Synthesis of Cu/ZnO core/shell nanocomposites and their use as efficient photocatalysts

Abstract

The synthesis of a metal/semiconductor (Cu/ZnO) core/shell nanostructure consisting of Cu nanoparticles with an average diameter of 44.4 ± 4.3 nm and coated with a 4.8 ± 0.5 nm-thick layer of ZnO is reported. The Cu/ZnO core/shell nanomaterials were formed by rapidly injecting a mixture of copper(I) chloride, zinc acetate and oleylamine (OLA) solution into a hot OLA solution at 320 °C for 5 min. Both the Cu (core) and ZnO (shell) parts were crystalline according to X-ray diffraction, selected area electron diffraction (SAED), and high-resolution transmission electron microscopy (HRTEM) analyses. The Cu/ZnO core/shell nanomaterials acted as an efficient photocalyst and degraded the pollutant methylene blue, whereas pure Cu nanoparticles did not. The average degradation rate constant of methylene blue by the Cu/ZnO heterostructures was determined to be 1.708 h⁻¹, much higher than those of commercial ZnO (1.628 h⁻¹) and TiO₂ (0.307 h⁻¹), showing that the Cu/ZnO core/shell heterostructure is a promising photocatalyst for pollutant degradation.