A 2-chloroethyl ethyl sulfide (2-CEES) gas sensor based on a WO3/graphite nanocomposite with high selectivity and fast response-recovery properties

Abstract

Sensitive detection of toxic and harmful gases is essential in the field of environmental monitoring and human health. Among the detection strategies, gas sensors based on metal oxides are widely adopted. However, the gas sensor based on a single metal oxide has some problems such as poor selectivity and long response recovery time, which limit its further practical application. This paper is committed to improving the selectivity and shortening the response-recovery time toward 2-chloroethyl ethyl sulfide (2-CEES, dichlorodiethyl sulfide simulation). Tungsten oxide (WO₃)/graphite nanocomposites were prepared by simple blending, and the sensing performance toward 2-CEES gas was explored. The experimental results show that the WO₃/graphite gas sensor with a WO₃ mass fraction of 97% exhibits excellent sensing performance. In more detail, the device has a high response of 63% for 5.70 ppm 2-CEES at a working temperature of 260 °C, a fast response-recovery time (8 s/34 s) and high selectivity compared with ammonia, acetone, ethanol, and other toxic gas simulation gases [dimethyl methylphosphonate (DMMP) and acetonitrile]. This study provides an effective strategy to realize a high-performance gas sensor for dichlorodiethyl sulfide.