Development and Comprehensive Analysis of rGO/Co3O4@Ni nanocomposite: Dual-Functional Materials for Magnetic and Supercapacitor Applications

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Ghfar, Naresh Kumar Reddy P This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5852230/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract This work involved the hydrothermal synthesis of rGO/Co 3 O 4 @Ni nanocomposites at low temperatures, followed by annealing at 600°C. The microstructural and electrochemical characteristics of the nanostructured rGO/Co 3 O 4 @Ni were evaluated in detail. A Co 3 O 4 cubic structure with the space group Fd̅3m(227) and distinct peaks at the (220), (311), (222), (400), (422), (511), and (440) planes was formed, according to XRD analysis. Raman measurements confirmed the presence of Co-O bonds and provided detailed information on the microstructure of the samples. SEM analysis of the shape and surface architecture demonstrated the unique properties of the porous nanoparticles. The existence of Co 2+ and Co 3+ ions was verified by XPS. The nanocomposites demonstrated improved electrochemical stability and a peak capacitance of 1056 F/g at a current density of 1 A/g in electrochemical tests carried out in an aqueous 1M KOH electrolyte. Energy Storage Supercapacitors Hydrothermal method Electrochemistry Magnetic properties Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 1. Introduction Future generations will require advances in energy storage and conversion materials due to the growing issues encountered by the electrical industries as a result of environmental degradation and rising energy demands [ 1 , 2 ]. Within this framework, supercapacitors emerge as superior alternatives to batteries due to their elevated energy density, efficient charge-discharge abilities, and extended lifespan [ 3 , 4 ]. The performance of supercapacitors is largely governed by the interaction between the electrolyte and electrode materials, which dictate their energy storage and release capacities. Compared to bulk materials, low-dimensional materials are preferable due to their reduced ion diffusion distances, enhanced defect tolerance, phase stability, and potential for novel chemical properties [ 5 ]. Transition metal oxides at the nanoscale, including RuO 2 , MnO 2 , V 2 O 5 , NiO, Mn 3 O 4 , and Co 3 O 4 , have shown promise as effective supercapacitors. Among these, RuO 2 stands out as the optimal electrode material, although its use is limited by toxicity and high cost [ 6 ]. Cobalt oxide has emerged as an alternative electrode material for supercapacitors because of its lower cost, lower hazard, greater stability in alkaline media and innately high theoretical capacity [ 7 ]. Because of its enhanced electrochemical and gas sensing capabilities, Co 3 O 4 is one of the most extensively utilized cobalt compounds because it has an excellent combination of oxidation states. In addition, it is safer due to its spinel structure, resistance to corrosion, and long-term performance [ 8 ]. This material can be utilized for diverse applications including sensor technology, ceramic pigments, solar energy absorption, anode fabrication, magnetic substances, among others. Nevertheless, the deployment of Co 3 O 4 as an electrode for energy applications and as a magnetic component in memory systems presents minimal challenges. Co 3 O 4 has low electrical conductivity [ 9 ], a greater capacity fading during cycling [ 10 ], and its specific capacitance and rate capability are further reduced when a binder is used to keep it on the current collector or substrate. Actually, the binder increases the dead volume and provides more contact resistance between the active material and the current collector by hiding a number of the Co 3 O 4 's redox-active sites [ 11 ]. To improve the specific capacitance and rate capability, nanostructured Co 3 O 4 with a greater surface/volume ratio and smaller particle size can be fabricated [ 12 ]. This would shorten the diffusion path and reduce dead surface area. Unfortunately, because of their increased surface energy, Co 3 O 4 nanoparticles are less likely to aggregate. Material that has been clumped together has a smaller surface area, greater diffusion hesitancy, and a bulky appearance. To inhibit the agglomeration of their NPs, the creation of a Co 3 O 4 nanocomposite using 2D layered rGO appears to be a very successful strategy [ 13 ]. The three-dimensional nickel foam adorned with rGO/Co 3 O 4 nanocomposite features a binder-free architecture, significantly diminishing intrinsic resistance and dead volume [ 14 ]. The electrical properties of Co 3 O 4 nanoparticles can be enhanced extrinsically through the formation of composites with highly conductive matrices, such as conductive polymers, graphene components, activated carbon, carbon nanotubes (CNTs), and similar materials [ 15 ]. To harness the synergistic advantages of two chemically distinct electrode materials, a composite material must be synthesized. A composite is a physical combination that preserves the characteristics of two or more distinct species [ 16 ]. Presently, the focus of study is on developing binary composite TMOs that are combined with carbonaceous matrices in order to enhance characteristics of electrode material. For instance, Electrospun Co₃O₄/PAN-based carbon nanofiber composites have demonstrated excellent electrochemical properties, with a maximum specific capacitance of 341.61 F/g at a scan rate of 10 mV/s, significantly outperforming traditional PAN CNF-based electrodes [ 17 , 18 ]. Similarly, hydrothermally deposited Ni•Co LDH/rGO nanocomposites on nickel foam achieved a specific capacitance of 2702 F/g at 0.25 A/g, retaining 98% of their capacitance after 5000 cycles, highlighting their exceptional cyclic stability [ 19 ]. The integration of metal oxide composites with 2D materials, such as MXene, has also shown promise. For instance, nickel hydroxide composites with MXene exhibited a remarkable capacitance of 675 F/g at 2 A/g, illustrating the potential of composite materials to improve supercapacitor performance [ 20 ]. Microwave-assisted synthesis of gadolinium/cerium oxide nanocomposites has further demonstrated their potential for high-performance supercapacitors, achieving a maximum specific capacitance of 396 F/g at 1 A/g for a 20%-mixed Gd sample [ 21 ]. Furthermore, nanocomposites combining 2D WS₂ and 1D polyaniline (PANI) achieved a capacitance of 464 F/g at 10 mV/s, with outstanding stability. These devices also demonstrated an energy density of 12.9 Wh/kg and power density of 395 W/kg, retaining 67% of their capacitance after 10,000 cycles [ 22 ]. Vimuna et al. synthesized the rGO/MnO 2 composite for use in supercapacitors by irradiating it with microwaves, and they recorded 140.3 F/g specific capacitance at 1 A/g current density [ 23 ]. The TiO 2 /r-GO nanocomposite was made by Sundriyal et al. using a single-step hydrothermal method and demonstrated 1565 F/g specific capacitance at 3 A/g current density with following 1000 cycles of testing, 87% of the initial capacitance [ 24 ]. Fe 2 O 3 /r-GO nanocomposite was synthesized by Devi et al. using a one step chemical reduction method for supercapacitor applications. After 1000 cyclic testing, their manufactured electro-active material showed high capacitive retention with a specific capacitance of 416 F/g at 1 A/g current density [ 25 ]. A NiO/r-GO nanocomposite electrode material with exceptional capacitance of 1093 F/g @1 A/g in a 6 M aqueous KOH solution was recently created by Zhang et al. [ 26 ]. Furthermore, there has been little systematic investigation into the 3D architectures of rGO/Co 3 O 4 @Ni nanocomposite. The annealing temperature is an important factor that influences the microstructure [ 27 , 28 ]. This study focuses on the synthesis of rGO/Co 3 O 4 @Ni nanocomposites employing a straight forward hydrothermal technique. Examining the effects of annealing on the surface architecture and electrochemical characteristics of the nanocomposites through in-depth experimental investigations is a crucial component of this research. Additionally, this work elucidates the magnetic properties of the fabricated rGO/Co 3 O 4 @Ni nanocomposites, providing insights into their potential multifunctional applications, as discussed in the manuscript. 2. Experimental All precursors were utilized as received without additional refinement. Initially, 30 mL of H 2 O is mixed in equal parts with beginning ingredients Cobalt cloride hexahydrated (CoCl 2 .6H 2 O) and sodium hydroxide (NaOH) and spun indefinitely for half an hour and 25 mg of GO was dissolved in 30 mL of C 2 H 5 OH and proceed for ultrasonication for 180 min. (Sonication parameters include a power range of 50–200 W, controlled temperature (20–50°C), and pulse mode to ensure uniform dispersion and improve conductivity for rGO/Co₃O₄ composite synthesis) The initial precursor blend was agitated continuously and independently for one hour, then relocated to a 100 mL Teflon-coated stainless steel autoclave, where it was subjected to a temperature of 200 ºC for 12 hours. Subsequently, the resultant product underwent filtration, was rinsed with ethanol, and dried under vacuum conditions at 100°C for a duration of 24 hours. A 2.5 × 2.5 cm piece of Ni foam was immersed in the solution, and the autoclave was heated to 150°C in a furnace for 12 hours. Following the heat treatment, the furnace was permitted to gradually return to ambient temperature. The resulting rGO/Co 3 O 4 -coated Ni foam sample was thoroughly cleaned with ethanol and deionized water before drying overnight at 80°C. The sample was then annealed at 600°C for four hours before being sent for characterisation. Figure 1 displays a schematic illustration of the synthesis procedure used to produce rGO/Co 3 O 4 @Ni nanocomposite electrodes. The sample was collected and systematically analyzed to determine its structural, morphological, and electrochemical properties. Several characterisation approaches were used, as described in Table 1 . Table 1 Characterization techniques S. No. Properties studied Type of characterization Instrument 1 Structural X-Ray Diffraction (XRD) CuKα (λ = 0.154 nm) radiation source fltered by Ni thin flm at a scan speed