Structural and photocatalytic properties of Cd1-xZnxS nanocrystals via organic solution method

Abstract

Uniform CdxZn[Formula: see text]S nanocrystals with size between 4[Formula: see text]nm and 9[Formula: see text]nm were fabricated by an organic chemical method. The structural, morphology as well as optical properties of the samples were investigated by X-ray diffraction (XRD), TEM, and UV–Vis absorbance techniques. The XRD patterns of CdxZn[Formula: see text]S nanocrystals indicated that the solid solution possesses cubic zinc-blende structure. By tuning the composition of Zn ions in the alloy, the band gap of CdxZn[Formula: see text]S can be modulated from 2.10[Formula: see text]eV to 3.17[Formula: see text]eV. Photocatalytic hydrogen evolution was investigated under visible-light ([Formula: see text][Formula: see text]nm) irradiation with Na2S/Na2SO3 as the electron donor. It is found that Cd[Formula: see text]Zn[Formula: see text]S nanocrystals have the highest photoactivity with a H2 evolution rate of 1.52[Formula: see text]mmol/h[Formula: see text][Formula: see text][Formula: see text]g. The CdxZn[Formula: see text]S nanoparticles exhibit stable activity in a cycled hydrogen evolution experiment.