WS₂ Nanostructure-Based Gas Sensor for SF₆ Decomposition Products: Experimental and First-Principles Study

Pompon-like WS2 nanostructure-based gas sensor was fabricated, and the sensing performance with micromechanism to SF6 decompositions was discussed. At optimal working temperature, the sensor experiences resistance increasing for all four SF6 decompositions (SO2, SOF2, SO2F2, and H2S). At low concentration (0–50 ppm), the sensor shows high linearity (R2 > 0.99), and the rank of the sensitivity is: H2S>SO2>SO2F2>SOF2. Furthermore, the first-principles results indicate that the different sensitivity is derived from the chemical interactions and electron transfer between the adsorbed molecule and the edge structures of WS2. This work gives experimental and theoretical support of transition metal dichalcogenide (TMDC)-based gas sensor to detect SF6 decompositions and provides insights to design high-performance TMDC-based gas sensor from theoretical aspect.