Enhanced acetone-sensing properties of pt-decorated al-doped ZnO nanoparticles

Abstract

We report the excellent sensing performance of Pt-decorated Al-doped ZnO (Pt-AZO) nanoparticles (NPs) for the detection of the hazardous gas, acetone. The Pt NPs were uniformly deposited on the surface of the Al-doped ZnO (AZO) NPs via magnetron sputtering under agitation. The Pt-AZO NPs show remarkably enhanced sensing properties with a sensing response and response time of 421 and 2.9 s, respectively, under exposure to 10 ppm acetone at 450 °C, as compared with those of pure ZnO NPs (17 and 51 s, respectively), AZO NPs (56 and 15 s, respectively), and Pt-decorated ZnO (Pt-ZnO) NPs (261 and 7 s, respectively) under the same conditions. Furthermore, the Pt-AZO NPs showed the highest sensing response to 10 ppm acetone compared to those reported so far for metal-oxide sensing materials. Pt NPs played a crucial role in improving the gas sensing performance of AZO NPs. The catalytic effect of Pt NPs led to a greater number of absorbed oxygen ion species on the surface of the Pt-AZO NPs, as indicated by the increased number of oxygen vacancies, higher carrier concentration, larger specific surface area, and enhanced reaction kinetics. The outstanding sensing performance of the Pt-AZO NPs as compared to those of pure ZnO, AZO, and Pt-ZnO NPs is attributed to these synergic effects.