SnO_2-LiZnVO_4系棒状与球形晶粒湿敏陶瓷特性研究

Study on the Property of Humidity-sensitive Ceramics of SnO_2-LiZnVO_4 with Rod and Ball Shaped Grains

对比研究了尿素共沉淀法和氨水共沉淀法制备出SnO2-LiZnVO4系湿敏陶瓷的显微结构和湿敏特性,考察了液相掺杂LiZnVO4对材料湿敏特性的影响。实验结果表明,采用尿素共沉淀法制备出的SnO2-LiZn-VO4系湿敏材料具有棒状晶粒的微结构,而采用氨水共沉淀法制备出的该系湿敏材料具有球形晶粒的微结构。湿敏特性表明,2种微结构的湿敏材料都是液相掺杂LiZnVO4的摩尔分数为10%时可使材料湿敏性能最好。但棒状晶结构的SnO2-LiZnVO4系湿敏材料低湿电阻更小,灵敏度更适中。频率特性表明,测试频率对2种试样的阻抗-相对湿度特性曲线影响都较大。稳定性分析表明,棒状晶结构的试样比球形晶粒结构的试样更稳定。

The microstructure and humidity-sensitive characteristics of SnO2-LiZnVO4 system humidity-sensitive ceramics were studied by comparing the method of urea co-precipitation with the method of ammonia co-precipitati- on. The influence of the amount of liquid-doped LiZnVO4 on the humidity-sensitive characteristics was researched. The experimental results showed that the SnO2-LiZnVO4 system humidity-sensitive material prepared by the co-pre- cipitation with urea and ammonia were characterized by the rod and ball shaped grains respectively. Humidity-sensi- tive characteristics indicated that humidity-sensitive characteristics of the material is best with 10% liquid-doped LiZnVO4 in the both co-precipitation SnO2 powders. But the material with rod shaped grains characterized lower re- sistance at lower humidity and with proper humidity sensitivity than that with ball grain. The characteristics of fre- quencies showd that the material with rod and ball grain both have better respond to frequencies. The characteristics of stabilizations showed that the sample with rod shaped grains was more stationary than that with ball shaped grains.