Enhanced visible light photodegradation of water pollutants over N-, S-doped titanium dioxide and n-titanium dioxide in the presence of inorganic anions

Journal of Saudi Chemical Society

Abdullah M. Asiri¹  Khalid A. Alamry¹  Muhammed S. Al-Amoudi²  Saleh A. Bazaid²  Abdulmajid A. Adam²  Sambandam Anandan³ 

[1] Chemistry Department, Faculty of Science, King Abdul Aziz University, P.O. Box 80203, Jeddah 21413, Saudi Arabia;Chemistry Department, Faculty of Science, Taif University, Taif, Saudi Arabia;Nanomaterials and Solar Energy Conversion Lab, Department of Chemistry, National Institute of Technology, Trichy 620 015, India;

关键词: N-doped TiO2;    S-doped TiO2;    n-TiO2 photocatalytic degradation;    Visible-light;   

DOI  :  10.1016/j.jscs.2011.06.008

来源: DOAJ

【 摘 要 】

The potential application of waste water treatment by photocatalysis is very likely to find its place in the near future. We have studied the photocatalytic degradation of three dyes (Eosin B, Rhodamine 6G, Rhodamine B) in the presence of doped n-TiO2 in water and found that anchoring groups are favorable to the photodegradation of the pollutants. Taking Rhodamine B as a model pollutant, this study points out an alternative route to enhance photodegradation in invisible light, which consumes energy to synthesize, but addition of 0.1 mM of I− or S2O32− increases the discoloration by up to three folds. For example, KI increased degradation to 36% while Na2S2O3 enhanced it by 61%, which was higher than that of pure n-TiO2 after sun light irradiation of 40 min. The enhancement of degradation by I− and S2O32− may be linked to the scavenging of the holes by the inorganic anions, thus inhibiting recombination between h+/e− after excitation of the semiconductor. The degradation is more effective in the presence of S2O32−. In the presence of 0.1 mM KI, the rate constant increased from 0.0231 s−1 to 0.0325 s−1.Peroxodisulphate increases degradation, however, this is attributed to the sulfate radicals.

【 授权许可】

Unknown