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

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 HAuCl 4 and NaHCO 3 . 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 E 2 (high) mode doubled and the 2 E 2 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.