Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure

Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure Qianqian Su, Yachong Liu, Xi Zou, Xinle Tian, Ruizhe Xiao, Yan Su, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6624432/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Interfacial strain engineering, achieved through the precise control of lattice mismatch, holds implications for both fundamental and technological applications. However, unravelling the correlation between interfacial lattice strain and material properties at the nanoscale remains challenging due to limitation in regulating both the type and magnitude of strain at the nanoscale. Here, we observe long-distance ion migration induced by interfacial lattice strain in a series of lanthanide core-shell nanofluorides. By deliberately manipulating interfacial strain using lanthanide cations with varying ionic radii, the lattice mismatch promotes lanthanide migration across heterostructure interfaces and thus influences crystal growth dynamics and subsequent optical features. Notably, when lattice mismatch exceeds 5.1%, lanthanide ions within core nanoparticles can diffuse up to 13 nm along the [1000] crystallographic direction, crossing the interface and migrating into the shell layer of hexagonal-phase NaLnF 4 core-shell-shell nanolattices. Mechanistic investigation indicates that large interfacial tensile strain and slow shell growth are beneficial for strain relaxation via ion diffusion. These findings provide new insights into strain-driven ion diffusion at the nanoscale and open avenues for novel heterogeneous nanocrystals development with precisely tailored structures and confined active ions. These advancements could promote a range of applications, including bioimaging, nanocatalysis, quantum information, and many others. Physical sciences/Nanoscience and technology/Nanoscale materials/Nanoparticles Physical sciences/Optics and photonics/Optical materials and structures/Nanoparticles Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Strain engineering has emerged as a crucial strategy for directing heteroepitaxial growth and modulating the optical, electrical, catalytic, and magnetic functionalities of advanced nanomaterials 1 – 7 . However, interfacial strain is often thermodynamically unstable and may be partially alleviated through ion diffusion, defect formation, or phase transition, which drive the system from a metastable state to a more stable configuration 8 – 10 . Even after partial relaxation, residual strain can substantially impact the structural integrity of the epitaxial shell, which in turn affects the overall properties of the resulting nanocrystals. In particular, previous studies have highlighted that cation inter-diffusion at interfaces or grain boundaries—driven by surface energy minimization, defect density gradients, or dopant redistribution—can significantly influence the emission efficiency, catalytic activity, and magnetic coercivity of heterostructured nanocrystals 11 – 16 . These findings indicate that precisely regulated interfacial ion migration can serve as a powerful tool to tailor nanocrystal functionalities, offering exciting prospects for next-generation technologies in optoelectronics 17 , 18 , energy conversion 19 , 20 , quantum technologies 21 , 22 , and biomedical engineering 23 – 25 . However, limited attention has been directed toward understanding how strain affects the interface integrity of core-shell nanoparticles 26 , leaving the relationship between interfacial strain and cation diffusion dynamics poorly understood 27 . Therefore, controlling cation migration through interfacial strain engineering is essential for unlocking the full potential of core-shell nanoparticles, enabling the development of nanomaterials with tailored properties and driving innovations across diverse applications in nanotechnology. Here, we choose lanthanide-doped fluoride heterostructured nanocrystals as model systems and present direct evidence of lanthanide migration across interfaces in multilayered nanocrystals, specifically NaErF 4 @NaYF 4 @NaLnF 4 (Ln = Lu, Y, Tb, Gd, Eu, Nd, Pr, and Ce). Mechanistic investigation reveals that lattice mismatch between different layers plays a pivotal role in regulating the diffusion dynamics of the lanthanide dopants. Notably, tensile strain exerted by shell layers containing large-size lanthanides facilitates lanthanide migration from the core to the surface or near-surface area, with diffusion lengths exceeding 10 nm. Moreover, we demonstrate that lanthanide diffusion can be regulated through interfacial strain engineering by controlling the type of nanocrystal precursors and the deposition rates during shell growth. This regulation enables precise control over lanthanide distribution and ultimately the optical performance of the nanostructures. Results Theoretical basis of lanthanide migration. In given heterostructures, lattice mismatch often induces misfit strain at interfaces, with larger mismatches typically leading to greater strain 28 . To theoretically study the impact of interfacial misfit strain on crystal structure at the atomic level, we selected a hexagonal-phase NaErF 4 @NaNdF 4 core-shell crystal characterized by a large lattice mismatch and low lattice symmetries (Supplementary Fig. 1). Upon lattice optimization, the calculated lattice mismatch between the NaErF 4 (0001) facet and the NaNdF 4 (0001) facet is approximately 2.74%, considerably smaller than that calculated for the (1000) facet (~ 6.15%, Fig. 1 a). Note that these two facets were chosen for their low surface energies 29 . We calculated the adsorption energies of a Nd atom on the (0001) and (1000) facets of the NaErF 4 by first-principles calculations based on density functional theory (DFT). For the (0001) facet, only minor changes in the adsorption energies were observed between the strain-free and moderately stretched surfaces. In contrast, the adsorption energies on the stretched (1000) facet increased significantly compared to the strain-free condition. Specifically, for the (1000) facet, Nd atoms preferentially adsorbed on the top of the surface Er atoms, exhibiting a high adsorption energy of -4.16 eV without external strain (Supplementary Table 1). Notably, this energy increased by 46% under applied tensile strain of 6.15%. This energetic change suggests that misfit strain at different interfaces alters the local electronic environment and atomic arrangement, thereby impacting the binding strength between the adsorbate and substrate (Supplementary Figs. 2–4). Furthermore, the strain-strengthened binding indicates that lattice misfit elevates the energy of the (1000) facet. This increase in energy likely facilitates the dissolution of the (1000) facet, thereby promoting the growth of the thermodynamically more stable (0001) facet through intraparticle diffusion processes 30 . By employing different lanthanide ions (Lu, Er, Y, Tb, Gd, Eu, Nd, Pr, and Ce), it is feasible to modulate the misfit strain at distinct interfaces within a single core-shell nanocrystal (Supplementary Tables 2–5). In this regard, we hypotheses that lanthanides adsorbed on the metastable interface with substantial misfit strain have high likelihood to migrate toward the (0001) facet or the core area to release interfacial strain (Fig. 1 b). Lanthanide migration of NaErF 4 @NaYF 4 @NaNdF 4 . To validate our hypothesis, we designed a NaErF 4 @NaYF 4 @NaNdF 4 core-shell-shell nanostructure (Fig. 2 a). Given the similar lattice constant of NaErF 4 and NaYF 4 crystals, NaErF 4 @NaYF 4 core-shell nanoparticles were first chosen for their negligible interfacial stain of ~ 0.5%. As anticipated, a NaYF 4 shell exhibited a seamless coating on the NaErF 4 nanocrystals (Supplementary Fig. 5). Moreover, energy dispersive X-ray (EDX) elemental mapping analysis indicated an even distribution of Er 3+ and Y 3+ ions in the core and shell regions, respectively (Fig. 2 b). We next coated a NaNdF 4 shell on the NaErF 4 @NaYF 4 core-shell nanoparticles, by hot injection at a low injection rate of approximately 6.7 µmol/min, corresponding to an injection time of 60 min, to study the lanthanide diffusion driven by a large lattice mismatch between NaYF 4 and NaNdF 4 layers. TEM images revealed that the resulting NaErF 4 @NaYF 4 @NaNdF 4 multilayered nanoparticles crystallized in a rod-like structure (Fig. 2 c). We also collected samples at intervals of 1, 5, 10, 20, 30, and 60 minutes to examine morphological changes during shell growth. TEM images showed that NaErF 4 @NaYF 4 @NaNdF 4 nanoparticles evolved from quasi-sphere to quasi-rhombuses and then to rod-like nanocrystals (Supplementary Fig. 6). Notably, elemental mapping analysis revealed that Nd 3+ ions were mainly located at the opposite ends of the NaErF 4 @NaYF 4 nanoparticles, indicating preferential precursor deposition and growth on the largely exposed, high-energy (1000) surface of the seed nanoparticles 31 , 32 . Notably, we found that Y 3+ ions were not evenly wrapped around the Er cores, but diffused to the two ends of the nanorods, and distributed uniformly in the Nd shell (Fig. 2 c, d). Apart from the intermixing between Y 3+ and Nd 3+ ions in the shell layers, elemental mapping also showed a substantial amount of Er 3+ ions diffusing across the interfaces to the Nd layer (Fig. 2 c). A long-distance migration of approximately 13 nm along the [0001] direction was estimated in the hetero-nanostructures under study. To further evaluate the interface strain-induced diffusion length, we synthesized a series of NaErF 4 @NaYF 4 @NaNdF 4 nanocrystals with different