多孔硅@石墨烯-碳纳米管的制备及性能研究  

Preparation and lithium-storage performance of porous silicon@graphene-carbon-nanotubes

作　　者：尚志同 戴儇 刘彬 喻强 李小成 SHANG Zhitong;DAI Xuan;LIU Bin;YU Qiang;LI Xiaocheng(Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou Jiangxi 341000,China;Jiangxi Key Laboratory of Power Battery and Materials,Ganzhou Jiangxi 341000,China;Shanghai Marine Equipment Research Institute,Shanghai 200031,China)

机构地区：[1]江西理工大学材料冶金化学学部,江西赣州341000 [2]江西省动力电池及材料重点实验室,江西赣州341000 [3]上海船舶设备研究所,上海200031

出　　处：《电源技术》2021年第12期1533-1536,1557,共5页Chinese Journal of Power Sources

基　　金：国家自然科学基金(51862013);江西省自然科学基金(20202ACBL204014,20202BABL204018)。

摘　　要：硅以其较高的理论比容量、较低的脱锂电位成为最具应用潜力的负极材料。为解决硅在锂化过程中高达300%的体积膨胀和导电性差的问题,以Al-Si合金为原料,通过选择性酸刻蚀工艺得到多孔硅微球(p-Si),并通过静电自组装法在其表面包覆石墨烯(p-Si@G),以Fe_(2)O_(3)-Al_(2)O_(3)为催化剂,采用化学气相沉积法制备了p-Si@G-CNTs复合材料,并系统研究了石墨烯包覆和碳纳米管的生长对于p-Si电化学性能的提升作用和提升机制。结果表明:在p-Si表面包覆石墨烯后其循环稳定性和首次库仑效率得到大幅改善。通过进一步在p-Si@G生长碳纳米管后其倍率性能得到明显改善。当p-Si@G与催化剂质量比为5∶1时,所制备的p-Si@G-CNTs性能最佳,在0.5 A/g电流密度下循环100次后比容量可以达到1410.9 mAh/g。同时,该材料也展现出了优异的倍率性能,在8 A/g电流密度下仍然有536.2 mAh/g的比容量,具有良好的应用前景。Due to its high theoretical specific capacity and low lithiation/delithiation potential,silicon is considered as the most potential anode materials for lithium-ion battery(LIBs).Porous silicon microspheres(p-Si)were obtained by selective acid etching of Al-Si alloy,then graphene was coated on the surface of p-Si microspheres by an electrostatic self-assembly strategy.With the resulting p-Si@G as substrate and Fe_(2)O_(3)-Al_(2)O_(3) as catalyst,carbon nanotubes(CNTs)were successfully grown on the surface of p-Si@G through a chemical vapor deposition method.The electrochemical performance of graphene and CNTs on p-Si were systematically evaluated.The results suggest that,when the ratio of p-Si@G to catalyst reaches 5:1,the p-Si@G-CNT composite demonstrates the best electro-chemical performance,and delivers a high specific capacity of 1410.9 mAh/g after 100 cycles at current density of 0.5 A/g.Meanwhile,the p-Si@G-CNTs also exhibits excellent rate performance and has a specific capacity of 536.2 mAh/g at a high current density of 8 A/g,suggesting its promising application in lithium-ion battery.

关 键 词：多孔硅微球 静电自组装法 石墨烯 化学气相沉积法 碳纳米管 

分 类 号：TM912.9[电气工程—电力电子与电力传动]