尖晶石型高熵氧化物的制备和电化学性能  

Synthesis and Electrochemical Performance of Spinel-type High-entropy Oxides

作　　者：项厚政 谢鸿翔 李文超 刘晓磊[2] 冒爱琴[1,2] 俞海云 XIANG Houzheng;XIE Hongxiang;LI Wenchao;LIU Xiaolei;MAO Aiqin;YU Haiyun(Key Laboratory of Metallurgical Emission Reduction&Resources Recycling,Ministry of Education;School of Materials Science and Engineering,Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials,Ministry of Education,Anhui University of Technology,Ma'anshan 243002,China)

机构地区：[1]安徽工业大学冶金减排与资源综合利用教育部重点实验室,马鞍山243002 [2]材料科学与工程学院,先进金属材料绿色制备与表面技术教育部重点实验室,马鞍山243002

出　　处：《高等学校化学学报》2020年第8期1801-1809,共9页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:51971001);冶金减排与资源综合利用教育部重点实验室(安徽工业大学)开放基金项目(批准号:JKF20-6)资助。

摘　　要：采用溶液燃烧法制备了化学组成均一的尖晶石型(Cr0.2Fe0.2Mn0.2Ni0.2M0.2)3O4(M=Co, Zn, Mg)高熵氧化物(HEOs)纳米晶粉体,并将3种高熵氧化物用作锂离子电池负极材料,研究了活性过渡金属Co和Zn阳离子与非活性Mg阳离子对电化学性能的影响.结果表明,由于具有高构型熵稳定的晶体结构, 3种高熵氧化物均表现出优异的循环稳定性,其中含有非活性Mg离子的高熵氧化物(Cr0.2Fe0.2Mn0.2Ni0.2Mg0.2)3O4不仅具有更高的初始比容量(1300 mA·h/g)和倍率性能(在3 A/g电流密度下比容量约为450 mA·h/g),且在循环500次后Li+的扩散系数为其它2种高熵氧化物的3倍以上.(Cr0.2Fe0.2Mn0.2Ni0.2Mg0.2)3O4电化学性能提高的原因是非活性Mg离子不仅避免了锂化过程中活性物质的团聚,还提高了锂离子的扩散系数.The spinel-type high-entropy oxides(HEOs),(Cr0.2Fe0.2Mn0.2Ni0.2M0.2)3O4(M = Co,Zn,and Mg)nanocrystalline powders with chemical homogeneity were synthesized by solution combustion method,and explored for the first time as anode materials for lithium-ion batteries.The effects of active transition-metal ions Co,Zn and inactive Mg ion on the structural and electrochemical performance were investigated.The results show that all the synthesized anode materials exhibit excellent cycle stability due to the entropy-stabilized crystal structure.The(Cr0.2Fe0.2Mn0.2Ni0.2Mg0.2)3O4 containing inactive Mg ion not only delivers a high initial specific capacity of 1300 mA·h/g at a specific current of 200 mA/g,but also exhibits a good rate capacity of 450 mA·h/g even at 3 A/g.Furthermore,the value of Li+diffusion coefficient of(Cr0.2Fe0.2Mn0.2Ni0.2Mg0.2)3O4 after 500 cycles is more 3 times than that of the other two high-entropy oxides.The improved electrochemical performance is attributed to the inactive Mg2+in the entropy-stabilized(Cr0.2Fe0.2Mn0.2Ni0.2Mg0.2)3O4 anode material,which not only avoids agglomeration of active materials but also increases the Li+diffusivity during the de/lithiation process.

关 键 词：锂离子电池 高熵氧化物 尖晶石型 电化学性能 非活性镁离子 

分 类 号：O646[理学—物理化学]