Humidity-sensitive properties and conductance mechanisms of SnO2–K2O–LiZnVO4

The SnO2–K2O–LiZnVO4 materials were prepared using the coprecipitation process. We examined the effects of liquid-phase doping of potassium (K+) on the humidity-sensitive characteristics of the nano-materials. Direct current (DC) measurements were used to investigate the mechanisms of electrical conductance of the SnO2–K2O–LiZnVO4 materials. The results demonstrated that by appropriately doping of K+ ions, a humidity-sensitive material with low resistance and moderate sensitivity could be obtained. The analysis on DC characteristics revealed a mixed electronic–ionic mechanism of electrical conductance. It was suggested that the liquid phase potassium doping at the [K] concentration of 2.5 mol% could improve the humidity-sensing performance of the nano-materials.