and chemical stabilities of NiMoN/NC(500-R) NAs to tolerate the release of great amount of H 2 bubbles (Figure S21 and 22). It is the amorphization that imparts the robust flexibility to 3D NiMoN/NC(500-R) NAs, and underlies in the intrinsic stability to operate at high current densities. Moreover, the Faradaic efficiencies on NiMoN/NC(500-R) were respectively measured at 100 and 500 mA cm − 2 to be 99.93 and 98.47% (Figure S23), close to theoretical value, indicating the almost all charge utilization without parasitic-side reactions in H 2 production. 38 , 54 Bifunctional Mechanism To Circumvent Site-blocking Effect The hydroxylation significantly improve the catalysis of NiMoN/NC(500-R), but deactivate Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R) in HER. In this regard, the greatest ECSA lends the highly amorphized NiMoN/NC(500-R) with rooms large enough to conduct nonECS. As determined by double-layer capacitance (C dl ) (Figure S24-S25), 28 , 55 ECSA of NiMoN/NC(500) is 654.7 times larger than NF (Fig. 5 A), is extended by 42.0% in NiMoN/NC(500-R) owing to full hydroxylation as analyzed from OER and TGA (Fig. 2 C and S8). Because of crystallization phases, instead, ESRC respectively reduces ECSAs by 1.1 and 8.4% in Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R). Averagely, the coupled dual-centers in NiMoN/NC(500-R) are respectively separated by 4.0 and 9.5 folds more disperse than those in Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R) according to the roughly same metal loadings (Table S1). The better spaced active sites bring higher catalytic efficiencies as reflected by the exchange current density (j 0 ) and turnover frequency (TOF). 56 NiMoN/NC(500) gives j 0 of 7.56mA⋅cm − 2 , is comparable with Ni 3 Mo 3 N/NC(600) (6.31 mA⋅cm − 2 ), and prominent to Mo 2 C/NC(700) (1.01mA⋅cm − 2 ) (Figure S20 and S26). Correspondingly, ESRC increases j 0 with 34.8% in NiMoN/NC(500-R), but decreases j 0 with 4.5% and 41.6% respectively in Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R). At the overpotential of 100mV, TOF in NiMoN/NC(500-R) is 1.4, 1.8, 1.9, 11.1 and 14.1 times more than NiMoN/NC(500), Ni 3 Mo 3 N/NC(600), Ni 3 Mo 3 N/NC(600-R), Mo 2 C/NC(700) and Mo 2 C/NC(700-R) (Figure S27), respectively. Demonstrably, the coupled dual-centers of Ni-Mo species have lowest steric hindrances and best accessibility in NiMoN/NC(500-R), and become more activated by the inducement of surface hydroxylation. The designated electronic structures are necessary for coupled dual-centers to perform respective role in HER. Compared with Ni foil, X-ray absorption near-edge spectroscopy (XANES) of Ni K-edge in NiMoN/NC(500-R) shifts to higher energy, and increases in white-line intensity (Fig. 5 B), indicating the unoccupied states in Ni species that can support well to spilled H*. The projected density of states (PDOS) verify that the hydroxylation leads to electron redistribution through interactions of Ni with O (Figure S28). Below Fermi level (E f ), the denser PDOS of Ni atoms in HONiMoN suggest more electron delocalization than in NiMoN (Fig. 5 C), and favor H* adsorption and H 2 desorption. The Mo K-edge XANES in NiMoN/NC(500-R) moves to low energy close to adsorption edge of Mo foil (Fig. 5 D), and gives a valence state of 0.79 to accelerate water adsorption but not to weaken OH − 1 desorption (Figure S29). The hydroxylation removes the electrons from E f of Mo atoms in NiMoN, but their PDOS below E f remains roughly unchanged in HONiMoN, implying the suitable oxidation state to prefer water adsorption and OH − 1 desorption (Fig. 5 C). The coupled dual-centers bring about the concerted adsorptions in pre-reaction, and devote themselves to high charge accumulation and pseudocapacitance (C pseudo ) on NiMoN/NC(500-R). 57,58 Although no redox peak is detected from the CV curves (Figure S30), the current responses in the pulse voltammetry protocols at different applied potentials (E) behave as a capacitor owing to the accumulated charge (Q) (Figure S31). To avert bond rupture and formation, the linear fitting of Q against E is implemented in the potential region of 60 ~ 10mV without HER current (Figure S32), and the capacitance is obtained from the slope to be 8288.7mF cm − 2 for NiMoN/NC(500) and 9741.0mF cm − 2 for NiMoN/NC(500-R). C pseudo is calculated by subtracting C dl from the capacitance, and is 7443.7 mF cm − 2 for NiMoN/NC(500) and 8541.5 mF cm − 2 for NiMoN/NC(500-R) (Fig. 5 E, Figure S25). Evidently, the amorphization imparts catalysts with the superior stored-charge capacity. After ESRC, the hydroxylation further enhances C pseudo with ΔC pseudo (1097.8mF cm − 2 ) that is 3 times larger than ΔC dl (355.0mF cm − 2 ). The great C pseudo suggests the significant contribution of coupled dual-centers to pre-deprotonation, coincident with DFT-calculated strong adsorption of water. Moreover, the reaction order (α) for NiMoN/NC(500-R) (5.10) is more than that for NiMoN/NC(500) (4.21) from the slope of logj versus logQ (Fig. 5 E, Figure S33), indicating the hydroxylation to promote reaction rate through charge accumulation. Hence, we conclude that the coupled dual-centers give the heavy charge accumulation to initiate HER current, and the high catalytic activity of NiMoN/NC(500-R). The whole HER kinetics is expedited by the coupled bifunctional centers for different nonECS in NiMoN/NC(500-R), and unveiled by Operando electrochemical impedance spectroscopy (EIS) (Figure S34). There are two semicircles in a Nyquist plot that is fitted by Armstrong equivalent electric circuit (Figure S35). The semicircle in high frequency (R ct1 ) is associated with the mass transfer in nonECS, and the semicircle in low frequency (R ct2 ) is related to the electron transfer in electrochemical steps. 59 Commonly, R ct2 depends on intrinsic activity, drops monotonically with overpotential (Figure S36), and cannot clarify very different activities of catalysts, particularly at large current densities. Observably, R ct1 gives the second smallest value to NiMoN/NC(500), further is reduced by hydroxylation to the smallest one in NiMoN/NC(500-R), almost independent on the overpotentials (Fig. 5 F). Therefore, the circumvention of SBE gives the most efficient mass transfer through the coupled bifunctional centers to separate H*- and H 2 -involved elementary steps from H 2 O- and OH*-involved nonECS, and still hold the robust capability at ≥ 500mA cm − 2 in NiMoN/NC(500-R). Contrarily, Ni 3 Mo 3 N/NC(600) with crystallization gives larger R ct1 , and Mo 2 C/NC(700) without the coupled Ni-Mo centers has the largest R ct1 . After ESRC, R ct1 increases in Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R), and becomes far more detrimental to HER kinetics at high overpotentials. The evolutions of R ct1 with overpotentials are roughly similar to the dependences of η and Δη/Δlog|j| on current density, clearly, the construction of coupled dual-centers is critical to suppress recombination of H* with OH − and achieve the desired HER kinetics. Overall Water-splitting Performances For water electrolysis, the anode of NiFe-LDH/NiMoN/NC(500) NAs were prepared by electrodeposition of NiFe-layered double hydroxide (NiFe-LDH), using NiMoN/NC(500) as array template. The SEM images demonstrate that the array architecture is still held, and NiFe-LDH nanosheets grow epitaxially along NiMoN/NC nanorods to present the petal-like arrangements (Fig. 6 A and Figure S37). The XRD pattern verifies the deposition of NiFe-LDH on NiMoN/NC500 during electrochemical-treatment (Figure S38). The electrocatalysis of NiFe-LDH/NiMoN/NC(500) in alkaline OER is evaluated by LSVs in O 2 -saturated 1 M KOH, and the overpotentials of 228 and 300mV respectively deliver current densities of 100 and 500mA cm − 2 , better than NF-supported NiFe-LDH (306 and 392mV), much superior to the benchmark of NF-supported RuO 2 (Fig. 6 B). The great catalytic activity in OER profit from the array template of NiMoN/NC(500) to direct NiFe-LDH growth. Inspired by the excellent HER and OER performances, the water–alkali electrolyzers were assembled using NiFe-LDH/NiMoN/NC(500) or NiMoN/NC(500-R) as anode, NiMoN/NC(500-R), NiMoN/NC(500) or NiFe-LDH/NiMoN/NC(500) as cathode, and 1M KOH solution as electrolyte to estimate the practical overall water splitting. The polarization curves of overall water-splitting show that the NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) electrolyzer respectively exhibits an ultralow cell voltage of 1.530 and 1.607V at 100 and 500mA cm − 2 , lower than NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500) (1.577 and 1.648V), NiMoN/NC(500-R)ǁNiMoN/NC(500-R) (1.624 and 1.835 V) and NiFe-LDH/NiMoN/NC(500)ǁNiFe-LDH/NiMoN/NC (500) (1.781 and 1.975V) (Fig. 6 C). These results indicate that the asymmetric electrolyzer of NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) engenders ideal overall-water-splitting efficiency through the combination of catalysts with high HER and OER activities. Moreover, the operational stability of NiFe-LDH-NiMoN/NC(500)ǁNiMoN/NC(500-R) electrolyzer was tested by chronoamperometry at 500mA cm − 2 and cell voltages of 1.607V (Fig. 6 D). After the operation for 200h, this electrolyzer retain outstanding overall water splitting performance with a voltage drop of 15mV. The catalytic activity and stability are superior to most of the ever-reported water electrolyzers in alkaline media (Table S5). Discussion The almost amorphous Ni 0.76 Mo 1.24 and Mo 2 N are chemically embedded into the nitrogen-rich IL-derived carbons and set up the highly amorphized NiMoN/NC(500-R) NAs, and expand ECSA up to 929.8 times more than that of NF. Compared with Ni 3 Mo 3 N/NC(600-R) and Mo 2 C/NC(700-R), we reveal the coupled dual-centers of Ni-Mo species are induced by the amorphization and surface hydroxylation from ESRC, and the SBE of nonECS is circumvented by the bifunctional mechanism: one is H 2 O adsorption and OH − 1 desorption on the partially oxidized Mo species, the other is the H* spillover and H 2 desorption but undesirable for H 2 O adsorption on the fully hydroxylated Ni species. Thereby, the separation of H*- and H 2 -involved elementary steps from H 2 O- and OH*-involved nonECS impart NiMoN/NC (500-R) with the rapid mass transfer and heavy charge accumulation, and inhibit the recombination of H* with OH* to deliver superior catalytic efficiency in whole HER. Consequently, the ultra-low overpotentials of 5.8, 117.0 and 200.6mV, as well as Δη/Δlog|j| of 7.0, 99.0 and 153.1mV⋅dec − 1 , are respectively fulfilled by NiMoN/NC(500-R) at 10, 500 and 1000 mA cm − 2 , outperforming to Pt-based electrocatalysts. Although the crystallinity in the NAs is as low as 13.3%, attractively, NiMoN/NC(500-R) with the flexible nitrogen-rich skeleton can endure the harsh operation conditions of HER, and only gives an overpotential increment of 76.4 mV after lastingly run for 50 days at 500 mA cm − 2 . The work presents the generalizable paradigms to circumvent the SBE of nonECS through amorphization and surface reconstitution, and to design the highly amorphized NAs using various ionic liquids, meeting the commercialization requirements on electrocatalysts with high activity and durability beyond HER. Declarations Acknowledgements This work is supported by the National Natural Science Foundation of China (21573059 and 22208088). Author Contributions Hucheng Zhang and Huanli Jia conceived the project and designed experiments. Huanli Jia carried out the synthesis and performed materials characterization and electrochemical measurements. Hucheng Zhang, Haiyan Wang, Jianji Wang and Huanli Jia discussed the working mechanism. Huanli Jia, Ze Li. and Fangfang Yan analyzed the data. Xiaofang Su performed the DFT calculations. Huanli Jia, Hucheng Zhang, Haiyan Wang and Fangfang Yan wrote and revised the manuscript. All authors discussed the results and contributed to the final version of the manuscript. Competing interests There are no conflicts to declare. References Chu, S. et al. Opportunities and challenges for a sustainable energy future. Nature 488 , 294–303 (2012). Phil, De Luna. et al. What would it take for renewably powered electrosynthesis to displace petrochemical processes? Science 364 , 350 (2019) Seh, Z. W. et al . Combining theory and experiment in electrocatalysis: Insights into materials design. Science 355 , eaad4998 (2017). Yu, Z. Y. et al. Clean and affordable hydrogen fuel from alkaline water splitting: past, recent progress, and future prospects. Adv. Mater. 