Prominent roles of Ni(OH)(2) deposited on ZnIn(2)S(4) microspheres in efficient charge separation and photocatalytic H(2) evolution

In this work, Ni(OH)(2)-deposited ZnIn(2)S(4) microspheres (Ni(OH)(2)/ZnIn(2)S(4)) were fabricated using a hydrothermal process, followed by a facile in situ precipitation method. It was demonstrated that the deposition of Ni(OH)(2) on ZnIn(2)S(4) effectively promotes the separation of charges photogenerated over ZnIn(2)S(4), and significantly enhances photocatalytic H(2) evolution. The optimum rate of the photocatalytic H(2) evolution over the 6% Ni(OH)(2)/ZnIn(2)S(4) composite reaches 4.43 mmol g(−1) h(−1), which is 21.1 times higher than that of the pure ZnIn(2)S(4). Based on various characterization results and Au photo-deposition on the composite, it was proposed that the capture of the photogenerated holes by the deposited Ni(OH)(2) would be responsible for the efficient charge separation, which allows more photogenerated electrons to be left on the ZnIn(2)S(4) for the reduction of H(+) to H(2) with a higher rate.