Electrochemical-assisted photodegradation of dye on TiO2 thin films: Investigation on the effect of operational parameters

Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.
Journal of Hazardous Materials (Impact Factor: 4.53). 03/2005; 118(1-3):197-203. DOI: 10.1016/j.jhazmat.2004.11.009
Source: PubMed


Electrochemical-assisted photodegradation of methyl orange has been investigated using TiO2 thin films. The films were prepared by sol-gel dip-coating method. Several operational parameters to achieve optimum efficiency of this electrochemical-assisted photodegradation system have been tested. Photoelectrochemical degradation was studied using different light sources and light intensity. The light sources chosen ranged from ultraviolet to visible light. The effect of agitation of the solution at different speeds has also been studied. Slight improvement of photodegradation rate was observed by applying higher agitation speed. Investigation on the electrode after repeated usages show the electrode can be reused up to 20 times with percentage of deficiency less than 15%. The study on the effect of solution temperature indicated that the activation energy of the methyl orange degradation is 18.63 kJ mol(-1).

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    • "Therefore, the efficiency of PEC degradation of pollutants could be enhanced. Most of the previous publications on the degradation of organic compounds have mainly focused on the optimization of photoreaction conditions and the examination of the primary process by monitoring decolorization [30] [31]. Less attention has been devoted to investigations on the degradation pathway of organic compounds . "
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    • "Along with the evaporation of the solvent, wedge shaped film is formed on the surface of substrate. A lot of researchers have used sol-gel dip-coating method to study the application of the photocatalytic TiO 2 (Dongare et al., 2003; Lee et al., 2004; Zainal et al., 2005). "

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