Investigation on the photocatalytic performance of Ag4P2O7 microcrystals for the degradation of organic pollutants

The silver-based metal oxides have been considered good photocatalysts for the removal of organic dyes in wastewater treatments. In our knowledge, for the first time, the photoluminescence and photocatalytic properties of silver pyrophosphate (Ag4P2O7) synthesized by the precipitation method have been investigated. The long- and short-range structural ordering was analyzed by means of X-ray diffraction and, Raman and infrared spectroscopies, respectively. The broadband photoluminescence spectrum revealed a typical profile arising from electronic transitions involving intermediary energy levels in the band gap. The photocatalytic efficiency of Ag4P2O7 was monitored for the degradation of rhodamine B and 6G under ultraviolet light irradiation. The reusability and stability of this material as photocatalyst were checked by recycling tests. Different radical scavengers were introduced into reaction medium to detect the main active species involved in the degradation process of rhodamine 6G. Based on our results, a photodegradation mechanism for this synthetic organic dye by using Ag4P2O7 photocatalyst was proposed in detail.