氧硫双掺杂CNTs水系导电剂辅助构筑高性能石墨/SiO负极  

O,S co-doped carbon nanotube aqueous conductive additive assisted construction of high-performance graphite/SiO anode

作　　者：马桂璇 徐子桐 肖志华 宁国庆 魏强[1] 徐春明[1,3] MA Guixuan;XU Zitong;XIAO Zhihua;Ning Guoqing;WEI Qiang;XU Chunming(State Key Laboratory of Heavy Oil,China University of Petroleum(Beijing),Beijing 102249,China;Department of Chemical and Biological Engineering,University of Ottawa,Ottawa K1N 6N5,Ontario,Canada;College of Carbon Neutrality Future Technology,China University of Petroleum(Beijing),Beijing 102249,China;Jiangsu Cnano Technology Company Limited,Zhenjiang 212001,Jiangsu,China)

机构地区：[1]中国石油大学(北京)重质油全国重点实验室,北京102249 [2]渥太华大学化学与生物工程系,渥太华K1N 6N5 [3]中国石油大学(北京)碳中和未来技术学院,北京102249 [4]江苏天奈科技股份有限公司,江苏镇江212001

出　　处：《化工进展》2024年第S01期443-456,共14页Chemical Industry and Engineering Progress

基　　金：中国石油大学(北京)校青年拔尖人才科研启动基金(ZX20230047);国家自然科学基金(21706283)。

摘　　要：由于石墨具有资源丰富、比容量高和嵌锂电位低等优势,被视为重要的商业化锂离子电池(LIBs)负极材料。然而,石墨较低的理论比容量限制了LIBs能量密度的进一步提升。因此,本文将少量的氧化亚硅(SiO)添加到石墨中,再分散到少量的氧硫掺杂双壁碳纳米管(O,S-DCNTs)水系导电剂中,得到石墨/SiO复合负极。其中,O,S-DCNTs是通过将双壁碳纳米管(DCNTs)在空气中预氧化处理,再通过浸渍法与MgSO4混合后煅烧所得的,具有纳米孔结构丰富、硫含量高和亲水性强等特性。通过电池性能测试发现,引入O,S-DCNTs后石墨/SiO复合负极的比容量、倍率和循环性能得到显著提升。此外,其循环性能是纯硫掺杂碳纳米管(S-DCNTs)石墨/SiO负极的4倍,这主要归因于高分散的O,S-DCNTs能够构筑大量的导电网络,提供丰富的锂离子存储空间和活性位点,解决SiO导电性差和体积膨胀系数大问题,从而显著提高石墨负极的电化学性能。本文为高性能负极材料的制备与储能应用提供了新的思路和方向。Due to graphite's advantages such as abundant resources,high specific capacity and low lithium intercalation voltage,it is considered an important commercial anode for lithium-ion batteries(LIBs).However,the lower theoretical specific capacity of graphite limits further improvement in the energy density of LIBs.Therefore,in this study,a graphite/SiO composite anode was obtained by adding a small amount of silicon oxide(SiO)to graphite,which was then dispersed into a small amount of O,S codoped double-walled carbon nanotube(O,S-DCNTs)aqueous conductive additive.The O,S-DCNTs were prepared by pre-oxidizing double-walled carbon nanotubes(DCNTs)in air and then mixing and calcining them with MgSO_(4),possessing abundant nanoscale pore structures,high sulfur content and strong hydrophilicity.Battery performance tests revealed that the introduction of O,S-DCNTs significantly improved the specific capacity,rate capability and cycling stability of the graphite/SiO composite anodes.Additionally,its cycling stability was four times that of graphite/SiO anodes containing pure sulfur-doped carbon nanotubes(S-DCNTs).This improvement was mainly attributed to the highly dispersed O,S-DCNTs,which can construct numerous conductive networks,provide abundant Li+storage space and active sites,and address the issues of poor conductivity and large volume expansion coefficient of SiO,thereby significantly enhancing the electrochemical performance of the graphite anode.This work provided new insights and directions for the preparation and energy storage applications of highperformance anode materials.

关 键 词：双壁碳纳米管 氧化亚硅 石墨负极 水系导电剂 储能 纳米材料 复合材料 电化学 

分 类 号：TQ152[化学工程—电化学工业]