Studies of NO 2 Gas-Sensing Characteristics of a Novel Room-Temperature Surface-Photovoltage Gas Sensor Device.

In this work the characteristics of a novel type of room temperature NO2 gas sensor device based on the surface photovoltage effect are described. It was shown that for our SPV gas sensor device, using porous sputtered ZnO nanostructured thin films as the active gas sensing electrode material, the basic gas sensor characteristics in a toxic NO2 gas atmosphere are strongly dependent on the target NO2 gas flow rate. Moreover, it was also confirmed that our SPV gas sensor device is able to detect the lowest NO2 relative concentration at the level of 125 ppb, with respect to the commonly assumed signal-to-noise (S/N) ratio, as for the commercial devices.