of 0.05° per second in the 2θ range 20–70° 2 Functional groups Raman Spectroscopy Raman Spectroscopy using Horiba Jobin Yvon Lab RAM HR800UV Raman spectrometer in the range 200–2000 cm − 1 3 Morphology Scanning electron microscopy (SEM) Carl ZEISS (Model EVO MA15) morphology and chemical composition of the sample in high vacuum 4 Chemical composition Energy-dispersive spectroscopy (EDS) EDS system (Oxford Instruments, UK) the chemical analysis of the sample He–Ne laser 532 nm as an excitation wavelength X-Ray Photo electron Spectroscopy (XPS) The survey along with core-level high resolution spectra are measured using a monochromatic Al Kα X-ray (1486.6 eV) at the vacuum level of 10 − 9 Torr, an applied beam current of 9 mA and acceleration voltage of 13 keV (117 W) 5 Surface area, pore size and volume distribution BET and BJH analysis BELSORP-maxII 6 Mass reduction TGA studies Discovery TGA 5500 7 FC, ZFC and Hysteresis Magnetic properties Vibrating Sample Magnetometer 8 Electrochemical properties Cyclic voltammetry, Chronopotentiometry and Electrochemical Impedance Spectroscopy (EIS) CHI608 instrument 3. RESULTS AND DISCUSSION 3.1 XRD studies The structure of rGO/Co 3 O 4 @Ni nanocomposite was investigated using powder XRD with diffraction angle ranging from 20° to 70°. Figure 2 shows the diffraction spectra of as synthesized and annealed rGO/Co 3 O 4 @Ni nanocomposite. The XRD results revealed that the (311) peak is the dominant alignment at 2θ = 37.17° in both samples. The development of crystalline rGO/Co 3 O 4 @Ni nanocomposite is suggested by other planes (220), (222), (400), (422), (333), and (440) (*Nickel). The XRD examination indicates that Co 3 O 4 has a cubic crystal structure, which is consistent with prior research [ 29 , 30 ]. Significantly, the XRD spectrum of the as-prepared sample displays a low intensity that escalates with temperature, suggesting an enhancement in the sample's crystallinity as the temperature increases. Additionally, there is a shift in the 2θ angle and a marked augmentation in crystallite size corresponding to higher annealing temperatures. According to Scherrer's formula, as-prepared and annealed samples have crystallite sizes of 20 and 25 nm, respectively. 3.2 Raman studies Further, the crystal structure of the rGO/Co 3 O 4 @Ni nanocomposite was further investigated by Raman spectroscopy. The Raman studies of nanocmposites were collected in the 200–1600 cm − 1 range to look into how the temperature affects the samples' vibrational modes (Fig. 3 ). The A 1g mode corresponds to the pronounced intensity observed at 687 cm − 1 , the F 2g mode is attributed to the central weak intensity noted at 521 cm − 1 , and E g mode is associated with the Raman band displaying medium intensity situated at 479 cm − 1 . The existence of a peak at 686 cm − 1 is specifically with the Co-O breathing vibration of Co 2+ ions in tetrahedral coordination. The Raman results supporting and validating the XRD results. The Raman active mode shifts by approximately 2 cm − 1 after annealing the rGO/Co 3 O 4 @Ni nanocomposite, indicating the influence of particle size. This modification has been correlated with enhancements in particle nature and structural organization, aligning well with previous observations [ 30 ]. The Raman spectra presented in Fig. 3 b (the closest view) shows that all carbon compounds have the most abundant D and G bands. The G band arises from the in-plane stretching vibrations of sp2-bonded carbon atoms. The D band, typically associated with disorder, is attributed to edge effects, dangling sp2 carbon bonds, and structural defects that disrupt the symmetry. For GO, the centroid of the D and G bands is situated at 1458 and 1520 cm − 1 , respectively [ 31 ]. 3.3 SEM and EDS Studies The surface morphology of the samples were assessed via SEM examination. Figure 4 depicts SEM images of rGO/Co 3 O 4 @Ni nanocomposites. Figure 4 a,b,c, and d show as-synthesized rGO/Co 3 O 4 @Ni nanocomposite at various magnifications. As illustrated in Fig. 4 d, the sample surface appears as agglomerated non-uniform spherical shaped grains with an average grain size of 150 nm. This surface feature significantly enhances the material's electrochemical properties. The surface area that is available for electrochemical reactions is increased by a porous texture, resulting in faster rates of ion exchange and electron transfer. Effective material interaction at the electrochemical interface is crucial for applications in energy storage and catalysis, making these properties fundamental. Additionally, the detection of some spheres exhibiting uniform surface architecture, while others display non-uniformity across all spheres, indicates that the synthesis process of the rGO/Co 3 O 4 @Ni nanocomposite necessitates further refinement of the processing parameters. Following further annealing of the sample, there is a little propensity for the spheres to cluster together on their surfaces (Fig. 4 f). Uniformity in surface structure is indicative of a fully developed composite, essential for ensuring the material’s performance and functional properties in various applications. EDS was also used to quantify the samples' elemental composition. Focusing on and covering different sections of the samples, the EDS measurements were carefully carried out to guarantee complete and accurate results. This method produced a representative elemental analysis and assisted in mitigating any local compositional differences. The obtained spectra are shown in Fig. 5 and show different peaks according to the components present. A table that summarizes the atomic percentages of carbon (C), oxygen (O), and cobalt (Co) for every sample is also included, making it easier to compare the elemental makeup of the various samples in detail. 3.4 XPS studies XPS investigations were carried out to look into the elemental composition and chemical states of annealed rGO/Co 3 O 4 @Ni nanocomposite. The carbon component in the sample is displayed in the C1s spectrum in Fig. 6 a. The O1s spectrum, which is shown in Fig. 6 b, is a crucial tool for understanding the compound's oxygen environment. The Co 2P spectrum, as shown in Fig. 6 c, offers important information on the Co states that are present in the material. The spectrum clearly shows two distinct peaks that correspond to the Co 2p 3/2 and Co 2p 1/2 orbital levels, with binding energies of 780 eV and 796.5 eV, respectively [ 32 ]. The physical evidence provided by the observed peaks supports the presence of a spinel structure and thus the + 2 and + 3 oxidation states of cobalt. In addition to supporting the identification of the spinel phase of Co 3 O 4 , the current analysis indicates the termination of the spinel surface, indicating a specific orientation consistent with the stabilization of Co 2+ and Co 3+ species at the surface. Thermal gravimetric analysis (TGA) is a technique that quantifies the changes in a material’s physical and chemical properties either over time at a constant temperature and/or mass loss, or as temperature increases at a constant heating rate. Their TGA further validated the rGO/Co 3 O 4 nanocomposite's percentage composition and thermal stability. The thermogravimetric profiles of the pristine and heat-treated samples are displayed in Fig. 7 . The sample as prepared shows a 4% weight drop, which is explained by the removal of physically adsorbed water content [ 33 ]. By contrast, an extra 20% of weight is lost in the annealed sample. The plot indicates that the initial stage of decomposition was observed up to 200°C, which is most likely connected to the evaporation of leftover H 2 O (about 5%). The second weight loss occurred between 200 and 600 degrees Celsius, a temperature range linked to chemical processes such dehydration, deterioration, and condensation as well as the heat-induced breakdown of materials. This stage is characterized by a loss of aliphatic character that simultaneously releases gas and increases aromaticity. A significant weight loss is seen above 700°C, indicating that the material has undergone significant breakdown. 3.5 BET and BJH studies Figure 8 shows the BET surface area analysis of the annealed sample revealed a surface area of 1.0612 m²/g. This relatively high surface area contributes to the enhanced electrochemical performance of the material. Furthermore, the BJH analysis indicated a pore diameter of 1.76 nm and a pore volume of 0.00025 cm³/g for the annealed sample. These structural properties suggest that the material is well-suited for applications requiring efficient energy storage and improved electrochemical behavior. 3.6 Electrochemical studies Using a variety of electroanalytical techniques, the electrochemical characteristics of the as-prepared and annealed rGO/Co 3 O 4 @Ni nanocomposite are investigated. The three main analytical techniques used in these studies are EIS, CP, and CV in a three-electrode glass cell setup (the electrodes are presented in Table 2 ). The purpose of this work is to determine how the annealing procedure affects the rGO/Co 3 O 4 @Ni nanocomposite electrochemical performance. Table 2 List of electrodes S.No. Name of the electrode Material used 1 Working electrode Annealed rGO/Co 3 O 4 @Ni 2 Reference electrode Ag/AgCl 3 Counter electrode Platinum foil 4 Electrolyte 1M KOH CV provides insights into the redox properties of nanomaterials by monitoring the current resulting from electrochemical reactions as a function of applied voltage. This method indicates possible modifications in the electronic structure after annealing and aids in comprehending the oxidative and reductive properties of the nanoparticles. The CV micrographs of the annealed rGO/Co 3 O 4 @Ni nanocomposite in various potential windows are displayed in Fig. 9 a at scan rate of 10 mV/s. The sample is seen to exhibit larger area between − 0.1 and 1.0 V. As a result, further CV research is done in the window at various scan rates, as seen in Fig. 9 b. It can be seen from Fig. 9 b that when scan rate increases, the loop size of the CV curve decreases which indicate the lower in specific capacitance with increase in scan rate [ 34 ]. To calculate specific capacitance, the formula typically used is [ 35 , 36 ] : \(\:\text{C}=\:\frac{\int\:\:\text{I}\:\left(\text{V}\right)\text{d}\text{V}}{2\text{m}(\text{V}2\:-\:\text{V}1){\Delta\:}\text{V}}\) (F/g) ------(1) Here, Symbol Parameter Unit C specific capacitance Farad gram − 1 I (V) instantaneous current ampere ∫I (V) dV total voltametric charge coulomb m mass of active material (5.59 x 10 − 4 ) gram ΔV scan rate volt second − 1 V2-V1 potential window volt The annealed sample showed the specific capacitance values of 602, 567, 501, 434, 387, 311, 267, 210, 176 F/g at a scan rate of 1, 2, 5, 10, 20, 50, 100, 200 and 300 mV/s in a 1M KOH aqueous solution respectively, according to the equation above. The measure values are greater than those already reported for rGO-Co 3 O 4 nanocomposite which was carried out in 1M H 2 SO 4 which indicates the aqueous alkaline electrolytes are better for TMO composites [ 37 , 38 ] The charge-discharge rates of the nanocomposites can be examined using a technique called chromatopotentiometry (CP), in which the current is maintained constant while the potential changes are monitored. Because annealing can cause structural changes, this approach is especially helpful for assessing the kinetic aspects of the electrode processes. The annealed rGO/Co 3 O 4 @Ni nanocomposite charge discharge curves employing the galvanostatic charge-discharge (GCD) technique are shown in Fig. 8 c at different current densities of 1, 2, 3 and 5 A/g. The charge-discharge curves are extremely symmetrical which suggests electrochemical reversibility of the nanocomposite [ 39 , 40 ]. The specific capacitance values of the sample was calculated from charge-discharge curves using the following formula and [ 35 , 36 ] and are presented in the following Table 2 . \(\:C=\:\frac{I\:\varDelta\:t}{m\varDelta\:V}\) (F/g) ------(2) Here, Symbol Parameter Unit C specific capacitance farad gram − 1 I galvanostatic discharge current ampere Δt discharge time second m mass of active material (5.59 x 10 − 4 ) gram ΔV voltage range volt Table 2 Specific capacitance of the samples at different current densities Sample Current Density (A/g) Specific Capacitance (F/g) Annealed 1 1056 2 896 3 678 5 456 The annealed sample's cyclic consistency is examined and shown in Fig. 9 d. The sample's capacitive retention at a current density of 5 A/g after 5000 consecutive cycles is shown in Fig. 9 d. After 5000 cycles, the annealed rGO/Co 3 O 4 @Ni nanocomposite maintained 75% capacitance, suggesting a long cycle life. SEM images showed that the sample's unique morphology and low aggregation states may have contributed to its greatest capacitive retention. This suggests that due of the strong particle interactions, the active material is also integrated during the cycles. The Nickel foam, XRD spectrum and SEM micrographs are shown in the inset of Fig. 9 d. Figure 9 e showed the first 50 cycles of charge-discharge to understand the polarization of the polarization charge during the cycling. In addition, Fig. 9 f showed the first and last 5 charge-discharge cycles to understand the symmetry of the cycles and columbic efficiency of the sample. It is observed 100% columbic efficiency after 1000 cycles. The obtained results were compared with the already reported work as given in the Table 3 . It is to be noted that the sample’s leakage current values were found to be less than 5 µA, indicating high quality and stability and exhibited a self-discharge time of approximately 24 hours, with only a 18% drop in voltage during this period. Table 3 Results comparison S.No. Material Method of Preparation Specific Capacitance (F/g) Capacitive retention (%) Cycles Reference 1 Co 3 O 4 /rGO/CNTs nanocomposite hydrothermal method 790 F g − 1 at 1 A g − 1 73 2000 [ 41 ] 2 P-Co 3 O 4 /RGO Phosphating treatment 448 F g − 1 at 1 A g − 1 78 5000 [ 42 ] 3 RGO-Co 3 O 4 -PPy composite films hydrothermal method 532.8 F g -1 at 0.2 A g − 1 100 700 [ 43 ] 4 Co 3 O 4 /rGO nanocomposites hydrothermal method 754 Fg − 1 96 1000 [ 44 ] 5 Co 3 O 4 /reduced graphene oxide (rGO) composite hydrothermal method 916.6 F g − 1 at 0.5 A g − 1 98 1000 [ 45 ] 6 RGO/Co 3 O 4 Composites coprecipitation method 546 F g − 1 at 1 A g − 1 90 10000 [ 46 ] 7 Co 3 O 4 /r-GO nanocomposite hydrothermal routes 865 Fg − 1 @ 1 Ag − 1 93.2 5000 [ 47 ] 8 rGO/Co 3 O 4 @Ni nanocomposite Hydrothermal method 1056 Fg − 1 at 1 A g − 1 75 5000 Present work The Nyquist plot was obtained for annealed rGO/Co 3 O 4 @Ni nanocomposite using electrochemical impedance spectroscopy (EIS) in the frequency range of 1 Hz to 1 MHz shown in Fig. 9 g&h. The Nyquist plot indicates the semicircle in the high-frequency region while the straight line is in the low-frequency region. The Nyquist plot intercepting at x intercept gives the internal resistance (Rs) of 1.3 Ω. While the diameter of semicircles gives the charge transfer resistance (Rct) which was 2.2 Ω. 3.7 Magnetic studies Figure 10 illustrates the temperature dependence of magnetization under zero-field cooled (ZFC) and field-cooled (FC) conditions. A subtle peak around 50 K characterizes the ZFC curve, and significant divergence between the ZFC and FC curves emerges at lower temperatures. Specifically, at 5 K, the magnetization in the FC scenario is nearly twice that observed in the ZFC condition. For temperatures above 60 K, the magnetization curve becomes linear, aligning with the Curie-Weiss law. The estimated effective magnetic moment per ion in the paramagnetic phase is approximately 4.35 µB, which is in agreement with previous findings. Figure 11 subsequently details the magnetic properties of rGO/Co 3 O 4 @Ni nanocomposite at temperatures of 5 K and 300 K. As shown in Fig. 11 , the hysteresis curve of as-prepared rGO/Co 3 O 4 @Ni nanocomposite exhibits ferromagnetic behavior at all temperatures spanning from 5 K to 100 K, although the saturation magnetization was found to drop from 0.913 to 0.621 emu/g. The sample's ferromagnetic behavior can be related to uncompensated surface spins and limited size effects [ 48 ]. Materials possessing both supercapacitive and magnetic properties present significant utility in the realm of advanced technological applications, due to their dual functionality which enables innovative solutions across diverse sectors such as electronics, energy storage systems, and biomedical engineering. The integration of supercapacitive behavior facilitates rapid charge and discharge cycles, high power density, and efficient energy storage capabilities. Concurrently, the intrinsic magnetic properties of these materials allow for manipulation and control using external magnetic fields, enhancing their applicability in magnetic sensors, actuators, and targeted delivery systems in medical applications. 4. Conclusion The rGO/Co 3 O 4 @Ni nanocomposite was synthesized using a straightforward hydrothermal method at 200°C, followed by vacuum annealing at 600°C to optimize its properties for supercapacitor applications. Characterization through XRD and Raman spectroscopy confirmed the cubic crystal structure of the nanocomposite, while SEM analyses demonstrated that the morphology was consistently influenced by the annealing temperature. Notably, the annealed samples exhibited a complete formation of the nanocomposite structure. Electrochemical testing revealed that the annealed rGO/Co 3 O 4 @Ni nanocomposite electrodes achieved a peak specific capacitance of 1056 F/g at a current density of 1 A/g using an aqueous 1M KOH electrolyte. Furthermore, after 5000 charge-discharge cycles at 5 A/g, the electrodes retained 75% of their initial capacitance, indicating robust electrochemical stability. This study underscores the necessity of optimizing the annealing process to enhance the surface area and morphological features of the nanocomposites, which are crucial for maximizing their electrochemical performance. Notably, they maintained a significant proportion of their initial capacitance after 5000 cycles, underscoring their potential for high-performance energy storage applications. Additionally, the magnetic properties of the nanocomposites suggest potential applications in magnetic memory devices, benefitting from their exhibited ferromagnetic behaviour. Declarations -Authors Contributions Dr. Dadamiah PMD Shaik: Writing – review & editing, Writing – original draft, Methodology, Funding acquisition, Formal analysis, Data curation. Rosaiah Pitcheri: Writing – review & editing, Writing – original draft, Methodology, Formal analysis, Data curation. Ayman A. Ghfar: Writing – review & editing, Formal analysis, Data curation, Conceptualization-Funding, Naresh Kumar Reddy P: Writing – review & editing, Formal Analysis. -Competing Interests- Not applicable -Funding: This work is funded by King Saud University, Saudi Arabia -Data availability: Data will be available on request Ethics, Consent to Participate, and Consent to Publish declarations: not applicable. clinical trial declarations: not applicable Acknowledgement: The authors are greatful to the Researchers Supporting Project number (RSP2025R407), King Saud University, Riyadh, Saudi Arabia for the financial support. References Rosaiah, P., Yue, D., Dayanidhi, K., Ramachandran, K., Vadivel, P., Sheik Eusuff, N., Minnam Reddy, V.R., Kim, W.K. 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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-5852230","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":449196960,"identity":"66adcfd3-1e83-4f8a-9286-a75b61c94f16","order_by":0,"name":"Dadamiah PMD Shaik","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyElEQVRIiWNgGAWjYFACHoYDDxgY5EBMEINILQkMDMZgLQnEamEAqkxsALGJ0mLefvbggYQ/d9Lnhx1+CLTFTk63gYAWmTN5CQcS257lbrydZgDUkmxsdoCAFgmGHIMDiQ2HczfOTgBpOZC4jaAW/jdAlX8OpxvOTv9ApBYJoC0JbIcT5KVziLVFAmgL0C+GG6RzCg4kGBDjF/4c4w8f/tyRl5+dvvnDhwo7OYJaoOAAgwFYpQFxyiFa5BuIVz0KRsEoGAUjDAAAJ7BMhr0kK6wAAAAASUVORK5CYII=","orcid":"","institution":"Vardhaman College of Engineering","correspondingAuthor":true,"prefix":"","firstName":"Dadamiah","middleName":"PMD","lastName":"Shaik","suffix":""},{"id":449196963,"identity":"51c7b39e-044c-4b7f-a529-22d4ccd45999","order_by":1,"name":"Rosaiah Pitcheri","email":"","orcid":"","institution":"Saveetha Institute of Medical and Technical Sciences (SIMATS)","correspondingAuthor":false,"prefix":"","firstName":"Rosaiah","middleName":"","lastName":"Pitcheri","suffix":""},{"id":449196965,"identity":"3eb3dce9-6ac1-4e2a-9301-80355296c501","order_by":2,"name":"Ayman A. 