Migration Energy Barriers Research Articles

Theoretical prediction of stable WB4 monolayer as a high-capacity anode material for alkali-metal ion batteries

As a rapidly evolving 2D monolayer material, tungsten tetraboride MBene exhibits innate advantages in electrochemical applications because of its unique graphene-like structure and metallic properties. In this study, we utilized first-principles calculations to identify the potential applications of WB4 as an anode material in rechargeable alkali-metal-ion batteries. The findings imply that the Li, Na, and K adsorption on the WB4 surface results in exceptionally high conductivity, and the WB4 monolayer can effectively adsorb these ions with significant adsorption energies of −2.516 eV, −2.356 eV, and −2.941 eV for Li, Na, and K ions, respectively. The results indicate that WB4 exhibits excellent stability during lithiation, sodiation, and potassiation. Notably, we propose high storage capacities for LIBs (708mAh/g), SIBs (472mAh/g), and KIBs (177 mAh/g), with maintained structural stability for the adsorption of these metal ions. The measured average open circuit voltages for WB4 were found to be 0.77 V (Li), 0.73 V (Na), and 0.80 V (K), and metallicity remain good maintained within the entire adsorption process. The calculated migration energy barriers for Li, Na, and K were 0.47 eV,0.21 eV and 0.13 eV respectively. The notable properties of WB4 make it an advantageous electrode material for alkali-metal ion batteries.

Evaluating diffusion barriers of defects in boron ion implanted diamond

The potential of diamond for electronic materials can be realized by creating well-controlled p- or n-type doping profiles. p-type doping is achieved by ion implantation of boron followed by high temperature annealing to relax the lattice, reduce the defects and create active dopant sites by allowing diffusion of defects in the diamond crystal. It has been found that even after this diffusion the percentage of active dopant sites after high temperature annealing are only a small fraction of the total doping. We perform first principles density functional theory calculations and estimate the migration barrier energy (MBE) for diffusion of carbon vacancies, hydrogen, boron and their complexes in diamond including the boron‑carbon vacancy complex which was recently observed and predicted as a color center for qubit realization. These defects are commonly found after ion implantation of boron in diamond. Here, we use nudged elastic band (NEB) technique to estimate the MBE for these defects and use it to predict the corresponding annealing temperature. Our calculations correctly predict the MBE for carbon vacancy as compared to the available references in literature and extend the calculation to other defects predicted in ion implanted diamond. Our objective of evaluating the MBE is to predict the diffusion processes occurring during post-implantation annealing of diamond.

Extending Cycling Life Beyond 300000 Cycles in Aqueous Zinc Ion Capacitors Through Additive Interface Engineering.

Developing low-cost and long-cycling-life aqueous zinc (Zn) ion capacitors (AZICs) for large-scale electrochemical energy storage still faces the challenges of dendritic Zn deposition and interfacial side reactions. Here, an interface engineering strategy utilizing a dibenzenesulfonimide (BBI) additive is employed to enhance the stability of the Zn metal anode/electrolyte interface. The first-principles calculation results demonstrate that BBI anions can be chemically adsorbed on Zn metal. Meanwhile, the experimental results confirm that the BBI-Zn interfacial layer converts the original water-richelectric double layer (EDL) into a water-poor EDL, effectively inhibiting the water related parasitic reaction at the electrode/electrolyte interface. In addition, the BBI-Zn interfacial layer introduces an additional Zn ions (Zn2+) migration energy barrier, increasing the Zn2+ de-solvation activation energy, consequently raising the Zn2+ nucleation overpotential, and thus achieving the compact and uniform Zn deposition behavior. Furthermore, the solid electrolyte interphase (SEI) layer derived from the BBI-Zn interfacial layer during cycling can further maintain the interfacial stability of the Zn anode. Owing to the above favorable features, the assembled AZIC exhibits an ultra-long cycling life of over 300000 cycles based on the additive engineering strategy, which shows application prospects in high-performance AZICs.