NaYF 4 -spacer thicknesses. Surprisingly, we found that the core Er 3+ could diffuse to the Nd shell even when the thickness of the Y spacer was up to 6.8 nm (Fig. 2 e). Considering that the misfit strain originates from the Nd-Y interface, the diffusion of lanthanides from the core area to the outer shell suggested a long-range nature of strain relaxation dynamics. The intermixing of Nd 3+ , Y 3+ , and Er 3+ ions significantly shortened the distance between the Nd 3+ and Er 3+ ions, which could trigger strong resonant energy transfer from the Er 3+ to Nd 3+ ions upon light excitation 33 , 34 . By directly pumping the Er 3+ emitters, the spectroscopy measurements showed markedly quenched photoluminescence and shortened lifetime of Er 3+ in the NaErF 4 @NaYF 4 @NaNdF 4 nanoparticles compared with that observed in the NaErF 4 @NaYF 4 nanoparticles, again confirming the close proximity of Nd 3+ to Er 3+ ions (Fig. 2 f, g, and Supplementary Fig. 7). We next investigated the mechanism behind long-range cation migration in multilayered nanocrystals. It should be noted that lattice vacancies create empty sites within the crystal structure, which can serve as pathways for ions to move (Fig. 2 h, left diagram). In this regard, the rate of substitutional diffusion is influenced by two primary factors: the ease of vacancy formation and the mobility of atoms into those vacancies 35 , 36 . Interfacial misfit strain at interfaces in the NaErF 4 @NaYF 4 @NaNdF 4 core-shell system is expected to promote lanthanide diffusion as the substantial lattice mismatch between NaYF 4 and NaNdF 4 introduces structural distortions that facilitate vacancy creation (Fig. 2 h, right diagram). We then modulated cation diffusion through interfacial strain engineering by adjusting the Nd precursor injection rate, thereby influencing the diffusion dynamics and growth behavior at the core-shell interface (Supplementary Fig. 8). X-ray diffraction (XRD) patterns confirmed that all samples maintained a pure hexagonal crystal structure (Supplementary Fig. 9). The diffraction peaks of the core-multishell structures shifted to lower diffraction angles relative to the core pattern, demonstrating the incoherent epitaxial growth with compressively strained shell 37 . In addition, the asymmetrical broadening of these diffraction peaks indicates an uneven distribution of lattice spacings due to the formation of lattice defects or distortion in the heterostructured crystal. TEM images revealed patch-like Nd shell fragments on the NaErF 4 @NaYF 4 nanocrystals at an injection rate of 80.0 µmol/min over 5 minutes (Fig. 3 a-d and Supplementary Fig. 10). As the injection rate decreased, the nanoparticle morphology evolved from star-like (80.0, 40.0, 20.0 µmol/min) to a triangular (13.3 µmol/min) and finally to rod-like shape (6.7 µmol/min). The crystal structure and lattice mismatch in nanocrystals is effectively visualized through high-resolution TEM (HRTEM) characterization 24 . HRTEM also showed that NaErF 4 @NaYF 4 nanocrystals initially exhibited a single crystal structure (Supplementary Fig. 11). Upon introducing Nd 3+ ions, significant structural changes were observed. At high injection rates, the nanocrystals displayed a polycrystalline structure (Fig. 3 e, f, and Supplementary Figs. 12–14) and transformed to a single crystal-like structure at slow injection rates (Fig. 3 g, h). We also examined the interfacial regions using HRTEM and inverse fast Fourier transform (IFFT) analysis and found discontinuities in lattice fringes of regions e and f, indicative of lattice mismatch and strain, while lattice fringes became more orderly at lower injection rates (Fig. 3 E-H and Supplementary Fig. 15). These results indicate that variations in the injection rate affect growth dynamics and precursor deposition, which is consistent with the previous study 38 . Elemental mapping of these nanoparticles revealed that the NaErF 4 @NaYF 4 core maintains a nearly spherical shape (Fig. 2 a). Following the rapid injection of the Nd precursor, the Er core retains its shape, while the distribution of Y 3+ ions of the interlayer begins to resemble that of the outer Nd shell (Fig. 3 i, j, and Supplementary Fig. 16). In contrast, at low injection rates, the shape of Er core increasingly mimics that of the Nd shell, and the distribution of interlayer Y 3+ ions tends to overlap with Nd shell (Fig. 3 k, l, and Supplementary Fig. 16). High injection rates can lead to uneven precursor distribution and confined growth, limiting cation diffusion and preventing effective diffusion to stable sites. In contrast, low injection rates facilitate uniform distribution of precursors, allowing pre-deposited ions to diffuse toward stable sites sufficiently before the arrival of the next batch of precursors. Thus, the interplay between injection rate, growth kinetics, and surface energy critically determines the morphological changes of the nanocrystals and diffusion of cations. These findings also suggest that misfit strain relaxation through ion diffusion is favored, likely due to increased defects facilitating ion movement and lowered migration energy barriers at slow injection rates. For spectroscopy measurements, we found that the luminescence from Er 3+ emitters was markedly attenuated as the injection rates decreased (Supplementary Fig. 17). For instance, nanoparticles synthesized at an injection rate of 40.0 µmol/min exhibited approximately 29-fold and 100-fold higher luminescence at 500–700 nm and 1400–1600 nm, respectively, compared with that recorded in the nanoparticle prepared at an injection rate of 6.7 µmol/min (Supplementary Fig. 18). Note that the corresponding luminescence lifetime gradually decreased as the injection rate decreased. These findings corroborated enhanced energy transfer from the Er 3+ ions to their neighboring Nd 3+ ions and strong lanthanide intermixing in nanoparticles. Universality of lanthanide migration. By taking advantage of lanthanide contraction, we systematically studied the effects of interfacial strain and epitaxial growth kinetics on lanthanide diffusion. Specifically, the NaErF 4 @NaYF 4 nanoparticles were coated with Lu, Y, Tb, Gd, Eu, Pr and Ce shells, generating misfit strains of -2.0%, 0%, 1.4%, 2.0%, 2.4%, 6.0%, and 7.0%, respectively. TEM images revealed that minor misfit strain on the NaErF 4 @NaYF 4 surface promoted a coherent epitaxial growth, while higher misfit strain levels induced non-coherent growth (Fig. 4 a), which is also consistent with the previous report 24 , 38 . In the case of NaErF 4 @NaYF 4 @NaYF 4 nanoparticles, the outmost Y shell, which applied zero strain, maintained a single-crystal structure, with minimal Er 3+ ion migration (Fig. 4 b, and injection rate: 6.7 µmol/min). In contrast, when applying compressive strain on the Er core through the coating of Lu shell, we observed that the strain barely affected the diffusion of Er 3+ but did promote Y 3+ diffusion, as evidenced by the similarity of its distribution to that of the outer Nd shell under slow growth conditions (Fig. 4 c). Interestingly, the Tb shell, with a misfit strain of 1.4%, triggered a significant long-range Er 3+ migration under slow growth rates (Fig. 4 d, and injection rate: 6.7 µmol/min), suggesting that tensile strain plays a primary role in governing diffusion dynamics. For the Eu shell, which applied moderate strain, we observed that the distribution of Er 3+ closely aligned with the outer Nd shell, even at a modest growth rate of 6.7 µmol/min (Fig. 4 e). In the case of Pr and Ce shells, the large lattice mismatches at Y-Pr and Y-Ce interfaces hindered the uniform formation of nanoparticle. Nevertheless, these samples exhibited rod-like morphologies and intense Y 3+ diffusion, though Er 3+ diffusion was limited by relatively higher growth rates (Fig. 4 f, 20.0 µmol/min, and Supplementary Fig. 19). Taken together, significant lanthanide diffusion was detected with Tb, Eu, Gd, Nd, Pr and Ce coatings, while Y-coated nanoparticles exhibited almost no diffusion (Fig. 4 and Supplementary Figs. 19–21). Slow epitaxial growth facilitated lanthanide diffusion, whereas compressive strain and rapid shell growth could suppress lanthanide diffusion to some extent. The photoluminescence and lifetimes of the nanocrystals correlated with the distribution of the lanthanide ions (Supplementary Figs. 22–25). High lattice mismatches introduced substantial strain, creating vacancies and defects that facilitate ion diffusion by lowering energy barriers and increasing defect density. Consequently, larger mismatches create a thermodynamically favorable environment for ion diffusion, allowing ions to migrate to energetically favorable sites and alleviate local strain. In contrast, smaller mismatches, such as those involving Y, may not promote significant diffusion due to zero mismatch strain, resulting in more stable configurations with limited ion movement. Discussion In summary, we systematically investigated the effect of lattice mismatch-induced interfacial strain on heterogeneous epitaxial growth and ion diffusion within nanolattices. Using hexagonal-phase core-shell NaErF 4 @NaYF 4 @NaLnF 4 (Ln = Lu, Y, Tb, Gd, Eu, Nd, Pr and Ce) nanocrystals as model systems, we demonstrated that lanthanide diffusion across interfaces can be effectively controlled through misfit strain engineering, involving adjustments of shell growth dynamics and the magnitude of misfit strain (-2.0–7.0%). Specifically, in NaErF 4 @NaYF 4 @NaNdF 4 nanocrystals with a substantial misfit strain of 5.1%, we observed that Er 3+ ions in the core and Y 3+ ions in the spacer migrated over 10 nm to the