We report the synthesis of highly active NiS/CdS photocatalysts via a simple hydrothermal loading method for H(2) evolution from lactic acid sacrificial solution under visible light. In the absence of noble metals, a high quantum efficiency of 51.3% was measured at 420 nm.

To construct photocatalytically active MOFs, various strategies have recently been developed. We have synthesized and characterized a new metal-organic framework (MOF-253-Pt) material through immobilizing a platinum complex in 2,2 0 -bipyridine-based microporous MOF (MOF-253) using a post-synthesis modification strategy.The functionalized MOF-253-Pt serves both as a photosensitizer and a photocatalyst for hydrogen evolution under visible-light irradiation. The photocatalytic activity of MOF-253-Pt is approximately five times higher than that of the corresponding complex. The presence of the short Pt/Pt interactions in the framework was revealed with extended X-ray absorption fine structure (EXAFS) spectroscopy and low temperature luminescence. These interactions play an important role in improving the photocatalytic activity of the resulting MOF.

One‐dimensional (1D) hierarchical structures composed of Ni3S2 nanosheets grown on carbon nanotube (CNT) backbone (denoted as CNT@Ni3S2) are fabricated by a rational multi‐step transformation route. The first step involves coating the CNT backbone with a layer of silica to form CNT@SiO2, which serves as the substrate for the growth of nickel silicate (NiSilicate) nanosheets in the second step to form CNT@SiO2@NiSilicate core‐double shell 1D structures. Finally the as‐formed CNT@SiO2@NiSilicate 1D structures are converted into CNT‐supported Ni3S2 nanosheets via hydrothermal treatment in the presence of Na2S. Simultaneously the intermediate silica layer is eliminated during the hydrothermal treatment, leading to the formation of CNT@Ni3S2 nanostructures. Because of the unique hybrid nano‐architecture, the as‐prepared 1D hierarchical structure is shown to exhibit excellent performance in both supercapacitors and photocatalytic H2 production.

A NiS/C3 N4 photocatalyst containing earth-abundant elements only was constructed by means of a simple hydrothermal method. This photocatalyst shows efficient hydrogen evolution (48.2 μmol h(-1) ) under visible light when using triethanolamine as a sacrificial reagent. The optimal loading of 1.1 wt % NiS on C3 N4 as a cocatalyst can enhance the H2 production by about 250 times compared with the native C3 N4 . The highest apparent quantum efficiency of 1.9 % was recorded at 440 nm.

Pt is one of the most effective cocatalysts used in hydrogen evolution photocatalysts in water splitting. However, because Pt is an expensive noble metal, the efficient and optimum use of Pt is of high importance. In this work, the effect of loading conditions for Pt nanoparticles on the surface of CdS as a model photoabsorber was studied to reveal the important parameters for obtaining Pt cocatalyst of high activity. The activities of as-prepared Pt/CdS samples were evaluated in H2 evolution from photocatalytic water splitting using Na2S and Na2SO3 as sacrificial reagents. It was found that the solution environment during Pt photoreduction played a critical role. Pt/CdS photocatalyst with Pt reduced in NaOH alkaline solution exhibited a markedly higher H2 evolution activity (∼1300 μmol h–1) than samples obtained in acidic or neutral solution (<50 μmol h–1). Further materials characterization revealed that, in alkaline solution, Pt4+ species in the precursor (H2PtCl6·xH2O) can be well reduced to metallic Pt0, which shows high hydrogen evolution activity. On the other hand, in acidic or neutral solution, Pt4+ species can be only partially reduced to Pt2+ species, which are deposited on the surface of CdS. It is suggested that the promotional effect of alkaline conditions on Pt reduction is attributable to enhanced hydrolysis of PtCl6 2– to species containing fewer Cl– ions, such as Pt(OH)5Cl2– and Pt(OH)6 2–, which are then more easily reduced.