Growth of nano Ag@AgCl on (111) facets of Cu2O microcrystals with an enhanced photocatalytic activity
Abstract
Single crystalline Cu2O nanoparticles were synthesized under mild conditions. A Ag@AgCl/Cu2O photocatalyst was prepared by directly growing Ag@AgCl nanoparticles (NPs) on (111) facets of octahedral Cu2O via a facile precipitation in situ photoreduction method. The results indicate that Ag@AgCl nanoparticles have a narrow size distribution ranging from 10 to 50 nm and are uniformly distributed on the surface of Cu2O nanoparticles. The surface area of the composite reached up to 19.736 m2 g−1. The photocatalytic performance of the Ag@AgCl/Cu2O composite for the degradation of methylene blue (MB) was evaluated under visible light irradiation. The Ag@AgCl/Cu2O composite with 30 wt% Ag@AgCl showed the highest photocatalytic activity, degrading 93.61% MB after 2 h irradiation. The high photocatalytic activity of the Ag@AgCl/Cu2O composite can be attributed to its high surface area, the crystal effect of Cu2O and the surface plasmon resonance of the Ag NPs. In addition, the Ag@AgCl/Cu2O composite can be used as a photocatalyst for the degradation of phenol. Based on these experimental results, a photocatalytic mechanism for the degradation of hazardous chemical effluents over Ag@AgCl/Cu2O photocatalysts was proposed. The free radicals and holes act as the main reactive species during the degradation.