Facile construction of plasmonic Ag/Nb2O5 films and their photocatalytic activity against organic dye and nanoplastics

To enhance the absorption and utilization of visible light, mitigate the recombination rate of photogenerated electrons and holes, and consequently elevate photocatalytic activity, we synthesized Ag/Nb2O5 films on stainless steel wire mesh via a hybrid approach encompassing hydrothermal, impregnation, and photoreduction methods. These films were thoroughly characterized using advanced techniques such as XRD, SEM, HRTEM, and XPS. The results revealed that Nb2O5 possesses an orthorhombic crystal structure. During photoreduction, Ag+ ions were efficiently converted into Ag-0 nanoparticles, with a diameter of no >20 nm, which were intimately adhered to the Nb2O5 grains, forming a robust composite structure. Light absorption analysis demonstrated that the Ag/Nb2O5 composite films significantly surpassed standalone Nb2O5 films in visible light absorption, accompanied by varying degrees of bandgap narrowing. Additionally, the decrease in PL intensity and the surge in photocurrent density suggest a marked suppression of electron-hole recombination within the Ag/Nb2O5 composites. In photocatalytic RhB degradation tests, the Ag/Nb2O5 composite films exhibited an impressive enhancement in performance, achieving up to 7.1 times higher efficiency compared to pristine Nb2O5 films. Notably, these composite films were also capable of degrading polystyrene (PS) nanoplastics within 120 h, resulting in a notable reduction in the average PS particle size from 375.5 nm to 282.7 nm.