A Review of Resistive Gas Sensors Based on Semiconducting Metal Oxides

Nowadays, the industrialization of societies and the improvement of the quality of life are associated with issues such as air pollution and environmental pollution. Hence, gas sensors are widely used to detect toxic and hazardous gases and vapors in various applications. Among the different gas sensors, resistive gas sensors based on semiconducting metal oxides, its work is based on changes in sensor resistance in the presence of the target gas, are among the most popular types of gas sensors. These sensors have high sensing response, short response and recovery time, high physical and chemical stability and low price. In this review article, resistive gas sensors based on semiconducting metal oxides are discussed. Various aspects of fabrication, gas sensing mechanism, strategies of improving sensing properties, and methods of reducing energy consumption in these sensors are explained. This article is organized and written in such a way as to provide the basic concepts for those interested in entering this field.