Solvent-free hydrothermal synthesis of anatase TiO2 nanoparticles with enhanced photocatalytic hydrogen production activity

TiO2 nanoparticles exhibiting large surface area were synthesized by the hydrothermal treatment of the water soluble titanium(IV) bis(ammoniumlactato) dihydroxide (TALH) complex in the presence of aqueous ammonia. The obtained powders were characterized by X-ray diffraction, scanning electron microscopy, diffuse reflectance spectroscopy, and nitrogen adsorption. Their photocatalytic activities were assessed by the photocatalytic hydrogen evolution from aqueous EDTA solutions. The effects of Pt- and photocatalyst loading, EDTA concentration, light intensity, pH, and temperature on the H-2 evolution rate were studied in detail. The highest reaction rate was obtained for the TiO2 photocatalyst loaded with 0.4-0.5 wt.% Pt at pH 5 and this was found to be 18 and 34% higher than that of TiO2 P25 and TiO2 UV100, respectively. The reaction rate increased substantially with increasing the temperature from 5 degrees C to 45 degrees C. (C) 2013 Elsevier B.V. All rights reserved.