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1","display":"","copyAsset":false,"role":"figure","size":391866,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite preparation\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/e858a17830d6bd4dc8339981.png"},{"id":81611836,"identity":"260c0769-2c50-407e-91f8-98ccdd0da826","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":250073,"visible":true,"origin":"","legend":"\u003cp\u003eXRD spectra of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/250105f2ddaf11dd2c2eecda.png"},{"id":81611838,"identity":"8bf7b6b3-3db0-429a-b3b9-269b802ec3d1","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":257887,"visible":true,"origin":"","legend":"\u003cp\u003ea\u0026amp;b Raman Spectra of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/fefc0883bca2695a3ce0d5c3.png"},{"id":81611841,"identity":"19d27dc0-5526-40e6-93b1-5b06f18e4c86","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":622274,"visible":true,"origin":"","legend":"\u003cp\u003eSEM images of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni \u0026nbsp;nanocomposite a-d) synthesized at different magnifications f) annealed at 600 \u003csup\u003eo\u003c/sup\u003eC\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/cba07f8f90b93959ce2eff1a.png"},{"id":81611861,"identity":"89548f08-a31a-4014-bee8-5836458d019b","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":310415,"visible":true,"origin":"","legend":"\u003cp\u003eEDS spectra of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni \u0026nbsp;nanocomposite a) synthesized b) annealed at 600 \u003csup\u003eO\u003c/sup\u003eC\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/6ae90b96fe1ec13dfb6165ee.png"},{"id":81612058,"identity":"a589e2a3-48f8-42b7-94d0-017d0d5f5221","added_by":"auto","created_at":"2025-04-29 07:34:42","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":302651,"visible":true,"origin":"","legend":"\u003cp\u003eXPS Spectra of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/d34cc838eba3f3715a78af17.png"},{"id":81611843,"identity":"ad8e4649-dea3-4adf-977a-473b8335b70f","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":378116,"visible":true,"origin":"","legend":"\u003cp\u003eTGA spectra\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/b1110d154d862e272a121663.png"},{"id":81612059,"identity":"5ab1f90d-ecb5-4df7-b710-f2db11c5bb62","added_by":"auto","created_at":"2025-04-29 07:34:42","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":285267,"visible":true,"origin":"","legend":"\u003cp\u003eBET and BJH analysis of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/5a0116361720c0beffb79894.png"},{"id":81612991,"identity":"d090972f-0a2e-4d92-9ba9-a29758ffb040","added_by":"auto","created_at":"2025-04-29 07:42:42","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":669499,"visible":true,"origin":"","legend":"\u003cp\u003ea CV curves of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite at different potential windows b) CV curves of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite at different scan rates c) Charge-discharge curves at different current densities d) long term cyclic stability (inset: Nickel form, XRD and SEM after 5000 cycling e) First 50 charge discharge cycles f) First and last five charge-discharge cycles of annealed sample g,h) Nyquist plots before and after 5000 cycling (inset regone plat and equivalent circuit)\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/f5376574d769de102f043051.png"},{"id":81611847,"identity":"010ba7f9-2365-47d4-a7a6-732477b1df0a","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":219932,"visible":true,"origin":"","legend":"\u003cp\u003eMagnetization for ZFC and FC rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite in 50 Oe applied field as function of temperature.\u003c/p\u003e","description":"","filename":"floatimage10.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/1bca1f03ab7fd2f6000b0ee2.png"},{"id":81611852,"identity":"9c3557b7-59eb-46f2-aa3e-690fd4855e8c","added_by":"auto","created_at":"2025-04-29 07:26:42","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":701807,"visible":true,"origin":"","legend":"\u003cp\u003eMagnetization vs Magnetic field of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite\u003c/p\u003e","description":"","filename":"floatimage11.png","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/1b3a6a1e125ef27af2567dcc.png"},{"id":81702196,"identity":"6ead5603-c720-4ead-a5b5-bad1edf1ac88","added_by":"auto","created_at":"2025-04-30 13:09:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5397671,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5852230/v1/532a623a-0796-4cb7-940a-e8d82aec522c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Development and Comprehensive Analysis of rGO/Co3O4@Ni nanocomposite: Dual-Functional Materials for Magnetic and Supercapacitor Applications","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eFuture generations will require advances in energy storage and conversion materials due to the growing issues encountered by the electrical industries as a result of environmental degradation and rising energy demands [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Within this framework, supercapacitors emerge as superior alternatives to batteries due to their elevated energy density, efficient charge-discharge abilities, and extended lifespan [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The performance of supercapacitors is largely governed by the interaction between the electrolyte and electrode materials, which dictate their energy storage and release capacities. Compared to bulk materials, low-dimensional materials are preferable due to their reduced ion diffusion distances, enhanced defect tolerance, phase stability, and potential for novel chemical properties [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Transition metal oxides at the nanoscale, including RuO\u003csub\u003e2\u003c/sub\u003e, MnO\u003csub\u003e2\u003c/sub\u003e, V\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e, NiO, Mn\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e, and Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e, have shown promise as effective supercapacitors. Among these, RuO\u003csub\u003e2\u003c/sub\u003e stands out as the optimal electrode material, although its use is limited by toxicity and high cost [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCobalt oxide has emerged as an alternative electrode material for supercapacitors because of its lower cost, lower hazard, greater stability in alkaline media and innately high theoretical capacity [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Because of its enhanced electrochemical and gas sensing capabilities, Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e is one of the most extensively utilized cobalt compounds because it has an excellent combination of oxidation states. In addition, it is safer due to its spinel structure, resistance to corrosion, and long-term performance [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This material can be utilized for diverse applications including sensor technology, ceramic pigments, solar energy absorption, anode fabrication, magnetic substances, among others.\u003c/p\u003e \u003cp\u003eNevertheless, the deployment of Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e as an electrode for energy applications and as a magnetic component in memory systems presents minimal challenges. Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e has low electrical conductivity [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], a greater capacity fading during cycling [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], and its specific capacitance and rate capability are further reduced when a binder is used to keep it on the current collector or substrate. Actually, the binder increases the dead volume and provides more contact resistance between the active material and the current collector by hiding a number of the Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e's redox-active sites [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo improve the specific capacitance and rate capability, nanostructured Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e with a greater surface/volume ratio and smaller particle size can be fabricated [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. This would shorten the diffusion path and reduce dead surface area. Unfortunately, because of their increased surface energy, Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanoparticles are less likely to aggregate. Material that has been clumped together has a smaller surface area, greater diffusion hesitancy, and a bulky appearance. To inhibit the agglomeration of their NPs, the creation of a Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanocomposite using 2D layered rGO appears to be a very successful strategy [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe three-dimensional nickel foam adorned with rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanocomposite features a binder-free architecture, significantly diminishing intrinsic resistance and dead volume [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. The electrical properties of Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanoparticles can be enhanced extrinsically through the formation of composites with highly conductive matrices, such as conductive polymers, graphene components, activated carbon, carbon nanotubes (CNTs), and similar materials [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. To harness the synergistic advantages of two chemically distinct electrode materials, a composite material must be synthesized. A composite is a physical combination that preserves the characteristics of two or more distinct species [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Presently, the focus of study is on developing binary composite TMOs that are combined with carbonaceous matrices in order to enhance characteristics of electrode material. For instance, Electrospun Co₃O₄/PAN-based carbon nanofiber composites have demonstrated excellent