33 , 2007100 (2021). Sun, H. et al. Self-supported transition-metal-based electrocatalysts for hydrogen and oxygen evolution. Adv. Mater. 32 , 1806326 (2020). Zhu, Y. et al. Metal oxide-based materials as an emerging family of hydrogen evolution electrocatalysts. Energy Environ. Sci. 13 , 3361–3392 (2020). Zhuang, Y. et al. Three-dimensional open nano-netcage electrocatalysts for efficient pH-universal overall water splitting. Nat. Commun. 10, 4875 (2019). Wang, J. et al . Non-precious-metal catalysts for alkaline water electrolysis: operando characterizations, theoretical calculations, and recent advances. Chem. Soc. Rev. 49 , 9154–9196 (2020). Kim, J. et al. Theoretical and experimental understanding of hydrogen evolution reaction kinetics in alkaline electrolytes with Pt-based core−shell nanocrystals. J. Am. Chem. Soc . 141 , 18256−18263 (2019). Zheng, Y. et al. The hydrogen evolution reaction in alkaline solution: from theory, single crystal models, to practical electrocatalysts. Angew. Chem. Int. Ed. 57 , 7568 –7579 (2018). Song, D . et al. Highly porous Ni–P electrode synthesized by an ultrafast electrodeposition process for efficient overall water electrolysis. J. Mater. Chem. A 8 , 12069–12079 (2020). Yin, J. et al. Optimized metal chalcogenides for boosting water splitting. Adv. Sci. 7 , 1903070 (2020). Lu, J. et al. Carbon-encapsulated electrocatalysts for the hydrogen evolution reaction. Electrochem. Energy Rev. 2 , 105–127 (2019). Liu, Y. et al. A modulated electronic state strategy designed to integrate active HER and OER components as hybrid heterostructures for efficient overall water splitting. Appl Catal. B. 260 , 118197 (2020). Wang, J. et al . Single atom Ru doping 2H-MoS 2 as highly efficient hydrogen evolution reaction electrocatalyst in a wide pH range. Appl Catal. B. 298 , 120490 (2021). Wang, J .et al. Crystalline-amorphous Ni 2 P 4 O 12 /NiMoO x nanoarrays for alkaline water electrolysis: enhanced catalytic activity via in situ surface reconstruction. Small 18 , 2105972 (2022). Zhang, S. L . et al. Engineering platinum–cobalt nano-alloys in porous nitrogen-doped carbon nanotubes for highly efficient electrocatalytic hydrogen evolution. Ang ew. Chem. Int. Ed. 60 , 19068–19073 (2021). Sabhapathy, P . et al. Electronic structure modulation of isolated Co-N4 electrocatalyst by sulfur for improved pH-universal hydrogen evolution reaction. Nano Energy. 80 , 105544 (2021). Mahmood, N. et al . Electrocatalysts for hydrogen evolution in alkaline electrolytes: mechanisms, challenges, and prospective solutions. Adv. Sci. 5 , 1700464 (2018). Pradnya, M. et al . Nanostructured metal phosphide based catalysts for electrochemical water splitting: a review. Small 18 , 2107572 (2022). Zhang, J. et al. Modulation of inverse spinel Fe 3 O 4 by phosphorus doping as an industrially promising electrocatalyst for hydrogen evolution. Adv. Mater. 31 , 1905107 (2019). Zhang, B. et al. Simultaneous interfacial chemistry and inner Helmholtz plane regulating for superior alkaline hydrogen evolution. Energy Environ. Sci. 13 , 3007-3013 (2020). Liu, J. L. et al. Metal-organic framework-derived hierarchical ultrathin CoP nanosheets for overall water splitting. J. Mater. Chem. A. 8 , 19254−19261 (2020). Geng, B. et al. Conductive CuCo-based bimetal organic framework for efficient hydrogen evolution. Adv. Mater. 33 , 2106781 (2021). Li, Q. R. et al. Hierarchical Ni 3 N/Ni 0.2 Mo 0.8 N heterostructure nanorods arrays as efficient electrocatalysts for overall water and urea electrolysis. Chem. Eng. J. 409 , 128240 (2021). Ma, H. B . et al . Interface engineering of Co/CoMoN/NF heterostructures for high-performance electrochemical overall water splitting. Adv. Sci. 9 , 2105313 (2022). Deng, L. et al. Electronic modulation caused by interfacial Ni-O-M (M = Ru, Ir, Pd) bonding for accelerating hydrogen evolution kinetics. Angew. Chem. Int. Ed . 60 , 22276−22282 (2021). Zhang, X. et al. Lithiation-induced amorphization of Pd 3 P 2 S 8 for highly efficient hydrogen evolution. Nat. Catal. 1 , 460–468 (2018). Yang, H. et al. B-doping-induced amorphization of LDH for large-current-density hydrogen evolution reaction. Appl Catal. B. 261 , 118240 (2020). Anantharaj, S. et al . Surface amorphized nickel hydroxy sulphide for efficient hydrogen evolution reaction in alkaline medium. Chem. Eng. J. 408 , 127275 (2021). Niu, C. X. et al. Amorphous MoSx electro-synthesized in alkaline electrolyte for superior hydrogen evolution. J. Alloys Compd. 900 , 163509 (2022). Zhou, Y. et al. Electronegativity-Induced charge balancing to boost stability and activity of amorphous electrocatalyst. Adv. Mater. 34 , 2100537 (2022). Tian, J. K. et al. Recent advances of amorphous-phase-engineered metal-based catalysts for boosted electrocatalysis. J. Mater. Sci. Technol. 127 , 1–18 (2022). Luo, Y. T. et al. Recent advances in design of electrocatalysts for high-current-density water splitting. Adv. Mater. 34 , 2108133 (2022). Lao, M. M. et al . From fundamentals and theories to heterostructured electrocatalyst design: An in-depth understanding of alkaline hydrogen evolution reaction. Nano Energy. 98 , 107231 (2022). Liu, D. et al . Surface reconstruction and phase transition on vanadium–cobalt–iron trimetal nitrides to form active oxyhydroxide for enhanced electrocatalytic water oxidation. Adv. Energy Mater. 10 , 2002464 (2020). Luo, Y. T. et al. Stabilized hydroxide-mediated nickel-based electrocatalysts for high-current-density hydrogen evolution in alkaline media. Energy Environ. Sci. 14 , 4610-4619 (2021). Chen, Y. Y. et al . Self-templated fabrication of MoNi 4 /MoO 3-x nanoarrays with dual active components for highly efficent hydrogen evolution. Adv. Mater . 29 , 1703311 (2017). Xiao, M.J. et al . Carbon nano-onion encapsulated cobalt nanoparticles for oxygen reduction and lithium-ion batteries. J. Mater. Chem. A 9 , 7227 (2021). Louie, M. W. et al. An investigation of thin-film Ni−Fe oxide catalysts for the electrochemical evolution of oxygen. J. Am. Chem. Soc. 135 , 12329−12337 (2013). Wang, C. Z. et al. Redox bifunctional activities with optical gain of Ni 3 S 2 nanosheets edged with MoS 2 for overall water splitting. Appl Catal. B. 268 , 118435 (2020). Xu, Z. X. et al. Hierarchical Ni-Mo 2 C/N-doped carbon Mott-Schottky array for water electrolysis. Appl Catal. B. 292 , 120168 (2021). Yu, L. et al. Non-noble metal-nitride based electrocatalysts for high-performance alkaline seawater electrolysis. Nat. Commun. 10 , 5106 (2019). Yan, H. J. et al. Holey reduced graphene oxide coupled with an Mo 2 N–Mo 2 C heterojunction for efficient hydrogen evolution. Adv. Mater. 30 , 1704156 (2018). Jun, W. et al . Structure confined porous Mo 2 C for efficient hydrogen evolution. Adv. Funct. Mater. 27 , 1703933 (2017). Lyu, F. C. et al. Lamellarly stacking porous N, P co-doped Mo 2 C/C Nanosheets as high performance anode for lithium-ion batteries. Small 15 , 1805022 (2019). Dinh, C. T. et al. Multi-site electrocatalysts for hydrogen evolution in neutral media by destabilization of water molecules. Nat. Energy 4 , 107–114 (2019). Zhou, Z. et al. Big to Small: Ultrafine Mo 2 C particles derived from giant polyoxomolybdate clusters for hydrogen evolution reaction. Small 15 , 1900358 (2019). Luo, Y. et al. Morphology and surface chemistry engineering toward pH-universal catalysts for hydrogen evolution at high current density. Nat. Commun. 10 , 269 (2019). Liu, D. et al . Atomically dispersed platinum supported on curved carbon supports for efficient electrocatalytic hydrogen evolution. Nat. Energy 4 , 512–518 (2019). Fang, S. et al . Uncovering near-free platinum single-atom dynamics during electrochemical hydrogen evolution reaction. Nat. Commun . 11 , 1029 (2020). Zhang, J. et al . Single platinum atoms immobilized on an MXene as an efficient catalyst for the hydrogen evolution reaction. Nat. Catal. 1 , 985–992 (2018). Chen, Y. L. et al . Ultrafast self-heating synthesis of robust heterogeneous nanocarbides for high current density hydrogen evolution reaction. Nat. Commun. 13 , 3338 (2022). Wang, Z. Y. et al . Manipulation on active electronic states of metastable phase β-NiMoO 4 for large current density hydrogen evolution. Nat. Commun. 12 , 5960 (2021). Gao, S. et al. Partially oxidized atomic cobalt layers for carbon dioxide electroreduction to liquid fuel. Nature 529 , 68 (2016). Wang, D. et al . Atomic and electronic modulation of self-supported nickel-vanadium layered double hydroxide to accelerate water splitting kinetics. Nat. Commun. 10 , 3899 (2019). Nong, H. N. et al. Key role of chemistry versus bias in electrocatalytic oxygen evolution. Nature 587 , 408-413 (2020). Dai, Y. W. et al. Bridging the charge accumulation and high reaction order for high-rate oxygen evolution and long stable Zn-Air batteries. Adv. Funct. Mater. 32 , 2111989 (2022). Shen, L. F. et al. Interfacial structure of water as a new descriptor of the hydrogen evolution reaction. Angew. Chem. Int. Ed. 59 , 22397–22402 (2020). Zhang, J. et al . Efficient hydrogen production on MoNi 4 electrocatalysts with fast water dissociation kinetics. Nat. Commun. 8 , 15437 (2017). Zhang, H. C. et al. Electrochemical recognition of alkylimidazolium-mediated ultrafast charge transfer on graphene surfaces. Chem. Commun. 54 , 666 (2018). Additional Declarations There is NO Competing Interest. Supplementary Files EntryfortheTableofContents.docx SI.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2441531","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":168908636,"identity":"d8d60f94-aeda-438c-98d4-d696073b1f1c","order_by":0,"name":"Huanli Jia","email":"","orcid":"","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Huanli","middleName":"","lastName":"Jia","suffix":""},{"id":168908637,"identity":"3a17c2b7-377e-4746-ba22-1e08f11ef49d","order_by":1,"name":"Haiyan Wang","email":"","orcid":"","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Haiyan","middleName":"","lastName":"Wang","suffix":""},{"id":168908638,"identity":"482fe15a-e5e3-495b-94ab-a9b6677df6ef","order_by":2,"name":"Xiaofang Su","email":"","orcid":"https://orcid.org/0000-0003-1351-920X","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaofang","middleName":"","lastName":"Su","suffix":""},{"id":168908639,"identity":"650ad24a-911f-4a7b-a736-1076be10b9ca","order_by":3,"name":"Hucheng Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxElEQVRIiWNgGAWjYBACAwYeEGWTAObxkKAlLYGHVC2HSdBizn/24OeCX+fz7CUSGB+8bWOQNyekxbLhXLL0zL7bxTwSCcyGc9sYDHc2EHLYwR4Dad6e24k9Egls0rxtDAkGBwhpOcxj/Ju35xxIC/tv4rQc4zGT5vlxAGwLM3FazvCYWfM2JCf2nHnYLDnnnIThBoJazp8xvs3zxy6xvT354Ic3ZTbyBG0BA8Y2MNkAJCSIUQ8Cf4hVOApGwSgYBSMSAAAz5z4cK3zMjQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-4225-4319","institution":"Henan Normal University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Hucheng","middleName":"","lastName":"Zhang","suffix":""},{"id":168908640,"identity":"15e1fa87-dc16-4be4-b375-ef4450ec4b64","order_by":4,"name":"Fangfang Yan","email":"","orcid":"","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Fangfang","middleName":"","lastName":"Yan","suffix":""},{"id":168908641,"identity":"8f82e426-5a85-4d1c-a5e5-71062984a4b9","order_by":5,"name":"Ze Li","email":"","orcid":"","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Ze","middleName":"","lastName":"Li","suffix":""},{"id":168908642,"identity":"2f62fefc-9904-4e66-b794-748048627611","order_by":6,"name":"Jianji Wang","email":"","orcid":"","institution":"Henan Normal University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jianji","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2023-01-04 07:10:42","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2441531/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2441531/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":31828827,"identity":"c2d3fe47-5243-4536-b1d4-fc6d7542281b","added_by":"auto","created_at":"2023-01-19 21:40:28","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2125750,"visible":true,"origin":"","legend":"\u003cp\u003eMicroscopic structures of NiMoN/NC(500-R) NAs. (A) Schematic illustration of synthesis for 3D NiMoN/NC(500-R); SEM images of NiMoN/NC(500) NAs before (B) and after (C) ESRC; (D) STEM image of single nanorod; (E) high-resolution TEM image; (F) SAED patterns; (G) HAADF-STEM image; (H)~(L) EDS mapping images for elements of Mo, Ni, N, C, and O.