Lattice Mismatch Research Articles

Flexible nanoimprint lithography enables high-throughput manufacturing of bioinspired microstructures on warped substrates for efficient III-nitride optoelectronic devices

III-nitride materials are of great importance in the development of modern optoelectronics, but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice mismatches. Here, we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped substrates by flexible nanoimprint lithography for promoting the light extraction capability. We design a flexible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure (NCAM) and nanoimprinted compound-eye-like SiO2 microstructure (NCSM) template, achieving a 6.4-fold increase in throughput and 25% savings in economic costs over stepper projection lithography. Compared to NCAM template, we find that the NCSM template can not only improve the light extraction capability, but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures, which suppresses the dislocations generated during coalescence, resulting in 40% reduction in dislocation density. This study provides a low-cost, high-quality, and high-throughput solution for manufacturing microstructures on warped surfaces of III-nitride optoelectronic devices.

Static and dynamic strain-driven photoluminescence tuning in rare-earth doped perovskite oxide thin films

Recently, there have been significant interest in the wide potential of photoluminescence (PL) response of rare-earth doped perovskite oxide thin films in the field of optoelectronics. This work reports an effective method to modulate the PL properties of 0.8 mol%Sm3+-doped BaTiO3 (BTO:Sm) thin films through static and dynamic strain. BTO:Sm films were epitaxially grown on LaAlO3 (LAO), 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT), MgO, and Mica single-crystal substrates by pulsed laser deposition technique. Compared with the BTO:Sm/PMN-PT heterostructure which experiences minimal lattice mismatch effect, the PL intensity of BTO:Sm/LAO and BTO:Sm/MgO is enhanced by 818.1% and 1014.7%, respectively, due to static tensile/compressive strain (-0.429% and 0.461%) during the epitaxial growth process. In the flexible BTO:Sm/Mica heterostructure, dynamic strain is introduced through mechanical bending. Compared with the unbent state, the u-type and n-type bending modes increase the relative changes in PL intensity (ΔI/I) by 599.0% and 768.5%, respectively. Particularly, BTO:Sm/Mica also exhibits a remarkable optical transmittance exceeding 75% (500–2500 nm). The enhancement of PL intensity is closely related to the adjustment of lattice strain, which changes the crystal field strength of the BTO:Sm and the radiative transition probability. This work provides valuable insights for designing future optoelectronic devices and environmental monitoring equipment. It has the potential to advance photonics and sensor technologies, paving the way for innovation and exploration in these fields.

Effect of thermal mismatch strain on the self-assembly of nanorods in YBCO/NRs nanocomposite films

This study presents a thermoelastic model to investigate the impact of thermal mismatch strain, resulting from distinct thermal expansion coefficients between the film matrix and nanorods, on the self-assembly of nanorods in YBCO/NRs nanocomposite films. An accurate understanding of thermal mismatch strain generated during nanocomposite film preparation is vital for controlling the self-assembly of artificial nanorods in such films. In this model, we calculated the total elastic energy density of the film matrix and nanorods, considering both lattice and thermal mismatch strains, to analyze the effect of thermal strain on the diameter of c-oriented nanorods in YBCO nanocomposite films. The calculated nanorod diameter values match experimentally measured values for BaZrO3 and BaSnO3 nanorods. Furthermore, compared to results that only consider lattice mismatch strain, the proposed model yields closer calculation values to experimental measurements by incorporating the impact of thermal mismatch strain. The thermal mismatch strain also affects the spacing between two adjacent nanorods, having the most profound effect on BSO nanorods compared to BZO and BHO nanorods. These findings contribute to understanding the mechanisms involved in nanorod self-assembly and provide insights to optimize the design of YBCO/NRs nanocomposite films.

Separation of wafer bonding interface from heterogenous mismatched interface achieved high quality bonded Ge-Si heterojunction

In the realm of optoelectronic integration, silicon-based Ge bonding has attracted great attention due to its advantages in short-wave infrared response and low cost. However, owing to the inherent lattice mismatch and thermal mismatch between Ge and Si, the bonded Ge-Si heterogenous interfaces encountered problems of thermal instability and high interface states. Herein, an approach of separating the bonding interface from the heterogenous interface is proposed through inserting a Ge epitaxial layer (GeEL) between the Si substrate and Ge film. This separation modifies the bonding interface to a homogenous one, alleviating the massive mismatch stress and achieving film relaxation, enhancing bonding stability in all aspects. Moreover, during 850 °C annealing, GeEL is doped via diffusion hence realizes electric filed modulation, inhibiting the carrier recombination leakage current and trap assisted tunneling in this defect-rich layer. A Ge-Si heterogenous PIN diode prepared by this bonding method has achieved a remarkable low dark current density (1.33 mA/cm2), a low ideality factor (1.11), and a high on–off ratio (106), confirming the outstanding quality of the bonded heterojunction. This work provides great prospects for higher performance, larger scale and multi-functional Si-based heterogenous material device applications.

