Synergetic effect of Ni(OH)2 cocatalyst and CNT for high hydrogen generation on CdS quantum dot sensitized TiO2 photocatalyst

TiO2-Ni(OH)(2)/CNT/CdS hybrid photocatalyst have been fabricated by a facile synthesis method under room temperature. CdS sensitized TiO2 hybrid photocatalysts with Ni(OH)(2) and CNT cocatalysts anchored on TiO2 surface caused significant enhancement in photocatalytic H-2 production rate in lactic acid aqueous solution under visible light irradiation. The optimized TiO2-Ni(OH)(2)/CNT/CdS shows high photocatalytic activity in H-2 genneration of 12 mmol g(-1) h(-1) exceeding TiO2-Ni(OH)(2)/CdS and TiO2/CNT/CdS which can be attributed to the combined effect of Ni(OH)(2) and CNT. Photoluminescence and photo electrochemical characteristics results demonstrated that the introduction of Ni(OH)(2) and CNT displays synergetic effect in promoting the separation efficiency of the photoindliced electron-hole pairs.A scheme of charge transfer over the hybrid photocatalyst is proposed indicating the synergetic effect of Ni(OH)(2) and CNT on promoting electron transport at the heterojunction surface between TiO2 and CdS. The performance of the stability of the TiO2-Ni(OH)(2)/CNT/CdS was tested in the presence of lactic acid under visible light irradiation. The system gives no loss in the hydrogen production after several recycling experiments confirming that the composite is stable and anti-photocorroded. (C) 2016 Elsevier B.V. All rights reserved.