摘要
镁离子电池由于具有高安全性、低成本等优点,近年来受到了广泛的关注.然而,镁离子缓慢的扩散动力学使其难以找到合适的具有良好电化学性能的正极材料.在此,我们设计并合成了一种新颖的柔性三维网络钒酸铁纳米片阵列/碳布(3D FeVO/CC)作为镁离子电池的无粘结剂正极材料.与原始钒酸铁纳米片(FeVO)相比,结构改善的3D无粘结剂电极能够实现全面的电化学性能优化,包括高比容量(270 mA h g^(-1))和更长的循环寿命(超过5000次循环).这种可实现的高能量密度来源于电子和离子动力学的协同优化,而循环稳定性得益于稳固的分级结构.本文采用原位X射线衍射和拉曼技术对镁离子储存过程中FeVO单相反应机理进行了研究.此外,还组装了柔性镁离子全电池(3D FeVO/CC|MgNaTi(3)O_(7)),并展示出一定的应用潜力.本工作证明了3D FeVO/CC是一种有潜力的正极材料,可以满足高性能镁离子电池的要求,也为提高镁离子电池正极材料的电化学性能开辟了一条新的途径.
Owing to their safety and low cost,magnesium ion batteries(MIBs)have attracted much attention in recent years.However,the sluggish diffusion dynamics of magnesium ions hampers the search for appropriate cathode materials with excellent electrochemical performance.Herein,we design and synthesize a novel flexible three-dimensional-networked composite of iron vanadate nanosheet arrays/carbon cloths(3 D FeVO/CC)as a binder-free cathode for MIBs.Relative to bare FeVO nanosheets,the 3 D binder-free electrode with designed architecture enables a full range of electrochemical potential,including a high specific capacity of270 mA h g^(-1) and an increased life span(over 5000 cycles).Such achievable high-density energy originates from the synergistic optimization of electron and ion kinetics,while the durability benefits from the robust structure that prevents degradation in cycling.The single-phase reaction mechanism of FeVO in the magnesium ion storage process is also explored by in-situ X-ray diffraction and Raman technologies.Moreover,a flexible MIB pouch cell(3 D FeVO/CCIMgNaTi_(3)O_(7)) is assembled and exhibits practical application potential.This work verifies that 3 D FeVO/CC is a potential candidate cathode material that can satisfy the requirements of highperformance MIBs.It also opens a new avenue to improve the electrochemical performance of cathode materials for MIBs.
作者
唐寒
左春丽
熊方宇
裴存原
谭双双
罗平
杨威
安琴友
麦立强
Han Tang;Chunli Zuo;Fangyu Xiong;Cunyuan Pei;Shuangshuang Tan;Ping Luo;Wei Yang;Qinyou An;Liqiang Mai(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,International School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Provincial Key Laboratory of Green Materials for Light Industry,Collaborative Innovation Center of Green Light-Weight Materials and Processing,School of Materials and Chemical Engineering,Hubei University of Technology,Wuhan 430070,China;Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory,Foshan 528200,China)
基金
supported by the National Key Research and Development Program of China(2020YFA0715000)
the National Natural Science Foundation of China(51832004 and 51972259)
the Natural Science Foundation of Hubei Province(2019CFA001)
Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHT2020-003)。