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/5715e4866816c8efd4b27a74.jpeg"},{"id":31828826,"identity":"6f279cd7-6f2a-4e01-9c40-80a065a658a7","added_by":"auto","created_at":"2023-01-19 21:40:27","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":136225,"visible":true,"origin":"","legend":"\u003cp\u003eAnalyzing chemical components and hydroxylation in the electrocatalysts. (A) XRD patterns; (B) Raman spectra, (C) OER polarization curves at a scan rate of 2 mV s\u003csup\u003e−1\u003c/sup\u003e in 1 M KOH; and high-resolution XPS profiles of Ni 2p (D) and Mo 3d (E). Samples: NiMoO\u003csub\u003e4\u003c/sub\u003e·xH\u003csub\u003e2\u003c/sub\u003eO (a), NiMoN/NC(500) (b), NiMoN/NC(500-R) (c), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) (d), and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) (e).\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/6817c6202fc8951a22a72cf5.jpg"},{"id":31828283,"identity":"0b3c6b0b-71d9-44dc-a3ce-ea8b0ae82609","added_by":"auto","created_at":"2023-01-19 21:32:27","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":121052,"visible":true,"origin":"","legend":"\u003cp\u003eHydroxylation-mediated adsorption/desorption on the coupled dual-centers in HER. (A) Typical adsorption/desorption configurations; (B) Gibbs free energies of adsorbed H\u003csub\u003e2\u003c/sub\u003eO and OH* on Mo site of catalysts; (C) Adsorption free energy of spilled H* on different sites of NiMoN and HONiMoN.\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/325ee8395f5acbcd8f79e9f7.jpg"},{"id":31828288,"identity":"8032894d-8686-4d7a-96e6-6f05fc5bb489","added_by":"auto","created_at":"2023-01-19 21:32:28","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":168062,"visible":true,"origin":"","legend":"\u003cp\u003eCatalytic HER performances of the NAs in aqueous solution of 1M KOH at room temperature. (A) 90% iR-compensation LSVs at a scan rate of 2 mV s\u003csup\u003e−1\u003c/sup\u003e; (B) Overpotentials at different current densities; (C) Δη/Δlog|j| in different current-density ranges; (D) and (E) Comparison of overpotential and Tafel slope of NiMoN/NC(500-R) with transition metal-based (D) and noble metal-based (E) electrocatalysts in alkaline HER; (F) Cyclability of NiMoN/NC(500-R) through CV over the potential region between 0∼-0.3 V vs. RHE at a scan rate of 50 mV s\u003csup\u003e-1\u003c/sup\u003e; (G) Long-term stability of NiMoN/NC(500-R) at 500 mA cm\u003csup\u003e-2\u003c/sup\u003e, inset: LSV curves before and after stability test. (H) Comparison of long-term stability of NiMoN/NC(500-R) with the reported HER electrocatalysts. Electrocatalysts: NiMoN/NC(500) (a), NiMoN/NC(500-R) (b), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600) (c), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) (d), Mo\u003csub\u003e2\u003c/sub\u003eC/NC (700)(e), Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) (f), commercial Pt/C (g).\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/44d7c35f80b5e7d5bc1860e1.jpg"},{"id":31828286,"identity":"3a265a64-90a8-4b8e-97c2-80e754de5a13","added_by":"auto","created_at":"2023-01-19 21:32:27","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":163628,"visible":true,"origin":"","legend":"\u003cp\u003eInsight into catalytic mechanism of the coupled dual-centers in alkaline HER. (A) ECSAs relative to that of Ni foam, (B) and (D) the normalized Ni and Mo K-edge XANES profiles, the insets are the magnified K-edge XANES; (C) PDOS of Ni and Mo atoms in NiMoN and HONiMoN, the Fermi levels are set to zero; (G) Comparison of the stored-charge capacity and reaction order; (H) R\u003csub\u003eCT1\u003c/sub\u003e as the function of overpotential from the fitting results of operando EIS. Electrocatalysts: NiMoN/NC(500) (a), NiMoN/NC(500-R) (b), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600) (c), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) (d), Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) (e), Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) (f), commercial Ni foam (g).\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/e2444e688110cd281deb86aa.jpg"},{"id":31828289,"identity":"bd2f18c8-75f5-417a-a275-39e8141672f2","added_by":"auto","created_at":"2023-01-19 21:32:28","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":120347,"visible":true,"origin":"","legend":"\u003cp\u003eOverall water electrolysis. (A) SEM image of NiFe-LDH/NiMoN/NC(500); (B) Polarization curves of OER at a scan rate of 2 mV s\u003csup\u003e−1\u003c/sup\u003e in O\u003csub\u003e2\u003c/sub\u003e-saturated 1 M KOH aqueous solution; (C) Polarization curves of overall water-splitting at a scan rate of 2mV s\u003csup\u003e−1\u003c/sup\u003e in 1M KOH aqueous solution; Electrolyzers: NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) (a), NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500) (b), NiMoN/NC(500-R)ǁNiMoN/NC(500-R) (c), NiFe-LDH/NiMoN/NC(500)ǁNiFe-LDH/NiMoN/NC(500) (d). (D) Long-term durability of NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) in overall water-splitting, inset: the polarization curves before and after 200h test.\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/13e49a2c48bc64fcae23dae8.jpg"},{"id":33020939,"identity":"da755b4f-64fd-4556-9014-db1fdb38b807","added_by":"auto","created_at":"2023-02-16 09:21:13","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1196657,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/4c701fdc-5a36-477b-af71-ed5481bf2c07.pdf"},{"id":31828285,"identity":"711c92ee-25cf-4063-9597-9f7842a4fc8c","added_by":"auto","created_at":"2023-01-19 21:32:27","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":277795,"visible":true,"origin":"","legend":"","description":"","filename":"EntryfortheTableofContents.docx","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/d135d033d7d12608b7b17856.docx"},{"id":31828291,"identity":"c079b356-deba-4409-a0e1-8b5aa8da0dad","added_by":"auto","created_at":"2023-01-19 21:32:28","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":14649614,"visible":true,"origin":"","legend":"","description":"","filename":"SI.docx","url":"https://assets-eu.researchsquare.com/files/rs-2441531/v1/3604833917d085695de629ca.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"\u003cp\u003eHydroxylation-Inducing the Coupled Dual-Centers in Highly Amorphized Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e/Mo\u003csub\u003e2\u003c/sub\u003eN Nanoarrays with Superior Alkaline Hydrogen Evolution\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe increasing environmental concerns have motivated great interest in hydrogen energy that has high gravimetric energy density, earth abundance and wide applications without emitting pollutants.\u003csup\u003e\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e Currently, hydrogen evolution reaction (HER) from water has been recognized as the most promising technique of sustainable production as powered by clean electricity. However, the renewable grid supply-fluctuation of photovoltaics, wave and wind energies is imposed by spatial, temporal, climatic and seasonal factors. Therefore, the real-time conversion of these energies requires HER electrocatalysts that respond sensitively to the dynamical input power, and operate competently over a wide current-density range and long-term durability.\u003csup\u003e\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eAcidic HER usually is two to three orders of magnitude faster than alkaline HER,\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e,\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e but the vulnerable metal-based catalysts and proton exchange membrane in acidic solutions make large-scale hydrogen production to prefer in alkaline media.\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e,\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e Therefrom, the low-cost transition metal-based catalysts are intensively exploited to minimize HER barriers.\u003csup\u003e\u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16 CR17\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e Unfortunately, sluggish kinetics on the electrocatalysts incurs high overpotentials, and becomes particularly worse at industrial current densities (\u0026ge;\u0026thinsp;500 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e).\u003csup\u003e19,20\u003c/sup\u003e Currently, an effective strategy has been developed by vertically growing transition metal-based nanoarrays (NAs) on metal substrates, and the resultant monolithic catalysts are brought about smooth mass transfer and negligible interface electric-resistances, improving significantly in catalytic efficiency.\u003csup\u003e\u003cspan additionalcitationids=\"CR22 CR23 CR24 CR25 CR26\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e However, the NAs have high crystallinity with mechanical rigidity, industrially, are difficult to bear massive H\u003csub\u003e2\u003c/sub\u003e release. Although amorphization imparts catalysts with rich active sites, flexible architectures, desirable catalytic activity and durability,\u003csup\u003e\u003cb\u003e\u003cspan additionalcitationids=\"CR29 CR30 CR31 CR32\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/b\u003e\u003c/sup\u003e the amorphized NAs incline to geometrically collapse to increase charge and mass transfer barriers, and are not considered in previous literature.\u003c/p\u003e \u003cp\u003eAlkaline HER is launched from Volmer reaction, and followed by Heyrovsky or Tafel reaction (Scheme S1).\u003csup\u003e\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e,\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e The reaction rate is controlled by electrochemical steps and concomitant nonelectrochemical steps (nonECS). The electrochemical steps involve in electron transfer in H\u003csub\u003e2\u003c/sub\u003eO dissociation and concerted proton-electron transfer, and the nonECS embrace adsorption/diffusion of H\u003csub\u003e2\u003c/sub\u003eO, H*, H\u003csub\u003e2\u003c/sub\u003e and OH\u003csup\u003e\u0026minus;\u003c/sup\u003e. nonECS are directly related to site-blocking effect (SBE), and play the governed roles as the electron transfers are not rate-determining step (RDS). To circumvent SBE, ideally, we should decouple nonECS through integrating a site to catalyze Volmer reaction with another to catalyze Heyrovsky or Tafel reaction. Moreover, the separated elementary steps lower the whole reaction barrier more on the coupled dual-center electrocatalysts than on single active site, and give higher catalytic efficiencies. In fact, the electrocatalysis are designed rarely following the synergistic dual-center motivation to separately study multiple nonECS, and commonly is measured by HER activity with balancing H*, H\u003csub\u003e2\u003c/sub\u003eO and OH\u003csup\u003e\u0026minus;\u003c/sup\u003e interactions in single site. The key challenge lies in the coupled dual-center electrocatalysts requires enough partitioning spaces and favorable electronic structures to suppress SBE and recombination of H* with OH\u003csup\u003e\u0026minus;\u003c/sup\u003e in HER.