介绍了一种新型Li_2SnO_3厚膜湿敏元件。用X-射线粉末衍射图和电子能谱分析了该湿敏元件感湿体的组成和价态。由这种材料的物理机制和极化机制,建立了等效电路模型。用复阻抗分析法分析了感湿机理并得出如下结论:(1)晶界表面电阻随相对湿度上升而下降,是主要敏感部分。(2)导电载流子不只是氢离子或水合氢离子而且还有锂离子。(3)在高湿下存在电解质电导。 A new Li 2 SnO 3 thick film humidity sensor is introduced. The composition and valence state of the wetted element were analyzed by X-ray powder diffraction and electron spectroscopy. Based on the physical mechanism and polarization mechanism of this material, an equivalent circuit model is established. The complex sensitivities were analyzed by complex impedance analysis and the following conclusions were obtained: (1) The surface resistivity of grain boundary decreased with the increase of relative humidity, which was the main sensitive part. (2) The conductive carriers are not only hydrogen ions or hydronium ions but also lithium ions. (3) There is electrolyte conductance under high humidity.