outer Nd shell, mainly along the (0001) crystallographic direction. These findings not only enhance our understanding of interfacial strain relaxation dynamics but also enable precise control over ion diffusion in heterostructure nanolattices, advancing the development of strain-engineered nanocrystals with intriguing electronic, optical, magnetic, or catalytic properties. Materials and Methods Materials. Y(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Nd(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Gd(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Tb(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), LuCl 3 ·xH 2 O (99.9%), Er(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Ce(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Eu(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), Pr(CH 3 CO 2 ) 3 ·xH 2 O (99.9%), NaOH (> 98%), NH 4 F (> 98%), oleic acid (OA, 90%), 1-octadecene (ODE, 90%), sodium oleate and sodium trifluoroacetate (Na-TFA) were all purchased from Sigma-Aldrich. Hydrochloric acid (AR), absolute methanol (AR), cyclohexane (AR) and ethanol (AR) were obtained from Sinopharm Chemical Reagent Co., Ltd. All chemicals were used as received without further purification. Synthesis of NaErF 4 core nanocrystals. NaErF 4 core nanocrystals were prepared by a modified literature procedure 39 . A total of 4 mL of rare-earth acetate Er(CH 3 CO 2 ) 3 (0.275 g, 0.80 mmol) aqueous solution, oleic acid (10 mL), and octadecene (10 mL) were added to a 50 mL three-neck flask, and the mixture was stirred and heated to 150 o C (750 rpm/min) for 1.5 h, and then cooled down to room temperature naturally. Next, the flask was transferred to the heating mantle, and then sodium oleate (0.761 g, 2.50 mmol) was added. The reaction was maintained at 100 o C under vacuum condition for 1 h. Subsequently, NH 4 F powder (0.148 g, 4.00 mmol) was added to the three-neck flask under nitrogen, and then slowly heated to 160 o C for 1.5 h. After vacuumizing for 10 min, the reaction was heated to 320 o C and kept at this temperature under nitrogen protection for 0.5 h before cooling down to room temperature. The resulting mixture was centrifugated and washed three times (8000 rpm, 5 min) using ethanol/cyclohexane (v/v = 3/2), and finally dispersed in 8 mL cyclohexane prior to being used for shell coating. The synthesis of NaNdF 4 and NaErF 4 :50%Nd was identical to that for NaErF 4 nanoparticles except for using the different compositions of dopants. Synthesis of NaErF 4 @NaYF 4 core-shell nanocrystals. The core-shell nanocrystals were synthesized by a modified method 39 , 40 . The obtained NaErF 4 core nanocrystals were used as seeds for the shell coating. A 2 mL aqueous solution of Y(CH 3 CO 2 ) 3 (0.106 g, 0.40 mmol), oleic acid (4 mL) and octadecene (6 mL) were added to a 50 mL three-neck flask. The temperature was heated to 150 o C and maintained at this temperature for 1.5 h (750 rpm/min) before cooling down to 50 o C. Then, 4.4 mL methanol solution of NH 4 F (0.050 g, 1.36 mmol) and NaOH (0.040 g, 1.00 mmol) was quickly added and kept for 0.5 h, and then slowly heated to 80 o C for 0.5 h to remove methanol. At the same time, NaErF 4 (4 mL) dispersed in cyclohexane was added into a 50 mL three-neck flask, then oleic acid (4 mL) and octadecene (6 mL) were added and heated to 80 o C to remove cyclohexane. Then, the temperature was slowly increased to 100 o C for 30 min in vacuo . After the end, the temperature was heated at a constant rate to 310 o C in a nitrogen environment. The treated shell precursor was injected at a uniform rate for 40.0 µmol/min (10 min), and then the reaction was cooled down to room temperature. The sample was centrifugally washed three times (8000 rpm, 5 min) using ethanol/cyclohexane (v/v = 3/2), and finally dispersed in 4 mL cyclohexane. Synthesis of NaErF 4 @NaYF 4 @NaNdF 4 core-multishell nanocrystals. The preparation of the above-mentioned and other core-multishell nanocrystals, including NaErF 4 @NaNdF 4 (Er@Nd) NaErF 4 @NaYF 4 @NaNdF 4 (Er@Y@Nd), NaErF 4 @NaYF 4 @NaTbF 4 (Er@Y@Tb), NaErF 4 @NaYF 4 @NaYF 4 (Er@Y@Y), NaErF 4 @NaYF 4 @NaGdF 4 (Er@Y@Gd), NaErF 4 @NaYF 4 @NaLuF 4 (Er@Y@Lu), NaErF 4 @NaYF 4 @NaCeF 4 (Er@Y@Ce), NaErF 4 @NaYF 4 @NaPrF 4 (Er@Y@Pr), NaErF 4 @NaYF 4 @NaEuF 4 (Er@Y@Eu), were the same as that for core-shell nanocrystals except for the use of a shell with different lanthanide ions and shell injection rates. The preparation of NaErF 4 @NaYF 4 @NaNdF 4 (6.7 µmol/min, sampling time: 1 min − 60 min) core-multishell nanocrystals were the same as that for core-shell nanocrystals except for 0.5 mL of stock solution was taken at fixed time points. Finally, each sample was dispersed in 200 µL of cyclohexane for later use. Synthesis of NaErF 4 @NaYF 4 @NaYF 4 @NaNdF 4 (80.0 µmol/min and 6.7 µmol/min, d(Y@Y) = 6.8 nm) core-multishell nanocrystals. Firstly, NaErF 4 @NaYF 4 core-shell nanocrystals were synthesized by the same method as above. NaErF 4 @NaYF 4 @NaYF 4 (d(Y@Y) = 6.8 nm) core-shell nanocrystals were synthesized by a modified one-pot sequential layer-by-layer epitaxial growth method of the literature 41 . The whole synthesis process is mainly divided into two steps. The first is the precursor processing process, and the second is the shell growth process. Treatment of Y-OA (0.1 M) shell precursor. Rare-earth acetate powder Y(CH 3 CO 2 ) 3 (0.665 g, 2.5 mmol), ODE (15 mL), and OA (10 mL) were mixed and added into a 50 mL three-neck flask. The mixture solution was heated to 140 o C under vacuum and magnetic agitation for 30 min to remove water and oxygen. Finally, obtain a clear precursor solution Y-OA (0.1M). Na-TFA-OA precursor solution. Na-TFA (0.544 g, 4.0 mmol) and OA (10 mL) were added to a 50 mL three-neck flask under vacuum at room temperature while maintaining magnetic agitation to remove water and oxygen. Finally, colorless and transparent precursor solution Na-TFA-OA (0.4 M) was obtained. Synthesis of NaErF 4 @NaYF 4 @NaYF 4 (d(Y@Y) = 6.8 nm) core-shell nanocrystals. The cyclohexane solution of NaErF 4 @NaYF 4 nanocrystals (2 mL), ODE (6 mL), and OA (4 mL) were added into a 50 mL three-neck flask. Under magnetic stirring, the mixture was raised to 80 ℃, and kept for 20 min to remove cyclohexane. Then, the temperature was raised to 100 ℃ in vacuo for 20 min to remove methanol, oxygen and water from the reaction system. Next, Na-TFA-OA (0.4 M) and Y-OA (0.1 M) were injected alternately under nitrogen protection at a volume ratio of 1:2. The reaction was kept for 15 min before cooling down to room temperature. The products were centrifuged and washed three times (8000 rpm, 5 min) with the mixture of ethanol and cyclohexane (v:v = 3:2). Finally, the sample was dispersed in 2 mL cyclohexane. Then, the NaErF 4 @NaYF 4 @NaYF 4 nanocrystals were used as core nanoparticles, and the outermost layer was injected with Nd shell. The synthesis of the NaErF 4 @NaYF 4 @NaYF 4 @NaNdF 4 (80.0 µmol/min and 6.7 µmol/min) nanocrystals was identical to that for core-shell nanocrystals except for the Nd shell injection rates. Physical Measurements. Transmission electron microscopy (TEM) measurements were carried out with an HT7700 field emission TEM operated at an acceleration voltage of 120 kV. Powder X-ray diffraction (XRD) results were collected on a Rigaku D/MAX-2200 attached with a rotating anode and a Cu Kα radiation source (λ = 0.15418 nm). Luminescence spectra and decay curves measurements were performed with an FS5 (Edinburgh) combined with 980 nm (MDL-III-980) diode lasers at room temperature. High-resolution transmission electron microscopy (HRTEM) images, Energy dispersive X-ray (EDX) elemental mapping and line scan analysis were carried out on JEM-ARM300F (300 kV) transmission electron microscope. Unless otherwise noted, all spectra were measured under the same experimental conditions. In addition, key experiments were repeated three times, and others were repeated twice. Declarations Data availability All the relevant data are available from the correspondence authors upon reasonable request. Source data are provided with this paper. Acknowledgments We·acknowledge·the·support from the Tsinghua Shenzhen International Graduate School-Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation (No. SZPR2023001) and Shanghai Pujiang Program (No. 22PJD025). This work was also supported by National Natural Science Foundation of China (No. 22020102003, 52302168, 62288102, 21701109 and 22371162), the National Key Research and Development Program of China (No. 2023YFF0714200), Shenzhen Medical Research Fund (No. B2302021) and Guangdong Basic and Applied Basic Research Fund (No. 2024A1515010713), and the Overseas Research Cooperation Fund of Tsinghua SIGS (No. HW2023002). We thank the Key Laboratory of Biomedical Imaging Science and System, Chinese Academy of Sciences for providing the facility and funding support. Author contributions Q.S. conceived the project. Q.S., X.Q., S.H. and H.Z. designed the experiments. X.Q. performed the computation calculations. Y.L., X.Z., X.T., R.X. and Y.S. primarily performed the experiments. Q.S., X.Q., S.H., H.Z., Y.S., Y.L., X.Z., H.J., X.T. and R.X. contributed to the data analyses and discussion. Q.S., Y.L., X.Z., X.Q. and H.J. prepared the figures. 