\u003c/p\u003e \u003cp\u003eHere, we report the hydroxylation-conditioning nonECS to affect HER kinetics as revealed by density functional theory (DFT) calculations, pulse voltammetry, and \u003cem\u003eoperando\u003c/em\u003e electrochemical impedance spectroscopy (EIS). The crystalline NiMoO\u003csub\u003e4\u003c/sub\u003e arrays on nickel foam (NF) were nitrogenized by ionic liquid (IL) of 1-ethyl-3-methylimidazolium tetrazolate ([C\u003csub\u003e2\u003c/sub\u003emim][Tet], Scheme S2) at 500\u003csup\u003eo\u003c/sup\u003eC, and the resultant highly amorphized NAs are embedded with Mo\u003csub\u003e2\u003c/sub\u003eN and Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e in the skeleton of IL-derived nitrogen-rich carbons (NC). Subsequently, the Ni species are fully hydroxylated by the electrochemical surface reconstruction (ESRC) to harvest NiMoN/NC(500-R) NAs. It is demonstrated that the 3D self-supported architecture gives robust durability, efficient mass and charge transfer. Attractively, the amorphization and hydroxylation induce the super-large electrochemical surface area (ECSA), and create the active dual-centers to separate H*- and H\u003csub\u003e2\u003c/sub\u003e-involved elementary steps from H\u003csub\u003e2\u003c/sub\u003eO- and OH*-involved nonECS in NiMoN/NC(500-R) NAs. Thereby, the chemical coupling of Mo with Ni species provides the cooperative arenas for different nonECS, and significantly alleviate SBE to achieve the unexpected catalytic activity in alkaline HER.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eMicrostructural feature and surface hydroxylation.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe highly amorphized NiMoN/NC(500) NAs were synthesized by IL nitridation to split NiMoO\u003csub\u003e4\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO cuboid arrays (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA). NiMoO\u003csub\u003e4\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO nanorods with smooth surfaces have the average radial size of 0.54\u0026micro;m as shown in scanning electron microscopy (SEM) images (Figure S1). After the aqueous solution of IL was uniformly coated on the hydrophilic surfaces, the thermal nitridation at 500\u0026deg;C converts NiMoO\u003csub\u003e4\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO to NiMoN/NC(500) NAs. The chemical conversion doesn\u0026rsquo;t alter the array morphology, but split the nanorods to slenderer ones with an average radial size of 0.18\u0026micro;m (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eB). Subsequently, NiMoN/NC(500) was activated by ESRC with 100 circles of cyclic voltammetry (CV) between 1.4~-0.4V vs. RHE in 1M KOH, and the resultant NiMoN/NC(500-R) presents a little blurrier appearances owing to the surface hydroxylation (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eC).\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e As shown by scanning transmission electron microscopy (STEM) image, the nanorod from NiMoN/NC(500-R) NAs is built by the closely packed nanoparticles (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eD), and renders the electrocatalyst with the fully expanded ECSA. The phase interfaces are identified by the lattice spaces of 0.240 and 0.209 nm that are respectively indexed to (111) and (114) planes of Mo\u003csub\u003e2\u003c/sub\u003eN and Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e in high-resolution TEM (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eE). The paragenesis of Mo\u003csub\u003e2\u003c/sub\u003eN\u0026nbsp;\u003cspan style=\"text-align: inherit;\"\u003eand Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e0.76\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e1.24\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e is further evidenced by their spots/circles in selected electron area diffraction (SAED) patterns (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e1\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eF). Moreover, the angle annular dark field (HAADF)-STEM image and energy dispersive X-ray spectroscopy (EDS) mapping images verify the homogeneous element distributions over the nanorod, and imply that Mo and Ni species are embedded into NC (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e1\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eG\u0026thinsp;~\u0026thinsp;L). Instead of simple chemical digestion, interestingly, the thermal nitridation of IL split nanorods into slimmer ones, and simultaneously the arrays are well maintained in NiMoN/NC(500). The fact is clarified by the morphologic evolutions with IL loadings on NiMoO\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e4\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e\u0026middot;xH\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eO arrays (Figure S2). As calcined at 500\u0026deg;C, IL of 25mg chemically modifies NiMoO\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e4\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e nanorods to present rough surfaces. Increasing IL to 50mg, the most of nanorods are axially hollowed out, and some are split into finer ones. If introducing 200mg IL, the nanorods interconnect one another to give the 3D mesoporous network. It is the optimized IL loading of 100mg that renders NiMoN/NC(500) with the finest NAs and the fully exposed active sites.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003eThe crystalline-phases and crystallinity are analyzed by X-ray diffraction (XRD) patterns. Except the incomplete conversion of NiMoO\u003csub\u003e4\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO at 400\u0026deg;C (Figure S3), as comparison, we synthesized Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) NAs respectively at 600 and 700\u0026deg;C, following the similar procedures for NiMoN/NC(500). Combining the analyses on their powders without NF interferences (Figure S4), the crystalline phases are Mo\u003csub\u003e2\u003c/sub\u003eN and Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e in NiMoN/NC(500) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eA), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600), and Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN and \u0026beta;-Mo\u003csub\u003e2\u003c/sub\u003eC in Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) (Figure S5). As subjected to ESRC, the XRD patterns are not altered in NiMoN/NC(500-R) and Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R), whereas the Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN diffractions disappear in Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R). The disintegration of crystalline Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN is verified by the more amorphous appearances of Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) than the other samples (Figure S6). Noticeably, the most broadened diffraction profiles imply the highly dispersed crystalline-phases in NiMoN/NC(500-R). Reference to the (221) diffraction of Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600), quantitatively, the relative crystallinity of NiMoN/NC (500-R) is evaluated to be only 13.3% by the full width of half maximum of (111) diffraction of Mo\u003csub\u003e2\u003c/sub\u003eN (Figure S7). Despite of the very low \u0026chi;\u003csub\u003eC\u003c/sub\u003e, NiMoN/NC(500-R) is most antioxidative in air even under high temperature owing to the profound surface hydroxylation (Figure S8) as shown by linear sweep voltamogram (LSV) of oxygen evolution reaction (OER) and X-ray photoelectron spectroscopy (XPS) analysis later. In Raman spectra, moreover, the disappearances of bending (344.9 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and stretching (940.8 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) vibrations of Mo-O\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e give the additional proof of NiMoO\u003csub\u003e4\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO conversions (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eB, Figure S9), and the D and G bands indicate IL-derived carbons from the pyrolysis of IL.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e The metal element contents hold almost unchanged in these electrocatalysts from the analyses of inductively coupled plasma source mass spectrometer and survey scans of XPS (Figure S10, Table S1). Obviously, the self-supporting NiMoN/NC(500-R) NAs were mainly constructed by integrating NC with highly amorphized Mo\u003csub\u003e2\u003c/sub\u003eN and Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e together.\u003c/p\u003e\n\u003cp\u003eNi\u003csup\u003e2+\u003c/sup\u003e(Ni(OH)\u003csub\u003e2\u0026minus;\u0026delta;\u003c/sub\u003e)/Ni\u003csup\u003e3+\u003c/sup\u003e(NiOOH) oxidation peak indicates the electrooxidation in Ni-based catalysts in OER,\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e40\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e and is altered by surface hydroxylation. At 10mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e in LSV, the potential increases from 1.317V for NiMoN/NC(500) to 1.349V for NiMoN/NC(500-R) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eC). The increment of 32mV is ascribed to higher barrier of surface oxidation, and implies that the electrooxidation is deactivated by ESRC owing to deepening hydroxylation. Comparatively, the oxidation potential of Ni\u003csup\u003e2+\u003c/sup\u003e at 10mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) is 21mV more than in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600), and is almost same in Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) (Figure S11). Hence, the surfaces of NiMoN/NC(500-R) are profoundly hydroxylated by ESRC, Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) moderately, and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) weakly. The surface hydroxylation is further clarified by the dominant OH species from high-resolution XPS of O 1s in three post-electrcatalysts (Figure S12).\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e42\u003c/span\u003e\u003c/sup\u003e Except C-metal species, the binding energies of each species are same in the deconvoluted O1s, N1s, C1s spectra before and after ESRC (Figure S12-S14), \u003csup\u003e\u003cspan class=\"CitationRef\"\u003e43\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e46\u003c/span\u003e\u003c/sup\u003e implying that the nonmetal elements situate in similar chemical surroundings and are not the crucial factors to raise distinct catalytic activities.\u003c/p\u003e\n\u003cp\u003eAs active Ni-Mo species, their surface valence states depend heavily on annealing temperature, and evolve with ESRC to achieve favorable electronic structures for HER. As compared with three pre-catalysts (Figure S15), all post-catalysts indicate the enhanced signals of Ni-O species but the weakened ones of Ni-Mo and Ni\u003csup\u003e0 37,43,47\u003c/sup\u003eowing to ESRC hydroxylation (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eD). Distinctively, the disintegration of crystalline Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN in Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R), consistent with XRD\u0026nbsp;\u003cspan style=\"text-align: inherit;\"\u003eresult, is verified by the almost disappearing peak of Ni\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e0\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e/Ni-Mo, and suggests the hydroxylation largely destructs the chemical bonding and coupling of Ni with Mo atoms. Evidently, the three post-catalysts represent the same valence states of Ni\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e0\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e/Ni-Mo, but NiMoN/NC(500-R) has the binding energy of Ni-O that are 0.3eV lower than Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN/NC(600-R) and Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700-R), and are more nucleophilic to support the spilled H*. Furthermore, Mo-N and Mo-C species are derived from the chemical combination of Mo element with NC. Mo-C species is not detected in NiMoN/NC(500-R), but present in Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN/NC(600-R) and Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700-R) that respectively give the binding energies of 0.5 and 0.8 eV lower than Mo-N (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e2\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eE). As transferred to measuring system, the deconvoluted peaks of Mo\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e4+\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e and Mo\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e6+\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e indicate that Mo species in catalyst surfaces are readily oxidized by air,\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e\u003cspan class=\"CitationRef\"\u003e43\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e48\u003c/span\u003e\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e and the oxidized Mo sites are more electrophilic to adsorb water. Therefore, the catalytic dual-centers from Ni-Mo bonding are constructed by coupling of the partially oxidized Mo species with the fully hydroxylated Ni species. Considering the crystalline-phases, reasonably, the coupled dual-centers of Ni-Mo species are most abundant on the highly amorphized NiMoN/NC(500-R), moderate on the crystalline Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN/NC(600-R), and almost absent on Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700-R) without Ni-Mo bonding.