SnO_2-LiZnVO_4系湿敏元件电容特性分析

采用共沉淀法制备SnO2-LiZnVO4系湿敏材料,研究了LiZnVO4的掺杂量对材料湿敏电容的影响。结果表明:LiZnVO4的掺杂量,环境的相对湿度(RH)、测试信号频率对湿敏电容有较大影响。当x(LiZnVO4)为10%时,可使材料具有合适的低湿电容和灵敏度。在100Hz下,当环境的RH从33%上升到93%时,SnO2-LiZnVO4系湿敏材料制备的湿敏元件的电容增量可达起始值的2300%,显示出较高的电容湿度敏感性。湿敏元件的电容响应时间约为54s,恢复时间约为60s。湿滞约为RH6%。

Capacitive characteristic analysis of SnO_2-LiZnVO_4 system humidity sensor

SnO_2-LiZnVO_4 system humidity sensing materials were prepared by co-precipitation method.The influence of LiZnVO_4-doped amount on humidity sensing capacitance of this material was studied.The results show that the humidity sensing capacitance strongly depends on the LiZnVO_4-doped amount,relative humidity (RH) of environment,and frequency of measured signal.This humidity sensing material with proper capacitance at lower humidity and sensitivity can be made by doped amount of 10% of LiZnVO_4 (mole fraction).The capacitance increment of humidity sensor prepared by humidity sensing material of SnO_2-LiZnVO_4 system is 2 300% of its initial value when RH of environment is increased from 33% to 93% at 100 Hz,indicating higher capacitance humidity sensitivity.Of the humidity sensor,the capacitance response time for RH-increasing process is about 54 s and recovery time for RH-decreasing process is about 60 s,and the hysteresis is about RH 6%.