基于分子筛结构的钼钒氧化物相工程在锌离子电池中的研究

Phase engineering of Mo-V oxides molecular sieves for zinc-ion batteries

随着大规模储能需求的不断增加,水性锌离子电池在世界范围内引起了越来越多的关注.然而,基于锌离子存储的宿主材料有限,严重地阻碍了锌离子电池的商业化应用.基于此,本论文精确地构建了一系列相结构(正交、三方和四方晶系)的钼钒氧化物,研究了该钼钒氧化物电极材料在锌离子电池中的储锌性能.一系列开放的框架和隧道结构有利于锌离子的扩散动力学.通过相工程优化,正交晶系的钼钒氧化物电极材料的比容量能够达到约400 m A h g^(−1),循环稳定性达到了1000次.正交晶系的钼钒氧化物相中具有大量的六元和七元环结构,在锌离子的可逆嵌入/脱出反应方面发挥了至关重要的作用.本文提出的相工程策略为锌离子电池中正极材料的设计提供了一种新方法.

With the ever-increasing demands of grid-scale energy storage,aqueous zinc-ion batteries(ZIBs)have garnered increasing attention around the world.However,limited Zn^(2+)host materials have hindered the commercialization of ZIBs.Hence,Mo-V oxides with different phase structures(orth-,tri-,and tetra-MoVO)were precisely constructed to develop phase-dependent Mo-V oxide cathodes for Zn^(2+)storage in ZIBs.The open frameworks and varied tunnel structures formed a favorable alternative for achieving suitable Zn^(2+)diffusion kinetics.With optimized phase engineering,the high specific capacity of approximately 400 mA h g^(−1) and excellent cyclic stability of 1000 cycles were achieved with orth-MoVO as the cathode.The large amount of six-and seven-member rings in the orth-MoVO phase,which allow for alternative Zn^(2+)insertion,play a vital role in hosting Zn^(2+)ions reversibly.The proposed phase engineering strategy provides a new approach toward cathode design in ZIBs.