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Supplementary Files SI.docx Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6624432","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":458901888,"identity":"7fa82beb-fbf7-49f4-9db5-51ecfb72cace","order_by":0,"name":"Qianqian Su","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuklEQVRIiWNgGAWjYDACCTBpw2AAonhI0JJGupbDJGjhn92d/OFN2Xl7c4kExgdv2xjkzQlacufsNsk5524n7pyRwGw4t43BcGcDAS0GErnbmHnbbicY3Ehgk+ZtY0gwOEBYy+bPvG3n7IFa2H8Tq2UD0PADjBuAtjATpUXiRi7IL8mJG848bAYyJAw3ENLCPyN3MzDE7OwNjicfBDJs5AnaAgY8bCCSsYEBFk3EahkFo2AUjIJRgAMAAF/JP3QOwukWAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0002-8706-6760","institution":"Shanghai University","correspondingAuthor":true,"prefix":"","firstName":"Qianqian","middleName":"","lastName":"Su","suffix":""},{"id":458901889,"identity":"887c7a16-ec7a-4d8e-b668-55bd7e9a5459","order_by":1,"name":"Yachong Liu","email":"","orcid":"","institution":"Institute of Nanochemistry and Nanobiology","correspondingAuthor":false,"prefix":"","firstName":"Yachong","middleName":"","lastName":"Liu","suffix":""},{"id":458901890,"identity":"dd9da45d-47ff-4870-881f-0605a0df22fc","order_by":2,"name":"Xi Zou","email":"","orcid":"","institution":"Shanghai University","correspondingAuthor":false,"prefix":"","firstName":"Xi","middleName":"","lastName":"Zou","suffix":""},{"id":458901891,"identity":"2b0f389a-89a5-429a-b071-78abbae3f8b1","order_by":3,"name":"Xinle Tian","email":"","orcid":"","institution":"Shanghai University","correspondingAuthor":false,"prefix":"","firstName":"Xinle","middleName":"","lastName":"Tian","suffix":""},{"id":458901892,"identity":"9bf09dca-693e-45d3-8217-e6ec55c1d5b0","order_by":4,"name":"Ruizhe Xiao","email":"","orcid":"","institution":"The High School Attached to Hunan Normal University","correspondingAuthor":false,"prefix":"","firstName":"Ruizhe","middleName":"","lastName":"Xiao","suffix":""},{"id":458901893,"identity":"78c21ee5-9193-452c-881c-1c6fd8ef6904","order_by":5,"name":"Yan Su","email":"","orcid":"","institution":"Genome Institute of Singapore","correspondingAuthor":false,"prefix":"","firstName":"Yan","middleName":"","lastName":"Su","suffix":""},{"id":458901894,"identity":"b930588c-20b9-40e6-9660-faf93d7ea81b","order_by":6,"name":"Hao Jiang","email":"","orcid":"","institution":"Fujian Normal University","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Jiang","suffix":""},{"id":458901895,"identity":"5ab886c3-58b5-4e46-9674-72f6d08adca1","order_by":7,"name":"Xian Qin","email":"","orcid":"https://orcid.org/0000-0001-8569-7721","institution":"National University of Singapore","correspondingAuthor":false,"prefix":"","firstName":"Xian","middleName":"","lastName":"Qin","suffix":""},{"id":458901896,"identity":"f2a8c95f-9573-4ce8-99d5-8591b9bc7e37","order_by":8,"name":"Sanyang Han","email":"","orcid":"https://orcid.org/0000-0001-7414-7193","institution":"Shenzhen International Graduate School, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Sanyang","middleName":"","lastName":"Han","suffix":""},{"id":458901897,"identity":"737fa7d7-791e-43e4-be79-1a66dd4b8c89","order_by":9,"name":"Hongjie Zhang","email":"","orcid":"","institution":"Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Hongjie","middleName":"","lastName":"Zhang","suffix":""}],"badges":[],"createdAt":"2025-05-09 02:50:39","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6624432/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6624432/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83114979,"identity":"cbe6111b-20c9-4069-9e34-d237c308eecf","added_by":"auto","created_at":"2025-05-20 07:58:35","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":255498,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSchematic illustration of misfit strain enhanced substitutional lanthanide migration in anisotropic core-shell nanocrystals. \u003c/strong\u003e(\u003cstrong\u003ea\u003c/strong\u003e) Schematic representation of β-NaErF\u003csub\u003e4\u003c/sub\u003e utilized as the core for directional epitaxial growth of NaNdF\u003csub\u003e4\u003c/sub\u003e, highlighting the varying lattice mismatches between the core and shell on the (0001) and (1000) facets of the NaErF\u003csub\u003e4\u003c/sub\u003e core. (\u003cstrong\u003eb\u003c/strong\u003e) Schematic representation of the metastable interface with significant misfit strain, driving preferential lanthanide migration from the core area to the outer shell, indicating a long-range strain relaxation dynamic.\u003c/p\u003e","description":"","filename":"image1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/ea04d8be6b1f78735a157548.jpeg"},{"id":83114978,"identity":"b2e6646c-f602-4b30-b8ac-f9ec9f5f602b","added_by":"auto","created_at":"2025-05-20 07:58:35","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":638456,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eLong-range cation migration. \u003c/strong\u003e(\u003cstrong\u003ea\u003c/strong\u003e) Schematics of the formation process of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e core-shell-shell nanostructure. (\u003cstrong\u003eb\u003c/strong\u003e, \u003cstrong\u003ec\u003c/strong\u003e) TEM images, high-resolution TEM images (inset), and EDX elemental mapping of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e and NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min) nanocrystals. (\u003cstrong\u003ed\u003c/strong\u003e) EDX line scan analysis of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min) nanocrystals. (\u003cstrong\u003ee\u003c/strong\u003e) EDX elemental mapping of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4 \u003c/sub\u003e(6.7 μmol/min, the thickness of two layer of Y = 6.8 nm) nanocrystals. (\u003cstrong\u003ef\u003c/strong\u003e,\u003cstrong\u003e g\u003c/strong\u003e) Emission spectra and luminescence decay curves of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e and NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min) nanocrystals. (\u003cstrong\u003eh\u003c/strong\u003e) Schematic representation of substitutional diffusion and the mechanism through which misfit strain enhances this process, facilitating long-range strain relaxation.\u003c/p\u003e","description":"","filename":"image2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/6ff205fbabe5c22bfaa9e992.jpeg"},{"id":83116600,"identity":"024f373a-2533-4200-a4fd-d2ec217175c1","added_by":"auto","created_at":"2025-05-20 08:14:35","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":951753,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDiffusion dynamics and nanocrystals growth.\u003c/strong\u003e TEM images (\u003cstrong\u003ea\u003c/strong\u003e-\u003cstrong\u003ed\u003c/strong\u003e), HRTEM images and IFFT analysis (\u003cstrong\u003ee\u003c/strong\u003e-\u003cstrong\u003eh\u003c/strong\u003e), and EDX elemental mapping along with atomic simulation of lanthanide migration (\u003cstrong\u003ei\u003c/strong\u003e-\u003cstrong\u003el\u003c/strong\u003e) for the as-synthesized NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e nanocrystals at varying Nd shell injection rates of 80.0 μmol/min, 40.0 μmol/min, 20.0 μmol/min, 13.3 μmol/min. The enlargement of dislocation misfits in regions E, F, G, and H is shown (E1-H1: corresponding IFFT patterns).\u003c/p\u003e","description":"","filename":"image3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/416d028ab5bd1394a22d11e5.jpeg"},{"id":83115448,"identity":"f309d66e-53a9-46e6-a76f-ff11aea524c5","added_by":"auto","created_at":"2025-05-20 08:06:35","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":498969,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eUniversality of lanthanide migration.\u003c/strong\u003e (\u003cstrong\u003ea\u003c/strong\u003e) TEM images of as-synthesized NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaLnF\u003csub\u003e4\u003c/sub\u003e (Ln = Lu, Y, Tb, Gd, Eu, Nd, Pr, and Ce) nanocrystals with corresponding injection rates about 6.7 μmol/min (Lu), 6.7 μmol/min (Y), 6.7 μmol/min (Tb), 6.7 μmol/min (Gd), 6.7 μmol/min (Eu), 6.7 μmol/min (Nd), 13.3 μmol/min (Pr), 20 μmol/min (Ce). (\u003cstrong\u003eb\u003c/strong\u003e-\u003cstrong\u003ef\u003c/strong\u003e) EDX elemental mapping of as-synthesized NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaLuF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaTbF\u003csub\u003e4\u003c/sub\u003e (6.7 μmol/min), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaEuF\u003csub\u003e4 \u003c/sub\u003e(6.7 μmol/min), and NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaCeF\u003csub\u003e4\u003c/sub\u003e (20.0 μmol/min) nanocrystals.\u003c/p\u003e","description":"","filename":"image4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/48a0808293ae3d5aa5ae6763.jpeg"},{"id":83116890,"identity":"67ba9b1d-d3c4-487f-851d-cd826d6520d9","added_by":"auto","created_at":"2025-05-20 08:22:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3275976,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/0e36198e-0620-45d5-bac3-e03ff03d91c8.pdf"},{"id":83114996,"identity":"baad7c52-cb37-4fbc-bb1d-18843f9e338a","added_by":"auto","created_at":"2025-05-20 07:58:36","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":66599656,"visible":true,"origin":"","legend":"Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure","description":"","filename":"SI.docx","url":"https://assets-eu.researchsquare.com/files/rs-6624432/v1/eb81297b564a711b9180d2bb.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure","fulltext":[{"header":"Introduction","content":"\u003cp\u003eStrain engineering has emerged as a crucial strategy for directing heteroepitaxial growth and modulating the optical, electrical, catalytic, and magnetic functionalities of advanced nanomaterials\u003csup\u003e\u003cspan additionalcitationids=\"CR2 CR3 CR4 CR5 CR6\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. However, interfacial strain is often thermodynamically unstable and may be partially alleviated through ion diffusion, defect formation, or phase transition, which drive the system from a metastable state to a more stable configuration\u003csup\u003e\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. Even after partial relaxation, residual strain can substantially impact the structural integrity of the epitaxial shell, which in turn affects the overall properties of the resulting nanocrystals.