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The reversibility of metal anode is a fundamental challenge to the lifetime of rechargeable batteries. Though being widely employed in aqueous energy storage systems, metallic zinc suffers from dendrite formation that severely hinders its applications. Here we report texturing Zn as an effective way to address the issue of zinc dendrite. An in‐plane oriented Zn texture with preferentially exposed (002) basal plane is demonstrated via a sulfonate anion‐induced electrodeposition, noting no solid report on (002) textured Zn till now. Anion‐induced reconstruction of zinc coordination is revealed to be responsible for the texture formation. Benchmarking against its (101) textured‐counterpart by the conventional sulphate‐based electrolyte, the Zn (002) texture enables highly reversible stripping/plating at a high current density of 10 mA cm−2, showing its dendrite‐free characteristics. The Zn (002) texture‐based aqueous zinc battery exhibits excellent cycling stability. The developed anion texturing approach provides a pathway towards exploring zinc chemistry and prospering aqueous rechargeable batteries. National Research Foundation (NRF) Accepted version The authors appreciate the financial support by National Research Foundation of Singapore (NRF) investigatorship award number NRF-NRFI2017-08 (NRF2016NRF-NRFI001-22). The authors would like to acknowledge the Facility for Analysis, Characterization, Testing and Simulation, Nanyang Technological University, Singapore, for use of their electron microscopy/X-ray facilities.

To facilitate the commercialization of sodium-ion batteries (SIBs), advanced electrode materials with high sodiation capacities and enhanced cycling stabilities are essential. Herein, we investigate the effect of Fe incorporation into SnSb to generate a new ternary nanocrystalline composite based anode, which improves the cycling stability and performance of SIBs. We ensure a high-throughput synthetic approach via a rapid-solidification technique for efficient and industrially viable Fe–Sn–Sb alloy synthesis. Interestingly, the new ternary system possesses nanocrystalline domains that helped to alleviate the stresses induced upon the sodiation/desodiation reactions and thereby enhanced the performance. The Fe1.0–SnSb anode delivered a capacity of ∼500 mA h g−1 at a specific current density of 50 mA g−1 for over 120 cycles and a full-cell was designed, which could deliver one of the highest reported energy densities of ∼826 W h kganode−1. The promising electrochemical results assert the significance of microstructural engineering of alloying anodes and open up new avenues of research into rapidly solidified alloys for energy storage applications. NRF (Natl Research Foundation, S’pore) Accepted version

The increasing energy demands have prompted research on conversion and alloying materials, offering high lithium and sodium storage capacities. However, most of these materials suffer from huge volume expansion and degradation over the thousands of charging and discharging cycles required for commercial applications. In this study, we demonstrate a facile route to synthesize FeSbO4 nanocrystals that possess theoretical lithium and sodium storage capacity of 1220 mAh g–1. Operando X-ray diffraction studies reveal the electrochemically induced amorphization of the nanocrystals upon alkali-ion storage. We achieved specific storage capacities of ∼600 mAh g–1 for lithium and ∼300 mAh g–1 for sodium, respectively. The disparity in the lithium and sodium electrochemistry arises from the unique lithiation/sodiation pathways adopted by the nanocrystals. This study offers new insights into the chemistry and mechanism of conversion- and alloying-based energy storage materials that would greatly assist the development of next-generation active materials for energy storage. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version

Novel materials with high lithium-storage capacities are indispensable to substantially increase the gravimetric and volumetric energy densities of lithium-ion batteries. In this context, metal thiophosphites (MTPs) possessing a layered structure are considered ideal candidates to serve as alkali-ion hosts. Herein, the lithium storage properties of layered tin thiophosphite (SnPS3) crystals have been investigated in coin-cell configuration. The results reveal that SnPS3 undergoes a conversion and alloying reaction to deliver high lithiation capacities. The SnPS3 anode delivered a significant lithiation capacity of ∼800 mAh g-1 at a specific current of 100 mA g-1. Moreover, the layered structure was able to accommodate the volume changes upon (de)lithiation as evident from its excellent cycling stability. Additionally, the SnPS3 anode demonstrated excellent rate capability as well and delivered ∼315 mAh g-1 at a high specific current of 2 A g-1. Furthermore, the lithium-storage mechanism was investigated through cyclic voltammetry and ex situ X-ray diffraction and X-ray photoelectron spectroscopy studies. Studies of SnPS3 anode in a full cell configuration by coupling with commercial LiNi0.33Co0.33Mn0.33O2 cathode are also presented. The outstanding electrochemical performance demonstrated by the SnPS3 anode calls for further research into this novel class of metal thiophosphites for energy storage applications. National Research Foundation (NRF) Accepted version National Research Foundation of Singapore (NRF) Investigatorship award number NRF2016NRF-NRFI001-22.

Sodium-ion batteries (SIBs) have received renewed interest in recent years and are projected as an alternative to the existing lithium-ion battery (LIB) system. Research on SIBs is impelled by the low cost and abundant supply of sodium resources, the similar electrochemistry of SIBs and LIBs and the competing electrochemical performance achieved in recent years. Significant progress has been made in the development of alloying anodes for SIBs which offer high gravimetric and volumetric energy densities when compared to the conventional intercalation based anodes. Recent progress in the field of advanced operando and ex situ characterization techniques as well as theoretical computational studies has shed light on the sodiation mechanism of these alloying anodes. Herein, we review the recent developments in alloying anodes for SIBs. Primarily Sn, Sb, and P based alloying anodes are focused on and the progress in Bi, Ge and Si is also discussed. We focus on the sodiation mechanism of these alloying anodes, recently revealed by means of advanced experimental and computational tools, to enable the design of efficient strategies for enhanced electrochemical performance. We also discuss synthetic methodologies and novel approaches adopted for alloying anodes to mitigate the challenges faced during the (de)sodiation cycles. The future outlook and issues to be addressed to realize the practical implementation of alloying anodes are also discussed. NRF (Natl Research Foundation, S’pore) Accepted version

Owing to the high theoretical sodiation capacities, intermetallic alloy anodes have attracted considerable interest as electrodes for next-generation sodium-ion batteries (SIBs). Here, we demonstrate the fabrication of intermetallic Fe–Sb alloy anode for SIBs via a high-throughput and industrially viable melt-spinning process. The earth-abundant and low-cost Fe–Sb-based alloy anode exhibits excellent cycling stability with nearly 466 mAh g–1 sodiation capacity at a specific current of 50 mA g–1 with 95% capacity retention after 80 cycles. Moreover, the alloy anode displayed outstanding rate performance with ∼300 mAh g–1 sodiation capacity at 1 A g–1. The crystalline features of the melt-spun fibers aid in the exceptional electrochemical performance of the alloy anode. Further, the feasibility of the alloy anode for real-life applications was demonstrated in a sodium-ion full-cell configuration which could deliver a sodiation capacity of over 300 mAh g–1 (based on anode) at 50 mA g–1 with more than 99% Coulombic efficiency. The results further exhort the prospects of melt-spun alloy anodes to realize fully functional sodium-ion batteries. Accepted version