Photocatalytic degradation of aqueous Methyl Orange using nitrogen-doped TiO 2 photocatalyst prepared by novel method of ultraviolet-assisted thermal synthesis

• Published in: Journal of environmental sciences (China) Vol. 66; pp. 81 - 93
• Main Authors: Nasirian, Mohsen, Mehrvar, Mehrab
• Format: Journal Article
• Language: English
• Published: Netherlands 01.04.2018
• Subjects: Advanced oxidation processes; Ultraviolet-assisted thermal synthesis; N–TiO; Photocatalysis
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/j.jes.2017.05.032

A nitrogen-doped titanium dioxide composite photocatalyst (N-TiO ) with heterojunction structures is synthesized by three different approaches: a novel UV-assisted thermal synthesis, annealing, and microwave technique. Photocatalytic activities of synthesized photocatalysts are evaluated by the degradation of Methyl Orange under ultraviolet light types A (UV-A), B (UV-B), and C (UV-C), visible light, and direct sunlight irradiation. Results show that by using N-TiO photocatalyst prepared by the UV-assisted thermal synthesis and annealing, the degradation increases by 16.5% and 20.4%, respectively, compared to that by bare TiO . The best results are obtained at a nitrogen to TiO mass ratio of 0.15 (N:TiO ). The enhancement of the photocatalytic activity observed in the visible range is mainly attributed to the increasing separation rate of photogenerated charge carriers. The novel UV-assisted thermal synthesis has produced encouraging results as a preparation method for the nitrogen-doped TiO photocatalyst; thus, further studies are recommended for process optimization, immobilization, and scale-up to evaluate its applicability in wastewater treatment.