Construction of g-C3N4-mNb2O5 Composites with Enhanced Visible Light Photocatalytic Activity

A series of composites consisting of g-C3N4 sheet and mesoporous Nb2O5 (mNb(2)O(5)) microsphere were fabricated by in situ hydrolysis deposition of NbCl5 onto g-C3N4 sheet followed by solvothermal treatment. The samples were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), N-2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). The photocatalytic activity of the composites was studied by degradation of rhodamine B (RhB) and tetracycline hydrochloride (TC-HCl) in aqueous solution under visible light irradiation (lambda > 420 nm). Compared with g-C3N4 and mNb(2)O(5), g-C3N4-mNb(2)O(5) composites have higher photocatalytic activity due to synergistic effect between g-C3N4 and mNb(2)O(5). Among these composites, 4% g-C3N4-mNb(2)O(5) has the highest efficiency and good recyclability for degradation of both RhB and TC-HCl.