摘要
氟化亚铁(FeF2)因较高的理论比容量和充放电电势而成为高能量密度锂电正极材料的优选,但其导电性差、电化学过程中体积变化等因素阻碍了其实际应用。本文以二茂铁和氟化铵作为前驱体,采用高温热反应法合成了碳层包覆氟化亚铁(FeF2@C)球形核壳纳米复合结构,并结合XRD、SEM-EDS、TG对样品的物相、形貌和结构进行表征,考察了样品在1.3V-4.2V之间,电流密度为30mA g-1下的循环充放电性能。实验结果表明:较高的初始比容量和良好的循环性能归因于外包覆碳层促进了充放电过程中的电子导电性,并限制了转化过程中的体积变化。
Iron(II)fluoride(FeF2)is a preferred cathode material for lithium-ion batteries of high energy density due to its high theoretical specific capacity and high potential.Its practical application is hindered by the poor conductivity and volume expansion during the discharge-charge process.In this work,core-shell spherical nanostructures with FeF2 as core and carbon as shell(FeF2@C)were synthesized by thermal pyrolysis,using ferrocene and NH4F as precursors.XRD,SEM-EDS,and TG were used to characterize the phase,morphology,and structure of the FeF2@C structure.The electrochemical properties of FeF2@C were measured at a current density of 30 mA g-1 between a voltage range of 1.3 V-4.2 V.The high initial discharge capacity and good cycling performance are attributed to two reasons:the good conductivity of the carbon shell promoting the electronic transport of FeF2;carbon shell’s buffering the volume change during the conversion reaction of FeF2.
作者
张艳丽
张强
王晶鑫
谢乐琼
王莉
谢英鹏
郝永胜
何向明
ZHANG Yan-li;ZHANG Qiang;WANG Jing-xin;XIE Le-qiong;WANG Li;XIE Ying-peng;HAO Yong-sheng;HE Xiang-ming(School of Materials Science and Engineering,Shenyang University of Chemical Technology,Shenyang,Liaoning Province,110142,China;Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing,100084,China)
出处
《电池工业》
CAS
2021年第3期126-130,共5页
Chinese Battery Industry
基金
科技部国际合作项目(2019YFE010200)
辽宁省自然科学基金指导计划(20180551021,20180550832,2019-ZD-0081)
辽宁省高等学校创新人才支持计划(LR2018074)
辽宁省教育厅基础研究项目(LJ2020006)