\u003c/p\u003e \u003cp\u003eIn particular, previous studies have highlighted that cation inter-diffusion at interfaces or grain boundaries\u0026mdash;driven by surface energy minimization, defect density gradients, or dopant redistribution\u0026mdash;can significantly influence the emission efficiency, catalytic activity, and magnetic coercivity of heterostructured nanocrystals\u003csup\u003e\u003cspan additionalcitationids=\"CR12 CR13 CR14 CR15\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. These findings indicate that precisely regulated interfacial ion migration can serve as a powerful tool to tailor nanocrystal functionalities, offering exciting prospects for next-generation technologies in optoelectronics\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e,\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e, energy conversion\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e,\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e, quantum technologies\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e,\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e, and biomedical engineering\u003csup\u003e\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e. However, limited attention has been directed toward understanding how strain affects the interface integrity of core-shell nanoparticles\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e, leaving the relationship between interfacial strain and cation diffusion dynamics poorly understood\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. Therefore, controlling cation migration through interfacial strain engineering is essential for unlocking the full potential of core-shell nanoparticles, enabling the development of nanomaterials with tailored properties and driving innovations across diverse applications in nanotechnology.\u003c/p\u003e \u003cp\u003eHere, we choose lanthanide-doped fluoride heterostructured nanocrystals as model systems and present direct evidence of lanthanide migration across interfaces in multilayered nanocrystals, specifically NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaLnF\u003csub\u003e4\u003c/sub\u003e (Ln\u0026thinsp;=\u0026thinsp;Lu, Y, Tb, Gd, Eu, Nd, Pr, and Ce). Mechanistic investigation reveals that lattice mismatch between different layers plays a pivotal role in regulating the diffusion dynamics of the lanthanide dopants. Notably, tensile strain exerted by shell layers containing large-size lanthanides facilitates lanthanide migration from the core to the surface or near-surface area, with diffusion lengths exceeding 10 nm. Moreover, we demonstrate that lanthanide diffusion can be regulated through interfacial strain engineering by controlling the type of nanocrystal precursors and the deposition rates during shell growth. This regulation enables precise control over lanthanide distribution and ultimately the optical performance of the nanostructures.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cb\u003eTheoretical basis of lanthanide migration.\u003c/b\u003e In given heterostructures, lattice mismatch often induces misfit strain at interfaces, with larger mismatches typically leading to greater strain\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e. To theoretically study the impact of interfacial misfit strain on crystal structure at the atomic level, we selected a hexagonal-phase NaErF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e core-shell crystal characterized by a large lattice mismatch and low lattice symmetries (Supplementary Fig.\u0026nbsp;1). Upon lattice optimization, the calculated lattice mismatch between the NaErF\u003csub\u003e4\u003c/sub\u003e (0001) facet and the NaNdF\u003csub\u003e4\u003c/sub\u003e (0001) facet is approximately 2.74%, considerably smaller than that calculated for the (1000) facet (~\u0026thinsp;6.15%, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea). Note that these two facets were chosen for their low surface energies\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e. We calculated the adsorption energies of a Nd atom on the (0001) and (1000) facets of the NaErF\u003csub\u003e4\u003c/sub\u003e by first-principles calculations based on density functional theory (DFT). For the (0001) facet, only minor changes in the adsorption energies were observed between the strain-free and moderately stretched surfaces. In contrast, the adsorption energies on the stretched (1000) facet increased significantly compared to the strain-free condition. Specifically, for the (1000) facet, Nd atoms preferentially adsorbed on the top of the surface Er atoms, exhibiting a high adsorption energy of -4.16 eV without external strain (Supplementary Table\u0026nbsp;1). Notably, this energy increased by 46% under applied tensile strain of 6.15%. This energetic change suggests that misfit strain at different interfaces alters the local electronic environment and atomic arrangement, thereby impacting the binding strength between the adsorbate and substrate (Supplementary Figs.\u0026nbsp;2\u0026ndash;4). Furthermore, the strain-strengthened binding indicates that lattice misfit elevates the energy of the (1000) facet. This increase in energy likely facilitates the dissolution of the (1000) facet, thereby promoting the growth of the thermodynamically more stable (0001) facet through intraparticle diffusion processes\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e. By employing different lanthanide ions (Lu, Er, Y, Tb, Gd, Eu, Nd, Pr, and Ce), it is feasible to modulate the misfit strain at distinct interfaces within a single core-shell nanocrystal (Supplementary Tables\u0026nbsp;2\u0026ndash;5). In this regard, we hypotheses that lanthanides adsorbed on the metastable interface with substantial misfit strain have high likelihood to migrate toward the (0001) facet or the core area to release interfacial strain (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb).\u003c/p\u003e \u003cp\u003e \u003cb\u003eLanthanide migration of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaNdF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e. To validate our hypothesis, we designed a NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e core-shell-shell nanostructure (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). Given the similar lattice constant of NaErF\u003csub\u003e4\u003c/sub\u003e and NaYF\u003csub\u003e4\u003c/sub\u003e crystals, NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e core-shell nanoparticles were first chosen for their negligible interfacial stain of ~\u0026thinsp;0.5%. As anticipated, a NaYF\u003csub\u003e4\u003c/sub\u003e shell exhibited a seamless coating on the NaErF\u003csub\u003e4\u003c/sub\u003e nanocrystals (Supplementary Fig.\u0026nbsp;5). Moreover, energy dispersive X-ray (EDX) elemental mapping analysis indicated an even distribution of Er\u003csup\u003e3+\u003c/sup\u003e and Y\u003csup\u003e3+\u003c/sup\u003e ions in the core and shell regions, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb). We next coated a NaNdF\u003csub\u003e4\u003c/sub\u003e shell on the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e core-shell nanoparticles, by hot injection at a low injection rate of approximately 6.7 \u0026micro;mol/min, corresponding to an injection time of 60 min, to study the lanthanide diffusion driven by a large lattice mismatch between NaYF\u003csub\u003e4\u003c/sub\u003e and NaNdF\u003csub\u003e4\u003c/sub\u003e layers. TEM images revealed that the resulting NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e multilayered nanoparticles crystallized in a rod-like structure (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec). We also collected samples at intervals of 1, 5, 10, 20, 30, and 60 minutes to examine morphological changes during shell growth. TEM images showed that NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e nanoparticles evolved from quasi-sphere to quasi-rhombuses and then to rod-like nanocrystals (Supplementary Fig.\u0026nbsp;6). Notably, elemental mapping analysis revealed that Nd\u003csup\u003e3+\u003c/sup\u003e ions were mainly located at the opposite ends of the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanoparticles, indicating preferential precursor deposition and growth on the largely exposed, high-energy (1000) surface of the seed nanoparticles\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e,\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eNotably, we found that Y\u003csup\u003e3+\u003c/sup\u003e ions were not evenly wrapped around the Er cores, but diffused to the two ends of the nanorods, and distributed uniformly in the Nd shell (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec, d). Apart from the intermixing between Y\u003csup\u003e3+\u003c/sup\u003e and Nd\u003csup\u003e3+\u003c/sup\u003e ions in the shell layers, elemental mapping also showed a substantial amount of Er\u003csup\u003e3+\u003c/sup\u003e ions diffusing across the interfaces to the Nd layer (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec). A long-distance migration of approximately 13 nm along the [0001] direction was estimated in the hetero-nanostructures under study. To further evaluate the interface strain-induced diffusion length, we synthesized a series of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e nanocrystals with different NaYF\u003csub\u003e4\u003c/sub\u003e-spacer thicknesses. Surprisingly, we found that the core Er\u003csup\u003e3+\u003c/sup\u003e could diffuse to the Nd shell even when the thickness of the Y spacer was up to 6.8 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee). Considering that the misfit strain originates from the Nd-Y interface, the diffusion of lanthanides from the core area to the outer shell suggested a long-range nature of strain relaxation dynamics.