Novel visible-light irradiation niobium-doped BiOBr microspheres with enhanced photocatalytic performance

A series of niobium-doped BiOBr (Nb-BiOBr) were successfully synthesized via hydrothermal method. Moreover, the morphology structure and optical property of BiOBr and Nb-BiOBr samples were determined using various characterization techniques including SEM, TEM, EDS, BET, XRD, XPS and DRS, etc. The photocatalytic performance of Nb-BiOBr was deeply investigated with the rhodamine B and ofloxacin degradation under visible-light irradiation as model reaction. The results showed that Nb-BiOBr samples depicted the outstanding photocatalytic performance, especially for the 1.25Nb-BiOBr. Moreover, its reaction kinetic constant was ca. 6.4 times higher than that of undoped BiOBr. The observed photocatalytic performance could be attributed to the strong light absorption, enhanced separation efficiency of charge carriers as well as high specific surface area. Meanwhile, 1.25Nb-BiOBr demonstrated stability in RhB degradation, thereby facilitating the water treatment application.