Examining the Gas Sensing Properties of the Nanocrystalline Sm2O3-WO3

In this study, nanocrystalline (NC) WO3 and Sm2O3-WO3 gas sensors have been synthesized and deposited on Al2O3 substrate by gas condensation method, then sintering to 600℃. SEM is used to observe the morphology of the surface. TEM is used to measure the particle size. The resistance of sensor is measured in different temperatures and gas concentration to evaluate the sensing properties of NC WO3 and NC Sm2O3-WO3 sensor. The results indicate that WO3 is a usability gas sensor material. After Sm2O3 is doped in WO3, it does not obviously influence CO detection; it owns better sensitivity and stability. To UV irradiation on WO3, the sensitivity of WO3 is enhanced and it maintains WO3 recovery properties in NO2 detecting. UV irradiation on Sm2O3 doped WO3 does not show enhanced well properties as UV illuminate on WO3.