De Luna Yannis, Mohamed Zakiah, Dawoud Abdulilah, Bensalah Nasr
Materials Science and Technology Graduate Program, Department of Physics and Materials Science, Qatar University Doha 2713 Qatar.
Faculty of Applied Science, Universiti Teknologi MARA 40450 Shah Alam Selangor Malaysia.
RSC Adv. 2024 Dec 11;14(53):39193-39203. doi: 10.1039/d4ra06871h. eCollection 2024 Dec 10.
Vanadium oxide-based compounds have attracted significant interest as battery materials, especially in aqueous Zn-ion batteries, due to favorable properties and compatibility in Zn-ion systems. In a simple hydrothermal method with moderate conditions, a novel vanadium oxide compound has been synthesized using ammonium metavanadate with oxalic acid as a reducing agent. Various characterization techniques confirmed the formation of layered VO(HO) nanoplatelets with a tetragonal crystal structure. The as-prepared cathode material was tested in coin cells against a Zn metal anode in two aqueous electrolytes of the same concentration: ZnSO·7HO and Zn(CFSO). Electrochemical results showed high reversibility of Zn insertion/de-insertion and impressive cycling stability with aqueous Zn(CFSO) electrolyte. Notably, the cathode material delivered a specific capacity of 150 mA h g at 100 mA g and a relatively constant coulombic efficiency near 100%, indicating impressive stability during cycling and reversibility of charge/discharge electrochemical reactions. Post-mortem characterization exposed a significant structural change in the as-prepared cathode material from nanoplatelets to nanoflakes after full discharge, which reverted to nanoplatelets after charging, reflecting the high level of reversibility of the material. DFT calculations revealed a structural change in the material after cycling, providing mechanistic insights in Zn-ion storage.
基于氧化钒的化合物作为电池材料引起了广泛关注，特别是在水系锌离子电池中，因为它们在锌离子体系中具有良好的性能和兼容性。在一种条件温和的简单水热法中，以偏钒酸铵和草酸作为还原剂合成了一种新型氧化钒化合物。各种表征技术证实形成了具有四方晶体结构的层状VO(HO)纳米片。将制备好的阴极材料在硬币电池中与锌金属阳极在两种相同浓度的水系电解质中进行测试：ZnSO·7HO和Zn(CFSO)。电化学结果表明，在水系Zn(CFSO)电解质中，锌的嵌入/脱出具有高可逆性，并且具有令人印象深刻的循环稳定性。值得注意的是，阴极材料在100 mA g的电流密度下具有150 mA h g的比容量，并且库仑效率在100%附近相对恒定，这表明在循环过程中具有令人印象深刻的稳定性以及充放电电化学反应的可逆性。充放电后表征显示，制备好的阴极材料在完全放电后从纳米片显著转变为纳米薄片，充电后又恢复为纳米片，这反映了该材料的高可逆性。密度泛函理论（DFT）计算揭示了循环后材料的结构变化，为锌离子存储提供了机理见解。
