TiO2ZnO photocatalysts synthesized by sol–gel auto-ignition technique for hydrogen production

Abstract The present work investigates Zn doped TiO 2 (1.0, 5.0, 10.0, 12.0 and 30.0 wt.% Zn) photo-catalysts; prepared by sol–gel auto-ignition method, which were systematically investigated to configure their structural, surface, optical and morphological properties via using X-ray diffractometer (XRD), Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared spectrometer (FTIR), and UV–Vis spectrophotometer. The photocatalytic H 2 evolution using the TiO 2 ZnO suspensions was evaluated in a 25 vol.% aqueous ethanol medium using UV illumination (Hg lamp λ = 254 nm, 2.2 mW/cm 2 ). The Zn +2 concentrations utilized to prepare TiO 2 ZnO nanocomposites were found to have significant effects on specific surface areas, energy band gaps (E g ), efficient separation of charged pairs and thus affected the photocatalytic performances. The photocatalytic activity of the TiO 2 –10 wt.% ZnO composite has reached an optimal H 2 production of 1048 μmol h −1 exceeding those of the pure TiO 2 (151 μmol h −1 ) and TiO 2 P25 (595 μmol h −1 ) photocatalysts.