Highly Sensitive and Selective Sensing of HS Gas Using Precipitation and Impregnation-Made CuO/SnO Thick Films.

In this work, CuO-loaded tetragonal SnO nanoparticles (CuO/SnO NPs) were synthesized using precipitation/impregnation methods with varying Cu contents of 0-25 wt% and characterized for HS detection. The material phase, morphology, chemical composition, and specific surface area of NPs were evaluated using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller analysis. From gas-sensing data, the HS responses of SnO NPs were greatly enhanced by CuO loading particularly at the optimal Cu content of 20 wt%. The 20 wt% CuO/SnO sensor showed an excellent response of 1.36 × 10 toward 10 ppm HS and high HS selectivity against H, SO, CH, and CH at a low optimum working temperature of 200 °C. In addition, the sensor provided fast response and a low detection limit of less than 0.15 ppm. The CuO-SnO sensor could therefore be a potential candidate for HS detection in environmental applications.