N-doped P25 TiO2-amorphous Al2O3 composites: One-step solution combustion preparation and enhanced visible-light photocatalytic activity

► N-doped P25 TiO2-amorphous Al2O3 composites were prepared via solution combustion. ► The composites showed much higher visible light activity than that of P25 TiO2. ► Amorphous Al2O3 was firstly found to be a photocatalyst under UV light illumination. ► Probable photocatalytic mechanism under visible light irradiation was proposed.