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe intermixing of Nd\u003csup\u003e3+\u003c/sup\u003e, Y\u003csup\u003e3+\u003c/sup\u003e, and Er\u003csup\u003e3+\u003c/sup\u003e ions significantly shortened the distance between the Nd\u003csup\u003e3+\u003c/sup\u003e and Er\u003csup\u003e3+\u003c/sup\u003e ions, which could trigger strong resonant energy transfer from the Er\u003csup\u003e3+\u003c/sup\u003e to Nd\u003csup\u003e3+\u003c/sup\u003e ions upon light excitation\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e,\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e. By directly pumping the Er\u003csup\u003e3+\u003c/sup\u003e emitters, the spectroscopy measurements showed markedly quenched photoluminescence and shortened lifetime of Er\u003csup\u003e3+\u003c/sup\u003e in the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e nanoparticles compared with that observed in the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanoparticles, again confirming the close proximity of Nd\u003csup\u003e3+\u003c/sup\u003e to Er\u003csup\u003e3+\u003c/sup\u003e ions (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ef, g, and Supplementary Fig.\u0026nbsp;7).\u003c/p\u003e \u003cp\u003eWe next investigated the mechanism behind long-range cation migration in multilayered nanocrystals. It should be noted that lattice vacancies create empty sites within the crystal structure, which can serve as pathways for ions to move (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh, left diagram). In this regard, the rate of substitutional diffusion is influenced by two primary factors: the ease of vacancy formation and the mobility of atoms into those vacancies\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e,\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e. Interfacial misfit strain at interfaces in the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e core-shell system is expected to promote lanthanide diffusion as the substantial lattice mismatch between NaYF\u003csub\u003e4\u003c/sub\u003e and NaNdF\u003csub\u003e4\u003c/sub\u003e introduces structural distortions that facilitate vacancy creation (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh, right diagram).\u003c/p\u003e \u003cp\u003eWe then modulated cation diffusion through interfacial strain engineering by adjusting the Nd precursor injection rate, thereby influencing the diffusion dynamics and growth behavior at the core-shell interface (Supplementary Fig.\u0026nbsp;8). X-ray diffraction (XRD) patterns confirmed that all samples maintained a pure hexagonal crystal structure (Supplementary Fig.\u0026nbsp;9). The diffraction peaks of the core-multishell structures shifted to lower diffraction angles relative to the core pattern, demonstrating the incoherent epitaxial growth with compressively strained shell\u003csup\u003e\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e. In addition, the asymmetrical broadening of these diffraction peaks indicates an uneven distribution of lattice spacings due to the formation of lattice defects or distortion in the heterostructured crystal.\u003c/p\u003e \u003cp\u003eTEM images revealed patch-like Nd shell fragments on the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanocrystals at an injection rate of 80.0 \u0026micro;mol/min over 5 minutes (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea-d and Supplementary Fig.\u0026nbsp;10). As the injection rate decreased, the nanoparticle morphology evolved from star-like (80.0, 40.0, 20.0 \u0026micro;mol/min) to a triangular (13.3 \u0026micro;mol/min) and finally to rod-like shape (6.7 \u0026micro;mol/min). The crystal structure and lattice mismatch in nanocrystals is effectively visualized through high-resolution TEM (HRTEM) characterization\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. HRTEM also showed that NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanocrystals initially exhibited a single crystal structure (Supplementary Fig.\u0026nbsp;11). Upon introducing Nd\u003csup\u003e3+\u003c/sup\u003e ions, significant structural changes were observed. At high injection rates, the nanocrystals displayed a polycrystalline structure (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ee, f, and Supplementary Figs.\u0026nbsp;12\u0026ndash;14) and transformed to a single crystal-like structure at slow injection rates (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eg, h). We also examined the interfacial regions using HRTEM and inverse fast Fourier transform (IFFT) analysis and found discontinuities in lattice fringes of regions e and f, indicative of lattice mismatch and strain, while lattice fringes became more orderly at lower injection rates (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eE-H and Supplementary Fig.\u0026nbsp;15). These results indicate that variations in the injection rate affect growth dynamics and precursor deposition, which is consistent with the previous study\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eElemental mapping of these nanoparticles revealed that the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e core maintains a nearly spherical shape (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). Following the rapid injection of the Nd precursor, the Er core retains its shape, while the distribution of Y\u003csup\u003e3+\u003c/sup\u003e ions of the interlayer begins to resemble that of the outer Nd shell (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ei, j, and Supplementary Fig.\u0026nbsp;16). In contrast, at low injection rates, the shape of Er core increasingly mimics that of the Nd shell, and the distribution of interlayer Y\u003csup\u003e3+\u003c/sup\u003e ions tends to overlap with Nd shell (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ek, l, and Supplementary Fig.\u0026nbsp;16). High injection rates can lead to uneven precursor distribution and confined growth, limiting cation diffusion and preventing effective diffusion to stable sites. In contrast, low injection rates facilitate uniform distribution of precursors, allowing pre-deposited ions to diffuse toward stable sites sufficiently before the arrival of the next batch of precursors. Thus, the interplay between injection rate, growth kinetics, and surface energy critically determines the morphological changes of the nanocrystals and diffusion of cations. These findings also suggest that misfit strain relaxation through ion diffusion is favored, likely due to increased defects facilitating ion movement and lowered migration energy barriers at slow injection rates.\u003c/p\u003e \u003cp\u003eFor spectroscopy measurements, we found that the luminescence from Er\u003csup\u003e3+\u003c/sup\u003e emitters was markedly attenuated as the injection rates decreased (Supplementary Fig.\u0026nbsp;17). For instance, nanoparticles synthesized at an injection rate of 40.0 \u0026micro;mol/min exhibited approximately 29-fold and 100-fold higher luminescence at 500\u0026ndash;700 nm and 1400\u0026ndash;1600 nm, respectively, compared with that recorded in the nanoparticle prepared at an injection rate of 6.7 \u0026micro;mol/min (Supplementary Fig.\u0026nbsp;18). Note that the corresponding luminescence lifetime gradually decreased as the injection rate decreased. These findings corroborated enhanced energy transfer from the Er\u003csup\u003e3+\u003c/sup\u003e ions to their neighboring Nd\u003csup\u003e3+\u003c/sup\u003e ions and strong lanthanide intermixing in nanoparticles.\u003c/p\u003e \u003cp\u003e \u003cb\u003eUniversality of lanthanide migration.\u003c/b\u003e By taking advantage of lanthanide contraction, we systematically studied the effects of interfacial strain and epitaxial growth kinetics on lanthanide diffusion. Specifically, the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanoparticles were coated with Lu, Y, Tb, Gd, Eu, Pr and Ce shells, generating misfit strains of -2.0%, 0%, 1.4%, 2.0%, 2.4%, 6.0%, and 7.0%, respectively. TEM images revealed that minor misfit strain on the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e surface promoted a coherent epitaxial growth, while higher misfit strain levels induced non-coherent growth (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea), which is also consistent with the previous report\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e,\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e. In the case of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanoparticles, the outmost Y shell, which applied zero strain, maintained a single-crystal structure, with minimal Er\u003csup\u003e3+\u003c/sup\u003e ion migration (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, and injection rate: 6.7 \u0026micro;mol/min). In contrast, when applying compressive strain on the Er core through the coating of Lu shell, we observed that the strain barely affected the diffusion of Er\u003csup\u003e3+\u003c/sup\u003e but did promote Y\u003csup\u003e3+\u003c/sup\u003e diffusion, as evidenced by the similarity of its distribution to that of the outer Nd shell under slow growth conditions (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec). Interestingly, the Tb shell, with a misfit strain of 1.4%, triggered a significant long-range Er\u003csup\u003e3+\u003c/sup\u003e migration under slow growth rates (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed, and injection rate: 6.7 \u0026micro;mol/min), suggesting that tensile strain plays a primary role in governing diffusion dynamics. For the Eu shell, which applied moderate strain, we observed that the distribution of Er\u003csup\u003e3+\u003c/sup\u003e closely aligned with the outer Nd shell, even at a modest growth rate of 6.7 \u0026micro;mol/min (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ee). In the case of Pr and Ce shells, the large lattice mismatches at Y-Pr and Y-Ce interfaces hindered the uniform formation of nanoparticle. Nevertheless, these samples exhibited rod-like morphologies and intense Y\u003csup\u003e3+\u003c/sup\u003e diffusion, though Er\u003csup\u003e3+\u003c/sup\u003e diffusion was limited by relatively higher growth rates (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ef, 20.0 \u0026micro;mol/min, and Supplementary Fig.