Abstract: Metal oxide semiconductor sensor has attracted an increasing number of attention and applied to the detection of hazardous gases because of small size, low cost and convenient usage and so on. The sensing material is the core of the gas sensor. In this paper, research progress of oxide semiconductor BTEX gas sensors in recent years are reviewed. The microstructure, loading/doping modification, gas-sensing performance, gas-sensing mechanism and main problems of sensing material in recent years are analysed. Furthermore, the prospect of BTEX gas sensor is discussed.
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