Zinc oxide incorporated molybdenum diselenide nanosheets for chemiresistive detection of ethanol gas

Herein, a room-temperature chemiresistive ethanol gas sensor based on hydrothermally synthesized zinc oxide (ZnO) incorporated-molybdenum diselenide (MoSe2) nanosheets was demonstrated. The sensing properties of the MoSe2/ZnO nanocomposite sensor were investigated systematically by exposing the sensor to various ethanol gas concentrations (10-500 ppm) in dry N2 and dry air. The synergistic effect due to the incorporation of ZnO nanorods in MoSe2 nanosheets was found to enhance the sensor response to ethanol gas (when operated in dry N2) with improved response and recovery time of 8.4 and 14.7 s re-spectively, high selectivity, stability, and reproducibility. The nanocomposite-based sensor showed high gas sensing response (Rg/Ra) of 37.8 to 500 ppm of ethanol gas. While the response of the nanocomposite-based sensor decreased to 15.3, to 500 ppm of ethanol gas in dry air which suggests that the sensor performs better when operated in dry N2 than in dry air. On the basis of experimental results, a plausible mechanism has been proposed based on the formation of p-n heterojunction and potential barrier modulation at the interface of the MoSe2/ZnO nanocomposite sensor. The results demonstrated that MoSe2/ZnO-based na-nocomposite may pave the way for the fabrication of ethanol gas sensors for real-time electronics appli-cations. (c) 2023 Elsevier B.V. All rights reserved.