Synthesis, characterization of Cu, N co-doped TiO2 microspheres with enhanced photocatalytic activities

Abstract

The mesoporous Copper, nitrogen co-doped TiO2 microspheres was prepared via solvothermal approach, followed by nitriding treatment under an ammonia gas flow. The crystalline structures of the as-prepared catalyst and the chemical compositions of Cu,N co-doped TiO2 were determined using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) respectively. The photocatalytic activity of the as-prepared sample was investigated by monitoring the degradation of Rhodamine-B under visible light irradiation. Experimental results indicated that mesoporous Cu,N co-doped TiO2 microspheres showed higher photocatalytic activity than Cu-TiO2 microspheres and anatase TiO2 under visible light irradiation. The higher photocatalytic activity of the mesoporous Cu,N co-doped TiO2 microspheres sample could be attributed to the synergistic effects of large BET surface area, extended light absorption, efficient charge separation which was stabilized by the presence of oxygen vacancies. It was discovered that, valence states maintain stability after nitriding treatment. The sample synthesized from 0.1% molar quantity of Cu dopant, and nitrided at 400°C for 30 min gave the highest photocatalytic activity. Correspondence to: Minghui Yang, Ningbo Institute of Industrial Technology, Chinese Academy of Sciences, No. 1219 Zhongguan West Road, Zhenhai District, Ningbo, 315201 China, Tel/Fax: +86-411-85168242, E-mail: myang@nimte.ac.cn