Formic acid dehydrogenation catalyzed by bimetallic nanoalloys supported by monodisperse-porous microspheres: Catalytic and visible light driven photocatalytic hydrogen generation

Abstract

PdAu nanoparticle decorated, monodisperse-porous SiO2, TiO2 and CeO2 microspheres (MSs) synthesized by polymerization induced colloid aggregation (PICA) and staged hydrothermal methods were evaluated as catalysts for hydrogen production via formic acid (FA) dehydrogenation. In FA dehydrogenations performed at 60 °C, the highest rate with the TOF of 3170 h−1 was obtained using PdAu@SiO2 MSs with the highest specific surface area (214.4 m2/g). PdAu@TiO2 and PdAu@CeO2 MSs were evaluated as photocatalyts for visible and UV light driven FA dehydrogenations at room temperature for the first time. The highest TOF was obtained as 1391 h−1 with PdAu@TiO2 MSs in visible light driven FA dehydrogenation, which was pretty higher with respect to the similar catalysts previously used at room temperature. 6.2 times higher hydrogen production rate was obtained with PdAu@TiO2 MSs under visible light with respect to monometallic Pd@TiO2 MSs used in dark due to alloy formation and visible light irradiation.