Plasma-induced oxygen defects in titanium dioxide to address the long-term stability of pseudocapacitive MnO2 anode for lithium ion batteries

In this work, we developed Manganese and Titanium based oxide composites with oxygen defects (MnOx@aTiOy) via plasma processing as anodes of lithium ion batteries. By appropriately adjusting the defect concentration, the ion transport kinetics and electrical conductivity of the electrodes are significantly improved, showing stable capacity retention. Furthermore, the incremental capacity is further activated and long-term stable cycling performance is achieved, with a specific capacity of 829.5 mAh/g at 1 A/g after 2000 cycles. To scrutinize the lithium migration paths and energy barriers in MnO2 and Mn2O3, the density functional theory (DFT) calculations is performed to explore the lithium migration paths and energy barriers. Although the transformation of MnO2 into Mn2O3 through oxygen defects was initially surmised to inhibit Li ions along their standard routes, our results indicate quite the contrary. In fact, the composite's lithium diffusion rate saw a substantial increase. This can be accredited to the pronounced enhancement of conductivity and ion transport efficiency in the amorphous and porous TiOy.

Defect engineering on BiFeO3 through Na and V codoping for aqueous Na-ion capacitors

Sodium with low cost and high abundance is considered as a substitute element of lithium for batteries and supercapacitors, which need the appropriate host materials to accommodate the relatively large Na+ ions. Compared to Li+ storage, Na+ storage makes higher demands on the structural optimization of perovskite bismuth ferrite (BiFeO3). We propose a novel strategy of defect engineering on BiFeO3 through Na and V codoping for high-efficiency Na+ storage, to reveal the roles of oxygen vacancies and V ions played in the enhanced electrochemical energy storage performances of Na-ion capacitors. The formation of the oxygen vacancies in the Na and V codoped BiFeO3 (denoted as NV-BFO), is promoted by Na doping and suppressed by V doping, which can be demonstrated by XPS and EPR spectra. By the first-principles calculations, the oxygen vacancies and V ions in NV-BFO are confirmed to substantially lower the Na+ migration energy barriers through the space and electric field effects, to effectively promote the Na+ transport in the crystals. Electrochemical kinetic analysis of the NV-BFO//NV-BFO capacitors indicates the dominant capacitive-controlled capacity, which depends on fast Na+ deintercalation-intercalation process in the NV-BFO electrode. The NV-BFO//NV-BFO capacitors open up a new avenue for developing high-performance Na-ion capacitors.

Strain effects on [formula omitted] anti-perovskite solid lithium-ion electrolytes: DFT study

We have systematically explored the impact of strain on various properties of Li3OX(X=Cl,Br) anti-perovskite solid lithium-ion electrolytes based on the density functional theory. The responses of bandgap, defect formation energy, Li-ion migration barrier energy and diffusivity were discussed under different strain conditions, encompassing isotropic and biaxial compressive/tensile strains ranging from −4% to 4%. Our results reveal intriguing insights: Tensile strain leads to a substantial reduction in the bandgap by up to 0.5 eV, whereas for Li3OCl/Br under compressive strain, the reduction is only ∼0.1 eV. Additionally, tensile strain facilitates the formation of Li+ vacancies and Li interstitials, thereby promoting the Li-ion diffusivity. Furthermore, the Li-ion migration barrier energy decreases when tensile strain is applied along the O–Li–O distribution direction. Analysis of AIMD results shows that tensile strain effectively enhances the diffusivity of Li ions. These findings suggest that isotropic strain strongly affects Li-ion conductivities in Li3OCl/Br anti-perovskite electrolytes, and applying tensile strain can be a potential method to enhance lithium transport.

Experimental Corroboration of Lithium Orthothioborate Superionic Conductor by Systematic Elemental Manipulation.