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003eEvidently, the surface-hydroxylation is necessary to induce the coupled dual-centers to circumvent SBE of onoECS, and is analyzed by the adsorption thermodynamics from DFT-calculations with the structural models (Figure S16). The nonECS in HER involves mainly with the adsorption of H\u003csub\u003e2\u003c/sub\u003eO and H* along with desorption of OH* and H\u003csub\u003e2\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA). The Gibbs free energy (\u0026Delta;G\u003csub\u003eH2O\u003c/sub\u003e) indicates the Mo site presents the strongest adsorption (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB), whereas the adsorbed H\u003csub\u003e2\u003c/sub\u003eO on Ni site is undesirable on dual-center HONiMoN (Figure S17). Comparatively, a slightly exothermal process is implied\u0026nbsp;\u003cspan style=\"text-align: inherit;\"\u003eby the similar small \u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eH2O\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e on Mo and Ni sites of NiMoN. Once the adsorbed H\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eO is dissociated by the applied bias, OH* is left behind on Mo site, and the concomitant H* spills over the catalysts. Therein, OH* desorption from HONiMoN into bulk is thermodynamically most favorable as suggested by the positive \u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eOH*\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e of 0.17eV (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e3\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eB). Moreover, |\u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eH*\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e| of the spilled H* on Ni site of HONiMoN give the most reasonable value of 0.15 eV close to zero, and the optimal energy barrier for H* adsorption and H\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e desorption (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e3\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eC). By contrast, \u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eH2O\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e, \u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eOH*\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e and |\u0026Delta;G\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003eH*\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003e| in HOONiMoN respectively indicate the thermodynamically unfavourable adsorption/desorption in HER (Fig.\u0026nbsp;\u003c/span\u003e\u003cspan class=\"InternalRef\" style=\"text-align: inherit;\"\u003e3\u003c/span\u003e\u003cspan style=\"text-align: inherit;\"\u003eB and Figure S18), and clarify that the NiOOH with high valence state, instead of Ni-OH, impairs the catalytic activity. Consistent with XPS analyses, the nonmetallic O atoms are not dominant factors to affect the catalytic activities. Thereby, the coupled dual-centers are induced by hydroxylation, and each center performs its own functions to circumvent SBE and alleviate recombination of H* with OH\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e-\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e on HER catalysts.\u003c/span\u003e\u003c/p\u003e\n\u003ch3\u003eElectrocatalysis In Hydrogen Evolution\u003c/h3\u003e\n\u003cp\u003eThe electrocatalytic activities are evaluated by LSVs with 90% iR-compensation in 1M KOH, and the commercial Pt/C was employed for comparison (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eA). The overpotential (\u0026eta;) reflects the response of electrocatalysts to alkaline HER at a given current density (j) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eB). For NiMoN/NC(500) NAs, \u0026eta;\u003csub\u003e10\u003c/sub\u003e, \u0026eta;\u003csub\u003e500\u003c/sub\u003e, \u0026eta;\u003csub\u003e1000\u003c/sub\u003e, and \u0026eta;\u003csub\u003e1500\u003c/sub\u003e at 10, 500, 1000, and 1500 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e respectively are 10.0, 159.7, 271.6, and 352.2mV, much lower than the benchmark Pt/C catalyst. The hydroxylation promotes the catalytic activity, and decreases \u0026eta;\u003csub\u003e10\u003c/sub\u003e, \u0026eta;\u003csub\u003e500\u003c/sub\u003e, \u0026eta;\u003csub\u003e1000\u003c/sub\u003e, and \u0026eta;\u003csub\u003e1500\u003c/sub\u003e to 5.8, 117.0, 200.6, and 260.6mV, respectively. Furthermore, \u0026Delta;\u0026eta;/\u0026Delta;log|j| ratios well address the response of j to \u0026eta; for catalytic efficiencies over the wide range of current density (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eC and Figure S19).\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e \u0026Delta;\u0026eta;/\u0026Delta;log|j| of commercial Pt/C represents the sharp increase with current density. Besides the ultra-low \u0026eta;, \u0026Delta;\u0026eta;/\u0026Delta;log|j| in NiMoN/NC(500) is as low as 12.9, 113.0, and 201.0mV\u0026sdot;dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and is further lowered by hydroxylation to 7.0, 99.0, and 153.1mV\u0026sdot;dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e in NiMoN/NC(500-R) over 4\u0026thinsp;~\u0026thinsp;10, 250\u0026thinsp;~\u0026thinsp;500, and\u0026nbsp;\u003cspan style=\"text-align: inherit;\"\u003e500\u0026thinsp;~\u0026thinsp;1000 mA\u0026sdot;cm\u003c/span\u003e\u003csup style=\"text-align: inherit;\"\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003cspan style=\"text-align: inherit;\"\u003e, respectively. In contrast, Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN/NC(600) and Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700) give the larger \u0026eta; and \u0026Delta;\u0026eta;/\u0026Delta;log|j| than NiMoN/NC(500), showing that the crystallization of catalysts is unfavorable to the catalytic activities. \u0026eta; and \u0026Delta;\u0026eta;/\u0026Delta;log|j|, instead of the decrease in NiMoN/NC(500), are increased by ESRC in Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700-R) but are hardly altered in Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN/NC(600-R). Evidently, the decomposition of Ni\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eMo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e3\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eN in Mo\u003c/span\u003e\u003csub style=\"text-align: inherit;\"\u003e2\u003c/sub\u003e\u003cspan style=\"text-align: inherit;\"\u003eC/NC(700-R) results in the absence of coupled dual-centers and conducts the most sluggish catalysis, which becomes more pronounced at enlarging current densities. It is the highly amorphized NiMoN/NC(500-R) NAs that has the richest coupled dual-centers to catalyze HER, responds sensitively to tiny current densities, and works ideally at industrial current densities.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003eKinetically, Tafel slope is an direct parameter to reflect HER mechanism.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e50\u003c/span\u003e\u003c/sup\u003e NiMoN/NC(500) and NiMoN/NC(500-R) presents the Tafel slopes of 34.52 and 26.63mV dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, close to 39.4 and 29.6mV dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e in Heyrovsky and Tafel reactions, respectively (Figure S20 and Scheme S1). Apparently, RDS is Tafel and Heyrovsky reactions on NiMoN/NC(500), and is Tafel reaction on NiMoN/NC(500-R) that is generally identified as RDS from the noble metal-based electrocatalysts in acidic HER.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e In the absence of Ni-Mo species, by contrast, Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) give the Tafel slopes of 65.40mV dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and Volmer reaction comes into play as RDS. Intrinsically, Tafel reaction as RDS in alkaline HER implies that HER rate depends mainly on H*- and H\u003csub\u003e2\u003c/sub\u003e-involved elementary steps, and NiMoN/NC(500-R) with the abundant coupled dual-centers works in water dissociation more efficient than NiMoN/NC(500) and much more than Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R). Compared with the state-of-the-art catalytic activity in alkaline HER, therefore, NiMoN/NC(500-R) is superior not only to the transition metal-based electrocatalysts (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eD and Table S2), but also to the noble metal-based electrocatalysts (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eE and Table S3).\u003c/p\u003e\n\u003cp\u003eThe stability is a critical metric for commercial feasibility of NiMoN/NC(500-R), particularly, at large current densities.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e52\u003c/span\u003e\u003c/sup\u003e After the CV was continuously run for 10,000 cycles, the negligible change from LSVs suggests the high cyclability of NiMoN/NC (500-R) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eF). As subjected to the chronoamperometry for examining long-term stability, NiMoN/NC(500-R) is run at 500 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e for 1,200h, and the LSVs show an overpotential increase by only 76.4 mV (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eG). Quantitatively, C\u003csub\u003esta\u003c/sub\u003e is introduced to evaluate catalyst stability following the equation:\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e53\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eC\u003csub\u003esta\u003c/sub\u003e = jt\u0026Delta;E\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eWhere t is whole working time, and \u0026Delta;E is overpotential difference after and before the test. NiMoN/NC(500-R) gives C\u003csub\u003esta\u003c/sub\u003e of 2.76 \u0026times; 10\u003csup\u003e7\u003c/sup\u003e C cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e V\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and surpasses the state-of-the-art HER catalysts (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003eH and Table S4). After the chronoamperometry, the unchanged array structure and phase composition show the strong mechanical and chemical stabilities of NiMoN/NC(500-R) NAs to tolerate the release of great amount of H\u003csub\u003e2\u003c/sub\u003e bubbles (Figure S21 and 22). It is the amorphization that imparts the robust flexibility to 3D NiMoN/NC(500-R) NAs, and underlies in the intrinsic stability to operate at high current densities. Moreover, the Faradaic efficiencies on NiMoN/NC(500-R) were respectively measured at 100 and 500 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e to be 99.93 and 98.47% (Figure S23), close to theoretical value, indicating the almost all charge utilization without parasitic-side reactions in H\u003csub\u003e2\u003c/sub\u003e production.