Enhancement in the photocatalytic activity of Ag loaded N-doped TiO2 nanocomposite under sunlight

A N-doped titania–silver nanocomposites have been prepared by simple microwave assisted and impregnation–reduction method for the first time. As synthesized nanocomposites with different Ag contents were characterized for their phase purity, morphology, particle size, optical properties and elemental composition. It is found that N-doped TiO2 silver nanocomposites are pure in anatase phase with an average crystallite size of 10 nm. The catalyst was tested for dye degradation and photodegradation efficiency was found to be 99.6 and 88.7 % within 90 min under UV and sunlight respectively. A 40 % enhancement in the photodegradation efficiency was achieved by Ag loading in comparison with the N-TiO2 under sunlight. The fluorescence quenching of Ag loaded N-TiO2 indicates decrease in rate of electron–hole pair recombination that enhances photocatalytic performance. The effects of photocatalytic operational parameters such as method of surface modification, catalyst loading and irradiation sources on the photodegradation of methyl orange were also investigated.