The Li superionic conductor Li3BS3 has been theoretically predicted as an ideal solid electrolyte (SE) due to its low Li+ migration energy barrier and high ionic conductivity. However, the experimentally synthesized Li3BS3 has a 104 times lower ionic conductivity. Herein, we investigate the effect of a series of cation and anion substitutions in Li3BS3 SE on its ionic conductivity, including Li3-xM0.05BS3 (M = Cu, Zn, Sn, P, W, x = 0.05, 0.1, 0.2, 0.25), Li3-yBS2.95X0.05 (X = O, Cl, Br, I, y = 0.05, 0.1) and Li2.75-xP0.05BS3-xClx (x = 0.05, 0.1, 0.15, 0.2, 0.4, 0.6). Amorphous ionic conductor Li2.55P0.05BS2.8Cl0.2 has a high ion conductivity of 0.52 mS cm-1 at room temperature with an activation energy of 0.41 eV. The electrochemical performance of all-solid-state batteries with Li2.55P0.05BS2.8Cl0.2 SEs show stable cycling with a discharge capacity retention of >97% after 200 cycles at 1C under 55 °C.

Dual Strategies with Anion/Cation Co-Doping and Lithium Carbonate Coating to Enhance the Electrochemical Performance of Lithium-Rich Layered Oxides.

Lithium-rich layered oxides (LLOs, Li1.2 Mn0.54 Ni0.13 Co0.13 O2 ) are widely used as cathode materials for lithium-ion batteries due to its high specific capacity, high operating voltage and low cost. However, the LLOs are faced with rapid decay of charge/discharge capacity and voltage, as well as interface side reactions, which limit its electrochemical performance. Herein, the dual strategies of sulfite/sodium ion co-doping and lithium carbonate coating were used to improve it. It founds that modified LLOs achieve 88.74 % initial coulomb efficiency, 295.3 mAh g-1 first turn discharge capacity, in addition to 216.9 mAh g-1 at 1 C, and 87.23 % capacity retention after 100 cycles. Mechanism research indicated that the excellent electrochemical performance benefits from the doping of both Na+ and SO3 2- , and it could significantly reduce the migration energy barrier of Li+ and promote Li+ migration. Meanwhile, anion and cation are co-doped greatly reduces the band gap of LLOs and increase its electrical conductivity, and its binding effect on Li+ is weakened, making it easier for Li+ to shuttle through the material. In addition, the lithium carbonate coating significantly inhibits the occurrence of interfacial side reactions of LLOs. This work provides a theoretical basis and practical guidance for the further development of LLOs with higher electrochemical performance.

Hydrogen bond interaction and mechanical property of polycarbonate polyurethane solid electrolyte

The previously unconsidered hydrogen bond (H-bond) networks in polyurethane solid polymer electrolytes (PUSPE) were studied by density functional theory. We further understood the H-bond interaction in PU, judged H-bond path, and quantified H-bond energy through atomic in molecular theory topological analysis. The frequency of the theoretical model is compared with the experimental value by Fourier transform infrared spectroscopy. The effect of H-bond on mechanical property of four kinds of polycarbonate (PCDL) PUSPE with different hard segments (diphenylmethane diisocyanate MDI/4,4′-dicycloethyl methane diisocyanate HMDI/toluene diisocyanate TDI/isoflurone diisocyanate IPDI) were discussed by double-chains models. The higher tensile strength and lower elongation at break of MDI-PUSPE result from the higher H-bond interaction strength between hard segments. The H-bond interaction between TFSI- and hard segment is studied, and it is determined by kinetic analysis that it reduces the migration energy barrier. These findings provide theoretical guidance for designing PU electrolytes in the future.