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e38\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e54\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\n\u003ch3\u003eBifunctional Mechanism To Circumvent Site-blocking Effect\u003c/h3\u003e\n\u003cp\u003eThe hydroxylation significantly improve the catalysis of NiMoN/NC(500-R), but deactivate Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) in HER. In this regard, the greatest ECSA lends the highly amorphized NiMoN/NC(500-R) with rooms large enough to conduct nonECS. As determined by double-layer capacitance (C\u003csub\u003edl\u003c/sub\u003e) (Figure S24-S25),\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e,\u003cspan class=\"CitationRef\"\u003e55\u003c/span\u003e\u003c/sup\u003e ECSA of NiMoN/NC(500) is 654.7 times larger than NF (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eA), is extended by 42.0% in NiMoN/NC(500-R) owing to full hydroxylation as analyzed from OER and TGA (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eC and S8). Because of crystallization phases, instead, ESRC respectively reduces ECSAs by 1.1 and 8.4% in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R). Averagely, the coupled dual-centers in NiMoN/NC(500-R) are respectively separated by 4.0 and 9.5 folds more disperse than those in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) according to the roughly same metal loadings (Table S1). The better spaced active sites bring higher catalytic efficiencies as reflected by the exchange current density (j\u003csub\u003e0\u003c/sub\u003e) and turnover frequency (TOF).\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e56\u003c/span\u003e\u003c/sup\u003e NiMoN/NC(500) gives j\u003csub\u003e0\u003c/sub\u003e of 7.56mA\u0026sdot;cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e, is comparable with Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600) (6.31 mA\u0026sdot;cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e), and prominent to Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) (1.01mA\u0026sdot;cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e) (Figure S20 and S26). Correspondingly, ESRC increases j\u003csub\u003e0\u003c/sub\u003e with 34.8% in NiMoN/NC(500-R), but decreases j\u003csub\u003e0\u003c/sub\u003e with 4.5% and 41.6% respectively in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R). At the overpotential of 100mV, TOF in NiMoN/NC(500-R) is 1.4, 1.8, 1.9, 11.1 and 14.1 times more than NiMoN/NC(500), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600), Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R), Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R) (Figure S27), respectively. Demonstrably, the coupled dual-centers of Ni-Mo species have lowest steric hindrances and best accessibility in NiMoN/NC(500-R), and become more activated by the inducement of surface hydroxylation.\u003c/p\u003e\n\u003cp\u003eThe designated electronic structures are necessary for coupled dual-centers to perform respective role in HER. Compared with Ni foil, X-ray absorption near-edge spectroscopy (XANES) of Ni K-edge in NiMoN/NC(500-R) shifts to higher energy, and increases in white-line intensity (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eB), indicating the unoccupied states in Ni species that can support well to spilled H*. The projected density of states (PDOS) verify that the hydroxylation leads to electron redistribution through interactions of Ni with O (Figure S28). Below Fermi level (E\u003csub\u003ef\u003c/sub\u003e), the denser PDOS of Ni atoms in HONiMoN suggest more electron delocalization than in NiMoN (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eC), and favor H* adsorption and H\u003csub\u003e2\u003c/sub\u003e desorption. The Mo K-edge XANES in NiMoN/NC(500-R) moves to low energy close to adsorption edge of Mo foil (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eD), and gives a valence state of 0.79 to accelerate water adsorption but not to weaken OH\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e desorption (Figure S29). The hydroxylation removes the electrons from E\u003csub\u003ef\u003c/sub\u003e of Mo atoms in NiMoN, but their PDOS below E\u003csub\u003ef\u003c/sub\u003e remains roughly unchanged in HONiMoN, implying the suitable oxidation state to prefer water adsorption and OH\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e desorption (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eC).\u003c/p\u003e\n\u003cp\u003eThe coupled dual-centers bring about the concerted adsorptions in pre-reaction, and devote themselves to high charge accumulation and pseudocapacitance (C\u003csub\u003epseudo\u003c/sub\u003e) on NiMoN/NC(500-R).\u003csup\u003e57,58\u003c/sup\u003e Although no redox peak is detected from the CV curves (Figure S30), the current responses in the pulse voltammetry protocols at different applied potentials (E) behave as a capacitor owing to the accumulated charge (Q) (Figure S31). To avert bond rupture and formation, the linear fitting of Q against E is implemented in the potential region of 60\u0026thinsp;~\u0026thinsp;10mV without HER current (Figure S32), and the capacitance is obtained from the slope to be 8288.7mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e for NiMoN/NC(500) and 9741.0mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e for NiMoN/NC(500-R). C\u003csub\u003epseudo\u003c/sub\u003e is calculated by subtracting C\u003csub\u003edl\u003c/sub\u003e from the capacitance, and is 7443.7 mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e for NiMoN/NC(500) and 8541.5 mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e for NiMoN/NC(500-R) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eE, Figure S25). Evidently, the amorphization imparts catalysts with the superior stored-charge capacity. After ESRC, the hydroxylation further enhances C\u003csub\u003epseudo\u003c/sub\u003e with \u0026Delta;C\u003csub\u003epseudo\u003c/sub\u003e (1097.8mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e) that is 3 times larger than \u0026Delta;C\u003csub\u003edl\u003c/sub\u003e (355.0mF cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e). The great C\u003csub\u003epseudo\u003c/sub\u003e suggests the significant contribution of coupled dual-centers to pre-deprotonation, coincident with DFT-calculated strong adsorption of water. Moreover, the reaction order (\u0026alpha;) for NiMoN/NC(500-R) (5.10) is more than that for NiMoN/NC(500) (4.21) from the slope of logj versus logQ (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eE, Figure S33), indicating the hydroxylation to promote reaction rate through charge accumulation. Hence, we conclude that the coupled dual-centers give the heavy charge accumulation to initiate HER current, and the high catalytic activity of NiMoN/NC(500-R).\u003c/p\u003e\n\u003cp\u003eThe whole HER kinetics is expedited by the coupled bifunctional centers for different nonECS in NiMoN/NC(500-R), and unveiled by Operando electrochemical impedance spectroscopy (EIS) (Figure S34). There are two semicircles in a Nyquist plot that is fitted by Armstrong equivalent electric circuit (Figure S35). The semicircle in high frequency (R\u003csub\u003ect1\u003c/sub\u003e) is associated with the mass transfer in nonECS, and the semicircle in low frequency (R\u003csub\u003ect2\u003c/sub\u003e) is related to the electron transfer in electrochemical steps.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e59\u003c/span\u003e\u003c/sup\u003e Commonly, R\u003csub\u003ect2\u003c/sub\u003e depends on intrinsic activity, drops monotonically with overpotential (Figure S36), and cannot clarify very different activities of catalysts, particularly at large current densities. Observably, R\u003csub\u003ect1\u003c/sub\u003e gives the second smallest value to NiMoN/NC(500), further is reduced by hydroxylation to the smallest one in NiMoN/NC(500-R), almost independent on the overpotentials (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eF). Therefore, the circumvention of SBE gives the most efficient mass transfer through the coupled bifunctional centers to separate H*- and H\u003csub\u003e2\u003c/sub\u003e-involved elementary steps from H\u003csub\u003e2\u003c/sub\u003eO- and OH*-involved nonECS, and still hold the robust capability at \u0026ge;\u0026thinsp;500mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e in NiMoN/NC(500-R). Contrarily, Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600) with crystallization gives larger R\u003csub\u003ect1\u003c/sub\u003e, and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700) without the coupled Ni-Mo centers has the largest R\u003csub\u003ect1\u003c/sub\u003e. After ESRC, R\u003csub\u003ect1\u003c/sub\u003e increases in Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R), and becomes far more detrimental to HER kinetics at high overpotentials. The evolutions of R\u003csub\u003ect1\u003c/sub\u003e with overpotentials are roughly similar to the dependences of \u0026eta; and \u0026Delta;\u0026eta;/\u0026Delta;log|j| on current density, clearly, the construction of coupled dual-centers is critical to suppress recombination of H* with OH\u003csup\u003e\u0026minus;\u003c/sup\u003e and achieve the desired HER kinetics.\u003c/p\u003e\n\u003ch3\u003eOverall Water-splitting Performances\u003c/h3\u003e\n\u003cp\u003eFor water electrolysis, the anode of NiFe-LDH/NiMoN/NC(500) NAs were prepared by electrodeposition of NiFe-layered double hydroxide (NiFe-LDH), using NiMoN/NC(500) as array template. The SEM images demonstrate that the array architecture is still held, and NiFe-LDH nanosheets grow epitaxially along NiMoN/NC nanorods to present the petal-like arrangements (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003eA and Figure S37). The XRD pattern verifies the deposition of NiFe-LDH on NiMoN/NC500 during electrochemical-treatment (Figure S38). The electrocatalysis of NiFe-LDH/NiMoN/NC(500) in alkaline OER is evaluated by LSVs in O\u003csub\u003e2\u003c/sub\u003e-saturated 1 M KOH, and the overpotentials of 228 and 300mV respectively deliver current densities of 100 and 500mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e, better than NF-supported NiFe-LDH (306 and 392mV), much superior to the benchmark of NF-supported RuO\u003csub\u003e2\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003eB). The great catalytic activity in OER profit from the array template of NiMoN/NC(500) to direct NiFe-LDH growth.\u003c/p\u003e\n\u003cp\u003eInspired by the excellent HER and OER performances, the water\u0026ndash;alkali electrolyzers were assembled using NiFe-LDH/NiMoN/NC(500) or NiMoN/NC(500-R) as anode, NiMoN/NC(500-R), NiMoN/NC(500) or NiFe-LDH/NiMoN/NC(500) as cathode, and 1M KOH solution as electrolyte to estimate the practical overall water splitting. The polarization curves of overall water-splitting show that the NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) electrolyzer respectively exhibits an ultralow cell voltage of 1.530 and 1.607V at 100 and 500mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e, lower than NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500) (1.577 and 1.648V), NiMoN/NC(500-R)ǁNiMoN/NC(500-R) (1.624 and 1.835 V) and NiFe-LDH/NiMoN/NC(500)ǁNiFe-LDH/NiMoN/NC (500) (1.781 and 1.975V) (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003eC). These results indicate that the asymmetric electrolyzer of NiFe-LDH/NiMoN/NC(500)ǁNiMoN/NC(500-R) engenders ideal overall-water-splitting efficiency through the combination of catalysts with high HER and OER activities. Moreover, the operational stability of NiFe-LDH-NiMoN/NC(500)ǁNiMoN/NC(500-R) electrolyzer was tested by chronoamperometry at 500mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e and cell voltages of 1.607V (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003eD). After the operation for 200h, this electrolyzer retain outstanding overall water splitting performance with a voltage drop of 15mV. The catalytic activity and stability are superior to most of the ever-reported water electrolyzers in alkaline media (Table S5).