The study on properties of CdS photocatalyst with different ratios of zinc-blende and wurtzite structure

Abstract

The mixtures of zinc blende and wurtzite CdS nanoparticles were prepared via a solvothermal method by controlling the precursor ratio (Cd/S molar ratio). The as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and ultraviolet-visible (UV-vis) spectroscopy. These results demonstrate that not only the morphology but also the phase composition of CdS nanostructures was sensitively altered by the precursor ratio (Cd/S molar ratio). Photocatalysis test results show that the photocatalytic activity was mainly dependent on the ratio between zinc blende and wurtzite phases in CdS samples. The product prepared with 1 : 2 Cd/S molar ratio exhibited higher photocatalytic activities in comparison with products prepared with other Cd/S molar ratios, which can be attributed to the improved charge separation at the zinc blende/wurtzite junction interface.