Perylenetetracarboxylic diimide modified Zn0.7Cd0.3S hybrid photocatalyst for efficient hydrogen production from water under visible light irradiation

A hybrid photocatalyst of Zna(0.7)Cd(0.3)S and perylenetetracarboxylic diimide (PDI) was prepared with a facile co-precipitation-hydrothermal method. The structure and morphology of Zn0.7Cd0.3S/PDI photocatalyst was investigated systematically by X-ray diffraction experiments (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), and scan electron microscopy (SEM), etc. The H-2 production rate of Zn0.7Cd0.3S/PDI is 5.166 mmol h(-1) g(-1) in the aqueous solution of sacrificial reagents Na2SO3 and Na2S, which is 6.5 times of that of pure Zna(2)Cdo(3)S solid solution without PDI modification. The corresponding apparent quantum efficiency (QE) of Zn0.7Cd0.3S/PDI nanocomposite is 22.5% under monochromatic light irradiation at 420 nm, which is also significantly higher than that of pure Zn0.7Cd0.3S solid solution (3.35%). Comparing to Zn0.2Cd0.3S solid solution, higher transient photocurrent is measured for the Zn0.7Cd0.3S/PDI nanocomposite. This result indicates that PDI can collect the photogenerated electrons in Zn0.2Cd0.3S, thereby inhibiting the photogenerated electron-hole pair recombination of Zn0.7Cd0.3S/PDI nanocomposite. This Zn0.7Cd0.3S/PDI hybrid catalyst suggests that organic semiconductor modification is a useful way for enhancing the photocatalytic performance of ZnxCd1-xS. (C) 2018 Elsevier B.V. All rights reserved.