High-entropy perovskite oxides for direct solar-driven thermochemical CO2 splitting

The global energy crisis and climate change have fueled interest in solar-driven thermochemical CO2 splitting as a potential solution. However, conventional materials like CeO2 encounter limitations attributable to their low solar absorptivity and CO yield (even at high reduction temperatures), exerting a detrimental influence on both solar energy utilization and process efficiency. This study proposes high-entropy A-site doped perovskites as a potential solution for efficient solar thermochemical CO2 splitting. The increased configurational entropy enhances the solar thermal CO2 splitting cycles by decreasing oxygen vacancy formation energy and lattice oxygen migration energy barrier. This is supported by experimental results, where Sm0.25Sr0.25Ca0.25La0.25MnO3 achieved a maximum CO yield of 764.76 μmol g−1 with low temperature difference between the reduction and oxidation steps, marking an important progress in solar thermal CO2 splitting cycles. The study demonstrates the potential of high-entropy perovskites for direct solar energy harvesting with high spectrum absorption coefficients and sustainable CO2 utilization.

Spatial migration of lattice oxygen for copper-iron based oxygen carriers in chemical looping combustion

Oxygen carrier (OC) is of great importance in chemical looping combustion (CLC) technology. The migration rate of bulk lattice oxygen during reduction process is detrimental in reaction rate. However, the migration path of lattice oxygen is still not clear. In this study, a thermogravimetric analyzer (TGA) was used to investigate the reaction characteristics and kinetic parameters of the OC. The oxygen migration paths of CuO and CuFe2O4 bulk lattices were studied by density functional theory (DFT) in a five-layer (2 × 1) CuO (1 1 1) and nine-layer (1 × 1) CuFe2O4 (1 0 0) plane model. The kinetic parameters, activation energy changes and relative kinetic model of the OC reduction were explored. According to the DFT results, the deeper bulk phase oxygen requires greater more energy toovercome energy barrier for migration. CuO has a lower oxygen release capacity than CuFe2O4 in the early stages, but higher in the later stage. The reaction kinetics study revealed that the reaction mechanism of the reduction of the copper-iron composite OC is a tertiary chemical reaction control mechanism. During the reaction, the activation energy of the OC changes continuously. The macroscopic reaction kinetics agree with the microscopic simulation, proving the simulation model's validity.

Theoretical studies of C3N3Li/graphene heterostructure as a promising anode material of lithium-ion battery

The electrochemical properties of g-CN and g-CN/graphene heterostructure as anode materials for lithium-ion batteries were investigated by density functional calculations. It is shown that the Li adsorbed in the pore of g-CN has strong interactions with g-CN and a high diffusion energy barrier, leading to Li being trapped in the pores. After the pores of g-CN are fully adsorbed (C3N3Li), the migration energy barrier of Li ion on the surface of C3N3Li decreased to 0.56 eV. The calculated capacity (197 mAh/g) using C3N3Li as the host system is in agreement with experiment results. Similarly, the adsorption energy of Li in the pore of g-CN in the g-CN/graphene heterostructure is − 2.74 eV and the diffusion energy barrier (2.44 eV) for Li ion is still too high to migrate in the adjacent pores. Therefore, C3N3Li/graphene was used as the host anode system, and suitable adsorption energies (−0.81 eV), low migration energy barrier (0.43 eV), and a capacity of 694 mAh/g were obtained, which suggests that C3N3Li/graphene can be a promising anode material for Li-ion battery.

In Situ Electrochemical Tuning of MIL‐88B(V)@rGO into Amorphous V2O5@rGO as Cathode for High‐Performance Aqueous Zinc‐Ion Battery

AbstractThe design and fabrication of advanced cathode materials with excellent electrochemical properties to match the Zn anode is crucial for the development of aqueous zinc‐ion batteries (ZIBs). Herein the synthesis of MIL‐88B(V)@rGO composites is reported, in which MIL‐88B(V) nanorods are anchored on reduced graphene oxide (rGO) sheets, as cathode for ZIBs, where the graphene oxide induces the formation of small‐size nanorods instead of typical prism morphology. During the initial charge/discharge process, the cathode undergoes an in situ irreversible transformation from MIL‐88B(V) to amorphous V2O5 that acts as active site for the subsequent Zn2+ insertion/extraction. The hierarchical structure of the composites and the amorphous V2O5 provide abundant channels and active sites for Zn2+ diffusion and adsorption. The density functional theory calculation reveals that the rGO sheets have two functions, i.e., to improve the conductivity and to reduce the Zn2+ migration energy barrier. Consequently, the MIL‐88B(V)@rGO cathode exhibits an ultrahigh reversible capacity of 479.6 mAh g−1 at 50 mA g−1 and good rate performance of 263.6 mAh g−1 at 5000 mA g−1, which are superior to metal–organic frameworks (MOFs) cathodes reported in literature. This work may shed a new light to the design and fabrication of MOFs‐based cathodes for aqueous ZIBs.

