阴离子掺杂Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)的制备及储锂性能  

Preparation of Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)Doped by Anions and Its Lithium Storage Property

作　　者：邱天培 汪椰吉 杨格格 黄俊杰[1] QIU Tianpei;WANG Yeji;YANG Gege;HUANG Junjie(School of Chemistry and Chemical Engineering,Shaoxing University,Shaoxing,Zhejiang 312000)

机构地区：[1]绍兴文理学院化学化工学院,浙江绍兴312000

出　　处：《绍兴文理学院学报》2023年第2期67-73,共7页Journal of Shaoxing University

基　　金：国家自然科学基金项目“钴(镍)基MOFs材料设计制备及其阴离子嵌脱机理”(21875142).

摘　　要：层状富锂锰基氧化物在首次放电过程中晶格结构会发生相转化而引发晶格氧的不可逆损失,导致其低的首圈库伦效率(ICE)以及差的循环稳定性.减少表面活性氧(O^(2-))来抑制不可逆氧气的析出是提高该类材料电化学性能的关键.基于HSAB软硬酸碱理论,分别以FCl,FBr、FI三种不同的阴离子组合对Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)材料进行协同掺杂.得益于更稳定的反应界面,掺杂后的材料在充放电过程中的相转变得到了抑制,减少了不可逆氧的释放,基于此,阴离子掺杂材料的ICE从73.4%提高到了81.5%.此外,F-离子更强的相互作用抑制了过渡金属向Li位的迁移,从而提升了其循环稳定性.During the first discharge process,the phase transformation which occurred in the lattice structure of layered Lithium-rich Manganese-based Oxides could triggle off an irreversible loss of lattice oxygen,thereby causing the low initial coulombic efficiency(ICE)and poor cycle stability.The inhibition of irreversible Oxygen evolution is the key to improving the electrochemical performance of this material by reducing surface reactive oxygen(O^(2-)).According to Hard-Soft-Acid-Base(HSAB),Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)is prepared by co-doped with corresponding three anions groups of FCl,FBr and FI.More stable reaction interface contributes to restriction of phase transformation,and irreversible oxygen release is reduced.On this basis,ICE of the anions doped material is increased from 73.4%to 81.5%.In addition,the stronger interaction of F-with transition metal ions produce less possibility about transfer of transition metal ions to lithium location,thus the cycle stability has improved.

关 键 词：富锂锰基氧化物 阴离子掺杂 电化学性能 

分 类 号：TQ127[化学工程—无机化工]