Interfacial Engineering for Oriented Crystal Growth toward Dendrite-Free Zn Anode for Aqueous Zinc Metal Battery.

Zn deposition with a surface-preferred (002) crystal plane has attracted extensive attention due to its inhibited dendrite growth and side reactions. However, the nucleation and growth of the Zn(002) crystal plane are closely related to the interfacial properties. Herein, oriented growth of Zn(002) crystal plane is realized on Ag-modified surface that is directly visualized by in situ atomic force microscopy. A solid solution HCP-Zn (~1.10 at. % solubility of Ag, 30 °C) is formed on the Ag coated Zn foil (Zn@Ag) and possesses the same crystal structure as Zn to reduce its nucleation barrier caused by their lattice mismatch. It merits oriented Zn deposition and corrosion-resistant surface, and presents long cycling stability in symmetric cells and full cells coupled with V2O5 cathode. This work provides insights into interfacial regulation of Zn anodes for high-performance aqueous zinc metal batteries.

Interfacial Engineering for Oriented Crystal Growth toward Dendrite‐Free Zn Anode for Aqueous Zinc Metal Battery

AbstractZn deposition with a surface‐preferred (002) crystal plane has attracted extensive attention due to its inhibited dendrite growth and side reactions. However, the nucleation and growth of the Zn(002) crystal plane are closely related to the interfacial properties. Herein, oriented growth of Zn(002) crystal plane is realized on Ag‐modified surface that is directly visualized by in situ atomic force microscopy. A solid solution HCP‐Zn (~1.10 at. % solubility of Ag, 30 °C) is formed on the Ag coated Zn foil (Zn@Ag) and possesses the same crystal structure as Zn to reduce its nucleation barrier caused by their lattice mismatch. It merits oriented Zn deposition and corrosion‐resistant surface, and presents long cycling stability in symmetric cells and full cells coupled with V2O5 cathode. This work provides insights into interfacial regulation of Zn anodes for high‐performance aqueous zinc metal batteries.

One-Step Preparation of High-Stability CsPbX3/CsPb2X5 Composite Microplates with Tunable Emission.

The core-shell structure is an effective means to improve the stability and optoelectronic properties of cesium lead halide (CsPbX3 (X = Cl, Br, I)) perovskite quantum dots (QDs). However, confined by the ionic radius differences, developing a core-shell packaging strategy suitable for the entire CsPbX3 system remains a challenge. In this study, we introduce an optimized hot-injection method for the epitaxial growth of the CsPb2X5 substrate on CsPbX3 surfaces, achieved by precisely controlling the reaction time and the ratio of lead halide precursors. The synthesized CsPbX3/CsPb2X5 composite microplates exhibit an emission light spectrum that covers the entire visible range. Crystallographic analyses and density functional theory (DFT) calculations reveal a minimal lattice mismatch between the (002) plane of CsPb2X5 and the (10) plane of CsPbX3, facilitating the formation of high-quality type-I heterojunctions. Furthermore, introducing Cl- and I- significantly alters the surface energy of CsPb2X5's (110) plane, leading to an evolutionary morphological shift of grains from circular to square microplates. Benefiting from the passivation of CsPb2X5, the composites exhibit enhanced optical properties and stability. Subsequently, the white light-emitting diode prepared using the CsPbX3/CsPb2X5 composite microplates has a high luminescence efficiency of 136.76 lm/W and the PL intensity decays by only 3.6% after 24 h of continuous operation.

