摘要
通过对氧化石墨烯(GO)进行微观调控处理得到少层GO。采用喷雾干燥再高温改性的方法制备LiFePO_4/石墨烯锂离子电池复合正极材料;GO还原后即可得到石墨烯,其优良的导电性可以提高LiFePO_4的电子传输能力。通过X射线衍射(XRD)、红外光谱(FTIR)、扫描电镜(SEM)、透射电镜(TEM)和电化学测试技术等方法对复合材料的结构、形貌及电化学性能进行表征。石墨烯的复合使材料颗粒间构建空间三维导电网络,提高了电解质/电极材料界面的电荷转移速率,改善了LiFePO_4的电化学性能。电化学测试结果表明,在0.1C时LiFePO_4的放电比容量为155mAh/g,LiFePO_4/石墨烯复合材料的放电比容量为164mAh/g;1C和2C倍率时,LiFePO_4/石墨烯复合材料的放电比容量分别为140,119mAh/g。
Micro layer of GO was obtained by micro adjustment and control.LiFePO4/graphene com-posite cathode materials were synthesized using a spray drying followed by high temperature reduction modification method,to improve conductivity of LiFePO4 with excellent conductivity of graphene.The structure,morphology and electrochemical performance of the composite materials were charac-terized by XRD,FTIR,SEM,TEM and electrochemical measurement technologies.The three-di-mensional conductive network was constructed by graphene composite in material particles,which can improve the charge transfer rate of the interface of electrolyte/electrode materials and the electrochem-ical performance of LiFePO4.The results show that the discharge specific capacity of LiFePO4 without graphene is only 155mAh/g,while the discharge specific capacity of LiFePO4/graphene is 164mAh/g at 0.1C.The discharge specific capacity of LiFePO4/graphene is 140,119mAh/g at 1,2C,respectively.
作者
邓凌峰
覃昱焜
彭辉艳
连晓辉
吴义强
DENG Ling-feng;QIN Yu-kun;PENG Hui-yan;LIAN Xiao-hui;WU Yi-qiang(School of Materials Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2018年第2期9-15,共7页
Journal of Materials Engineering
基金
国家自然科学基金重点资助项目(31530009)
关键词
氧化石墨烯
石墨烯
喷雾干燥
导电网络
电化学性能
graphene oxide(GO)
graphene
spray drying
conductive network
electrochemical perform
