【作者】 童震坤； 方姗； 郑浩； 张校刚；

【Author】 Zhenkun Tong;Shan Fang;Hao Zheng;Xiaogang Zhang;Jiangsu Key Laboratory of Materials and Technology for Energy Conversion,College of Material Science and Engineering,Nanjing University of Aeronautics and Astronautics;

【机构】 江苏省能量转换材料与技术重点实验室南京航空航天大学材料科学与技术学院；

【摘要】 以二氧化锗和二水合醋酸锌为原料,采用水热法制备了锗酸锌纳米棒,并将其与氧化石墨烯复合,制备了石墨烯包覆的锗酸锌纳米棒三维复合材料。SEM等测试表明,锗酸锌纳米棒均匀地附着在石墨烯片上,阻止了石墨烯片之间相互堆垛,而石墨烯片层之间相互连接,既形成了三维的空间导电网络,提高了材料的电子导电性。电化学测试表明,石墨烯片作为稳定的框架,能够有效缓冲活性物质在脱嵌锂过程中产生的体积变化,在500 m A·g^-1电流密度下循环190次后,Zn2Ge O4@RGO复合材料的嵌锂容量仍有1189.5mA h·g^-1;在3.2 A·g^-1的大电流密度下,嵌锂容量达到449.5 mA h·g^-1。表明该复合材料具有优异的长循环稳定性和良好的倍率性能。更多还原

【Abstract】 Zn₂GeO₄ nanorods were synthesized through a hydrothermal method by using GeO₂ and Zn（CH₃COO）₂·2H₂O. Then, the Zn₂GeO₄ nanorods were filtrated with RGO. It is indicated by Materials characterization that Zn₂GeO₄ nanorods were firmly adhered on the surface of graphene sheets, which can effectively avoid the stacking of graphene sheets. The graphene sheets connected with each other to form an electric conductive network can improve the electrical conductivity of the composite. The electrochemical measurement show that the 3D architecture electrode which worked as a stable framework to accommodate the volume change of active material during Li+ insertion/extraction exhibited excellent electrochemical performances. It delivers a specific capacity of 1189.5 mA h·g^-1 at 500 mA ·g^-1 after 190 discharge/charge cycles. Even at a high current density of 3.2 A·g^-1, the capacity can maintain 449.5 mA h·g^-1. These results indicate that the composite possess outstanding long-time cycling stability and excellent rate capability.更多还原