Experimental and Theoretical NO<i>_x</i> Physisorption Analyses of Mesoporous Film (SBA-15 and SBA-16) Constructed Surface Photo Voltage (SPV) Sensor

Abstract

Mesoporous silica films with hexagonal (SBA-15) and cubic (SBA-16) mesostructures have been successfully employed to fabricate surface photo voltage (SPV) sensors for NO2 gas. These SPV sensors exhibited better sensitivity (S) in 50 ppm NO2 gas than in 100 ppm NO gas. SPV with SBA-16 film showed better sensitivity in 1 ppm NO2 gas than in 1 ppm NO gas. These phenomena can be explained by the physical adsorption of the target gas into the mesoporous layer, which is regarded as the insulator layer in metal−insulator-semiconductor (MIS) devices.