High photocatalytic activity of Ag/Ag₃PO₄:W heterostructure formed by femtosecond laser irradiation

In this work, the W-doped Ag₃PO₄ was prepared by the chemical coprecipitation method and irradiated with a femtosecond laser (FL). The successful formation of the Ag/Ag₃PO₄:W heterostructure was confirmed by XRD analysis. A higher structural disorder in the [PO₄] clusters was observed for the FL irradiated sample (Ag₃PO₄:W-FL), indicating the formation of Ag metallic from the Ag₃PO₄ structure. The photocatalytic activity of the samples was studied by photodegradation of rhodamine B under visible light irradiation. The formation of Ag nanoparticles on the surface of Ag₃PO₄:W led to a degradation rate constant 3.54 times higher than the nonirradiated sample. This higher photocatalytic activity was related to the surface plasmon resonance effect of the Ag metallic, which acts by capturing photoexcited electrons from the Ag₃PO₄:W, avoiding the recombination of electron-hole pairs, and thus improving the photocatalytic activity. (author)