共沉淀法制备掺杂氧化锌压敏陶瓷粉料热力学分析

Thermodynamic Analysis on Preparing Doped Zinc Oxide Varistor Ceramic powders by Coprecipitation Process

本文通过对Ｍｅｎ＋（Ｚｎ２＋；Ｃｒ３＋，Ｍｎ２＋；Ｓｂ３＋，Ｂｉ３＋，Ｃｏ２＋）－ＮＨ３－ＣＯ３２－－Ｈ２Ｏ体系进行热力学分析的基础上，获得了Ｍｅ－ＮＨ３－ＣＯ３２－Ｈ２Ｏ体系中的ｌｇ［Ｍ］－ｐＨ关系图，得到了用ＮＨ４ＨＣＯ３和ＮＨ３·Ｈ２Ｏ作沉淀剂，用共沉淀法制备掺杂氧化锌压敏陶瓷粉料时，最佳共沉淀ｐＨ为７．０左右．

Based on the thermodynamic analysis of Men+ (Zn2+, Cr3+ , Mn2+, Sb3+, Bi3+, Co2+)-NH3CO2---H2O systems, the curves about lg[M]T-pH of Mn+-NH3-CO32--H2O systems were obtained.It shows that the optimal pH is 7.0 to prepare doped zinc oxide varistor ceramic powders bycoprecipitation process, and the precipitants are NH4HCO3 and NH3.H2O.