Sequential phosphorization and carbonization with modulated d-p orbital interactions in cobalt phosphides for enhanced polysulfide redox kinetics  

作　　者：Chenshan Lv Zhi Zheng Liangtao Yang Hailiang Cao Peng Li Yanqin Miao Wei Deng Yuan Chen 

机构地区：[1]Key Laboratory of Interface Science and Engineering in Advanced Materials,Ministry of Education,College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China [2]School of Chemical and Biomolecular Engineering,The University of Sydney,Darlington,New South Wales 2006,Australia [3]Shenzhen Institute of Advanced Technology,Chinese Academy of Sciences,Shenzhen 518055,Guangdong,China [4]School of Science,RMIT University,Melbourne,Victoria 3000,Australia

出　　处：《Journal of Energy Chemistry》2025年第3期576-585,共10页能源化学(英文版)

基　　金：support from the National Natural Science Foundation of China(U21A20174);the Fundamental Research Program of Shanxi Province(202203021221049);the Science and Technology Innovation Talent Team Project of Shanxi Province(202304051001010);support from the Shenzhen Science and Technology Program(RCBS20221008093340100);support from the Australian Research Council(ARC)Discovery Early Career Researcher Award(DE230101068);support from the ARC Research Hub for Safe and Reliable Energy(IH200100035)。

摘　　要：Cobalt phosphides are potential catalysts to assist the conversion of lithium polysulfides(LiPSs)in lithium-sulfur(Li-S)batteries.However,existing synthesis methods have difficulty precisely tuning their band valences,which is crucial to balancing intermediate products'adsorption and conversion abilities in Li-S batteries.Moreover,studies on the relationship between their band structures and electrochemical performance are limited.Herein,we report cobalt phosphides(Co_(x)P)with a heterogeneous interface of CoP/Co2P embedded in hollow carbon nanofibers(denoted as Co_(x)P@HCNF)via a one-step sequential phosphorization and carbonization strategy,which is applied as an effective interlayer for Li-S batteries.The Co band valence in CoxP was adjusted to regulate the d-p band gap.Theoretical calculations predict that Co_(x)P with a narrowed d-p band center can optimize the electron transfer kinetics and the adsorption affinity with LiPSs.Li-S full cells with a Co_(x)P@HCNF interlayer demonstrated a high specific capacity of1265 mA h g^(-1)at 0.2C and excellent cycle stability of 788 mA h g^(-1)over 400 cycles at 2.0C.A cell with a lean electrolyte(6.0μL mg^(-1))and a high sulfur loading(6.2 mg cm^(-2))delivered a high areal capacity of4.5 mA h cm^(-2)at 0.5C.This study demonstrates that bimetallic coupling-induced electronic-state modulation effectively balances the chemical adsorption and catalytic capability for developing high-performance Li-S batteries.

关 键 词：Lithium-sulfur battery Cobalt phosphide Heterogeneous structures INTERLAYER 

分 类 号：TM912[电气工程—电力电子与电力传动]