具有微纳结构的FeS_2的制备及其储锂性能研究
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摘要：
金属硫化物具有较大的理论容量,有望成为下一代的锂电池负极材料,但是充放电过程中材料发生严重的膨胀/收缩、晶体粉化,使得材料的比容量迅速衰减.本文以铁醇盐为原料制备具有花状微纳结构的FeS_2,以达到抑制材料粉化效果.结果显示,300℃热处理得到的FeS_2样品能够充分保持中间体铁醇盐的花状微纳结构,结晶度高.450℃处理得到的样品表面为多孔状结构,而800℃处理未得到目标产物,样品分子式是Fe_9S10.电化学测试结果表明:300℃所得产物具有1 484.3mA·h/g的放电比容量,高于450℃的产物(1 326.7mA·h/g);在电流密度为200mA/g条件下,100次充放电循环后,300℃所得产物的放电比容量为480.8mA·h/g,远高于450℃所得产物的放电比容量(215.8mA·h/g).研究结果表明具有花状微纳结构对材料的粉化现象有较好的抑制作用.
Transition metal sulfide presents a big theoretical capacity,which might be one of anode materials of the next generation Li ion battery.However,its capacity would suffer a sudden decrease due to the particle powdering,as the result of the serious expansion/contraction of electrode material during the charge/discharge process.Here three samples of iron/sulfur materials were prepared by sintering the flower like micro/nano structural iron alkoxides under a mixed N2and H2S atmosphere at300,450and800℃.The results showed the sample sintered at300℃was with the structure of FeS2,which maintained the morphology of iron alkoxides precursor and showed a well crystalline.Sample obtained at450℃was also with the structure of FeS2.The surface of nanosheets within the sample exhibited a porous structure.Unfortunately,sample sintered at800℃was proved to be Fe9S10.Results of electrochemical tests showed that FeS2obtained under300℃exhibited an initial discharge capacity of1484.3mA·h/g at200mA/g,higher than that of the other samples at450℃(1326.7mA·h/g).More importantly,after100times charge/discharge cycles(200mA/g),sample prepared under300℃showed a discharge capacity of480.8mA·h/g,which was far more than the sample sintered at450℃(215.8mA·h/g).The results in this paper proved that it could be an effective way to inhibit the particle powdering by designing a flower like micro/nano structural FeS2.
作者：
李苞 李凡 代冬梅 段惠民 王新博 牛瑾 常照荣
Li Bao;Li Fan;Dai Dongmei;Duan Huimin;Wang Xinbo;Niu Jin;Chang Zhaorong(School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China)
机构地区：
betway官方app 化学化工学院
出处：
betway官方app 学报：自然科学版》 CAS 北大核心 2018年第1期64-71,共8页
基金：
国家自然科学基金(51672071 21203056) 高等学校学科创新引智计划(D17007) 河南省高校科技创新团队(17IRTSTHN001)
关键词：
花状铁醇盐 微纳结构 FeS2 锂离子电池 负极材料
flower like iron alkoxides micro nano structure FeS2 Li ion batteries anode materials
分类号：
O646 [理学—物理化学]
