ZnO/Polyethylene-Glycol and ZnO/Au Nanocomposites for Enhanced Photocatalytic Degradation of Organic Dye

摘要

A facile method has been used for the synthesis of Zn@ZnO/polyethylene-glycol and ZnO/Au nanocomposites. A pure zinc plate was laser ablated in deionized water, aqueous solution of surfactant sodium dodecyl sulfate (SDS), Polyethylene glycol (PEG) and colloidal solution of gold nanoparticles to form nanocomposites with different surface functionality. Both SDS and PEG reduce the rate of surface oxidation and provide an effective control on surface ZnO layer volume. Absorption spectra confirmed oxidation of Zn in water, SDS and PEG and formation of composite Zn@ZnO core-shell particles. The ZnO/Au nanocomposites have also been synthesized by two-step laser ablation which exhibit modified surface plasmon resonance. The nanocomposites have been tested for photodegradation of Rhodamine B dye. The photodegradation rate is improved significantly in ZnO/Au and marginally in Zn@ZnO/PEG compared to Zn@ZnO nanoparticles due to efficient charge separation and reduced surface defects.