无机杂质对改善纳米BaTiO_3湿敏特性的作用

Action of Inorganic Impurities for Improving the Humidity Semsitivity of Nanocrystalline BaTiO_3

用硬酯酸盐法合成了纳米ＢａＴｉＯ３材料，它对湿度有良好的敏感性能。在纳米ＢａＴｉＯ３中掺入少量杂质，会影响其感湿性能。本文研究了掺杂方法、掺杂种类及掺杂浓度对纳米ＢａＴｉＯ３湿敏元件的电阻和湿滞的影响。混合掺入Ｎａ２ＣＯ３和ＮａＨ２ＰＯ４可以使纳米ＢａＴｉＯ３湿敏元件的电阻为１０６～１０３Ω，湿滞＜３％。

Nanocrystalline BaTiO_3 was synthesized by stearic acid method and showed good humidity sensitivity. Doping a little amount of impurities could influence the humidity sensing properties of nanocrystalline BaTiO_3. In this paper, the influence of the method, species and concentration of dopants on the resistance and humidity hysteresis of BaTiO_3 humidity sensor was investigated. A mixed doping of Na_2CO_3 and NaH_2PO_4 resulted in the resistance of 10~6～10~3Ω and the hysteresis of <3% r.h.