Synthesis of Pt/Zn(OH)2/Cd0.3Zn0.7S for the Photocatalytic Hydrogen Evolution from Aqueous Solutions of Organic and Inorganic Electron Donors Under Visible Light

The work discusses the preparation of multiphase Zn(OH)2/Cd1−xZnxS and Pt/Zn(OH)2/Cd1−xZnxS photocatalysts sensitive to visible light. The synthesized photocatalysts were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and HRTEM techniques. Photocatalytic activity of synthesized samples was investigated in the hydrogen evolution from aqueous solutions of inorganic and organic electron donors, Na2S/Na2SO3 and ethanol, respectively, under the influence of visible light with λ = 450 nm. The photocatalytic hydrogen evolution over said multiphase photocatalysts occurs after some induction period needed for the photocatalyst self-activation. The highest apparent quantum efficiencies achieved at 450 nm for hydrogen evolution from Na2S/Na2SO3 (over 20 % Zn(OH)2/Cd0.3Zn0.7S) and ethanol (over 1 % Pt/10 % Zn(OH)2/Cd0.3Zn0.7S) aqueous solutions were 39 and 6.1 % respectively, appearing to be quite high values for the photocatalytic hydrogen evolution under visible light.