UV-Activated NO2 Gas Sensing: Photoactivated Processes on the Surface of Metal Oxides
Pavel Kutukov1, Daria Kurtina1,2, Sergey Maksimov1
1Chemistry Department, Moscow State University, 119991 Moscow, Russia.
Abstract:
In recent years, wide bandgap metal oxide semiconductors have become the base materials of choice for semiconductor gas sensor design. In this work, nanocrystalline ZnO, In2O3, and SnO2 were investigated when detecting NO2 under UV-photoactivation conditions. The materials were characterized by XRD, low-temperature nitrogen adsorption, and electron microscopy. The article considers the mechanism of sensor signal formation, as well as the mechanism of action of UV-light photoactivation, using an in situ multi-method approach. In situ mass spectrometry and in situ TR-DRIFTS were employed to study the impact of UV-light photoactivation on target gas adsorption equilibrium as well as the electrical and gas-sensing properties of the materials.


