S-doped mesoporous graphene modified separator for high performance lithium-sulfur batteries  

作　　者：Xinlong Ma Chenggen Xu Yin Yang Dong Sun Kai Zhao Changbo Lu Peng Jin Yiting Chong Sirawit Pruksawan Zhihua Xiao Fuke Wang 

机构地区：[1]State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing,Changping,102249,China [2]State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization,China Pingmei Shenma Group,Pingdingshan 467000,China [3]Institute of Materials Research and Engineering(IMRE),Agency for Science,Technology and Research(A*STAR),2 Fusionopolis Way,Innovis#08-03,138634,Republic of Singapore

出　　处：《Materials Reports(Energy)》2024年第3期60-68,共9页材料导报（能源）（英文）

基　　金：supported by the Science Foundation of China University of Petroleum,Beijing(No.ZX20230047);Open Research Fund of State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization,China Pingmei Shenma Group(No.41040220201308).

摘　　要：Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,the practical application of LSB is seriously hampered by its short cycle life and high self-charge owing to the apparent shuttle effect of soluble lithium polysulfides.Using MgSO_(4)@MgO composite as both template and dopant,template-guided S-doped mesoporous graphene(SMG)is prepared via the fluidized-bed chemical vapor deposition method.As the polypropylene(PP)modifier,SMG with high specific surface area,abundant mesoporous structures and moderate S doping content offers a wealth of physical and chemical adsorptive sites and reduced interfacial contact resistance,thereby restraining the serious shuttle effects of lithium polysulfides.Consequently,the LSB configured with mesoporous graphene(MG)as S host material and SMG as a separator modifier exhibits an enhanced electrochemical performance with a high average capacity of 955.64 mA h g^(-1) at 1C and a small capacity decay rate of 0.109%per cycle.Additionally,the density functional theory(DFT)calculation models have been rationally constructed and demonstrated that the doped S atoms in SMG possess higher binding energy to lithium polysulfides than that in MG,indicating that the SMG/PP separator can effectively capture soluble lithium polysulfides via chemical binding forces.This work would provide valuable insight into developing a versatile carbon-based separator modifier for LSB.

关 键 词：Fluidized-bed chemical vapor deposition Mesoporous graphene S doping Separator modification Lithium-sulfur battery 

分 类 号：O61[理学—无机化学]