Synthesis of Au-ZnO hybrid nanostructure arrays and their enhanced photocatalytic activity

The preparation of an Au-ZnO hybrid nanostructructure array on a TCO substrate has been achieved via annealing an Au coated ZnO nanorod array in a nitrogen atmosphere. The characterization of the morphology and the structure of the Au-ZnO hybrid nanostructructure were carried out with X ray diffraction, scanning electron microscopy and transmission electron microscopy. Photoluminescence spectra give a quenched luminescent emission because of the charge separation in the prepared Au-ZnO hybrid nanostructructure. It is worth pointing out that the prepared Au-ZnO hybrid nanostructructure presents superior photocatalytic activity over ZnO nanorods in the case of the degradation procedure of methyl orange. It is found that an 8 ml methyl orange aqueous solution (2.5 ppm) could be totally degradated with 4 sheets of Au-ZnO hybrid nanostructructure (12 x 12 mm(2)) within 4 hours.