NO(2) Sensing Properties of Cr(2)WO(6) Gas Sensor in Air and N(2) Atmospheres

Gas sensors were fabricated from Cr(2)WO(6) nanoparticles for NO(2) detection. Low dimensional materials Cr(2)WO(6) were prepared by a wet chemistry method followed by hydrothermal treatment. The morphology of the nanoparticles and their sensing properties to NO(2) were investigated in both dry and humid conditions. Additionally, the sensing response was also characterized in a non-oxygen condition. It was concluded that the sensor responses in N(2) conditions were higher than that in air conditions at 200°C. Moreover, the sensing characteristics were inhibited by water vapor at 200°C. The oxygen adsorption behavior was also investigated to verify the basic sensing mechanism of Cr(2)WO(6) in the absence and presence of NO(2) and water vapor separately. Based on the power law response, it was indicated that both NO(2) and water vapor have a strong adsorption ability than oxygen ions of Cr(2)WO(6) sensors.