Silver doping on TiO 2 nanoparticles using a sacrificial acid and its photocatalytic performance under medium pressure mercury UV lamp

Abstract

Titanium dioxide nanoparticles were modified using a sacrificial organic acid carrier at low pH values where the zeta potential of the TiO 2 nanoparticles was found to be highly effective forming 0.05, 0.1, 0.5 wt.% Ag/TiO 2 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 °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/TiO 2 nanocomposite has the best photocatalytic activity compared with other synthesized nanocomposites and that of the non-modified TiO 2 (P25). Further calcination of the synthesized nanocomposites has shown to be effective in lower Ag concentrations where 0.1 wt.% Ag/TiO 2 nanocomposite has the best photocatalytic activity at the 400 °C.