Photoreduction of a Pd-doped mesoporous TiO2 photocatalyst for hydrogen production under visible light

Abstract

Photoreduction with visible light can enhance the photocatalytic activity of TiO2 for the production of hydrogen. In this article, we present a strategy to photoreduce a palladium-doped TiO2 photocatalyst by using near-UV light prior to its utilization. A sol-gel methodology was employed to prepare the photocatalysts with different metal loadings (0.25–5.00 wt% Pd). The structural and morphological characteristics of the synthesized Pd-TiO2 were analyzed by using X-ray Diffraction (XRD), BET Surface Area (SBET), TemperatureProgrammed Reduction (TPR), Chemisorption and X-ray Photoelectron Spectroscopy (XPS). Hydrogen was produced by water splitting under visible light irradiation using ethanol as an organic scavenger. Experiments were developed in the Photo-CREC Water-II (PCW-II) Reactor designed at the CREC-UWO (Chemical Reactor Engineering Centre). It was shown that the mesoporous 0.25 wt% Pd-TiO2 with 2.5 1eV band gap exhibits, under visible light, the best hydrogen production performance, with a 1.58% Quantum Yield being achieved.