摘要
在ZnCl2+NH4Cl+NH3H2O电解液中采用电流密度为1 200 A/m2的恒电流制备鳞片状锌粉。通过X射线衍射分析(XRD)、扫描电镜(SEM),以及电化学测试研究锌粉的形貌结构及电结晶过程。实验结果表明,在1 200 A/m2电流密度下恒电流电解所制备的锌粉呈鳞片状结构,鳞片状锌颗粒的长径约2～3μm,厚度小于0.2μm。电解液中氨水浓度增大时,形核速率减小,不利于获得细小晶粒;Zn2+质量浓度在10～30 g/L范围内,晶核的形成速率随Zn2+浓度增加而增大;NH4Cl浓度对形核速率影响较小。在电解液中加入淀粉类添加剂,可显著提高新晶核的形成速率,有利于制备更细的电解锌粉。
Squamous zinc powder was prepared in ZnCl2＋NH4Cl＋NH3H2O aqueous solution by galvanostatic electrolysis.The structure,surface morphology and electrocrystallization process of zinc powder were investigated by X-ray diffraction（XRD）,field emission scanning electron microscopy（FESEM）,and electrochemistry analyzer,respectively.The results show that the zinc powder prepared at 1 200 A/m2 has a squamous structure with long diameter of 2~3 μm and thickness of 0.2 μm.The nucleation rate of zinc powder is low at high ammonia concentration,which is not beneficial to obtain fine grains.With the content of Zn2＋ ions increasing from 10 to 30 g/L,the nucleation rate can be improved.The concentration of NH4Cl has little effect on zinc electrocrystallization.It appears that the addition of starchy additives can remarkably enhance the nucleation rate,which leads to form finer zinc powder.
出处
《粉末冶金材料科学与工程》
EI
2011年第1期80-85,共6页
Materials Science and Engineering of Powder Metallurgy
基金
浙江省重大科技专项基金资助项目(2006C13068)
关键词
电解
鳞片状
锌粉
电结晶
添加剂
squamous zinc powder
electrochemical preparation
electrocrystallization
additive
