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An efficient Ni 2 P–CdS photocatalyst for photocatalytic hydrogen evolution was synthesized by phosphorizing β-Ni(OH) 2 nanosheet with exposed (001) facets on CdS nanorods. The obtained Ni 2 P–CdS composite displays an outstanding and stable photocatalytic hydrogen generation rate of 68.47 mmol g−1 h−1 in 10 vol% lactic acid under visible light irradiation, more than 17 times higher than that for pure CdS nanorods. The transient photocurrent response, EIS measurement, Mott-Schottky plots, acidic LSV measurement, and PL spectra have proved that Ni 2 P loading can significantly improve the separation of photo-excited electron-hole pairs in CdS nanorods and enhance the hydrogen evolution capability for CdS. These improvements are achieved by features of Ni 2 P such as the high capability of trapping photo-generated electrons from CdS, lifting the total Fermi level and lowering the hydrogen evolution overpotential of the composite. The results show that β-Ni(OH) 2 precursor with a high exposure degree of (001) facet is contributed to the epitaxial formation of (001)-facet-exposed Ni 2 P co-catalyst on CdS nanorods, resulting in that the Fermi level and the hydrogen evolution overpotential of the composite can be further lifted and lowered. This study has provided a novel precursor-derived route to fabricate high-performance co-catalysts with highly exposed active facets on CdS nanorods for effective photocatalytic hydrogen evolution. • Ultrathin β-Ni(OH) 2 nanosheet precursor is employed in fabricating Ni 2 P on CdS. • β-Ni(OH) 2 nanosheet with exposed (001) facet facilitate Ni 2 P(001) growth on CdS. • Hydrogen evolution and charge separation of CdS can be markedly improved by Ni 2 P. [ABSTRACT FROM AUTHOR]

A facile method of loading CoS x nanosheet onto CdS nanorod has been designed, and the prepared CdS-CoS x composite catalyst exhibited significantly improved performance for photocatalytic hydrogen evolution compared with CdS catalyst. This composite catalyst was also used as a photoanode for photoelectrochemical (PEC) hydrogen production. The hydrogen production rate reached 168.6 μmol cm−2 h−1 (37.77 L m−2 h−1) under the simulated solar light, which is 2.7 times that of CdS and the same as that of CdS–Pt. In addition, in the Na 2 S–Na 2 SO 3 system for PEC hydrogen production, an abnormal relationship between photocurrent and the hydrogen production yield was found. By designing a series of experiments, the photocatalytic and photoelectrochemical characteristics for hydrogen production were reasonably revealed for the first time. In this work, the prepared structured catalyst is easy to be recycled, and CoS x can replace precious metal Pt, showing a promising application. Image 1 • CoS x as co-catalyst is loaded on CdS nanorod by a facile method. • CdS-CoS x has good activity and stability for photoelectrochemical (PEC) reaction. • PEC activity of CdS-CoS x as photoanode for H 2 production is the same as that of CdS–Pt. • An abnormal relationship between photocurrent and hydrogen production is found. • The reaction network in Na 2 S–Na 2 SO 3 system for PEC H 2 production is proposed. [ABSTRACT FROM AUTHOR]

In recent years, tremendous efforts have been devoted to develop new photocatalyst with wide spectrum response for H 2 generation from water or aqueous solution. In this work, CdS nanoparticles (NPs) have been immobilized on hydrogenated three-dimensional (3D) branched TiO 2 nanorod arrays, resulting in a highly efficient photocatalyst, i.e, CdS/H-3D-TiO 2 . In addition, electrochemical reduction of H + ion is identified as a limiting step in the photocatalytic generation of H 2 at this catalyst, while here a Pt wired photocatalysis system (CdS/H-3D-TiO 2 /Pt-wire) is designed to overcome this barrier. Without the application of potential bias, visible light photocatalytic hydrogen production rate of CdS/H-3D-TiO 2 /Pt-wire is 18.42 μmol cm −2 h −1 , which is 11.2 times that of CdS/H-3D-TiO 2 without Pt (1.64 μmol cm −2 h −1 ). The Pt wire acts as an electron super highway between the FTO substrate and H + ions to evacuate the generated electrons to H + ions and catalyze the reduction reaction and consequently generate H 2 gas. This work successfully offers a novel direction for dramatic improvement in H 2 generation efficiency in photocatalysis field. [ABSTRACT FROM AUTHOR]