Enhanced visible light photocatalytic activity of Cu2+-doped Ag3PO4 nanoparticles

In the present investigation, the optical bandgap of Ag3PO4 nanoparticles is reduced using Cu-doping for an enhanced photocatalytic degradation of Rhodamine-B under visible light. Different Cu (%wt) contents are prepared via a modified sol-gel method. On one hand, structural characterization shows that the as-synthesized CuAg3PO4 nanoparticles crystallize in the known cubic phase in which Ag atoms are substituted with those of Cu. On the other hand, optical properties characterization, supported with density functional theory calculations, indicates that the bandgap energy is narrowed to around 1 eV. The valence band maximum of Ag3PO4, mainly formed by Ag-4d and O-2p orbitals, is now replaced with those of Cu-4d states. In addition, Cu-4d states insertion has converted the previous indirect bandgap (M -> Gamma) to a direct one (Gamma -> Gamma), which is very promising for solar irradiation applications. These findings had a significant impact on the photocatalytic degradation of Cu-doped Ag3PO4 nanoparticles on the Rhodamine-B dye, that showed its best at Cu (0.5 wt%) by increasing the production of hydroxyl and superoxide radicals.

Automated summary

In this study, Cu-doped Ag3PO4 nanoparticles were found to have a reduced optical bandgap, leading to enhanced photocatalytic degradation of Rhodamine-B under visible light. The introduction of Cu changed the crystal structure and optical properties of the nanoparticles, making them promising for solar energy applications.