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe almost amorphous Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e and Mo\u003csub\u003e2\u003c/sub\u003eN are chemically embedded into the nitrogen-rich IL-derived carbons and set up the highly amorphized NiMoN/NC(500-R) NAs, and expand ECSA up to 929.8 times more than that of NF. Compared with Ni\u003csub\u003e3\u003c/sub\u003eMo\u003csub\u003e3\u003c/sub\u003eN/NC(600-R) and Mo\u003csub\u003e2\u003c/sub\u003eC/NC(700-R), we reveal the coupled dual-centers of Ni-Mo species are induced by the amorphization and surface hydroxylation from ESRC, and the SBE of nonECS is circumvented by the bifunctional mechanism: one is H\u003csub\u003e2\u003c/sub\u003eO adsorption and OH\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e desorption on the partially oxidized Mo species, the other is the H* spillover and H\u003csub\u003e2\u003c/sub\u003e desorption but undesirable for H\u003csub\u003e2\u003c/sub\u003eO adsorption on the fully hydroxylated Ni species. Thereby, the separation of H*- and H\u003csub\u003e2\u003c/sub\u003e-involved elementary steps from H\u003csub\u003e2\u003c/sub\u003eO- and OH*-involved nonECS impart NiMoN/NC (500-R) with the rapid mass transfer and heavy charge accumulation, and inhibit the recombination of H* with OH* to deliver superior catalytic efficiency in whole HER. Consequently, the ultra-low overpotentials of 5.8, 117.0 and 200.6mV, as well as Δη/Δlog|j| of 7.0, 99.0 and 153.1mV\u0026sdot;dec\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, are respectively fulfilled by NiMoN/NC(500-R) at 10, 500 and 1000 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e, outperforming to Pt-based electrocatalysts. Although the crystallinity in the NAs is as low as 13.3%, attractively, NiMoN/NC(500-R) with the flexible nitrogen-rich skeleton can endure the harsh operation conditions of HER, and only gives an overpotential increment of 76.4 mV after lastingly run for 50 days at 500 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e. The work presents the generalizable paradigms to circumvent the SBE of nonECS through amorphization and surface reconstitution, and to design the highly amorphized NAs using various ionic liquids, meeting the commercialization requirements on electrocatalysts with high activity and durability beyond HER.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgements\u003c/p\u003e\n\u003cp\u003eThis work is supported by the National Natural Science Foundation of China (21573059 and 22208088).\u003c/p\u003e\n\u003cp\u003eAuthor Contributions\u003c/p\u003e\n\u003cp\u003eHucheng Zhang and Huanli Jia conceived the project and designed experiments. Huanli Jia carried out the synthesis and performed materials characterization and electrochemical measurements. Hucheng Zhang, Haiyan Wang, Jianji Wang and Huanli Jia discussed the working mechanism. Huanli Jia, Ze Li. and Fangfang Yan analyzed the data. Xiaofang Su performed the DFT calculations. Huanli Jia, Hucheng Zhang, Haiyan Wang and Fangfang Yan wrote and revised the manuscript. All authors discussed the results and contributed to the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThere are no conflicts to declare.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eChu, S. \u003cem\u003eet al.\u003c/em\u003e Opportunities and challenges for a sustainable energy future. \u003cem\u003eNature\u003c/em\u003e \u003cstrong\u003e488\u003c/strong\u003e, 294\u0026ndash;303 (2012).\u003c/li\u003e\n\u003cli\u003ePhil, De Luna. \u003cem\u003eet al.\u003c/em\u003e What would it take for renewably powered electrosynthesis to displace petrochemical processes? \u003cem\u003eScience\u003c/em\u003e \u003cstrong\u003e364\u003c/strong\u003e, 350 (2019)\u003c/li\u003e\n\u003cli\u003eSeh, Z. W. \u003cem\u003eet al\u003c/em\u003e. Combining theory and experiment in electrocatalysis: Insights into materials design. \u003cem\u003eScience \u003c/em\u003e\u003cstrong\u003e355\u003c/strong\u003e, eaad4998 (2017). \u003c/li\u003e\n\u003cli\u003eYu, Z. Y. \u003cem\u003eet al.\u003c/em\u003e Clean and affordable hydrogen fuel from alkaline water splitting: past, recent progress, and future prospects. \u003cem\u003eAdv. Mater.\u003c/em\u003e\u003cstrong\u003e33\u003c/strong\u003e, 2007100 (2021).\u003c/li\u003e\n\u003cli\u003eSun, H.\u003cem\u003e et al.\u003c/em\u003e Self-supported transition-metal-based electrocatalysts for hydrogen and oxygen evolution. \u003cem\u003eAdv. Mater.\u003c/em\u003e \u003cstrong\u003e32\u003c/strong\u003e, 1806326 (2020).\u003c/li\u003e\n\u003cli\u003eZhu, Y. \u003cem\u003eet al.\u003c/em\u003e Metal oxide-based materials as an emerging family of hydrogen evolution electrocatalysts. \u003cem\u003eEnergy Environ. \u003c/em\u003e\u003cem style=\"text-align: inherit;\"\u003eSci.\u003c/em\u003e\u003cspan style=\"text-align: inherit;\"\u003e \u003c/span\u003e\u003cstrong style=\"text-align: inherit;\"\u003e13\u003c/strong\u003e\u003cspan style=\"text-align: inherit;\"\u003e, 3361\u0026ndash;3392 (2020).\u003c/span\u003e\u003c/li\u003e\n\u003cli\u003eZhuang, Y. \u003cem\u003eet al.\u003c/em\u003e Three-dimensional open nano-netcage electrocatalysts for efficient pH-universal overall water splitting. \u003cem\u003eNat. Commun.\u003c/em\u003e \u003cstrong\u003e10,\u003c/strong\u003e 4875 (2019).\u003c/li\u003e\n\u003cli\u003eWang, J. \u003cem\u003eet al\u003c/em\u003e. Non-precious-metal catalysts for alkaline water electrolysis: operando characterizations, theoretical calculations, and recent advances. \u003cem\u003eChem. Soc. Rev.\u003c/em\u003e \u003cstrong\u003e49\u003c/strong\u003e, 9154\u0026ndash;9196 (2020).\u003c/li\u003e\n\u003cli\u003eKim, J. \u003cem\u003eet al.\u003c/em\u003e Theoretical and experimental understanding of hydrogen evolution reaction kinetics in alkaline electrolytes with Pt-based core\u0026minus;shell nanocrystals. \u003cem\u003eJ. Am. Chem. Soc\u003c/em\u003e. \u003cstrong\u003e141\u003c/strong\u003e, 18256\u0026minus;18263 (2019).\u003c/li\u003e\n\u003cli\u003eZheng, Y. \u003cem\u003eet al.\u003c/em\u003e The hydrogen evolution reaction in alkaline solution: from theory, single crystal models, to practical electrocatalysts. \u003cem\u003eAngew. Chem. Int. Ed. \u003c/em\u003e\u003cstrong\u003e57\u003c/strong\u003e, 7568 \u0026ndash;7579 (2018).\u003c/li\u003e\n\u003cli\u003eSong, D\u003cem\u003e. \u003c/em\u003e\u003cem\u003eet al.\u003c/em\u003e Highly porous Ni\u0026ndash;P electrode synthesized by an ultrafast electrodeposition process for efficient overall water electrolysis.\u003cem\u003e J. Mater. Chem. A\u003c/em\u003e\u003cstrong\u003e 8\u003c/strong\u003e, 12069\u0026ndash;12079 (2020).\u003c/li\u003e\n\u003cli\u003eYin, J. \u003cem\u003eet al.\u003c/em\u003e Optimized metal chalcogenides for boosting water splitting. \u003cem\u003eAdv. Sci.\u003c/em\u003e \u003cstrong\u003e7\u003c/strong\u003e, 1903070 (2020).\u003c/li\u003e\n\u003cli\u003eLu, J. \u003cem\u003eet al. \u003c/em\u003eCarbon-encapsulated electrocatalysts for the hydrogen evolution reaction. \u003cem\u003eElectrochem. Energy Rev.\u003c/em\u003e \u003cstrong\u003e2\u003c/strong\u003e, 105\u0026ndash;127 (2019).\u003c/li\u003e\n\u003cli\u003eLiu, Y. \u003cem\u003eet al.\u003c/em\u003e A modulated electronic state strategy designed to integrate active HER and OER components as hybrid heterostructures for efficient overall water splitting. \u003cem\u003eAppl Catal. B. \u003c/em\u003e\u003cstrong\u003e260\u003c/strong\u003e, 118197 (2020).\u003c/li\u003e\n\u003cli\u003eWang, J. \u003cem\u003eet al\u003c/em\u003e. Single atom Ru doping 2H-MoS\u003csub\u003e2\u003c/sub\u003e as highly efficient hydrogen evolution reaction electrocatalyst in a wide pH range. \u003cem\u003eAppl Catal. B.\u003c/em\u003e \u003cstrong\u003e298\u003c/strong\u003e, 120490 (2021).\u003c/li\u003e\n\u003cli\u003eWang, J\u003cem\u003e.et al. \u003c/em\u003eCrystalline-amorphous Ni\u003csub\u003e2\u003c/sub\u003eP\u003csub\u003e4\u003c/sub\u003eO\u003csub\u003e12\u003c/sub\u003e/NiMoO\u003csub\u003ex\u003c/sub\u003e nanoarrays for alkaline water electrolysis: enhanced catalytic activity via in situ surface reconstruction.\u003cem\u003e Small \u003c/em\u003e\u003cstrong\u003e18\u003c/strong\u003e, 2105972 (2022). \u003c/li\u003e\n\u003cli\u003eZhang, S. L\u003cem\u003e. et al.\u003c/em\u003e Engineering platinum\u0026ndash;cobalt nano-alloys in porous nitrogen-doped carbon nanotubes for highly efficient electrocatalytic hydrogen evolution. Ang\u003cem\u003eew. Chem. Int. Ed.\u003c/em\u003e\u003cstrong\u003e 60\u003c/strong\u003e, 19068\u0026ndash;19073 (2021).\u003c/li\u003e\n\u003cli\u003eSabhapathy, P\u003cem\u003e. et al.\u003c/em\u003e Electronic structure modulation of isolated Co-N4 electrocatalyst by sulfur for improved pH-universal hydrogen evolution reaction. \u003cem\u003eNano Energy.\u003c/em\u003e\u003cstrong\u003e 80\u003c/strong\u003e, 105544 (2021).\u003c/li\u003e\n\u003cli\u003eMahmood, N. \u003cem\u003eet al\u003c/em\u003e. Electrocatalysts for hydrogen evolution in alkaline electrolytes: mechanisms, challenges, and prospective solutions. \u003cem\u003eAdv. Sci.\u003c/em\u003e \u003cstrong\u003e5\u003c/strong\u003e, 1700464 (2018).\u003c/li\u003e\n\u003cli\u003ePradnya, M. \u003cem\u003eet al\u003c/em\u003e. Nanostructured metal phosphide based catalysts for electrochemical water splitting: a review. \u003cem\u003eSmall \u003c/em\u003e\u003cstrong\u003e18\u003c/strong\u003e, 2107572 (2022).\u003c/li\u003e\n\u003cli\u003eZhang, J. \u003cem\u003eet al. \u003c/em\u003eModulation of inverse spinel Fe\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e by phosphorus doping as an industrially promising electrocatalyst for hydrogen evolution. \u003cem\u003eAdv. Mater.\u003c/em\u003e \u003cstrong\u003e31\u003c/strong\u003e, 1905107 (2019). \u003c/li\u003e\n\u003cli\u003eZhang, B. \u003cem\u003eet al.\u003c/em\u003e Simultaneous interfacial chemistry and inner Helmholtz plane regulating for superior alkaline hydrogen evolution. \u003cem\u003eEnergy Environ. Sci.\u003c/em\u003e \u003cstrong\u003e13\u003c/strong\u003e, 3007-3013 (2020).\u003c/li\u003e\n\u003cli\u003eLiu, J. L. \u003cem\u003eet al.\u003c/em\u003e\u003cem\u003e \u003c/em\u003eMetal-organic framework-derived hierarchical ultrathin CoP nanosheets for overall water splitting. \u003cem\u003eJ. Mater. Chem. A. \u003c/em\u003e\u003cstrong\u003e8\u003c/strong\u003e, 19254\u0026minus;19261 (2020).\u003c/li\u003e\n\u003cli\u003eGeng, B. \u003cem\u003eet al.\u003c/em\u003e Conductive CuCo-based bimetal organic framework for efficient hydrogen evolution. \u003cem\u003eAdv. Mater. \u003c/em\u003e\u003cstrong\u003e33\u003c/strong\u003e, 2106781 (2021).\u003c/li\u003e\n\u003cli\u003eLi, Q. R. \u003cem\u003eet al.\u003c/em\u003e Hierarchical Ni\u003csub\u003e3\u003c/sub\u003eN/Ni\u003csub\u003e0.2\u003c/sub\u003eMo\u003csub\u003e0.8\u003c/sub\u003eN heterostructure nanorods arrays as efficient electrocatalysts for overall water and urea electrolysis. \u003cem\u003eChem. Eng. J.\u003c/em\u003e\u003cem\u003e \u003c/em\u003e\u003cstrong\u003e409\u003c/strong\u003e, 128240 (2021).\u003c/li\u003e\n\u003cli\u003eMa, H. B\u003cem\u003e. et al\u003c/em\u003e. Interface engineering of Co/CoMoN/NF heterostructures for high-performance electrochemical overall water splitting. \u003cem\u003eAdv. Sci. \u003c/em\u003e\u003cstrong\u003e9\u003c/strong\u003e, 2105313 (2022).\u003c/li\u003e\n\u003cli\u003eDeng, L.\u003cem\u003e et al.\u003c/em\u003e Electronic modulation caused by interfacial Ni-O-M (M = Ru, Ir, Pd) bonding for accelerating hydrogen evolution kinetics. \u003cem\u003eAngew. Chem. Int. Ed\u003c/em\u003e. \u003cstrong\u003e60\u003c/strong\u003e, 22276\u0026minus;22282 (2021).\u003c/li\u003e\n\u003cli\u003eZhang, X. \u003cem\u003eet al.\u003c/em\u003e Lithiation-induced amorphization of Pd\u003csub\u003e3\u003c/sub\u003eP\u003csub\u003e2\u003c/sub\u003eS\u003csub\u003e8\u003c/sub\u003e for highly efficient hydrogen evolution. \u003cem\u003eNat. Catal.\u003c/em\u003e \u003cstrong\u003e1\u003c/strong\u003e, 460\u0026ndash;468 (2018).\u003c/li\u003e\n\u003cli\u003eYang, H. \u003cem\u003eet al.\u003c/em\u003e B-doping-induced amorphization of LDH for large-current-density hydrogen evolution reaction. \u003cem\u003eAppl Catal. B.\u003c/em\u003e\u003cem\u003e \u003c/em\u003e\u003cstrong\u003e261\u003c/strong\u003e, 118240 (2020).\u003c/li\u003e\n\u003cli\u003eAnantharaj, S. \u003cem\u003eet al\u003c/em\u003e. Surface amorphized nickel hydroxy sulphide for efficient hydrogen evolution reaction in alkaline medium. \u003cem\u003eChem. Eng. J. \u003c/em\u003e\u003cstrong\u003e408\u003c/strong\u003e, 127275 (2021).