electrochemical properties, with a maximum specific capacitance of 341.61 F/g at a scan rate of 10 mV/s, significantly outperforming traditional PAN CNF-based electrodes [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Similarly, hydrothermally deposited Ni\u0026bull;Co LDH/rGO nanocomposites on nickel foam achieved a specific capacitance of 2702 F/g at 0.25 A/g, retaining 98% of their capacitance after 5000 cycles, highlighting their exceptional cyclic stability [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. The integration of metal oxide composites with 2D materials, such as MXene, has also shown promise. For instance, nickel hydroxide composites with MXene exhibited a remarkable capacitance of 675 F/g at 2 A/g, illustrating the potential of composite materials to improve supercapacitor performance [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Microwave-assisted synthesis of gadolinium/cerium oxide nanocomposites has further demonstrated their potential for high-performance supercapacitors, achieving a maximum specific capacitance of 396 F/g at 1 A/g for a 20%-mixed Gd sample [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Furthermore, nanocomposites combining 2D WS₂ and 1D polyaniline (PANI) achieved a capacitance of 464 F/g at 10 mV/s, with outstanding stability. These devices also demonstrated an energy density of 12.9 Wh/kg and power density of 395 W/kg, retaining 67% of their capacitance after 10,000 cycles [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Vimuna et al. synthesized the rGO/MnO\u003csub\u003e2\u003c/sub\u003e composite for use in supercapacitors by irradiating it with microwaves, and they recorded 140.3 F/g specific capacitance at 1 A/g current density [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The TiO\u003csub\u003e2\u003c/sub\u003e/r-GO nanocomposite was made by Sundriyal et al. using a single-step hydrothermal method and demonstrated 1565 F/g specific capacitance at 3 A/g current density with following 1000 cycles of testing, 87% of the initial capacitance [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Fe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e/r-GO nanocomposite was synthesized by Devi et al. using a one step chemical reduction method for supercapacitor applications. After 1000 cyclic testing, their manufactured electro-active material showed high capacitive retention with a specific capacitance of 416 F/g at 1 A/g current density [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. A NiO/r-GO nanocomposite electrode material with exceptional capacitance of 1093 F/g @1 A/g in a 6 M aqueous KOH solution was recently created by Zhang et al. [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Furthermore, there has been little systematic investigation into the 3D architectures of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite. The annealing temperature is an important factor that influences the microstructure [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study focuses on the synthesis of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposites employing a straight forward hydrothermal technique. Examining the effects of annealing on the surface architecture and electrochemical characteristics of the nanocomposites through in-depth experimental investigations is a crucial component of this research. Additionally, this work elucidates the magnetic properties of the fabricated rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposites, providing insights into their potential multifunctional applications, as discussed in the manuscript.\u003c/p\u003e"},{"header":"2. Experimental","content":"\u003cp\u003eAll precursors were utilized as received without additional refinement. Initially, 30 mL of H\u003csub\u003e2\u003c/sub\u003eO is mixed in equal parts with beginning ingredients Cobalt cloride hexahydrated (CoCl\u003csub\u003e2\u003c/sub\u003e.6H\u003csub\u003e2\u003c/sub\u003eO) and sodium hydroxide (NaOH) and spun indefinitely for half an hour and 25 mg of GO was dissolved in 30 mL of C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eOH and proceed for ultrasonication for 180 min. (Sonication parameters include a power range of 50\u0026ndash;200 W, controlled temperature (20\u0026ndash;50\u0026deg;C), and pulse mode to ensure uniform dispersion and improve conductivity for rGO/Co₃O₄ composite synthesis) The initial precursor blend was agitated continuously and independently for one hour, then relocated to a 100 mL Teflon-coated stainless steel autoclave, where it was subjected to a temperature of 200 \u0026ordm;C for 12 hours. Subsequently, the resultant product underwent filtration, was rinsed with ethanol, and dried under vacuum conditions at 100\u0026deg;C for a duration of 24 hours. A 2.5 \u0026times; 2.5 cm piece of Ni foam was immersed in the solution, and the autoclave was heated to 150\u0026deg;C in a furnace for 12 hours. Following the heat treatment, the furnace was permitted to gradually return to ambient temperature. The resulting rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e-coated Ni foam sample was thoroughly cleaned with ethanol and deionized water before drying overnight at 80\u0026deg;C. The sample was then annealed at 600\u0026deg;C for four hours before being sent for characterisation. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e displays a schematic illustration of the synthesis procedure used to produce rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite electrodes. The sample was collected and systematically analyzed to determine its structural, morphological, and electrochemical properties. Several characterisation approaches were used, as described in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacterization techniques\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS. No.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProperties studied\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eType of characterization\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eInstrument\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eStructural\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eX-Ray Diffraction (XRD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCuKα (λ\u0026thinsp;=\u0026thinsp;0.154\u0026nbsp;nm) radiation source fltered by Ni thin flm at a scan speed of 0.05\u0026deg; per second in the 2θ range 20\u0026ndash;70\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFunctional groups\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRaman Spectroscopy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRaman Spectroscopy using Horiba Jobin Yvon Lab RAM HR800UV Raman spectrometer in the range 200\u0026ndash;2000 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMorphology\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eScanning electron microscopy (SEM)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCarl ZEISS (Model EVO MA15) morphology and chemical composition of the sample in high vacuum\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eChemical composition\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnergy-dispersive spectroscopy (EDS)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eEDS system (Oxford Instruments, UK) the chemical analysis of the sample He\u0026ndash;Ne laser 532\u0026nbsp;nm as an excitation wavelength\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eX-Ray Photo electron Spectroscopy (XPS)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eThe survey along with core-level high resolution spectra are measured using a monochromatic Al Kα X-ray (1486.6 eV) at the vacuum level of 10\u0026thinsp;\u0026minus;\u0026thinsp;9 Torr, an applied beam current of 9 mA and\u003c/p\u003e \u003cp\u003eacceleration voltage of 13 keV (117 W)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurface area, pore size and volume distribution\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBET and BJH analysis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBELSORP-maxII\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMass reduction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTGA studies\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDiscovery TGA 5500\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFC, ZFC and Hysteresis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMagnetic properties\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eVibrating Sample Magnetometer\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eElectrochemical properties\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCyclic voltammetry, Chronopotentiometry and Electrochemical Impedance Spectroscopy (EIS)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCHI608 instrument\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"3. RESULTS AND DISCUSSION","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1 XRD studies\u003c/h2\u003e \u003cp\u003eThe structure of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite was investigated using powder XRD with diffraction angle ranging from 20\u0026deg; to 70\u0026deg;. