Preparation and Visible Light Responsive Photocatalytic Activity of Nitrogen-doped Bi2O3 Photocatalyst

Bi2O3 photocatalysts doped with different amounts of nitrogen were synthesized by a precipitation method using bismuth nitrate and hexamethylenetetramine as precursors. The as-synthesized samples were characterized and analyzed by XRD, FT-ER, XPS, UV-Vis and PL. The results indicate that the undoped Bi2O3 displays a single monoclinic phase. While the N-doped Bi2O3 samples are mixed crystals, which were composed of tetragonal beta-Bi2O3 and Bi5O7NO3 phases. The oxygen in the lattice of Bi2O3 is partially substituted by nitrogen atom, existed stably in the form of Bi-N bond. Meanwhile, nitrogen dopant promotes the formation of beta-Bi2O3 phase. Compared with undoped Bi2O3, the light absorption property of N-doped Bi2O3 has apparently extended into visible light region and the fluorescence intensity decreases evidently. Furthermore, the photodegradation performance of methyl orange shows that N-doped Bi2O3 samples have excellent visible light photocatalytic activity.