Flash‐photoreduction method to enhance hydrogen photogeneration on Pd@TiO₂

Abstract

A novel method for the preparation of highly dispersed Pd nanoparticles on TiO 2 (P25) was proposed based on ultraviolet irradiation over a converging strip of the solution passing through a quartz reactor, which leads to a flash photoreduction. The high-resolution transmission electron microscopy (HRTEM) results clearly indicated that the flash type irradiation reduced the Pd particle size to less than 9 nm and shifted the absorption edge of bare TiO 2 from 3.25 to below 3.0 eV after Pd loading without any change in structural and lattice parameters of the support. The narrow size distribution of Pd particles and their single crystalline feature are endorsed by X-ray powder diffraction, CO chemisorption, HRTEM, and CO-Fourier-transform infrared spectroscopy methods. Increasing the rate of H 2 photogeneration to 868 μmolÁg −1 Áhr −1 is the result of the developed method for the Pd loading on TiO 2 .