Facile Synthesis of Cu Doped Au–ZnS Photocatalyst

In this work, we report on the synthesis of of Cu-doped Au–ZnS nanoparticles (Au–Zn1−xCuxS; where x = 0.00, 0.1 and 1%) using a one-pot chemical method that makes use of 1,3-propanediol as a solvent, a reducting agent and a stabilizing layer. The structure and morphology of the as prepared nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectrometry (EDX). Optical extinction measurements showed that the Cu-doped Au–ZnS nanoparticles exhibit a localized surface plasmon resonance (SPR) clearly red-shifted with respect to that of bare Au nanoparticles (AuNPs). In addition, it was found that the optical band gaps of Cu-doped ZnS nanocrystals blue-shifted (i.e., the band gap widening) to shorter wavelength compared to pure ZnS nanocrystals. Photocatalytic activities of Cu-doped Au–ZnS nanocomposites were evaluated by the degradation of 4-Nitrophenol under illumination by solar light. Enhanced performances compared either to undoped Au–ZnS nanocomposites were observed. The effect of various parameters was investigated on the photocatalytic activities of Cu-doped Au–ZnS nanocomposites.