\u0026nbsp;19).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eTaken together, significant lanthanide diffusion was detected with Tb, Eu, Gd, Nd, Pr and Ce coatings, while Y-coated nanoparticles exhibited almost no diffusion (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and Supplementary Figs.\u0026nbsp;19\u0026ndash;21). Slow epitaxial growth facilitated lanthanide diffusion, whereas compressive strain and rapid shell growth could suppress lanthanide diffusion to some extent. The photoluminescence and lifetimes of the nanocrystals correlated with the distribution of the lanthanide ions (Supplementary Figs.\u0026nbsp;22\u0026ndash;25). High lattice mismatches introduced substantial strain, creating vacancies and defects that facilitate ion diffusion by lowering energy barriers and increasing defect density. Consequently, larger mismatches create a thermodynamically favorable environment for ion diffusion, allowing ions to migrate to energetically favorable sites and alleviate local strain. In contrast, smaller mismatches, such as those involving Y, may not promote significant diffusion due to zero mismatch strain, resulting in more stable configurations with limited ion movement.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn summary, we systematically investigated the effect of lattice mismatch-induced interfacial strain on heterogeneous epitaxial growth and ion diffusion within nanolattices. Using hexagonal-phase core-shell NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaLnF\u003csub\u003e4\u003c/sub\u003e (Ln\u0026thinsp;=\u0026thinsp;Lu, Y, Tb, Gd, Eu, Nd, Pr and Ce) nanocrystals as model systems, we demonstrated that lanthanide diffusion across interfaces can be effectively controlled through misfit strain engineering, involving adjustments of shell growth dynamics and the magnitude of misfit strain (-2.0\u0026ndash;7.0%). Specifically, in NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e nanocrystals with a substantial misfit strain of 5.1%, we observed that Er\u003csup\u003e3+\u003c/sup\u003e ions in the core and Y\u003csup\u003e3+\u003c/sup\u003e ions in the spacer migrated over 10 nm to the outer Nd shell, mainly along the (0001) crystallographic direction. These findings not only enhance our understanding of interfacial strain relaxation dynamics but also enable precise control over ion diffusion in heterostructure nanolattices, advancing the development of strain-engineered nanocrystals with intriguing electronic, optical, magnetic, or catalytic properties.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e \u003cb\u003eMaterials.\u003c/b\u003e Y(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Nd(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Gd(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Tb(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), LuCl\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Er(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Ce(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Eu(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), Pr(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;xH\u003csub\u003e2\u003c/sub\u003eO (99.9%), NaOH (\u0026gt;\u0026thinsp;98%), NH\u003csub\u003e4\u003c/sub\u003eF (\u0026gt;\u0026thinsp;98%), oleic acid (OA, 90%), 1-octadecene (ODE, 90%), sodium oleate and sodium trifluoroacetate (Na-TFA) were all purchased from Sigma-Aldrich. Hydrochloric acid (AR), absolute methanol (AR), cyclohexane (AR) and ethanol (AR) were obtained from Sinopharm Chemical Reagent Co., Ltd. All chemicals were used as received without further purification.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSynthesis of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003ecore nanocrystals.\u003c/b\u003e NaErF\u003csub\u003e4\u003c/sub\u003e core nanocrystals were prepared by a modified literature procedure\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e. A total of 4 mL of rare-earth acetate Er(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (0.275 g, 0.80 mmol) aqueous solution, oleic acid (10 mL), and octadecene (10 mL) were added to a 50 mL three-neck flask, and the mixture was stirred and heated to 150 \u003csup\u003eo\u003c/sup\u003eC (750 rpm/min) for 1.5 h, and then cooled down to room temperature naturally. Next, the flask was transferred to the heating mantle, and then sodium oleate (0.761 g, 2.50 mmol) was added. The reaction was maintained at 100 \u003csup\u003eo\u003c/sup\u003eC under vacuum condition for 1 h. Subsequently, NH\u003csub\u003e4\u003c/sub\u003eF powder (0.148 g, 4.00 mmol) was added to the three-neck flask under nitrogen, and then slowly heated to 160 \u003csup\u003eo\u003c/sup\u003eC for 1.5 h. After vacuumizing for 10 min, the reaction was heated to 320 \u003csup\u003eo\u003c/sup\u003eC and kept at this temperature under nitrogen protection for 0.5 h before cooling down to room temperature. The resulting mixture was centrifugated and washed three times (8000 rpm, 5 min) using ethanol/cyclohexane (v/v\u0026thinsp;=\u0026thinsp;3/2), and finally dispersed in 8 mL cyclohexane prior to being used for shell coating. The synthesis of NaNdF\u003csub\u003e4\u003c/sub\u003e and NaErF\u003csub\u003e4\u003c/sub\u003e:50%Nd was identical to that for NaErF\u003csub\u003e4\u003c/sub\u003e nanoparticles except for using the different compositions of dopants.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSynthesis of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003ecore-shell nanocrystals.\u003c/b\u003e The core-shell nanocrystals were synthesized by a modified method\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e,\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e\u003c/sup\u003e. The obtained NaErF\u003csub\u003e4\u003c/sub\u003e core nanocrystals were used as seeds for the shell coating. A 2 mL aqueous solution of Y(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (0.106 g, 0.40 mmol), oleic acid (4 mL) and octadecene (6 mL) were added to a 50 mL three-neck flask. The temperature was heated to 150 \u003csup\u003eo\u003c/sup\u003eC and maintained at this temperature for 1.5 h (750 rpm/min) before cooling down to 50 \u003csup\u003eo\u003c/sup\u003eC. Then, 4.4 mL methanol solution of NH\u003csub\u003e4\u003c/sub\u003eF (0.050 g, 1.36 mmol) and NaOH (0.040 g, 1.00 mmol) was quickly added and kept for 0.5 h, and then slowly heated to 80 \u003csup\u003eo\u003c/sup\u003eC for 0.5 h to remove methanol. At the same time, NaErF\u003csub\u003e4\u003c/sub\u003e (4 mL) dispersed in cyclohexane was added into a 50 mL three-neck flask, then oleic acid (4 mL) and octadecene (6 mL) were added and heated to 80 \u003csup\u003eo\u003c/sup\u003eC to remove cyclohexane. Then, the temperature was slowly increased to 100 \u003csup\u003eo\u003c/sup\u003eC for 30 min \u003cem\u003ein vacuo\u003c/em\u003e. After the end, the temperature was heated at a constant rate to 310 \u003csup\u003eo\u003c/sup\u003eC in a nitrogen environment. The treated shell precursor was injected at a uniform rate for 40.0 \u0026micro;mol/min (10 min), and then the reaction was cooled down to room temperature. The sample was centrifugally washed three times (8000 rpm, 5 min) using ethanol/cyclohexane (v/v\u0026thinsp;=\u0026thinsp;3/2), and finally dispersed in 4 mL cyclohexane.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSynthesis of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaNdF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003ecore-multishell nanocrystals.\u003c/b\u003e The preparation of the above-mentioned and other core-multishell nanocrystals, including NaErF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (Er@Nd) NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Nd), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaTbF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Tb), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Y), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaGdF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Gd), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaLuF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Lu), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaCeF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Ce), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaPrF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Pr), NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaEuF\u003csub\u003e4\u003c/sub\u003e (Er@Y@Eu), were the same as that for core-shell nanocrystals except for the use of a shell with different lanthanide ions and shell injection rates. The preparation of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (6.7 \u0026micro;mol/min, sampling time: 1 min\u0026thinsp;\u0026minus;\u0026thinsp;60 min) core-multishell nanocrystals were the same as that for core-shell nanocrystals except for 0.5 mL of stock solution was taken at fixed time points. Finally, each sample was dispersed in 200 \u0026micro;L of cyclohexane for later use.