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 /Cd 1−x Zn x S and Pt/Zn(OH) 2 /Cd 1−x Zn x S 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, Na 2 S/Na 2 SO 3 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 Na 2 S/Na 2 SO 3 (over 20 % Zn(OH) 2 /Cd 0.3 Zn 0.7 S) and ethanol (over 1 % Pt/10 % Zn(OH) 2 /Cd 0.3 Zn 0.7 S) aqueous solutions were 39 and 6.1 % respectively, appearing to be quite high values for the photocatalytic hydrogen evolution under visible light.