Novel photocatalysts based on Cd1-xZnxS/Zn(OH)(2) for the hydrogen evolution from water solutions of ethanol

Multiphase photocatalysts Pt/Cd1-xZnxS/ZnO/Zn(OH)(2), Pt/Cd1-xZnxS/ZnO, and Pt/ Cd1-xZnxS/Zn(OH)(2) were synthesized by a new two-step technique. The photocatalysts were characterized by a wide range of experimental techniques: X-ray diffraction, high-resolution transmission electron microscopy combined with energy-dispersive X-ray spectroscopy, low-temperature N-2 adsorption/desorption, and UV/VIS spectroscopy. The photocatalytic activity was tested in a batch reactor in the reaction of H-2 evolution from aqueous solutions of ethanol under visible light irradiation (lambda > 420 nm). The highest achieved photocatalytic activity was 2256 mu mol H-2 per gram of photocatalyst per hour; the highest quantum efficiency was 10.4%. The activity of Pt/Cd1-xZnxS/Zn(OH)(2) was higher than that of Pt/Cd1-xZnxS/ZnO/Zn(OH)(2) and Pt/Cd1-xZnxS/ZnO. The explanation of enhanced activity of zinc cadmium sulfide/e-zinc hydroxide based on quantum calculations was suggested. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.