First observation of visible light photocatalytic activity of carbon modified Nb2O5 nanostructures

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 degrees 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.