摘要
Restraining the aggregation and polysulfide dissolution of edge-enriched metal sulfides is of significance for their applications as anode materials of lithium-ion batteries(LIBs)with high capacity and long cycle-life.In this work,we have reported the incorporation of MoS2 nanocrystals into amorphous carbon on the surface of reduced graphene oxide(rGO)by balancing the decomposition rates of phenolic resin(PF)-impregnated ammonium thiomolybdate(ATM),which subsequently forms the MoS2@C/rGO film through redispersion and vacuum filtration.Such structural design effectively avoids the aggregation of MoS2 nanocrystals and Li2S loss,and meanwhile ion enrichment in amorphous carbon and diffusion reinforcement can greatly accelerate the electrochemical reaction kinetics.When applied as the selfstanding anode,the MoS2@C/rGO film possesses high reversible capacities of 1164 mA h g^-1 at the current density of 0.2 A g^-1 and 810 mA h g^-1 at 6.4 A g^-1.It also exhibits quite a high capacity retention after 1000 cycles at 3.2 A g^-1.This work develops the formation theory of incorporation structures and promotes their applications in energy storage devices.
制备具有丰富边位的金属硫化物纳米晶对于提高其储锂比电容量和延长其循环寿命具有重要意义.我们通过控制酚醛树脂(PF)碳化速率以及硫代钼酸铵(ATM)分解速率之间的匹配关系,在还原石墨烯(rGO)表面成功组装了硫化钼(MoS2)纳米晶嵌入无定形碳复合材料,随后通过再分散和真空抽滤得到了MoS2@C/rGO自支撑膜.这种结构设计有效地避免了电化学反应过程中MoS2纳米晶的聚集和Li2S的流失.同时,无定形碳层促进了离子富集以及扩散加强,加快了电化学反应动力学.当MoS2@C/rGO自支撑膜作为锂离子负极时,在0.2和6.4 A g^-1的电流密度下分别表现出1164和810 mA h g^-1的可逆比电容量.在3.2 A g^-1的电流密度下经过1000次循环仍具有相当高的容量保持率.该工作为嵌入式结构材料的构筑提供了理论指导,并促进了其在储能器件中的应用.
作者
Ling Chen
Yu Liu
Zongnan Deng
Hao Jiang
Chunzhong Li
陈灵;刘宇;邓宗南;江浩;李春忠(Key Laboratory for Ultrafine Materials of Ministry of Education,School of Chemical Engineering,East China University of Science and Technology,Shanghai,200237,China;Shanghai Engineering Research Center of Hierarchical Nanomaterials,School of Materials Science and Engineering,East China University of Science and Technology,Shanghai,200237,China;School of Chemical Engineering and Technology,Sun Yat-sen University,Guangzhou,510275,China)
基金
supported by the National Natural Science Foundation of China(21975074 and 21838003)
the Basic Research Program of Shanghai(17JC1402300)
Shanghai Scientific and Technological Innovation Project(18JC1410500)
the Fundamental Research Funds for the Central Universities(222201718002)。
