Enhanced benzene sensing property of Au-Pd@ZnO and Au-Pt@ZnO core-shell nanoparticles: The function of Pt/Pd decorated Au-ZnO hetero-interface

Core-shell Au@ZnO, Au-Pd@ZnO and Au-Pt@ZnO nanoparticles were synthesized, aiming at figuring out the function of Au-ZnO hetero-interfaces. Pd/Pt was decorated on Au cores which were confirmed by using various techniques. The optimal operating temperature of all synthesized core-shell NPs based sensors (300 °C) is much lower than ZnO NPs (400 °C). By comparing gas sensing properties towards ppb-ppm level benzene, the Au-Pd@ZnO and Au-Pt@ZnO nanoparticles had better benzene sensing property than Au@ZnO nanoparticles. The Pt/Pd decorated Au-ZnO hetero-interface had positive influence on benzene sensing performance, because decoration of Pt and Pd further enhanced electron transfer phenomenon on Au-ZnO hetero-interfaces which was advantageous on benzene sensing property.