\u003c/li\u003e\n\u003cli\u003eNiu, C. X. \u003cem\u003eet al. \u003c/em\u003eAmorphous MoSx electro-synthesized in alkaline electrolyte for superior hydrogen evolution. \u003cem\u003eJ. Alloys Compd. \u003c/em\u003e\u003cstrong\u003e900\u003c/strong\u003e, 163509 (2022).\u003c/li\u003e\n\u003cli\u003eZhou, Y. \u003cem\u003eet al. \u003c/em\u003eElectronegativity-Induced charge balancing to boost stability and activity of amorphous electrocatalyst. \u003cem\u003eAdv. Mater.\u003c/em\u003e \u003cstrong\u003e34\u003c/strong\u003e, 2100537 (2022).\u003c/li\u003e\n\u003cli\u003eTian, J. K. \u003cem\u003eet al.\u003c/em\u003e Recent advances of amorphous-phase-engineered metal-based catalysts for boosted electrocatalysis. \u003cem\u003eJ. Mater. Sci. Technol. \u003c/em\u003e\u003cstrong\u003e127\u003c/strong\u003e, 1\u0026ndash;18 (2022).\u003c/li\u003e\n\u003cli\u003eLuo, Y. T. \u003cem\u003eet al.\u003c/em\u003e Recent advances in design of electrocatalysts for high-current-density water splitting. \u003cem\u003eAdv. Mater.\u003c/em\u003e \u003cstrong\u003e34\u003c/strong\u003e, 2108133 (2022).\u003c/li\u003e\n\u003cli\u003eLao, M. M. \u003cem\u003eet al\u003c/em\u003e. From fundamentals and theories to heterostructured electrocatalyst design: An in-depth understanding of alkaline hydrogen evolution reaction. \u003cem style=\"text-align: inherit;\"\u003eNano Energy.\u003c/em\u003e\u003cspan style=\"text-align: inherit;\"\u003e \u003c/span\u003e\u003cstrong style=\"text-align: inherit;\"\u003e98\u003c/strong\u003e\u003cspan style=\"text-align: inherit;\"\u003e, 107231 (2022).\u003c/span\u003e\u003c/li\u003e\n\u003cli\u003eLiu, D. \u003cem\u003eet al\u003c/em\u003e. Surface reconstruction and phase transition on vanadium\u0026ndash;cobalt\u0026ndash;iron trimetal nitrides to form active oxyhydroxide for enhanced electrocatalytic water oxidation. \u003cem\u003eAdv. Energy Mater.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 2002464 (2020).\u003c/li\u003e\n\u003cli\u003eLuo, Y. T. \u003cem\u003eet al.\u003c/em\u003e Stabilized hydroxide-mediated nickel-based electrocatalysts for high-current-density hydrogen evolution in alkaline media. \u003cem\u003eEnergy Environ. Sci. \u003c/em\u003e\u003cstrong\u003e14\u003c/strong\u003e, 4610-4619 (2021).\u003c/li\u003e\n\u003cli\u003eChen, Y. Y. \u003cem\u003eet al\u003c/em\u003e. Self-templated fabrication of MoNi\u003csub\u003e4\u003c/sub\u003e/MoO\u003csub\u003e3-x\u003c/sub\u003e nanoarrays with dual active components for highly efficent hydrogen evolution. \u003cem\u003eAdv. Mater\u003c/em\u003e. \u003cstrong\u003e29\u003c/strong\u003e, 1703311 (2017).\u003c/li\u003e\n\u003cli\u003eXiao, M.J. \u003cem\u003eet al\u003c/em\u003e. Carbon nano-onion encapsulated cobalt nanoparticles for oxygen reduction and lithium-ion batteries. \u003cem\u003eJ. Mater. Chem. A\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 7227 (2021).\u003c/li\u003e\n\u003cli\u003eLouie, M. W. \u003cem\u003eet al.\u003c/em\u003e An investigation of thin-film Ni\u0026minus;Fe oxide catalysts for the electrochemical evolution of oxygen.\u003cem\u003e J. Am. Chem. Soc. \u003c/em\u003e\u003cstrong\u003e135\u003c/strong\u003e, 12329\u0026minus;12337 (2013).\u003c/li\u003e\n\u003cli\u003eWang, C. Z. \u003cem\u003eet al.\u003c/em\u003e Redox bifunctional activities with optical gain of Ni\u003csub\u003e3\u003c/sub\u003eS\u003csub\u003e2\u003c/sub\u003e nanosheets edged with MoS\u003csub\u003e2\u003c/sub\u003e for overall water splitting. \u003cem\u003eAppl Catal. B.\u003c/em\u003e\u003cem\u003e \u003c/em\u003e\u003cstrong\u003e268\u003c/strong\u003e, 118435 (2020).\u003c/li\u003e\n\u003cli\u003eXu, Z. X. \u003cem\u003eet al.\u003c/em\u003e Hierarchical Ni-Mo\u003csub\u003e2\u003c/sub\u003eC/N-doped carbon Mott-Schottky array for water electrolysis. \u003cem\u003eAppl Catal. B.\u003c/em\u003e \u003cstrong\u003e292\u003c/strong\u003e, 120168 (2021).\u003c/li\u003e\n\u003cli\u003eYu, L. \u003cem\u003eet al.\u003c/em\u003e Non-noble metal-nitride based electrocatalysts for high-performance alkaline seawater electrolysis. \u003cem\u003eNat. Commun. \u003c/em\u003e\u003cstrong\u003e10\u003c/strong\u003e, 5106 (2019). \u003c/li\u003e\n\u003cli\u003eYan, H. J. \u003cem\u003eet al.\u003c/em\u003e\u003cem\u003e \u003c/em\u003eHoley reduced graphene oxide coupled with an Mo\u003csub\u003e2\u003c/sub\u003eN\u0026ndash;Mo\u003csub\u003e2\u003c/sub\u003eC heterojunction for efficient hydrogen evolution. \u003cem\u003eAdv. Mater. \u003c/em\u003e\u003cstrong\u003e30\u003c/strong\u003e, 1704156 (2018).\u003c/li\u003e\n\u003cli\u003eJun, W. \u003cem\u003eet al\u003c/em\u003e\u003cem\u003e. \u003c/em\u003eStructure confined porous Mo\u003csub\u003e2\u003c/sub\u003eC for efficient hydrogen evolution.\u003cem\u003e Adv. Funct. Mater.\u003c/em\u003e \u003cstrong\u003e27\u003c/strong\u003e, 1703933 (2017).\u003c/li\u003e\n\u003cli\u003eLyu, F. C.\u003cem\u003e et al.\u003c/em\u003e Lamellarly stacking porous N, P co-doped Mo\u003csub\u003e2\u003c/sub\u003eC/C Nanosheets as high performance anode for lithium-ion batteries. \u003cem\u003eSmall \u003c/em\u003e\u003cstrong\u003e15\u003c/strong\u003e, 1805022 (2019).\u003c/li\u003e\n\u003cli\u003eDinh, C. T. \u003cem\u003eet al.\u003c/em\u003e Multi-site electrocatalysts for hydrogen evolution in neutral media by destabilization of water molecules. \u003cem\u003eNat. Energy\u003c/em\u003e \u003cstrong\u003e4\u003c/strong\u003e, 107\u0026ndash;114 (2019).\u003c/li\u003e\n\u003cli\u003eZhou, Z. \u003cem\u003eet al.\u003c/em\u003e Big to Small: Ultrafine Mo\u003csub\u003e2\u003c/sub\u003eC particles derived from giant polyoxomolybdate clusters for hydrogen evolution reaction. \u003cem\u003eSmall\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 1900358 (2019).\u003c/li\u003e\n\u003cli\u003eLuo, Y. \u003cem\u003eet al.\u003c/em\u003e Morphology and surface chemistry engineering toward pH-universal catalysts for hydrogen evolution at high current density. \u003cem\u003eNat. Commun.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 269 (2019).\u003c/li\u003e\n\u003cli\u003eLiu, D. \u003cem\u003eet al\u003c/em\u003e. Atomically dispersed platinum supported on curved carbon supports for efficient electrocatalytic hydrogen evolution. \u003cem\u003eNat. Energy\u003c/em\u003e \u003cstrong\u003e4\u003c/strong\u003e, 512\u0026ndash;518 (2019).\u003c/li\u003e\n\u003cli\u003eFang, S. \u003cem\u003eet al\u003c/em\u003e. Uncovering near-free platinum single-atom dynamics during electrochemical hydrogen evolution reaction. \u003cem\u003eNat. Commun\u003c/em\u003e. \u003cstrong\u003e11\u003c/strong\u003e, 1029 (2020).\u003c/li\u003e\n\u003cli\u003eZhang, J. \u003cem\u003eet al\u003c/em\u003e. Single platinum atoms immobilized on an MXene as an efficient catalyst for the hydrogen evolution reaction. \u003cem\u003eNat. Catal.\u003c/em\u003e \u003cstrong\u003e1\u003c/strong\u003e, 985\u0026ndash;992 (2018).\u003c/li\u003e\n\u003cli\u003eChen, Y. L. \u003cem\u003eet al\u003c/em\u003e. Ultrafast self-heating synthesis of robust heterogeneous nanocarbides for high current density hydrogen evolution reaction. \u003cem\u003eNat. Commun.\u003c/em\u003e \u003cstrong\u003e13\u003c/strong\u003e, 3338 (2022).\u003c/li\u003e\n\u003cli\u003eWang, Z. Y. \u003cem\u003eet al\u003c/em\u003e. Manipulation on active electronic states of metastable phase \u0026beta;-NiMoO\u003csub\u003e4 \u003c/sub\u003efor large current density hydrogen evolution. \u003cem\u003eNat. Commun. \u003c/em\u003e\u003cstrong\u003e12\u003c/strong\u003e, 5960 (2021).\u003c/li\u003e\n\u003cli\u003eGao, S. \u003cem\u003eet al.\u003c/em\u003e Partially oxidized atomic cobalt layers for carbon dioxide electroreduction to liquid fuel. \u003cem\u003eNature\u003c/em\u003e \u003cstrong\u003e529\u003c/strong\u003e, 68 (2016).\u003c/li\u003e\n\u003cli\u003eWang, D. \u003cem\u003eet al\u003c/em\u003e. Atomic and electronic modulation of self-supported nickel-vanadium layered double hydroxide to accelerate water splitting kinetics. \u003cem\u003eNat. Commun.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 3899 (2019).\u003c/li\u003e\n\u003cli\u003eNong, H. N.\u003cem\u003e et al.\u003c/em\u003e Key role of chemistry versus bias in electrocatalytic oxygen evolution. \u003cem\u003eNature \u003c/em\u003e\u003cstrong\u003e587\u003c/strong\u003e, 408-413 (2020).\u003c/li\u003e\n\u003cli\u003eDai, Y. W.\u003cem\u003e et al.\u003c/em\u003e\u003cem\u003e \u003c/em\u003eBridging the charge accumulation and high reaction order for high-rate oxygen evolution and long stable Zn-Air batteries. Adv.\u003cem\u003e Funct. Mater.\u003c/em\u003e\u003cem\u003e \u003c/em\u003e\u003cstrong\u003e32\u003c/strong\u003e, 2111989 (2022).\u003c/li\u003e\n\u003cli\u003eShen, L. F. \u003cem\u003eet al. \u003c/em\u003eInterfacial structure of water as a new descriptor of the hydrogen evolution reaction. Angew. Chem. Int. Ed. \u003cstrong\u003e59\u003c/strong\u003e, 22397\u0026ndash;22402 (2020).\u003c/li\u003e\n\u003cli\u003eZhang, J. \u003cem\u003eet al\u003c/em\u003e. Efficient hydrogen production on MoNi\u003csub\u003e4 \u003c/sub\u003eelectrocatalysts with fast water dissociation kinetics. \u003cem\u003eNat. Commun. \u003c/em\u003e\u003cstrong\u003e8\u003c/strong\u003e, 15437 (2017).\u003c/li\u003e\n\u003cli\u003eZhang, H. C.\u003cem\u003e et al.\u003c/em\u003e Electrochemical recognition of alkylimidazolium-mediated ultrafast charge transfer on graphene surfaces. \u003cem\u003eChem. Commun.\u003c/em\u003e \u003cstrong\u003e54\u003c/strong\u003e, 666 (2018).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-2441531/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2441531/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe site-blocking effect (SBE) of nonelectro-chemical steps (nonECS) gives the sluggish kinetics in alkaline hydrogen evolution reaction (HER), but remains rather challenging in electrocatalysis. Herein, we explored nonECS on the highly amorphized NiMoN/NC(500-R) nanoarrays, in which Ni\u003csub\u003e0.76\u003c/sub\u003eMo\u003csub\u003e1.24\u003c/sub\u003e and Mo\u003csub\u003e2\u003c/sub\u003eN with the crystallinity of only 13.3% were embedded into nitrogen-rich derived carbons (NC) at 500\u003csup\u003eo\u003c/sup\u003eC, then followed by electrochemical surface reconstruction. The amorphization and hydroxylation induce the coupled dual-centers of Ni-Mo species to circumvent SBE through separating H*- and H\u003csub\u003e2\u003c/sub\u003e-involved elementary steps from nonECS, and deliver efficient transfer of individual species and heavy charge accumulation to actuate the whole HER. Resultantly, the exceptional catalytic activity is demonstrated by ultra-low overpotentials of 5.8 and 200.6mV at 10 and 1000mA cm\u003csup\u003e-2\u003c/sup\u003e, respectively. Importantly, NiMoN/NC(500-R) survive in lasting alkaline HER for 50 days at 500mA cm\u003csup\u003e-2\u003c/sup\u003e almost without degeneration. This work presents the key to get rid of SBE in electrocatalysis, and the inspiration to rationally design the amorphized nanoarrays of electrocatalysts.\u003c/p\u003e","manuscriptTitle":"Hydroxylation-Inducing the Coupled Dual-Centers in Highly Amorphized Ni0.76Mo1.24/Mo2N Nanoarrays with Superior Alkaline Hydrogen Evolution","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-01-19 21:32:22","doi":"10.21203/rs.3.rs-2441531/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cf75fea8-f252-4560-810d-bfa35cc7cdb4","owner":[],"postedDate":"January 19th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":18526676,"name":"Physical sciences/Chemistry/Electrochemistry/Electrocatalysis"},{"id":18526677,"name":"Physical sciences/Materials science/Materials for energy and catalysis/Electrocatalysis"},{"id":18526678,"name":"Physical sciences/Engineering/Chemical engineering"},{"id":18526679,"name":"Physical sciences/Materials science/Nanoscale materials/Structural properties"}],"tags":[],"updatedAt":"2023-02-16T09:21:01+00:00","versionOfRecord":[],"versionCreatedAt":"2023-01-19 21:32:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-2441531","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2441531","identity":"rs-2441531","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}