硅/还原氧化石墨烯纳米复合材料的制备及储锂性能  

Preparation and Lithium Storage Properties of Silicon/Reduced Graphene Oxide Nanocomposites

作　　者：王鸣[1,2] 曾永浩 何跃 方鹏飞 王晓亮 沈丁[1,2] WANG Ming;ZENG Yonghao;HE Yue;FANG Pengfei;WANG Xiaoliang;SHEN Ding(School of Materials Science and Engineering,Liaoning Technical University,Fuxin 123000,Liaoning,China;Key Laboratory of Mineral High Value Conversion and Energy Storage Materials of Liaoning Province,Fuxin 123000,Liaoning,China)

机构地区：[1]辽宁工程技术大学材料科学与工程学院,辽宁阜新123000 [2]辽宁省矿物高值化与储能材料重点实验室,辽宁阜新123000

出　　处：《硅酸盐学报》2023年第7期1689-1696,共8页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金项目(51974152,51874167);辽宁省中央引导地方科技发展基金项目(2022JH6/100100047);辽宁省教育厅科学研究面上项目(LJKZ0363);辽宁工程技术大学学科创新团队项目(LNTU20TD-09,LNTU20TD-16)。

摘　　要：以商业纳米Si颗粒(60 nm)和天然鳞片石墨为原料,采用静电原位自组装和水热还原的方法,设计开发了具有三维笼状导电网络结构的硅/还原氧化石墨烯(Si/rGO)纳米复合材料,以该复合材料为锂离子电池负极材料,研究了Si/rGO纳米复合材料储锂性能及储能机理。结果表明:纳米Si颗粒均匀地分布在rGO三维笼状导电网络结构中,在锂离子嵌入/脱出过程中,该网络结构有效地抑制了纳米Si颗粒的体积膨胀,并且提供了更多的离子传输通道。在0.1 A/g电流密度下,Si/rGO纳米复合材料的首次放电比容量达到了1246 mA·h/g,第5次循环Coulombic效率为98.2%,容量保持率达到95.5%,表明纳米复合材料具有较快的稳定性。200次循环后,可逆容量保持在852 mA·h/g,Coulombic效率稳定在99.9%,容量保持率达到68.4%。Silicon has attracted wide attention due to its high theoretical specific capacity.However,the huge volume change and poor reaction kinetics in the lithiation process lead to a serious deterioration of its structure,a continuous capacity attenuation and a poor magnification performance,thus restricting its practical application.To solve these problems,silicon/reduced graphene oxide(Si/rGO)nanocomposites with a three-dimensional cage-like conductive structure were designed by an in-situ electrostatic self-assembly and hydrothermal reduction method with commercial Si nano-particles with the size of 60 nm and natural flake graphite.The lithium ion storage performance and energy storage mechanism of Si/rGO nanocomposite were investigated.The results show that Si nano-particles are uniformly encapsulated into a three-dimensional cage-like conductive network structure of rGO,effectively limiting the volume expansion of nano-Si particles and providing the more ion transport channels in the process of lithium ion intercalation/detachment.The specific capacity of Si/rGO nanocomposites is 1246 mA·h/g at 0.1 A/g.The Coulomb efficiency is 98.2%and the capacity retention is 95.5%from fifth cycle,indicating that the nanocomposite has a fast stability behavior.The reversible capacity remains 852 mA·h/g,the Coulomb efficiency is 99.9%,and the capacity retention is 68.4%after 200 cycles.

关 键 词：硅/还原氧化石墨烯 三维导电网络结构 储锂性能 负极材料 

分 类 号：TB332[一般工业技术—材料科学与工程]