Magnesium ions enhanced core-shell lattice matching for Narrow-Band green emission indium phosphide QDs

Indium phosphide QDs have emerged as a promising candidate for the next generation optoelectronic applications. However, the optical performance of InP QDs still lags behind that of CdSe-based QDs, partly due to surface traps induced by the lattice mismatch between InP and ZnSe. Herein, based on (DMA)3P, we designed an alloyed inner-shell structure of InP/Zn(Mg)Se/ZnS QDs. The dual-function mechanism of the Zn(Mg)Se was revealed, which effectively mitigates the lattice mismatch between the core and shell toreduce the emission of surface defect states, resulting in narrowed emission peaks (FWHM ∼ 36 nm). While the increased band gap of Zn(Mg)Se confines the exciton delocalization from core to shell, thereby reducing the non-radiative relaxation of carriers at the defect states in the shell. This discovery provides a strategy to improve the color purity and luminescence efficiency of InP QDs. By combining blue LED chips with InP/Zn(Mg)Se/ZnS, a white light-emitting diode (QLED) with a high luminous efficiency of 63 lm/W was obtained. Furthermore, the realization of QDs arrays with 10 μm pixel dots by inkjet printing technology and the fabrication of white-light emitting Micro-LEDs by combining QDs films with Micro-LED chip arrays demonstrate the potential application of InP QDs in high-efficiency optoelectronic devices (LEDs/micro-LEDs).

Novel 3D reciprocal space visualization of strain relaxation in InSb on GaAs substrates

This study introduces the reciprocal space polar visualization (RSPV) method, a novel approach for visualizing x-ray diffraction-based reciprocal space data. RSPV allows for the precise separation of tilt and strain, facilitating their individual analysis. InSb was grown by molecular beam epitaxy on two (001) GaAs substrates—one with no misorientation (sample A) and one with 2° surface misorientation from the (001) planes (sample B). There is a substantial lattice mismatch with the substrate, and this results in the generation of defects within the InSb layer during growth. To demonstrate RSPV’s effectiveness, a comprehensive comparison of surface morphology, dislocation density, strain, and tilt was conducted. RSPV revealed previously unobserved features of the 004 InSb Bragg peak, partially explained by the presence of threading dislocations and oriented abrupt steps. Surface morphologies examined by an atomic force microscope revealed that sample B had significantly lower root mean square roughness. Independent estimates of threading dislocation density (TDD) using x-ray diffraction (XRD) and electron channelling contrast imaging confirmed that sample B exhibited a significantly lower TDD than sample A. XRD methods further revealed unequal amounts of α- and β-type threading dislocations in both samples, contributing to an anisotropic Bragg peak. RSPV is shown to be a robust method for exploring 3D reciprocal space in any crystal, demonstrating that growing InSb on misoriented GaAs produced a higher-quality crystal compared to an on-orientation substrate.

Crystallization dynamics of amorphous yttrium iron garnet thin films

Yttrium iron garnet (YIG) is a prototypical material in spintronics due to its exceptional magnetic properties. To exploit these properties, high quality thin films need to be manufactured. Deposition techniques like sputter deposition or pulsed laser deposition at ambient temperature produce amorphous films, which need a postannealing step to induce crystallization. However, not much is known about the exact dynamics of the formation of crystalline YIG out of the amorphous phase. Here, we conduct extensive time and temperature series to study the crystallization behavior of YIG on various substrates and extract the crystallization velocities as well as the activation energies needed to promote crystallization. We find that the type of crystallization as well as the crystallization velocity depend on the lattice mismatch to the substrate. We compare the crystallization parameters found in literature with our results and find excellent agreement with our model. Our results allow us to determine the time needed for the formation of a fully crystalline film of arbitrary thickness for any temperature. Published by the American Physical Society 2024

First principles study on heterogeneous interfaces of TiCu alloys through aluminum addition

This paper investigates the heterogeneous nucleation interface resulting from the addition of Al element to TiCu alloy, focusing on the essential phases Ti2Cu and TiCu. Employing first principles calculations, we explore the refinement mechanism of this interface. Initially, the lattice mismatch between Al/Ti2Cu and Al/TiCu interfaces is calculated to assess the potential for heterogeneous nucleation. Four distinct interfacial types are established following a surface convergence test. The adhesive work (Wad) and Interfacial energy (γ) are computed for each interface to ascertain their crystallization potential. Furthermore, the differential charge density (DCD) and projected density of states (PDOS) for the four interfacial types are determined to analyze bonding characteristics. Results indicate a mismatch degree of 4.09 % for Al (110)/Ti2Cu (110) and 5.29 % for Al (110)/TiCu (110). These values suggest a tendency to form a heterogeneous interface with a coherent lattice, primarily characterized by Cu-Al and Ti-Al metallic bonds. The Al-Ti2Cu interface exhibits a larger nucleation work of 2.23 J/m2 and a smaller interface energy of −53.007 J/m2. This study demonstrates that Al effectively serves as a heterogeneous nucleation center within the Ti2Cu/TiCu system, contributing to substrate phase refinement and strengthening the TiCu alloy. The optimization of these findings provides valuable insights into the alloy's microstructural evolution, facilitating the design and enhancement of advanced materials for diverse applications.