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSynthesis of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaNdF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e(80.0 \u0026micro;mol/min and 6.7 \u0026micro;mol/min, d(Y@Y)\u0026thinsp;=\u0026thinsp;6.8 nm) core-multishell nanocrystals.\u003c/b\u003e Firstly, NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e core-shell nanocrystals were synthesized by the same method as above. NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e (d(Y@Y)\u0026thinsp;=\u0026thinsp;6.8 nm) core-shell nanocrystals were synthesized by a modified one-pot sequential layer-by-layer epitaxial growth method of the literature\u003csup\u003e\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e. The whole synthesis process is mainly divided into two steps. The first is the precursor processing process, and the second is the shell growth process.\u003c/p\u003e \u003cp\u003e \u003cb\u003eTreatment of Y-OA (0.1 M) shell precursor.\u003c/b\u003e Rare-earth acetate powder Y(CH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e (0.665 g, 2.5 mmol), ODE (15 mL), and OA (10 mL) were mixed and added into a 50 mL three-neck flask. The mixture solution was heated to 140 \u003csup\u003eo\u003c/sup\u003eC under vacuum and magnetic agitation for 30 min to remove water and oxygen. Finally, obtain a clear precursor solution Y-OA (0.1M).\u003c/p\u003e \u003cp\u003e \u003cb\u003eNa-TFA-OA precursor solution.\u003c/b\u003e Na-TFA (0.544 g, 4.0 mmol) and OA (10 mL) were added to a 50 mL three-neck flask under vacuum at room temperature while maintaining magnetic agitation to remove water and oxygen. Finally, colorless and transparent precursor solution Na-TFA-OA (0.4 M) was obtained.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSynthesis of NaErF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e@NaYF\u003c/b\u003e \u003csub\u003e \u003cb\u003e4\u003c/b\u003e \u003c/sub\u003e \u003cb\u003e(d(Y@Y)\u0026thinsp;=\u0026thinsp;6.8 nm) core-shell nanocrystals.\u003c/b\u003e The cyclohexane solution of NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanocrystals (2 mL), ODE (6 mL), and OA (4 mL) were added into a 50 mL three-neck flask. Under magnetic stirring, the mixture was raised to 80 ℃, and kept for 20 min to remove cyclohexane. Then, the temperature was raised to 100 ℃ \u003cem\u003ein vacuo\u003c/em\u003e for 20 min to remove methanol, oxygen and water from the reaction system. Next, Na-TFA-OA (0.4 M) and Y-OA (0.1 M) were injected alternately under nitrogen protection at a volume ratio of 1:2. The reaction was kept for 15 min before cooling down to room temperature. The products were centrifuged and washed three times (8000 rpm, 5 min) with the mixture of ethanol and cyclohexane (v:v\u0026thinsp;=\u0026thinsp;3:2). Finally, the sample was dispersed in 2 mL cyclohexane. Then, the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e nanocrystals were used as core nanoparticles, and the outermost layer was injected with Nd shell. The synthesis of the NaErF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaYF\u003csub\u003e4\u003c/sub\u003e@NaNdF\u003csub\u003e4\u003c/sub\u003e (80.0 \u0026micro;mol/min and 6.7 \u0026micro;mol/min) nanocrystals was identical to that for core-shell nanocrystals except for the Nd shell injection rates.\u003c/p\u003e \u003cp\u003e \u003cb\u003ePhysical Measurements.\u003c/b\u003e Transmission electron microscopy (TEM) measurements were carried out with an HT7700 field emission TEM operated at an acceleration voltage of 120 kV. Powder X-ray diffraction (XRD) results were collected on a Rigaku D/MAX-2200 attached with a rotating anode and a Cu Kα radiation source (λ\u0026thinsp;=\u0026thinsp;0.15418 nm). Luminescence spectra and decay curves measurements were performed with an FS5 (Edinburgh) combined with 980 nm (MDL-III-980) diode lasers at room temperature. High-resolution transmission electron microscopy (HRTEM) images, Energy dispersive X-ray (EDX) elemental mapping and line scan analysis were carried out on JEM-ARM300F (300 kV) transmission electron microscope. Unless otherwise noted, all spectra were measured under the same experimental conditions. In addition, key experiments were repeated three times, and others were repeated twice.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll the relevant data are available from the correspondence authors upon reasonable request. Source data are provided with this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe·acknowledge·the·support from the Tsinghua Shenzhen International Graduate School-Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation (No. SZPR2023001) and Shanghai Pujiang Program (No. 22PJD025). This work was also supported by National Natural Science Foundation of China (No. 22020102003, 52302168, 62288102, 21701109 and 22371162), the National Key Research and Development Program of China (No. 2023YFF0714200), Shenzhen Medical Research Fund (No. B2302021) and Guangdong Basic and Applied Basic Research Fund (No. 2024A1515010713), and the Overseas Research Cooperation Fund of Tsinghua SIGS (No. HW2023002). We thank the Key Laboratory of Biomedical Imaging Science and System, Chinese Academy of Sciences for providing the facility and funding support.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQ.S. conceived the project. Q.S., X.Q., S.H. and H.Z. designed the experiments. X.Q. performed the computation calculations. Y.L., X.Z., X.T., R.X. and Y.S. primarily performed the experiments. Q.S., X.Q., S.H., H.Z., Y.S., Y.L., X.Z., H.J., X.T. and R.X. contributed to the data analyses and discussion. Q.S., Y.L., X.Z., X.Q. and H.J. prepared the figures. Q.S., Y.L., X.Q., H.Z. and S.H wrote the manuscript with contributions from other authors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no\u0026nbsp;competing interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdditional information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSupplementary Information\u0026nbsp;\u003c/strong\u003eaccompanies this paper at http://www.nature.com/naturecommunications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eReprints and permissions information\u003c/strong\u003e is available online at http://www.nature.com/reprints.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSmith AM, Mohs AM, Nie S (2009) Tuning the optical and electronic properties of colloidal nanocrystals by lattice strain. 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Chem Mater 25:106\u0026ndash;112\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6624432/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6624432/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eInterfacial strain engineering, achieved through the precise control of lattice mismatch, holds implications for both fundamental and technological applications. However, unravelling the correlation between interfacial lattice strain and material properties at the nanoscale remains challenging due to limitation in regulating both the type and magnitude of strain at the nanoscale. Here, we observe long-distance ion migration induced by interfacial lattice strain in a series of lanthanide core-shell nanofluorides. By deliberately manipulating interfacial strain using lanthanide cations with varying ionic radii, the lattice mismatch promotes lanthanide migration across heterostructure interfaces and thus influences crystal growth dynamics and subsequent optical features. Notably, when lattice mismatch exceeds 5.1%, lanthanide ions within core nanoparticles can diffuse up to 13 nm along the [1000] crystallographic direction, crossing the interface and migrating into the shell layer of hexagonal-phase NaLnF\u003csub\u003e4\u003c/sub\u003e core-shell-shell nanolattices. Mechanistic investigation indicates that large interfacial tensile strain and slow shell growth are beneficial for strain relaxation via ion diffusion. These findings provide new insights into strain-driven ion diffusion at the nanoscale and open avenues for novel heterogeneous nanocrystals development with precisely tailored structures and confined active ions. These advancements could promote a range of applications, including bioimaging, nanocatalysis, quantum information, and many others.\u003c/p\u003e","manuscriptTitle":"Long-Distance Lanthanide Migration Regulated by Interfacial Lattice Strain in Nanostructure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-20 07:58:30","doi":"10.21203/rs.3.rs-6624432/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5ee79e88-572d-4040-93ea-971b808e61e4","owner":[],"postedDate":"May 20th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":48751134,"name":"Physical sciences/Nanoscience and technology/Nanoscale materials/Nanoparticles"},{"id":48751135,"name":"Physical sciences/Optics and photonics/Optical materials and structures/Nanoparticles"}],"tags":[],"updatedAt":"2026-05-09T09:20:17+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-20 07:58:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6624432","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6624432","identity":"rs-6624432","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}