Water-assisted hydrogen spillover in Pt nanoparticle-based metal–organic framework composites

Hydrogen spillover is the migration of activated hydrogen atoms from a metal particle onto the surface of catalyst support, which has made significant progress in heterogeneous catalysis. The phenomenon has been well researched on oxide supports, yet its occurrence, detection method and mechanism on non-oxide supports such as metal–organic frameworks (MOFs) remain controversial. Herein, we develop a facile strategy for efficiency enhancement of hydrogen spillover on various MOFs with the aid of water molecules. By encapsulating platinum (Pt) nanoparticles in MOF-801 for activating hydrogen and hydrogenation of C=C in the MOF ligand as activated hydrogen detector, a research platform is built with Pt@MOF-801 to measure the hydrogenation region for quantifying the efficiency and spatial extent of hydrogen spillover. A water-assisted hydrogen spillover path is found with lower migration energy barrier than the traditional spillover path via ligand. The synergy of the two paths explains a significant boost of hydrogen spillover in MOF-801 from imperceptible existence to spanning at least 100-nm-diameter region. Moreover, such strategy shows universality in different MOF and covalent organic framework materials for efficiency promotion of hydrogen spillover and improvement of catalytic activity and antitoxicity, opening up new horizons for catalyst design in porous crystalline materials.

Exploring the Relationship Between Halide Substitution, Structural Disorder, and Lithium Distribution in Lithium Argyrodites (Li6-xPS5-xBr1+x).

Lithium argyrodite superionic conductors have recently gained significant attention as potential solid electrolytes for all-solid-state batteries because of their high ionic conductivity and ease of processing. Promising aspects of these materials are the ability to introduce halides (Li6-xPS5-xHal1+x, Hal = Cl and Br) into the crystal structure, which can greatly impact the lithium distribution over the wide range of accessible sites and the structural disorder between the S2- and Hal- anion on the Wyckoff 4d site, both of which strongly influence the ionic conductivity. However, the complex relationship among halide substitution, structural disorder, and lithium distribution is not fully understood, impeding optimal material design. In this study, we investigate the effect of bromide substitution on lithium argyrodite (Li6-xPS5-xBr1+x, in the range 0.0 ≤ x ≤ 0.5) and engineer structural disorder by changing the synthesis protocol. We reveal the correlation between the lithium substructure and ionic transport using neutron diffraction, solid-state nuclear magnetic resonance (NMR) spectroscopy, and electrochemical impedance spectroscopy. We find that a higher ionic conductivity is correlated with a lower average negative charge on the 4d site, located in the center of the Li+ "cage", as a result of the partial replacement of S2- by Br-. This leads to weaker interactions within the Li+ "cage", promoting Li-ion diffusivity across the unit cell. We also identify an additional T4 Li+ site, which enables an alternative jump route (T5-T4-T5) with a lower migration energy barrier. The resulting expansion of the Li+ cages and increased connections between cages lead to a maximum ionic conductivity of 8.55 mS/cm for quenched Li5.5PS4.5Br1.5 having the highest degree of structural disorder, an 11-fold improvement compared to slow-cooled Li6PS5Br having the lowest degree of structural disorder. Thereby, this work advances the understanding of the structure-transport correlations in lithium argyrodites, specifically how structural disorder and halide substitution impact the lithium substructure and transport properties and how this can be realized effectively through the synthesis method and tuning of the composition.