First-principles investigation on adsorption poisoning and heterogeneous nucleation mechanisms in Ca modified primary Mg2Si phase

We employed first-principles calculations to investigate the adsorption poisoning and heteroepitaxial nucleation mechanisms in the Ca modification of the primary Mg2Si phase. The extensive computations considering various factors such as lattice mismatch, interface energy, adsorption energy, charge density, work of adhesion, and interface mechanical properties, as well as comparisons of interface stacking modes reveal that Ca modification of the primary Mg2Si phase can occur through both adsorption poisoning and heteroepitaxial nucleation mechanisms simultaneously. The adsorption poisoning mechanism implies that Ca preferentially adsorbs on the Mg-terminated surfaces of Mg2Si(100) and Mg2Si(111). Meanwhile, the heteroepitaxial nucleation mechanism indicates the nucleation interface of Mg2Si(100)//CaSi2(001), where the Mg2Si(100) surface is terminated by Si, and the CaSi2(001) surface is terminated by Ca, with stacking modes of Si-Top and Si-Center. In addition, the inclusion of Ca in the primary Mg2Si phase through heteroepitaxial nucleation not only leads to refinement of the primary Mg2Si phase but also displays excellent interface mechanical properties, which suggests that Ca can be considered as an optimal modifier for the primary Mg2Si phase. This study provides a fundamental insight into the role of Ca in modifying the primary Mg2Si phase and has potential implications for the development of Si-containing magnesium alloys.

Impact of Vanadium Presence on the Mechanical and Microstructural Characteristics of a Dilute Al–Sc–Zr–Si Alloy During Isothermal Aging

In this work, we studied precipitation tendency and resulting ambient and elevated temperature properties in low-V (Al-0.06Sc-0.06Zr-0.18Si-0.05V at.%), high-V (Al-0.06Sc-0.06Zr-0.18Si-0.10V at.%), and free-V (Al-0.06Sc-0.06Zr-0.18Si at.%) alloys subjected to isothermal aging at 300 °C and 400 °C. Scanning transmission electron microscopy revealed that V incorporated into Al3(Sc, Zr) nano-precipitates during aging, forming Al3(Sc, Zr, V) while retaining the spherical morphology and L12 order. Analysis showed that V delays precipitation kinetics by interacting with vacancies, requiring longer aging for peak strength. Both V alloys demonstrated increased peak microhardness around 50–100 MPa relative to the free-V alloy after extended aging. V also reduced precipitate coarsening rates during overaging. However, creep testing exhibited no improvements to threshold stress, indicating V did not expand the precipitate/matrix lattice mismatch needed for enhanced creep resistance. The threshold stress changed from 10.2 MPa in the free-V alloy to 10.4 MPa and 10.1 MPa in the low-V and high-V alloys, respectively. Instead, V localization in the interface of nano-precipitates with matrix contributed more stability. The precipitation strengthening mechanisms in all alloys were studied using established models for L12-reinforced systems. The results showed that coherency and ordering strengthening are the primary active mechanisms.

Influence of crystallographic orientation on electronic phase separation in manganite thin films

Thin film epitaxy is a powerful method to control the strain and crystallographic orientation of the thin films using epitaxial relationship with the substrate. For colossal magnetoresistive (CMR) manganites thin films, the strong correlation between spin, charge, orbital and lattice degrees of freedom make their physical properties depend sensitively on the choice of substrate. This is especially true when considering the fact that the physical behaviors of manganites are often governed by electronic phase separation (EPS) phenomena, whose physical origin is strongly tied to lattice strain distribution. While many studies have been conducted on the substrate lattice mismatch induced strain effect, research on the substrate crystallographic orientation effect on EPS has received less attention. In this work, using (La2/3Pr1/3)5/8Ca3/8MnO3 (LPCMO) films grown on SrTiO3 (STO) substrate as a protype system, we show that EPS and its associated physical properties are strongly affected by the substrate crystallographic orientations. Specifically, we observed a clear boost of ferromagnetism in (110)-oriented LPCMO thin films with elongated EPS domains. First principles calculations show that the magnetic phase transitions of LPCMO are dominantly influenced by the spin-lattice coupling.

