Highly Sensitive and Selective Defect WS₂ Chemical Sensor for Detecting HCHO Toxic Gases

The gas sensitivity of the W defect in WS₂ (V_W/WS₂) to five toxic gases-HCHO, CH₄, CH₃HO, CH₃OH, and CH₃CH₃-has been examined in this article. These five gases were adsorbed on the V_W/WS₂ surface, and the band, density of state (DOS), charge density difference (CDD), work function (W), current-voltage (I-V) characteristic, and sensitivity of adsorption systems were determined. Interestingly, for HCHO-V_W/WS₂, the energy level contribution of HCHO is closer to the Fermi level, the charge transfer (B) is the largest (0.104 e), the increase in W is more obvious than other adsorption systems, the slope of the I-V characteristic changes more obviously, and the calculated sensitivity is the highest. To sum up, V_W/WS₂ is more sensitive to HCHO. In conclusion, V_W/WS₂ has a great deal of promise for producing HCHO chemical sensors due to its high sensitivity and selectivity for HCHO, which can aid in the precise and efficient detection of toxic gases.