Density functional theory investigation on fast storage of sodium and potassium in Ni2TeO6 as a novel promising cathode material

The limited availability of lithium metal resources has led to the development of sodium/potassium-ion batteries due to the abundance and low cost of sodium/potassium. However, finding suitable cathode materials with high capacity, stable cycling performance, and efficient electrochemical interface is still challenging. Herein, the honeycomb layered structures of P2-type A2Ni2TeO6 (A = Na, K) have been explored by density functional theory calculations as potential cathode materials for sodium and potassium storage. The optimized results show that P2-type A2Ni2TeO6 materials have large layer spacing, which enables a good reversible intercalation and results in a stable voltage platform. The calculated open-circuit voltages of Na2Ni2TeO6 and K2Ni2TeO6 are 3.69 and 3.62 V, with theoretical capacities of 138.5 and 127.9 mAh/g, respectively. The migration energy barriers of Na and K between Ni2TeO6 layers are much lower than those of other common cathode materials, making them highly promising materials for sodium and potassium storage. The thermal stabilities of intercalated Ni2TeO6 were identified through ab initio molecular dynamics simulations, lasting 10 ps at 400 K. Overall, the theoretical results of this work identified A2Ni2TeO6 as promising cathode materials for sodium and potassium storage, which could lead to the development of efficient and economically competitive sodium/potassium-ion batteries.

MnFe Prussian blue analogue-derived P3-K0.5Mn0.67Fe0.33O1.95N0.05 cathode material for high-performance potassium-ion batteries

Potassium-ion batteries (PIBs), with their high theoretical energy density and abundant natural resources, are emerging as one of the most promising candidates for next-generation energy storage systems. Nevertheless, they suffer from large volume expansion and sluggish K+ transport due to the huge ionic radius of K+, resulting in limited cyclic life and rate performance. Therefore, accelerated transport kinetics may be the key to designing electrodes with excellent potassium storage properties. Herein, we develop a new synthetic method to in-situ construct a high-efficiency PIB cathode, N-doped P3-typed K0.5Mn0.67Fe0.33O1.95N0.05 nanosheets (denoted KMFON), using the low cost Prussian blue analogue Mn2[Fe(CN)6] as a precursor. Combining experimental results and theoretical calculations, the as-synthesized KMFON exhibits large interlayer spacing, small K+ migration energy barrier, high electronic conductivity, and fast K+ transport kinetics, which are attributed to the larger-sized N substitution O. It also manifests an initial reversible capacity of 104.2 mAh g−1 at 20 mA g−1, a rate capability of 41.5 mAh g−1 at 500 mA g−1, and a high discharge capacity of 52.2 mAh g−1 after 300 cycles at 100 mA g−1. Moreover, the KMFON//pitch-derived soft carbon full cell exhibits a satisfactory rate performance of 49.4 mAh g−1 at 200 mA g−1 and a good cycling performance of 46.8 mAh g−1 after 200 cycles at 100 mA g−1, indicating the great potential of KMFON as a cathode material for PIBs.

Balancing Interfacial Reactions through Regulating p-Band Centers by an Indium Tin Oxide Protective Layer for Stable Zn Metal Anodes.

Metallic zinc (Zn) is considered as one of the most attractive anode materials for the post-lithium metal battery systems owing to the high theoretical capacity, low cost, and intrinsic safety. However, the Zn dendrites and parasitic side reaction impede its application. Herein, we propose a new principle of regulating p-band center of metal oxide protective coating to balance Zn adsorption energy and migration energy barrier for effective Zn deposition and stripping. Experimental results and theoretical calculations indicate that benefiting from the uniform zincophilic nucleation sites and fast Zn transport on indium tin oxide (ITO), highly stable and reversible Zn anode can be achieved. As a result, the I-Zn symmetrical cell achieves highly reversible Zn deposition/stripping with an extremely low overpotential of 9 mV and a superior lifespan over 4000 h. The Cu/I-Zn asymmetrical cell exhibits a long lifetime of over 4000 cycles with high average coulombic efficiency of 99.9 %. Furthermore, the assembled I-Zn/AC full cell exhibits an excellent lifetime for 70000 cycles with nearly 100 % capacity retention. This work provides a general strategy and new insight for the construction of efficient Zn anode protection layer.

