Evaluation of Pd-TiO2/ZSM-5 catalysts composition effects on hydrogen production by photocatalytic water splitting

The photocatalyst composition can significantly affect their physicochemical properties that are directly related to their photocatalytic activity. In this work, the influence of the Pd-TiO2/ZSM-5 catalyst composition on hydrogen production by photocatalytic water splitting was studied. The ZSM-5 zeolite was use as support for the active phase of titanium dioxide; palladium was also incorporated as a metallic co-catalyst. The concentrations of TiO2 and Pd were varied during catalyst synthesis according to a factorial rotational experimental design. The catalysts were characterized and employed in hydrogen production under ultraviolet radiation. Empirical models were obtained for relating physicochemical properties and hydrogen production as functions of palladium and titanium dioxide content. Relative crystallinity of the support and specific surface area were affected only by the titanium dioxide contend while band gap energy and hydrogen production were affected by nominal percentage of metallic co-catalyst and active phase. The most active catalyst was the 1.5%Pd-28%TiO2/ZSM-5, which promoted hydrogen production rate of 1148 μmol gcat−1 h−1 under low power irradiation font.