Highly Polarization-Deep-Ultraviolet-Sensitive β-Ga2O3 Epitaxial Films by Disrupting Rotational Symmetry and Encrypted Solar-Blind Optical Communication Application.

Ultrawide bandgap semiconductor β-Ga2O3 (4.9 eV), with its monoclinic crystal structure, exhibits distinct anisotropic characteristics both optically and electrically, making it an ideal material for solar-blind polarization photodetectors. In this work, β-Ga2O3 epitaxial films were deposited on sapphire substrates with different orientations, and the mechanisms underlying the anisotropy of these epitaxial films were investigated. Compared to c-plane sapphire, the lattice mismatch between m- or r-plane sapphire and β-Ga2O3 is more pronounced, disrupting the rotational symmetry of the films and rendering them anisotropic. Thanks to the improved anisotropy, the polarization ratio of the photodetector based on β-Ga2O3 films grown on r-plane substrates is 0.24, nearly ten times higher than that on c-plane substrates. Finally, by utilizing these polarization-sensitive photodetectors, we developed an encrypted solar-blind ultraviolet optical communication system. Our work provides a new approach to facilitate the fabrication and application of high-performance polarization-sensitive solar-blind photodetectors.

Improved crystallographic order of ScAlN/GaN heterostructures grown at low temperatures under metal rich surface conditions

Sc0.18Al0.82N/GaN with state-of-the-art x-ray diffraction figures of merit grown by metal modulated epitaxy under metal-rich conditions and a low substrate temperature of 400 °C is demonstrated to have improved crystalline order [250 arc sec for the (0002) reflection and 469 arc sec for the (101¯5)] compared to a previous state-of-the-art sample grown at a more conventional temperature of 650 °C. While both samples show a columnar structure, the higher substrate temperature sample has a good symmetric rocking curve (RC) of 229 arc sec, but unlike the lower temperature sample, the RC of the (101¯5) asymmetric reflection could not be measured, indicating a more columnar structure common among ScAlN films. Local lattice constant maps (LLCMs) from 4D-STEM depict abrupt strain relaxation within ∼2 nm from the ScAlN/GaN interface for the sample grown at Tsub = 400 °C. Since these LLCMs suggest a lattice mismatch in the a-lattice constant, and since the films show a sudden roughening, the composition for lattice match to GaN may be less than the accepted 18%–20% Sc, consistent with the average GaN lattice match from lattice constant values reported in the literature of 12%. Compared to traditional III-Nitrides, ScAlN films have substantially more screw and mixed-type threading dislocations, suggesting substantial shear forces that result in significant twist and distortion leading to orthorhombic diffraction patterns as viewed from plan-view TEM in the Tsub = 650 °C sample. These results offer the possibility of ScAlN integration into low-thermal-budget processes including CMOS but further indicate that structural understanding of ScAlN remains lacking.

Schottky diodes based on in-plane TaSi2N4–WGe2N4 and TaSi2N4–MoGe2N4 heterojunctions

Ideal metal–semiconductor interfaces in 2D lateral heterojunctions are important to realize high-performance Schottky diodes. Based on the first-principles calculations, we propose in-plane heterojunction diodes composed of the metallic TaSi2N4 and the semiconductive WGe2N4/MoGe2N4 monolayers with extremely low lattice mismatch and nearly free defect states. N-type Schottky contacts are confirmed in both TaSi2N4–WGe2N4 and TaSi2N4–MoGe2N4 heterojunctions by analyzing the energy band alignment, charge transfer, electrostatic differential potential, and effective potential. Then, the volt-ampere characteristics and the rectification effect of heterojunctions are investigated. An ultrahigh rectification ratio of 106/107 is obtained for the TaSi2N4–WGe2N4/MoGe2N4 heterojunction diode via regulating the length of the semiconductor part of the heterojunctions. The regulatory mechanism is elucidated by the asymmetrical evolutions of transmission spectra within positive and negative energy ranges. Finally, the rectification mechanism is revealed by the local density of states and the potential energy drop under bias voltages. These results provide a guideline for designing in-plane heterojunction diodes with ultrahigh rectification.