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the diffraction spectra of as synthesized and annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite. The XRD results revealed that the (311) peak is the dominant alignment at 2θ\u0026thinsp;=\u0026thinsp;37.17\u0026deg; in both samples. The development of crystalline rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite is suggested by other planes (220), (222), (400), (422), (333), and (440) (*Nickel). The XRD examination indicates that Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e has a cubic crystal structure, which is consistent with prior research [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Significantly, the XRD spectrum of the as-prepared sample displays a low intensity that escalates with temperature, suggesting an enhancement in the sample's crystallinity as the temperature increases. Additionally, there is a shift in the 2θ angle and a marked augmentation in crystallite size corresponding to higher annealing temperatures. According to Scherrer's formula, as-prepared and annealed samples have crystallite sizes of 20 and 25 nm, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Raman studies\u003c/h2\u003e \u003cp\u003eFurther, the crystal structure of the rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite was further investigated by Raman spectroscopy. The Raman studies of nanocmposites were collected in the 200\u0026ndash;1600 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e range to look into how the temperature affects the samples' vibrational modes (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The A\u003csub\u003e1g\u003c/sub\u003e mode corresponds to the pronounced intensity observed at 687 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, the F\u003csub\u003e2g\u003c/sub\u003e mode is attributed to the central weak intensity noted at 521 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and E\u003csub\u003eg\u003c/sub\u003e mode is associated with the Raman band displaying medium intensity situated at 479 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The existence of a peak at 686 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e is specifically with the Co-O breathing vibration of Co\u003csup\u003e2+\u003c/sup\u003e ions in tetrahedral coordination. The Raman results supporting and validating the XRD results. The Raman active mode shifts by approximately 2 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e after annealing the rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite, indicating the influence of particle size. This modification has been correlated with enhancements in particle nature and structural organization, aligning well with previous observations [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe Raman spectra presented in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb (the closest view) shows that all carbon compounds have the most abundant D and G bands. The G band arises from the in-plane stretching vibrations of sp2-bonded carbon atoms. The D band, typically associated with disorder, is attributed to edge effects, dangling sp2 carbon bonds, and structural defects that disrupt the symmetry. For GO, the centroid of the D and G bands is situated at 1458 and 1520 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.3 SEM and EDS Studies\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe surface morphology of the samples were assessed via SEM examination. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e depicts SEM images of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposites. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea,b,c, and d show as-synthesized rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite at various magnifications. As illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed, the sample surface appears as agglomerated non-uniform spherical shaped grains with an average grain size of 150 nm. This surface feature significantly enhances the material's electrochemical properties. The surface area that is available for electrochemical reactions is increased by a porous texture, resulting in faster rates of ion exchange and electron transfer.\u003c/p\u003e \u003cp\u003eEffective material interaction at the electrochemical interface is crucial for applications in energy storage and catalysis, making these properties fundamental. Additionally, the detection of some spheres exhibiting uniform surface architecture, while others display non-uniformity across all spheres, indicates that the synthesis process of the rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite necessitates further refinement of the processing parameters. Following further annealing of the sample, there is a little propensity for the spheres to cluster together on their surfaces (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ef). Uniformity in surface structure is indicative of a fully developed composite, essential for ensuring the material\u0026rsquo;s performance and functional properties in various applications.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eEDS was also used to quantify the samples' elemental composition. Focusing on and covering different sections of the samples, the EDS measurements were carefully carried out to guarantee complete and accurate results. This method produced a representative elemental analysis and assisted in mitigating any local compositional differences. The obtained spectra are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and show different peaks according to the components present. A table that summarizes the atomic percentages of carbon (C), oxygen (O), and cobalt (Co) for every sample is also included, making it easier to compare the elemental makeup of the various samples in detail.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e3.4 XPS studies\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eXPS investigations were carried out to look into the elemental composition and chemical states of annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite. The carbon component in the sample is displayed in the C1s spectrum in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ea. The O1s spectrum, which is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eb, is a crucial tool for understanding the compound's oxygen environment. The Co 2P spectrum, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ec, offers important information on the Co states that are present in the material. The spectrum clearly shows two distinct peaks that correspond to the Co 2p\u003csub\u003e3/2\u003c/sub\u003e and Co 2p\u003csub\u003e1/2\u003c/sub\u003e orbital levels, with binding energies of 780 eV and 796.5 eV, respectively [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The physical evidence provided by the observed peaks supports the presence of a spinel structure and thus the +\u0026thinsp;2 and +\u0026thinsp;3 oxidation states of cobalt. In addition to supporting the identification of the spinel phase of Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e, the current analysis indicates the termination of the spinel surface, indicating a specific orientation consistent with the stabilization of Co\u003csup\u003e2+\u003c/sup\u003e and Co\u003csup\u003e3+\u003c/sup\u003e species at the surface.\u003c/p\u003e \u003cp\u003eThermal gravimetric analysis (TGA) is a technique that quantifies the changes in a material\u0026rsquo;s physical and chemical properties either over time at a constant temperature and/or mass loss, or as temperature increases at a constant heating rate. Their TGA further validated the rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanocomposite's percentage composition and thermal stability. The thermogravimetric profiles of the pristine and heat-treated samples are displayed in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e. The sample as prepared shows a 4% weight drop, which is explained by the removal of physically adsorbed water content [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBy contrast, an extra 20% of weight is lost in the annealed sample. The plot indicates that the initial stage of decomposition was observed up to 200\u0026deg;C, which is most likely connected to the evaporation of leftover H\u003csub\u003e2\u003c/sub\u003eO (about 5%). The second weight loss occurred between 200 and 600 degrees Celsius, a temperature range linked to chemical processes such dehydration, deterioration, and condensation as well as the heat-induced breakdown of materials. This stage is characterized by a loss of aliphatic character that simultaneously releases gas and increases aromaticity. A significant weight loss is seen above 700\u0026deg;C, indicating that the material has undergone significant breakdown.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.5 BET and BJH studies\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e shows the BET surface area analysis of the annealed sample revealed a surface area of 1.0612 m\u0026sup2;/g. This relatively high surface area contributes to the enhanced electrochemical performance of the material. Furthermore, the BJH analysis indicated a pore diameter of 1.76 nm and a pore volume of 0.00025 cm\u0026sup3;/g for the annealed sample. These structural properties suggest that the material is well-suited for applications requiring efficient energy storage and improved electrochemical behavior.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.6 Electrochemical studies\u003c/h2\u003e \u003cp\u003eUsing a variety of electroanalytical techniques, the electrochemical characteristics of the as-prepared and annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite are investigated. The three main analytical techniques used in these studies are EIS, CP, and CV in a three-electrode glass cell setup (the electrodes are presented in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The purpose of this work is to determine how the annealing procedure affects the rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite electrochemical performance.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eList of electrodes\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS.No.