Balancing Interfacial Reactions through Regulating p‐Band Centers by an Indium Tin Oxide Protective Layer for Stable Zn Metal Anodes

AbstractMetallic zinc (Zn) is considered as one of the most attractive anode materials for the post‐lithium metal battery systems owing to the high theoretical capacity, low cost, and intrinsic safety. However, the Zn dendrites and parasitic side reaction impede its application. Herein, we propose a new principle of regulating p‐band center of metal oxide protective coating to balance Zn adsorption energy and migration energy barrier for effective Zn deposition and stripping. Experimental results and theoretical calculations indicate that benefiting from the uniform zincophilic nucleation sites and fast Zn transport on indium tin oxide (ITO), highly stable and reversible Zn anode can be achieved. As a result, the I−Zn symmetrical cell achieves highly reversible Zn deposition/stripping with an extremely low overpotential of 9 mV and a superior lifespan over 4000 h. The Cu/I−Zn asymmetrical cell exhibits a long lifetime of over 4000 cycles with high average coulombic efficiency of 99.9 %. Furthermore, the assembled I−Zn/AC full cell exhibits an excellent lifetime for 70000 cycles with nearly 100 % capacity retention. This work provides a general strategy and new insight for the construction of efficient Zn anode protection layer.

High Capacity Sn Metal Anode for Aqueous Proton-Based Batteries

Aqueous proton-based batteries (APBs) as a good choice to respond battery diversity, delivering safety, cost, environmental friendliness and high-power necessary for renewable energy storage.1 However, most promising conventional aqueous battery anodes have relatively poor compatibility in acid. The limited existing anode options like Pb and MoO3 can hardly match the high-performance of advanced cathodes, leading low-voltage and unsatisfactory energy density of APBs.2-4 Therefore, the exploration of high-performance anode materials is thus of critical issue for the APB assembling.Sn metal should be one of the most suitable APB anode choices due to its relatively high hydrogen evolution reaction (HER) overpotential, large theoretical capacity (451.6 mAh g−1) and negative redox potential (−0.14 V vs. SHE). With a body-centered tetragonal crystal structure and similar facet surface energy, Sn metal deposit in polyhedral morphology isotropically. This may cause serious “dead Sn” issue when deposition capacity increases because large Sn particle has limited contact with the substrate and easily to shed from the electrode, resulting in low Coulombic efficiency and short lifespan.We will present our efforts of developing Sn anode with high capacity and long lifespan by an interfacial alloying regulation approach. Smaller grain size and more uniform Sn deposition can be achieved by higher propensity for nucleation and Sn migration energy barrier. Extra interfacial interaction suppresses shedding of Sn polyhedron particles, thus prohibiting the formation of “dead” Sn. Based on the optimized Sn metal anode, we propose several promising designs for APBs, with high performance such as high output voltages, good specific energy densities, fast kinetics, and long life. References X. Wu, J. J. Hong, W. Shin, L. Ma, T. Liu, X. Bi, Y. Yuan, Y. Qi, T. W. Surta, W. Huang, J. Neuefeind, T. Wu, P. A. Greaney, J. Lu, X. Ji. Nat. Energy 2019, 4, 123-130.W. Chen, G. Li, A. Pei, Y. Li, L. Liao, H. Wang, J. Wan, Z. Liang, G. Chen, H. Zhang, J. Wang, Y. Cui. Nat. Energy 2018, 3, 428-435.Y. Liang, Y. Jing, S. Gheytani, K. Y. Lee, P. Liu, A. Facchetti, Y. Yao. Nat. Mater. 2017, 16, 841-848.X. Wang, Y. Xie, K. Tang, C. Wang, C. Yan. Angew. Chem. Int. Ed. 2018, 57, 11569-11573.