Sun Rui, Dong Siyang, Xu Feng, Li Zhiyong, Wang Caihong, Lu Shengjun, Fan Haosen
College of Materials Science and Metallurgy Engineering, Guizhou University, Guiyang 550025, PR China.
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.
Dalton Trans. 2022 May 17;51(19):7607-7612. doi: 10.1039/d2dt00665k.
Recently, aqueous zinc-ion batteries have become a hot research topic in the field of grid-scale application, which can be attributed to their low-cost, aqueous electrolyte and dominant theoretical reversible capacity. Nevertheless, the lack of suitable cathode materials greatly hinders the development of aqueous zinc-ion batteries. In this work, we adopt a simple one-step synthesis strategy to prepare (NH)VO with an intercalation of Na and HO, which exhibits a novel crystal structure in which the ammonium ion, crystal water, and sodium ion co-locate in the VO layers. The co-intercalation not only effectively enhances the binding energy between V-O layers to suppress vanadium dissolution but also successfully improves the structural stability to alleviate the structural collapse during the cyclic process. As result, (NH)VO with the intercalation of crystal water and Na presents a remarkable reversible discharge capacity of 423.9 mA h g after 90 cycles at 0.1 A g with an excellent energy density of 350.3 W h kg and demonstrates an outstanding specific capacity of 182.5 mA h g at the high current density of 5 A g upon 1400 cycles during the ultra-wide voltage window of 0.1-2.0 V.
最近，水系锌离子电池已成为电网规模应用领域的一个热门研究课题，这归因于其低成本、水系电解质和占主导地位的理论可逆容量。然而，缺乏合适的阴极材料极大地阻碍了水系锌离子电池的发展。在这项工作中，我们采用一种简单的一步合成策略来制备嵌入Na和H₂O的(NH₄)₃V₂(PO₄)₃，其呈现出一种新颖的晶体结构，其中铵离子、结晶水和钠离子共位于V-O层中。这种共嵌入不仅有效地增强了V-O层之间的结合能以抑制钒溶解，而且成功地提高了结构稳定性以减轻循环过程中的结构坍塌。结果，嵌入结晶水和Na的(NH₄)₃V₂(PO₄)₃在0.1 A g下循环90次后呈现出423.9 mA h g的显著可逆放电容量，具有350.3 W h kg的优异能量密度，并且在0.1-2.0 V的超宽电压窗口下，在5 A g的高电流密度下经过1400次循环后表现出182.5 mA h g的出色比容量。
