SnO_2-LiZnVO_4系湿敏陶瓷烧结工艺与电性能关系的复阻抗分析

Complex Impedance Analysis for the Relationship of Calcining Process and Sensing Properties of SnO_2-LiZnVO_4 Humidity Ceramic

采用共沉淀法制备出SnO2-LiZnVO4系湿敏试样,分别在不同烧结温度和保温时间下于空气中烧成,测量试样的湿敏特性,并通过复阻抗分析方法,研究了SnO2系湿敏元件烧结工艺与电性能的关系,探讨烧结工艺对敏感材料微结构的影响.结果表明:适当调整烧结工艺参数可明显改善材料的微结构和湿敏性能,850℃×1h试样具有高湿电阻小灵敏度适中的湿敏特性;复阻抗分析表明,试样的电容在低频范围随烧结温度的升高和保温时间的延长先减小后增大,但高频范围几乎不随烧结温度的变化,且随时间的延长,试样的复阻抗谱的半圆弧弧长逐渐增大.

SnO2-LiZnVO4 system humidity-sensitive ceramics were prepared by co-precipitation and calcined at different temperature and time. By measuring the sensitivity and using complex impedance analysis, the effects of calcining temperature and time on sensing properties and microstructure of the samples were researched. Humidity sensitive and microstructure characteristics of humidity sensitive material can be improved by controlling the calcining process parameters. Complex impedance analysis indicates that the capacitance of the sensor first decreases then increases as calcining temperatures and time increase, especially for low measurement frequency. The semicircular arc of complex impedance reduces as calcining time increases.