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eName of the electrode\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMaterial used\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWorking electrode\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAnnealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReference electrode\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAg/AgCl\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCounter electrode\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePlatinum foil\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eElectrolyte\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1M KOH\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eCV provides insights into the redox properties of nanomaterials by monitoring the current resulting from electrochemical reactions as a function of applied voltage. This method indicates possible modifications in the electronic structure after annealing and aids in comprehending the oxidative and reductive properties of the nanoparticles. The CV micrographs of the annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite in various potential windows are displayed in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ea at scan rate of 10 mV/s. The sample is seen to exhibit larger area between \u0026minus;\u0026thinsp;0.1 and 1.0 V. As a result, further CV research is done in the window at various scan rates, as seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003eb. It can be seen from Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003eb that when scan rate increases, the loop size of the CV curve decreases which indicate the lower in specific capacitance with increase in scan rate [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. To calculate specific capacitance, the formula typically used is [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] :\u003c/p\u003e \u003cp\u003e \u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e\\(\\:\\text{C}=\\:\\frac{\\int\\:\\:\\text{I}\\:\\left(\\text{V}\\right)\\text{d}\\text{V}}{2\\text{m}(\\text{V}2\\:-\\:\\text{V}1){\\Delta\\:}\\text{V}}\\)\u003c/span\u003e \u003c/span\u003e (F/g) ------(1)\u003c/p\u003e \u003cp\u003eHere,\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSymbol\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParameter\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eUnit\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003especific capacitance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFarad gram\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eI (V)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003einstantaneous current\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eampere\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026int;I (V) dV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003etotal voltametric charge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ecoulomb\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003em\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003emass of active material (5.59 x 10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003egram\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003escan rate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003evolt second\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eV2-V1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003epotential window\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003evolt\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe annealed sample showed the specific capacitance values of 602, 567, 501, 434, 387, 311, 267, 210, 176 F/g at a scan rate of 1, 2, 5, 10, 20, 50, 100, 200 and 300 mV/s in a 1M KOH aqueous solution respectively, according to the equation above. The measure values are greater than those already reported for rGO-Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e nanocomposite which was carried out in 1M H\u003csub\u003e2\u003c/sub\u003eSO\u003csub\u003e4\u003c/sub\u003e which indicates the aqueous alkaline electrolytes are better for TMO composites [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e] The charge-discharge rates of the nanocomposites can be examined using a technique called chromatopotentiometry (CP), in which the current is maintained constant while the potential changes are monitored. Because annealing can cause structural changes, this approach is especially helpful for assessing the kinetic aspects of the electrode processes.\u003c/p\u003e \u003cp\u003eThe annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite charge discharge curves employing the galvanostatic charge-discharge (GCD) technique are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ec at different current densities of 1, 2, 3 and 5 A/g. The charge-discharge curves are extremely symmetrical which suggests electrochemical reversibility of the nanocomposite [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. The specific capacitance values of the sample was calculated from charge-discharge curves using the following formula and [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] and are presented in the following Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e\\(\\:C=\\:\\frac{I\\:\\varDelta\\:t}{m\\varDelta\\:V}\\)\u003c/span\u003e \u003c/span\u003e (F/g) ------(2)\u003c/p\u003e \u003cp\u003eHere,\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSymbol\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParameter\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eUnit\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003especific capacitance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003efarad gram\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003egalvanostatic discharge current\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eampere\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003edischarge time\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003esecond\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003em\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003emass of active material (5.59 x 10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003egram\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eΔV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003evoltage range\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003evolt\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabb\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSpecific capacitance of the samples at different current densities\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCurrent Density (A/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSpecific Capacitance (F/g)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eAnnealed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1056\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e896\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e678\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e456\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe annealed sample's cyclic consistency is examined and shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ed. The sample's capacitive retention at a current density of 5 A/g after 5000 consecutive cycles is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ed. After 5000 cycles, the annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite maintained 75% capacitance, suggesting a long cycle life. SEM images showed that the sample's unique morphology and low aggregation states may have contributed to its greatest capacitive retention. This suggests that due of the strong particle interactions, the active material is also integrated during the cycles. The Nickel foam, XRD spectrum and SEM micrographs are shown in the inset of Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ed. Figure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ee showed the first 50 cycles of charge-discharge to understand the polarization of the polarization charge during the cycling. In addition, Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ef showed the first and last 5 charge-discharge cycles to understand the symmetry of the cycles and columbic efficiency of the sample. It is observed 100% columbic efficiency after 1000 cycles. The obtained results were compared with the already reported work as given in the Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e. It is to be noted that the sample\u0026rsquo;s leakage current values were found to be less than 5 \u0026micro;A, indicating high quality and stability and exhibited a self-discharge time of approximately 24 hours, with only a 18% drop in voltage during this period.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResults comparison\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS.No.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMaterial\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMethod of Preparation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSpecific Capacitance (F/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCapacitive retention (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCycles\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCo\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e/rGO/CNTs nanocomposite\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ehydrothermal method\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e790 F g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u0026nbsp;at 1 A g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eP-Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e/RGO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePhosphating treatment\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e448 F g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e at 1 A g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRGO-Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e-PPy composite films\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ehydrothermal method\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e532.8 F g -1 at 0.2 A g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e700\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCo\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e/rGO nanocomposites\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ehydrothermal method\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e754 Fg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCo\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e/reduced graphene oxide (rGO) composite\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ehydrothermal method\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e916.6\u0026nbsp;F\u0026nbsp;g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u0026nbsp;at 0.5\u0026nbsp;A\u0026nbsp;g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e\u0026nbsp;Composites\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ecoprecipitation method\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e546\u0026nbsp;F\u0026nbsp;g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e at 1\u0026nbsp;A\u0026nbsp;g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCo\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e/r-GO nanocomposite\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ehydrothermal routes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e865 Fg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u0026nbsp;@ 1 Ag\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e93.