共沉淀纳米掺杂制备ZnO压敏电阻数学模拟

A Model of Coprecipitation Doping for Preparing ZnO Varistor Ceramic Powders

摘要:

从多种离子反应平衡角度,对氨法共沉淀过程进行了理论分析,并在此基础上提出了氨法共沉淀的数学模型和计算方法.对ZnO压敏电阻粉体共沉淀反应中的只能与OH-络合的金属离子(B类离子)的单体沉淀、共沉淀,以及A类(既能与NH3也能与OH-络合的金属离子)、B类离子的共沉淀进行了理论分析和模拟计算,得到了沉淀反应中沉淀系数、络合反应系数及pH值和氨水添加量之间的关系.

关键词:ZnO压敏电阻;共沉淀;数学模拟;共沉淀;纳米掺杂;压敏电阻;数学模拟;Powders;Ceramic;Varistor;Doping;Coprecipitation;关系;添加量;氨水;反应系数;模拟计算;单体;金属离子;沉淀反应;粉体;计算方法;数学模型

Abstract:

This paper presents a study of the precipitation and coprecipitation of the B species ions which can be only complexed with hydroxyl by a numerical stimulation method based on the mechanism of balance on multi-ions reaction. The coprecipitation of A and B species ions is also investigated. The dependences of coprecipitation rate, side reaction rate and pH value on the ammonia contents are exhibited and discussed.

Key words:ZnO varistor; coprecipitation; numerical stimulation