Hybrid nanostructures of Ag/Au-ZnO synthesized by pulsed laser ablation/irradiation in liquid

Abstract

In this study, properties of zinc oxide (ZnO) are tuned by forming hybrid nanomaterials via pulsed laser ablation and irradiation in liquid. Ag/Au bimetallic nanocolloids synthesized by pulsed laser ablation in water are mixed with ZnO powder followed by laser irradiation to form Ag/Au-ZnO nanohybrids. The optical absorption spectra of the hybrid nanomaterials show the presence of plasmonic peaks of Ag/Au. The morphological studies of the nanohybrids reveal the changes in mixed non-uniform morphology to spherical ones. From the structural analysis, the stability of crystalline structure of ZnO is evidenced in all samples, and the high-resolution transmission electron microscopic images showed atomic fringes that correspond to ZnO and Ag/Au. Elemental analysis revealed the compositions from Zn, O, Ag, and Au and their chemical states are confirmed by X-ray photoelectron spectroscopy. Thin films of Ag/Au-ZnO hybrid nanomaterials were fabricated by doctor blade method and annealing effects on morphology, homogeneity of composition and optical properties promoted the visible-light photocatalytic activity. Samples with bimetallic nanoparticles of higher ablation duration showed better photocatalytic performance. Results of this study show the effectiveness of laser ablation and irradiation in liquid technique as a unique green synthesis for obtention of plasmonic hybrid nanomaterials.