N-doped P25 TiO{sub 2}-amorphous Al{sub 2}O{sub 3} composites: One-step solution combustion preparation and enhanced visible-light photocatalytic activity Li, Fa-tang [College of Science, Hebei University of Science and Technology, Shijiazhuang 050018 (China)]; Hebei Key Laboratory of Material Near-Net Forming Technology, Hebei University of Science and Technology, Shijiazhuang 050018 (China)]; Zhao, Ye; Hao, Ying-juan; Wang, Xiao-jing; Liu, Rui-hong; Zhao, Di-shun [College of Science, Hebei University of Science and Technology, Shijiazhuang 050018 (China)]; Chen, Dai-mei [National Laboratory of Mineral Materials, China University of Geosciences, Beijing 100083 (China)] 36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; ALUMINIUM OXIDES; DOPED MATERIALS; EFFICIENCY; ELECTRONIC STRUCTURE; IRRADIATION; NITROGEN; PHOTOCATALYSIS; PHOTOLUMINESCENCE; SCANNING ELECTRON MICROSCOPY; SPECIFIC SURFACE AREA; SURFACES; TITANIUM OXIDES; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY Graphical abstract: N-doped P25 TiO{sub 2}-amorphous Al{sub 2}O{sub 3} composites were facile prepared via one-step solution combustion, which showed much higher visible-light photocatalytic activity than that of P25 TiO{sub 2} due to the N-doping in the high temperature combustion process, synergetic effect between amorphous Al{sub 2}O{sub 3} and TiO{sub 2}, and high specific surface area. Highlights: Black-Right-Pointing-Pointer N-doped P25 TiO{sub 2}-amorphous Al{sub 2}O{sub 3} composites were prepared via solution combustion. Black-Right-Pointing-Pointer The composites showed much higher visible light activity than that of P25 TiO{sub 2}. Black-Right-Pointing-Pointer Amorphous Al{sub 2}O{sub 3} was firstly found to be a photocatalyst under UV light illumination. Black-Right-Pointing-Pointer Probable photocatalytic mechanism under visible light irradiation was proposed. - Abstract: Nitrogen-doped Degussa P25 TiO{sub 2}-amorphous Al{sub 2}O{sub 3} composites were prepared via facile solution combustion. The composites were characterised using X-ray diffraction, high-resolution transmission microscopy, scanning electron microscopy, nitrogen adsorption-desorption measurements, X-ray photoelectron spectroscopy, UV-vis light-diffusion reflectance spectrometry (DRS), zeta-potential measurements, and photoluminescence spectroscopy. The DRS results showed that TiO{sub 2} and amorphous Al{sub 2}O{sub 3} exhibited absorption in the UV region. However, the Al{sub 2}O{sub 3}/TiO{sub 2} composite exhibited visible-light absorption, which was attributed to N-doping during high-temperature combustion and to alterations in the electronic structure of Ti species induced by the addition of Al. The optimal molar ratio of TiO{sub 2} to Al{sub 2}O{sub 3} was 1.5:1, and this composite exhibited a large specific surface area of 152 m{sup 2}/g, surface positive charges, and enhanced photocatalytic activity. These characteristics enhanced the degradation rate of anionic methylene orange, which was 43.6 times greater than that of pure P25 TiO{sub 2}. The high visible-light photocatalytic activity was attributed to synthetic effects between amorphous Al{sub 2}O{sub 3} and TiO{sub 2}, low recombination efficiency of photo-excited electrons and holes, N-doping, and a large specific surface area. Experiments that involved radical scavengers indicated that {center_dot}OH and O{sub 2}{center_dot}{sup -} were the main reactive species. A potential photocatalytic mechanism was also proposed. Available from http://dx.doi.org/10.1016/j.jhazmat.2012.08.016 Netherlands 2012-11-15 English Journal Article Journal Name: Journal of Hazardous Materials; Journal Volume: 239-240; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA) Medium: X; Size: page(s) 118-127 https://doi.org/10.1016/J.JHAZMAT.2012.08.016 PII: S0304-3894(12)00822-9 [] 239-240 Journal ID: ISSN 0304-3894; CODEN: JHMAD9; Other: PII: S0304-3894(12)00822-9; TRN: NL13R2608116225 NLN 2013-12-02 22161793