Investigating the Effect of Carbonyl Iron Powder Doping on the Microstructure and Magnetic Properties of Soft Magnetic Composites

This study proposes the thermal decomposition of salt compounds and doping of carbonyl iron powders (CIPs) to optimize the preparation of an insulating layer through the solid-phase interface reaction. First, (Fe–Si–Cr + CIPs)/ZnSO4 composite powders were synthesized using the hydrothermal method and (Fe–Si–Cr + CIPs)/ZnO·SiO2·Cr2O3 SMCs with a ZnO·SiO2·Cr2O3 composite insulation layer were prepared through heat treatment and cold pressing. The effect of the CIP doping content on the microstructure and magnetic properties of the (Fe–Si–Cr + CIPs)/ZnO·SiO2·Cr2O3 SMCs were then investigated. During the heat treatment, ZnSO4 decomposed into solid ZnO and gaseous SO2 and O2. The O2 drives the solid-phase reaction, prompting the migration of nonmagnetic Si and Cr atoms from the interior of the Fe–Si–Cr soft magnetic powder to the surface insulation layer, finally forming the ZnO·SiO2·Cr2O3 insulation layer. The doped CIPs also show good plasticity during the coating process, combining with the coating layer to fill the internal pores of SMCs. Moreover, as the particles are small with a high surface area, they increase the number of reaction sites for ZnSO4 decomposition and facilitate the growth of the composite insulation layer, promoting its uniform distribution on the surfaces of the soft magnetic powders and CIPs. The lattice mismatch between the insulation layer and soft magnetic powder is reduced while the magnetic-phase content is increased, allowing the effective doping of CIPs sin the insulation layer. The magnetic properties of SMCs can be precisely regulated by changing the doping amount of CIPs. Unlike other insulating layer–preparation strategies based on the interfacial solid-phase reaction, the proposed method exploits the high plasticity and specific surface area of CIPs and removes the lattice mismatch between the insulation layer and soft magnetic powder.

Single‐Source Evaporated High‐Quality Single‐Phase Cs3Cu2I5 Scintillator Films for High Performance X‐Ray Imaging

AbstractVacuum‐evaporated metal halides (MHs) scintillator thick films have received much attention in the X‐ray imaging field due to their excellent light yield and uniform large‐area preparation. However, the inevitable heteromorphic homologs in MHs (e.g., Copper‐based MHs (Cu‐MHs): CsCu2X3∖Cs3Cu2X5) and change of film structural backbone will result in spectral hybridization (phase purity), and the film eventually detaches (lattice mismatches). Herein, a single‐source vacuum evaporation method to prepare a thick film (≈10 µm) of Cu‐MHs (as an example) scintillators is realized: 1) Presynthesis of pure phase materials by solution method with a protective agent to ensure phase purity without precise control of component ratios in evaporation process; 2) One‐shot formation of film structural backbone avoids stress accumulation and utilize the longitudinal growth characteristics of crystalline films to obtain crystal orientations with better optical outputs. Finally, the films obtained have a light yield comparable to a partially single‐crystal (53 983 photons MeV−1) and an imaging resolution (14.1 lp mm−1) comparable to the partial template method. The detection system based on the prepared Cu‐MHs scintillator thick films exhibits good response speed and linearity in response to different X‐ray radiation intensities and exposure times. The method will further drive the application of MHs is believed.

Single [0001]-oriented zinc metal anode enables sustainable zinc batteries

The optimization of crystalline orientation of a Zn metal substrate to expose more Zn(0002) planes has been recognized as an effective strategy in pursuit of highly reversible Zn metal anodes. However, the lattice mismatch between substrate and overgrowth crystals has hampered the epitaxial sustainability of Zn metal. Herein, we discover that the presence of crystal grains deviating from [0001] orientation within a Zn(0002) metal anode leads to the failure of epitaxial mechanism. The electrodeposited [0001]-uniaxial oriented Zn metal anodes with a single (0002) texture fundamentally eliminate the lattice mismatch and achieve ultra-sustainable homoepitaxial growth. Using high-angle angular dark-filed scanning transmission electron microscopy, we elucidate the homoepitaxial growth of the deposited Zn following the “~ABABAB~” arrangement on the Zn(0002) metal from an atomic-level perspective. Such consistently epitaxial behavior of Zn metal retards dendrite formation and enables improved cycling, even in Zn||NH4V4O10 pouch cells, with a high capacity of 220 mAh g−1 for over 450 cycles. The insights gained from this work on the [0001]-oriented Zn metal anode and its persistently homoepitaxial mechanism pave the way for other metal electrodes with high reversibility.