电沉积纳米晶制备核-壳结构粉体机理及粉体电镀的研究

项目名称： 电沉积纳米晶制备核-壳结构粉体机理及粉体电镀的研究

项目编号： No.21476066

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 有机化学

项目作者： 胡波年

作者单位： 湖南工学院

项目金额： 90万元

中文摘要： 本项目采用电沉积的方法在粉体表面形成纳米晶镀层，制备金属包覆的复合粉体材料。研究的目的是阐明在石墨粉体（轻质粉体）、钨粉和碳化钨粉（重质粉体）上电沉积金属铜、镍或钴，制备核壳结构的粉体复合材料的机理。研究金属包覆产品的分散性能，研究电沉积的电流效率和析氢动力学机理。揭示粉体表面电沉积纳米晶镀层的沉积规律。研究电解液的组成和导电粉体在镀液中的分散行为。通过控制电流、电压、电解液组分及其它参数，来提高成核的密度和控制镀层的组分、晶粒组织、晶粒大小。通过在大电流密度下电沉积产生析氢反应，有效控制金属沉积在粉体表面，而不粘附电极。通过合适的搅拌方式防止粉体团聚和结块。通过粉体与阴极的不断碰撞和接触获得电子，置换溶液中的金属离子，还原成金属沉积在粉体表面形成纳米晶镀层。本项目的研究能揭示粉体与阴极板碰撞沉积电镀的新规律，为大批量生产先进的金属包覆复合材料提供相应的电化学理论基础。

中文关键词： 电沉积；纳米晶；机理；金属包覆粉体；粉体电镀

英文摘要： This project focuses on the fabrication of nanocrystal coatings on the surface of powders by electrodeposition. The goal is to understand the mechanism of the formation of core-shell structures of composite powders in the processes of electrodepositing copper, nickel and cobalt on graphite (light powders), tungsten, and tungsten carbide (heavy powders) powders. The dispersibility of metal coated powders, the current efficiency of electrodeposition, and the dynamic mechanism of hydrogen evolution will also be explored. The composition of the electrolyte and the dispersing behavior of conducting powders in the electrolyte will be examined for controlling the coating composition, grain structure and grain size. The metals will be effectively deposited on the surface of powders, not on the negative plate since hydrogen gas is evolved under large current density. Agglomeration of powders will be avoided by effective stirring. Electrons are acquired on the powders by continuous collision or contact of powders on the negative plate, leading to the deposition of the metal on the surface of powders to form nanocrystal coating. Factors controlling the electroplating processes on negative plate will be revealed. Insights into the electrochemical deposition processes will be gained, which will be useful for large-scale production of advanced metal coated composite powders.

英文关键词： Electrodeposition;Nanocrystal;Mechanism;Metal coated powder;Powder electroplating