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

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 degrees 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.