Au nanoparticle modified flower-like ZnO structures with their enhanced properties for gas sensing

The flower-like ZnO (F-ZnO) synthesized by a solution approach was hydrothermally functionalized with Au nanoparticles (Au NPs). The Au coverage on the surface of F-ZnO was controllable by adjusting the Au concentration of the precursor. The gas sensing performance of the formed hybrid was systematically investigated. A Au-functionalized F-ZnO hybrid structure, combining excellent catalytic activity of Au NPs and efficient charge-transfer layer at the Au/ZnO interface, was demonstrated to possess the superior response to pristine ZnO. The optimal Au loading is 6 wt%, and its gas response is nearly 17 times higher than that of pristine ZnO and ~2.5 times higher than that of commercial ZnO functionalized with 6 wt% Au. Such a hybrid structure exhibits a great potential for gas sensing applications.