Materials Research Bulletin, Vol.100, 191-197, 2018
Ti3+-TiO2/Ce3+-CeO2 Nanosheet heterojunctions as efficient visible -light-riven photocatalysts
Novel Ti3+-TiO2/Ce3+-CeO2 nanosheet heterojunctions are successfully prepared via a facile hydrothermal approach combined with a wet-chemical deposition precipitation and an in situ solid-state chemical reduction strategy. The structures of the as-prepared samples are characterized in detail by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectroscopy. The results show that Ti3+ and Ce3+ are both doped into the lattice of TiO2 and CeO2, respectively, which narrow the band gap to 2.7 eV and extend the photoresponse to visible light region. The photocatalytic degradation rate of methyl orange and methylene blue are as high as 93.3% and 97.1% under visible-light illumination, respectively. The high degradation rate is attributed to the efficient doping of Ti3+ and Ce3+, formation of surface oxygen vacancy and heterojunction, which favors the absorption of visible light and separation of photogenerated charge carriers.