Facile synthesis of Pt catalysts functionalized porous ZnO nanowires with enhanced gas-sensing properties

Abstract

Low working temperature and high sensitivity of gas sensors are critical in their practical applications; however, these properties are usually contradictory and cannot be realized simultaneously. Here, ZnO porous nanowires (PNWs) are prepared by a modified electrospinning method, and Pt nanoparticles (NPs) are doped on their surface by chemical reduction. The effects on morphology, specific surface area, and oxygen vacancy are discussed for the acetone gas-sensing performance. Results showed that Pt-ZnO PNWs responded optimally to acetone gas at 160 °C at 16.7–1.8 ppm, which was three-fold greater than that of pristine ZnO PNWs. In addition, the lowest detection limit is 50 ppb, a ten-fold lower level than pristine ZnO PNWs. The sensor exhibits superior acetone selectivity, humidity resistance, repeatability, long-time stability, noble metals, and a porous design with a large surface area, providing synergistic effects that increase the number of surface adsorption sites. Thus, the approach provided a new comprehension for loading a high-dispersibility catalyst onto the porous structure surface as a potential breath analyzer.