Quantitative defect regulation of heterostructures for sulfur catalysis toward fast and long lifespan lithium-sulfur batteries  

作　　者：Saisai Qiu Xinqi Liang Shuwen Niu Qingguo Chen Gongming Wang Minghua Chen 

机构地区：[1]Key Laboratory of Engineering Dielectric and Applications(Ministry of Education),School of Electrical and Electronic Engineering,Harbin University of Science and Technology,Harbin 150080,China [2]Hefei National Laboratory for Physical Science at the Microscale,Department of Chemistry,University of Science&Technology of China,Hefei 230026,China

出　　处：《Nano Research》2022年第9期7925-7932,共8页纳米研究（英文版）

基　　金：the National Natural Science Foundation of China(No.52122702);the Natural Science Foundation of Heilongjiang Province of China(No.JQ2021E005);the Fundamental Research Foundation for Universities of Heilongjiang Province(No.LGYC2018JQ006).

摘　　要：The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosheets and porous nitrogen-doped carbon(Bi_(2)Se_(3−x)/NC)is prepared by selenizing bismuth metal-organic frameworks as a multifunctional sulfur host.The highly efficient immobilization-conversion on LiPSs is realized by the synergistic effect of structure construction strategy and defect engineering.It is found that Bi_(2)Se_(3−x)with the suitable amount of selenium vacancies achieves the best electrochemical performance due to the advantages of its structure and composition.These results confirm the intrinsic correlation between defects and catalysis,which are revealed by computational and experimental studies.Due to these superiorities,the developed sulfur electrodes exhibited admirable stability and a fairly lower capacity decay rate of approximately 0.0278%per cycle over 1,000 cycles at a 3 C rate.Even at the high sulfur loading of 6.2 mg·cm^(−2),the cathode still demonstrates a high discharge capacity of 455 mAh·g^(−1)at 1 C.This work may enlighten the development of mechanism investigation and design principles regarding sulfur catalysis toward high-performance Li-S batteries.

关 键 词：lithium-sulfur(Li-S)batteries lithium polysulfides(LiPSs) shuttle effect redox kinetics selenium vacancy sulfur catalysis 

分 类 号：TM912[电气工程—电力电子与电力传动]