Silver doping on TiO2 nanoparticles using a sacrificial acid and its photocatalytic performance under medium pressure mercury UV lamp

Titanium dioxide nanoparticles were modified using a sacrificial organic acid carrier at low pH values where the zeta potential of the TiO2 nanoparticles was found to be highly effective forming 0.05, 0.1, 0.5 wt.% Ag/TiO2 nanocomposites. The organic carrier was acting both as an Ag ion carrier and a hole scavenger enhancing the photodeposition of Ag atoms. The formed nanocomposites were calcined at 300 and 400 degrees C under controlled atmosphere and later examined for photocatalytic performance using a 125 medium pressure mercury lamp decomposing formic acid as an organic pollutant. Morphological, crystallographical and UV-vis spectroscopy analyses were used to characterize the synthesized nanocomposites. The studies have revealed that non-calcined 0.5 wt.% Ag/TiO2 nanocomposite has the best photocatalytic activity compared with other synthesized nanocomposites and that of the non-modified TiO2 (P25). Further calcination of the synthesized nanocomposites has shown to be effective in lower Ag concentrations where 0.1 wt.% Ag/TiO2 nanocomposite has the best photocatalytic activity at the 400 degrees C. (C) 2009 Elsevier B. V. All rights reserved.