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003erGO/Co\u003c/b\u003e\u003csub\u003e\u003cb\u003e3\u003c/b\u003e\u003c/sub\u003e\u003cb\u003eO\u003c/b\u003e\u003csub\u003e\u003cb\u003e4\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e@Ni nanocomposite\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eHydrothermal method\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1056 Fg\u003c/b\u003e\u003csup\u003e\u003cb\u003e\u0026minus;\u0026thinsp;1\u003c/b\u003e\u003c/sup\u003e\u0026nbsp;\u003cb\u003eat 1\u003c/b\u003e A g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e75\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e5000\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003ePresent work\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe Nyquist plot was obtained for annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite using electrochemical impedance spectroscopy (EIS) in the frequency range of 1 Hz to 1 MHz shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003eg\u0026amp;h. The Nyquist plot indicates the semicircle in the high-frequency region while the straight line is in the low-frequency region. The Nyquist plot intercepting at x intercept gives the internal resistance (Rs) of 1.3 Ω. While the diameter of semicircles gives the charge transfer resistance (Rct) which was 2.2 Ω.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.7 Magnetic studies\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e illustrates the temperature dependence of magnetization under zero-field cooled (ZFC) and field-cooled (FC) conditions. A subtle peak around 50 K characterizes the ZFC curve, and significant divergence between the ZFC and FC curves emerges at lower temperatures. Specifically, at 5 K, the magnetization in the FC scenario is nearly twice that observed in the ZFC condition. For temperatures above 60 K, the magnetization curve becomes linear, aligning with the Curie-Weiss law. The estimated effective magnetic moment per ion in the paramagnetic phase is approximately 4.35 \u0026micro;B, which is in agreement with previous findings.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003e subsequently details the magnetic properties of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite at temperatures of 5 K and 300 K. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003e, the hysteresis curve of as-prepared rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite exhibits ferromagnetic behavior at all temperatures spanning from 5 K to 100 K, although the saturation magnetization was found to drop from 0.913 to 0.621 emu/g. The sample's ferromagnetic behavior can be related to uncompensated surface spins and limited size effects [\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMaterials possessing both supercapacitive and magnetic properties present significant utility in the realm of advanced technological applications, due to their dual functionality which enables innovative solutions across diverse sectors such as electronics, energy storage systems, and biomedical engineering. The integration of supercapacitive behavior facilitates rapid charge and discharge cycles, high power density, and efficient energy storage capabilities. Concurrently, the intrinsic magnetic properties of these materials allow for manipulation and control using external magnetic fields, enhancing their applicability in magnetic sensors, actuators, and targeted delivery systems in medical applications.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThe rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite was synthesized using a straightforward hydrothermal method at 200\u0026deg;C, followed by vacuum annealing at 600\u0026deg;C to optimize its properties for supercapacitor applications. Characterization through XRD and Raman spectroscopy confirmed the cubic crystal structure of the nanocomposite, while SEM analyses demonstrated that the morphology was consistently influenced by the annealing temperature. Notably, the annealed samples exhibited a complete formation of the nanocomposite structure. Electrochemical testing revealed that the annealed rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposite electrodes achieved a peak specific capacitance of 1056 F/g at a current density of 1 A/g using an aqueous 1M KOH electrolyte. Furthermore, after 5000 charge-discharge cycles at 5 A/g, the electrodes retained 75% of their initial capacitance, indicating robust electrochemical stability. This study underscores the necessity of optimizing the annealing process to enhance the surface area and morphological features of the nanocomposites, which are crucial for maximizing their electrochemical performance. Notably, they maintained a significant proportion of their initial capacitance after 5000 cycles, underscoring their potential for high-performance energy storage applications. Additionally, the magnetic properties of the nanocomposites suggest potential applications in magnetic memory devices, benefitting from their exhibited ferromagnetic behaviour.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e-Authors Contributions\u003c/p\u003e\n\u003cp\u003eDr. Dadamiah PMD Shaik: Writing \u0026ndash; review \u0026amp; editing, Writing \u0026ndash; original draft, Methodology, Funding acquisition, Formal analysis, Data curation. Rosaiah Pitcheri: Writing \u0026ndash; review \u0026amp; editing, Writing \u0026ndash; original draft, Methodology, Formal analysis, Data curation. Ayman A. Ghfar: Writing \u0026ndash; review \u0026amp; editing, Formal analysis, Data curation, Conceptualization-Funding, Naresh Kumar Reddy P: Writing \u0026ndash; review \u0026amp; editing, Formal Analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e-Competing Interests- Not applicable\u003c/p\u003e\n\u003cp\u003e-Funding: This work is funded by King Saud University, Saudi Arabia\u003c/p\u003e\n\u003cp\u003e-Data availability: Data will be available on request\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEthics, Consent to Participate, and Consent to Publish declarations: not applicable.\u003c/p\u003e\n\u003cp\u003eclinical trial declarations: not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors are greatful to the Researchers Supporting Project number (RSP2025R407), King Saud University, Riyadh, Saudi Arabia for the financial support.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eRosaiah, P., Yue, D., Dayanidhi, K., Ramachandran, K., Vadivel, P., Sheik Eusuff, N., Minnam Reddy, V.R., Kim, W.K. 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High electrochemical performance of spinel Mn₃O₄ over Co₃O₄ nanocrystals. \u003cem\u003eJ. Mol. Struct.\u003c/em\u003e \u003cstrong\u003e1241\u003c/strong\u003e, 130619 (2021). https://doi.org/10.1016/j.molstruc.2020.130619\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-sustainability","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"disu","sideBox":"Learn more about [Discover Sustainability](https://www.springer.com/43621)","snPcode":"","submissionUrl":"","title":"Discover Sustainability","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Energy Storage, Supercapacitors, Hydrothermal method, Electrochemistry, Magnetic properties","lastPublishedDoi":"10.21203/rs.3.rs-5852230/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5852230/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis work involved the hydrothermal synthesis of rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni nanocomposites at low temperatures, followed by annealing at 600\u0026deg;C. The microstructural and electrochemical characteristics of the nanostructured rGO/Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@Ni were evaluated in detail. A Co\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e cubic structure with the space group Fd̅3m(227) and distinct peaks at the (220), (311), (222), (400), (422), (511), and (440) planes was formed, according to XRD analysis. Raman measurements confirmed the presence of Co-O bonds and provided detailed information on the microstructure of the samples. SEM analysis of the shape and surface architecture demonstrated the unique properties of the porous nanoparticles. The existence of Co\u003csup\u003e2+\u003c/sup\u003e and Co\u003csup\u003e3+\u003c/sup\u003e ions was verified by XPS. The nanocomposites demonstrated improved electrochemical stability and a peak capacitance of 1056 F/g at a current density of 1 A/g in electrochemical tests carried out in an aqueous 1M KOH electrolyte.\u003c/p\u003e","manuscriptTitle":"Development and Comprehensive Analysis of rGO/Co3O4@Ni nanocomposite: Dual-Functional Materials for Magnetic and Supercapacitor Applications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-29 07:26:37","doi":"10.21203/rs.3.rs-5852230/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-28T14:54:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-22T12:13:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-15T01:26:50+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"110578571986377588850021859360718052338","date":"2025-04-15T01:13:41+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-14T20:58:56+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"5805874225267766989998677074105715487","date":"2025-04-14T16:24:49+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-14T15:31:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-10T05:13:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Sustainability","date":"2025-03-14T07:13:23+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-sustainability","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"disu","sideBox":"Learn more about [Discover Sustainability](https://www.springer.com/43621)","snPcode":"","submissionUrl":"","title":"Discover Sustainability","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cff350de-2079-44cf-895c-5c4e6dbf3e7d","owner":[],"postedDate":"April 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-12-10T22:23:15+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-29 07:26:37","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5852230","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5852230","identity":"rs-5852230","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}