钴-碳框架封装作为固态电解质层实现稳定的氧化硅负极用于锂存储  

Cobalt-carbon framework encapsulation as solid electrolyte interphase ensures stable SiO_(x)anodes for lithium storage

作　　者：陈本强 许东明 周双 常智 潘安强 Benqiang Chen;Dongmin Xu;Shuang Zhou;Zhi Chang;Anqiang Pan(School of Materials Science and Engineering,Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province,Central South University,Changsha,410083,China;School of Materials Science and Engineering,Xinjiang Environmental and Functional Materials Engineering Research Center,Xinjiang University,Urumqi,830046,China)

机构地区：[1]School of Materials Science and Engineering,Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province,Central South University,Changsha,410083,China [2]School of Materials Science and Engineering,Xinjiang Environmental and Functional Materials Engineering Research Center,Xinjiang University,Urumqi,830046,China

出　　处：《Science China Materials》2024年第5期1422-1432,共11页中国科学（材料科学）（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(51874362,22209208);Key Research and Development Program of Hunan Province(2023GK2015);the Science and Technology Innovation Leader Program of Hunan Province(2022RC3049)。

摘　　要：非化学计量的氧化硅(SiO_(x),0<x<2)是一种很有前途的锂电池负极材料.然而,它的本征电导率低,体积膨胀明显.特别是,由于连续的电解液消耗,很难形成稳定的固体电解质界面.本工作将空心氧化硅微球包裹在钴碳(Co-C)骨架及其衍生的氮掺杂碳纳米管网络(N-CNTs)中.这种设计解决了电解液消耗和SEI层重复形成的问题,并实现了快速动力学.此外,所制备材料的柔性碳纳米管和坚固金属-碳框架提供力学支撑,可以适应SiO_(x)体积变化.h-SiO_(x)@Co@N-CNTs作为锂离子电池负极材料,具有优异的循环稳定性和高倍率性能.以0.2 A g^(-1)的电流密度循环370次,容量为701 mAh g^(-1),容量保持率为100%.另外,在1.0 A g^(-1)电流密度下循环500圈,容量没有衰减.结果表明,所合成的锂离子电池结构具有一定的优越性,对材料的优化也有一定的启发作用.Non-stoichiometric silicon oxide(SiO_(x),0<x<2)is a promising anode material for lithium batteries.However,it suffers from low intrinsic conductivity and large volume expansion.In particular,reaching a stable solid electrolyte interphase(SEI)is difficult due to continuous electrolyte consumption.In this work,hollow silicon oxide(h-SiO_(x))spheres were encapsulated in cobalt-carbon(Co-C)frameworks and their derived nitrogen-doped carbon nanotube networks(N-CNTs).This design solved the problems of electrolyte depletion and repetitive formation of SEI layers and enabled fast kinetics.In addition,the flexible carbon nanotubes and metal-carbon solid frameworks of the prepared materials provide mechanical supports,which can adapt to the volume change of SiO_(x).The h-SiO_(x)@Co@N-CNTs exhibit superior cycling stability and high-rate capability as anode materials for lithium-ion batteries.It delivered a capacity of 701 mAh g^(-1)and a capacity retention of 100%over 370 cycles at a current density of 0.2 A g^(-1).In addition,the capacity did not fade after 500 cycles at a current density of 1.0 A g^(-1).The result demonstrates the advantage of the synthesized structure for lithium-ion batteries,which can also give some inspiration for this material optimization.

关 键 词：lithium-ion battery SiO_(x)anode SEI metal-organic framework volume changes 

分 类 号：O646.1[理学—物理化学] TM912[理学—化学]