Ag-loaded mesoporous Pb3Nb2O8 photocatalysts with enhanced activity under visible-light irradiation

Abstract

Mesoporous Pb3Nb2O8 photocatalysts were synthesized by the evaporation-induced self-assembly (EISA) method. Ag was deposited on the surface of mesoporous Pb3Nb2O8 by a facile photoreduction process. The as-prepared samples were characterized by TG-DSC, XRD, N2 adsorption, HR-TEM and UV-Vis spectroscopy. The results revealed that mesoporous Pb3Nb2O8 has a large specific surface area and uniform pore size distribution both before and after Ag deposition. The photodegradation of 2-propanol and acetaldehyde gas under visible-light (λ > 420 nm) irradiation was employed to evaluate the photocatalytic activities of the samples. The results showed that the photocatalytic activity of mesoporous Pb3Nb2O8 is greatly improved by the Ag co-catalyst. These mesoporous Pb3Nb2O8 exhibit photocatalytic activities as much as 41 times higher when compared with the Pb3Nb2O8 prepared by the solid state reaction method. The content of loaded Ag ranged from 0.5% to 5% (Ag2SO4). The optimal loading was determined to be 1% corresponding the highest photocatalytic activity. These results clearly indicate that the activity of Pb3Nb2O8 can be improved to obtain an outstanding performance for the photodegradation of organic pollutants.