Exploiting noble-metal-free cocatalysts is of huge interest for photocatalytic water splitting using solar energy. Here we report a composite material consisting of CdS nanocrystals grown on the suface of a nanosized MoS2/graphene hybrid as a high-performance noble-metal-free photocatalyst for H2 evolution under visible light irradiation. Through the optimizing of each component proportion, the MoS2/G-CdS composite showed the highest photocatalytic H2 production activity when the content of the MoS2/graphene cocatalyst is 2.0 wt % and the molar ratio of MoS2 to graphene is 1:2. The photocatalytic H2 evolution activity of the proposed MoS2/G-CdS composite was tested and compared in Na2S-Na2SO3 solution and lactic acid solution. A 1.8 mmol/h H2 evolution rate in lactic acid solution corresponding to an AQE of 28.1% at 420 nm is not only higher than the case in Na2S-Na2SO3 solution of 1.2 mmol/h but also much higher than that of Pt/CdS in lactic acid solution. The relative mechanism has been investigated. It is believed that this kind of MoS2/G-CdS composite would have great potential as a promising photocatalyst with high efficiency and low cost for photocatalytic H2 evolution reaction.

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p-Nitrophenol (PNP) is a difficultly decomposed organic pollutant under solar light in the absence of strong oxidants. This study shows that under artificial solar light PNP can be effectively degraded by a Cu(2)O/TiO(2) p-n junction network which is fabricated by anodizing Cu(0) particles-loaded TiO(2) nanotubes (NTs). The network is composed of p-type Cu(2)O nanowires on the top surface and Cu(2)O nanoparticles on the inner walls of the n-type TiO(2) NT arrays. The Cu(2)O/TiO(2) network shows much higher degradation rate (1.97 μg/min cm(2)) than the unmodified TiO(2) NTs (0.85 μg/min cm(2)). The enhanced photocatalytic acitivity can be attributed to the extended absorption in the visible resulting from the Cu(2)O nanowire networks and the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Cu(2)O/TiO(2) p-n junction interface.

The Co–Ni–B@Ni foam catalyst prepared by a simple electroless plating method exhibits high and stable electrocatalytic activity towards the water splitting.