ZnO-C三维网络结构涂层的制备及其储锂性能研究

通过简单的刮涂工艺成功地在铜箔表面制备出具有三维网络结构的ZnO-C复合涂层。采用X射线衍射(XRD)、拉曼光谱(Raman)、扫描电镜(SEM)和透射电镜(TEM)对复合涂层的晶体结构及微观形貌进行研究。结果表明: 该涂层由宽度为0.1~1 μm的碳基枝条相互连接形成连续的三维网络结构, 碳基枝条内包含ZnO纳米粒子和尺寸约为2 nm的微孔。该涂覆在铜箔表面的复合涂层可直接用作锂离子电池的负极。电化学测试结果表明: ZnO-C复合涂层负极材料在0.1 A/g电流密度下经过100次循环后的比容量为855 mAh/g, 并且在循环过程中未出现容量衰减现象; 在5A/g大电流密度下的比容量为418 mAh/g, 是0.1 A/g电流密度下比容量的51.3%。

Fabrication and Lithium Storage Performance of ZnO-C Three Dimensional Network Coatings

Cu-supported ZnO-C composite coatings with three dimensional (3D) network structures were successfully fabricated through simple knife coating technique. The structure and morphology of the as-prepared samples were characterized by X-ray diffraction (XRD), Raman spectrum (Raman), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that the coatings are constructed by interconnected carbon based branches with a width of 0.1-1 μm containing ZnO nano-particles and micro-pores with a size of ~2 nm. The Cu-supported ZnO-C composite coatings can be directly employed as anodes of lithium-ion batteries (LIBs). The electrochemical test demonstrates that at a current density of 0.1 A/g, the ZnO-C composite coating electrodes exhibit specific capacity of 855 mAh/g after 100 cycles without capacity fading during cycling; at a high current density of 5 A/g, the electrodes deliver specific capacity of 418 mAh/g, which is 51.3% of the specific capacity at a current density of 0.1 A/g.