电沉积制备结构和性能可控的纳米结构硅合金膜层的研究

项目名称： 电沉积制备结构和性能可控的纳米结构硅合金膜层的研究

项目编号： No.51474107

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 矿业工程

项目作者： 李冰

作者单位： 华东理工大学

项目金额： 80万元

中文摘要： 采用廉价SiCl4-AlCl3/盐酸三甲胺离子液体，在无外加模板的条件下,依靠离子液体中阳离子在电极表面的吸附作用，在Cu基体上直接电沉积制备Si/Al合金纳米线和多孔纳米膜。研究Si/Al络合离子结构、电化学还原机理和Si/Al的形核和长大机理。采用循环伏安曲线、电化学阻抗谱和电化学原位拉曼光谱研究Cu/离子液体界面结构、阳离子吸附形式与电位之间的关系，从而通过控制电位控制阳离子在电极的吸附能力。交替采用电位/反向电位制备Si/Al合金纳米线，以及交替采用多步正向电位脉冲/反向电位制备多孔纳米膜。反向电位使Si/Al合金的Al元素选择性溶解，以降低纳米线直径和增加纳米膜孔道和降低颗粒的尺寸。通过研究电位、电流、反向电流和电位，以及电解质组成和温度对Si/Al合金形貌和结构的影响，调控Si/Al合金纳米线和多孔纳米结构,优化Si/Al合金作为锂离子电池负极的电化学循环性能和倍率性能。

中文关键词： 电沉积；硅合金；结构；性能

英文摘要： According to cation adsorption of the ionic liquid onto the electrode, direct electrodeposition of Si/Al alloy nanostructures with either nanowires or porous nanoparticles films onto Cu substrates in a low-cost SiCl4-AlCl3/TMHC ionic liquid without template are proposed. The complex ion structures of the Si and Al in the ionic liquid, electrochemical reduction mechanism and the nuclei formation and growth mechanisms of both Si and Al are investigated. Cyclic voltammograms, electrochemical impediance as well as electrochemical Raman scattering (SERS) in site are used to investigate the interface structure of Cu/ ionic liquid , and the relation of the cation adsorption with the applied potential on the electrode, then the potential or current is used to control the ability of the cation adsorption on the electrode.Alternate positive potential pulse and reverse potential pulse are applied to prepare Si/Al alloy nanowires and multi-steps positive potential pulse and reverse potential pulse to prepare porous films composing of nanoparticles. Reverse potential pulses are used to dissolve Al from Si/Al alloy to reduce the diameter of the nanowires and also increase the porosity of the films and reduce the size of the particles. The effects of the electrochemical parameters such as potential，current and reverse current (potential) and of the technological parameters such as the temperature and electrolyte composition on the structure and morphology of the Si/Al alloy are characterized. The cyclic and rate performances of Si/Al alloy anode as the Li ion battery are optimized by adjusting the Si/Al alloy nanowires and porous nano-particle film structures.

英文关键词： electrodeposition;Si alloy;structure;property