多孔碳包覆纳米锗负极材料的制备及其电化学性能  

Preparation of porous carbon-coated nanogermanium anode materials and their electrochemical properties

作　　者：殷立雄[1] 赵津 黄剑锋[1] 李书航 宋佳琪 YIN Lixiong;ZHAO Jin;HUANG Jianfeng;LI Shuhang;SONG Jiaqi(Shanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials,School of Material Science&Engineering,Shanxi University of Science&Technology,Xi’an 710021,China)

机构地区：[1]陕西科技大学材料科学与工程学院、陕西省无机材料绿色制备与功能化重点实验室,陕西西安710021

出　　处：《南京工业大学学报（自然科学版）》2023年第5期527-536,共10页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金(51772178);陕西省科技厅重点研发计划(2020GY 257)。

摘　　要：采用高温辅助溶胶凝胶法,改变煅烧温度(750、800和850℃)制备多孔碳骨架包覆纳米锗颗粒的蜂窝状锗碳(Ge/C)复合材料。通过X线衍射仪(XRD)、X线光电子能谱仪(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N_(2)吸附脱附仪以及电化学测试等手段对不同样品进行表征分析并测试电化学性能。结果表明:800℃煅烧制得的Ge/C复合材料在电流密度为0.1 A/g时,首次放电比容量达到1255.6 mA·h/g,经100次循环后比容量仍稳定在625.4 mA·h/g,电化学性能良好。多孔结构避免了Ge的团聚,同时提供空间缓冲弱化了Ge的体积膨胀,保证了材料结构的完整性。此外,多孔结构成为离子传输的高速通道,减小了离子的扩散距离。三维碳骨架提供了电子导电路径,提高了材料整体的导电性。Honeycomb germanium-carbon(Ge/C)composites with porous carbon skeleton encapsulating germanium nanoparticles were prepared by the high-temperature-assisted sol-gel method at different calcination temperatures(750,800 and 850℃).The different samples were characterized by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),transmission electron microscopy(TEM),N_(2)adsorption-desorption apparatus,and electrochemical tests,and the electrochemical properties were analyzed.Results showed that the specific capacity of Ge/C composites prepared by calcination at 800℃reached 1255.6 mA·h/g at the first discharge at a current density of 0.1 A/g,and remained stable at 625.4 mA·h/g after 100 cycles,which showed great electrochemical performance.The porous structure avoided the agglomeration of Ge,and also provided a spatial buffer to weaken the volume expansion of Ge,thus,ensuring the structural integrity of the material.In addition,the porous structure became a high-speed channel for ion transport,reducing the diffusion distance of ions.The three-dimensional carbon skeleton provided an electron-conducting pathway,which improved the overall electrical conductivity of the material.

关 键 词：锗 电极材料 多孔碳骨架 复合材料 电化学性能 

分 类 号：TB34[一般工业技术—材料科学与工程]