Investigation of ZnO@CdS nanocomposite with amplified photocatalytic H2 production under visible light irradiation

Abstract

Researchers are trying to develop an efficient solar-powered catalytic water splitting system to solve the energy dilemma and generate green hydrogen. In this study, ZnO@CdS nano-heterostructures were synthesized using sol-gel and co-precipitation techniques. The pristine ZnO, CdS, and their heterostructures were characterized through various characterization tools such as XRD, SAED, XPS, FTIR, EDX, SEM, FE-TEM, UV–vis, Mott-Schottky, GCG, EIS, and PL, to know the crystal structure, chemical state, elemental composition, morphology, band gap, scheme mechanism, hydrogen production and charge transfer resistance characteristics of the samples, respectively. The SEM, FE-TEM, confirm that CdS NPs are well decorated on hexagonal ZnO rods. The efficient H2 production of 587.86 μmolg−1 h−1 were measured for the optimized sample which is 3.91 times greater than pure ZnO rods and 3.22 times than CdS NPs. Strong photo-cyclic stability test was carried out for 20 h in four cycles while, PL spectroscopy confirms the suppressed charge recombination. All of the above characterization prove that (ZC-20) optimized sample, has a potential to be used as an efficient and stable photocatalyst for H2 production via photocatalytic water splitting.