Plasmonic Ag/Ag2O nanoparticles anchored needle-like Bi2O3 as an efficient visible-light-driven nanocomposite photocatalyst

Highlights: • Deposition of plasmonic Ag/Ag₂O NPs on the surface of Bi₂O₃. • Synthesis of Ag/Ag₂O@Bi₂O₃ by thermal-assisted precipitation. • SPR of Ag enhances use of solar energy and transfer of carriers. • Degradation of Reactive Black 5 by CCD model. - Abstract: In this study, a thermal-assisted precipitation method was applied for the uniform deposition of plasmonic Ag/Ag₂O nanoparticles on the surface of needle-like Bi₂O₃ to synthesis Ag/Ag₂O@Bi₂O₃ nanocomposite. The synthesized nanocomposite was characterized by different techniques including UV–vis spectrophotometry, X-ray diffraction (XRD), scanning electronic microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray mapping, and photoluminescence (PL). The visible-light-driven photocatalytic activities of Ag₂O@Bi₂O₃ and Ag/Ag₂O@Bi₂O₃ were evaluated on photo-degradation of Reactive Black 5 (RB 5) dye as model pollutant. The effect of process variables including the initial dye concentration, reaction time, and pH on the photo-degradation of RB 5 was studied by Central Composite Design (CCD) methodology. It was found that the photo-degradation rate of Ag/Ag₂O@Bi₂O₃ was higher than that of the Ag₂O@Bi₂O₃ and Bi₂O₃. The highly efficient photocatalytic activity of Ag/Ag₂O@Bi₂O₃ nanocomposite is mainly ascribed to enhancing photogenerated electron-hole separation and the surface plasmon resonance (SPR) influence of silver-based nanoparticles.