First observation of visible light photocatalytic activity of carbon modified Nb2O5nanostructures

Abstract

Carbon-modified niobium oxide (Nb₂O₅) nanostructures, that firstly exhibited good visible light photocatalytic activity of Nb₂O₅ species, were synthesized by utilizing a low temperature, one-pot nonaqueous sol–gel approach. The resulting products were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption. Unlike the commercial or other reported Nb₂O₅ products that only respond to the UV-light irradiation, the present carbon-modified Nb₂O₅ nanostructures obtained at 200 °C in our experiment exhibited much better photocatalytic activity on degradation of RhB under visible light, which was about 39 times of that of commercial Nb₂O₅, 18 times of that of Degussa P25, and 5 times of that of carbon modified mesoporous TiO₂. Moreover, these carbon-modified Nb₂O₅ nanostructures were also able to efficiently split water under visible light. The growth mechanism and the origin of visible light photocatalytic activity of the resulting Nb₂O₅ nanostructures were proposed. These carbon-modified Nb₂O₅ products are expected to be more suitable candidates than that of the most studied TiO₂ as visible light photocatalysts.