氮掺杂Co/Co_(3)O_(4)@C核壳纳米粒子作为锂电池负极材料的性能  

N-doped Co/Co_(3)O_(4)@C core-shell nanoparticles as anode materials for lithium-ion batteries

作　　者：魏素凤 平昕 李春霖 王国勇[2] WEI Su-feng;PING Xin;LI Chun-lin;WANG Guo-yong(College of Materials Science and Engineering,Changchun University of Technology,Changchun 130012,China;Collegeof Materials Science and Engineering,Jilin University,Changchun 130022,China)

机构地区：[1]长春工业大学材料科学与工程学院,长春130012 [2]吉林大学材料科学与工程学院,长春130022

出　　处：《吉林大学学报（工学版）》2023年第2期376-384,共9页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金重点研发项目(2018YFA0702304);长春市重点研发项目(3A4185522416)。

摘　　要：高容量的过渡金属氧化物要想替代目前低容量的商业碳作为锂离子电池负极材料,必须设计解决碎化问题和电导率问题。本文通过热解和水热氧化法合成了N掺杂的碳基Co/Co_(3)O_(4)@C纳米粒子核壳结构复合材料。通过调整水热时间,可以获得结构完整、形态规则、尺寸均匀的产品。其作为锂离子电池电极材料,在0.1A/g恒流循环50次后,放电容量稳定在620 mA·h/g(碳质量分数为56.8%),高于其理论比容量,在2A/g恒流下250次循环后,可逆容量为572 mA·h/g,库仑效率可保持在99.8%左右。这说明具有良好分散性的N掺杂碳基Co/Co_(3)O_(4)@C纳米粒子核壳结构具有优良的结构稳定性和电导率,作为负极材料有希望应用于高容量、大功率的锂离子电池当中。When high-capacity transition metal oxides want to replace current low-capacity commercial carbon as anode materials for lithium-ion batteries,they must be designed to solve the pulverization and conductivity issues.In this paper,N-doped carbon-based Co/Co_(3)O_(4)@C core-shell structure composites by pyrolysis and hydrothermal oxidation were innovatively synthesized by us.By adjusting the hydrothermal time,complete structure,regular morphology and uniform size product can be achieved.The core-shell structure composed of nitrogen-doped carbon can shorten the transmission path of lithium-ion,which leads to the high conductivity of these composites.In addition,there are more pores in the amorphous carbon,which can not only make full contact with the electrolyte during charging and discharging,but also reduce the volume expansion generated in the cycling process and delay the rate of capacity decay caused by the structural collapse.The results of the electrochemical show that the discharge capacity was stable at 620mA·h/g (carbon content 56.8 wt%) after 50 cycles of constant current of 0.1 A/g,which is higher than its theoretical specific capacity.After 250 cycles,the reversible capacity can reach 572 mA·h/g and the coulomb efficiency can be maintained at about 99.8%under the constant current of 2A/g.The results show that the N-doped carbon-based Co/Co_(3)O_(4)nanoparticle core-shell structure composites with good dispersion can improve the conductivity and electrochemical performance of the electrode of the high capacity of lithium ion batteries with a long cycle life.

关 键 词：金属有机骨架 核壳结构 锂离子电池 负极材料 

分 类 号：TB332[一般工业技术—材料科学与工程]