Ni2+ and Ti3+ co-doped porous black anatase TiO2 with unprecedented-high visible-light-driven photocatalytic degradation performanceElectronic supplementary information (ESI) available. See DOI: 10.1039/c5ra23743b

• Main Authors: Zhang, Hang, Xing, Zipeng, Zhang, Yan, Li, Zhenzi, Wu, Xiaoyan, Liu, Chuntao, Zhu, Qi, Zhou, Wei
• Format: Journal Article
• Published: 17.12.2015
• ISSN: 2046-2069
• DOI: 10.1039/c5ra23743b

A novel Ni 2+ and Ti 3+ co-doped porous black anatase TiO 2 is successfully synthesized by a facile sol-gel technique combined with an in situ solid-state chemical reduction approach, followed by mild calcinations (350 °C) in argon atmosphere. The obtained photocatalysts are characterized in detail by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, electron paramagnetic resonance, N 2 adsorption, and transmission electron microscopy. The results indicate that the Ni 2+ and Ti 3+ elements are co-doped into the lattice of anatase TiO 2 . The prepared Ni 2+ /Ti 3+ co-doped black anatase TiO 2 possesses a mesoporous structure, consisting of disordered Ti 3+ and oxygen vacancy layers. Based on UV-vis diffuse reflectance spectra and valence band analysis, the doped Ni 2+ and Ti 3+ species can significantly narrow the band gap of anatase TiO 2 due to the formation of mid-gap states, which allows utilization of visible-light and prevents fast recombination of photogenerated charges effectively. Furthermore, the prepared co-doped photocatalysts exhibit unprecedented higher photocatalytic activity than that of the pure TiO 2 and the Ni 2+ doped TiO 2 . The degradation ratio of methyl orange and rhodamine B is up to 95.38 and 95.86%, respectively, within 150 min irradiation of visible-light by the obtained Ni 2+ /Ti 3+ co-doped porous black anatase TiO 2 . The high visible-light photocatalytic degradation performance may be ascribed to the efficient doping of Ni 2+ and Ti 3+ in favor of the absorption of visible-light and the separation of photogenerated charges, and the porous structure facilitating the diffusion of reactants and products. A black Ni doped porous TiO 2 were fabricated via an in situ solid-state chemical reduction approach, which exhibited excellent visible-light-driven performance.