X-ray-induced synthesis of Au nanoparticles on ZnO nanowire arrays

Abstract

Abstract We report the synchrotron X-ray-induced synthesis of plasmonic Au nanoparticles (NPs) on ZnO nanowire (NW) arrays. By X-ray irradiation at room temperature, Au NPs were synthesized from an aqueous solution containing HAuCl4 and NaHCO3. Samples prepared in continuous and scanning exposure modes were examined by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy and Raman spectroscopy. In the continuous exposure mode, a match-like Au ZnO structure was dominantly observed. We found that the scanning mode is suitable for the synthesis of monodisperse Au NP-ZnO NW heterostructures. The average diameter of the Au NPs was approximately 11.8 nm. The peak intensity of the E2(high) mode doubled and the 2E2 peak can be clearly observed in Raman spectrum of Au NP-ZnO NW heterostructure. These changes are evidence of the surface plasmon resonance effect due to the Au NPs.