Effect of Ni(OH)2 on CdS@g-C3N4 Composite for Efficient Photocatalytic Hydrogen Production

The composites of CdS@g-C3N4/Ni(OH)2 was prepared by photo-deposition method. The co-catalyst Ni2+/Ni clusters reduced from Ni(OH)2 can provide active sites on the surface of CdS@g-C3N4, which significantly accelerate the separation of electron–hole pairs though the special channel formed between CdS and g-C3N4. This way further improved the H2 production activity for 1445.5 µmol, which was 39.5 times and 149.0 times then pure CdS and g-C3N4, respectively. The AQE corresponding to the produced H2 was 5.59%. The morphology, crystal structure and chemical valence of the elements were characterized by SEM, HRTEM, XRD, XPS, UV–Vis, etc. The photoelectrochemical properties of CdS@g-C3N4/Ni(OH)2 was measured by steady-state fluorescence and electrochemical. The results show that composite catalyst posses a high photoelectric density and well light absorption properties. the purpose of high H2 production and fleet charges separation is achieved. Simultaneously, the reaction of H2 production mechanism was proposed under the condition of lactic acid solution as a sacrificial reagent.