Photocatalytic Hydrogen Production from Glycerol Aqueous Solution Using Cu-Doped ZnO under Visible Light Irradiation

Cu-doped ZnO photocatalysts at different Cu loadings were prepared by a precipitation method. The presence of Cu in the ZnO crystal lattice led to significant enhancement in photocatalytic activity for H2 production from an aqueous glycerol solution under visible light irradiation. The best Cu loading was found to be 1.08 mol %, which allowed achieving hydrogen production equal to 2600 μmol/L with an aqueous glycerol solution at 5 wt % initial concentration, the photocatalyst dosage equal to 1.5 g/L, and at the spontaneous pH of the solution (pH = 6). The hydrogen production rate was increased to about 4770 μmol/L by increasing the initial glycerol concentration up to 10 wt %. The obtained results evidenced that the optimized Cu-doped ZnO could be considered a suitable visible-light-active photocatalyst to be used in photocatalytic hydrogen production without the presence of noble metals in sample formulation.