Electrochemical oxidation depends enormously on the electrode materials used during electrolysis. Dimensionally Stable Anodes (DSA) represent a good option for electrochemical oxidation applied to wastewater treatment due to the ability of generating hydroxyl radicals. These radicals are strong, non-selective oxidizing agents, which are able to react with organic pollutants and mineralize them. However, this kind of electrodes is commonly synthesized from chloride precursors, which represents an environmental problem, because they can form undesirable chlorinated by-products during the electrolysis. Some DSA electrodes such as PbO₂, SnO₂-Sb₂O₅ and TiO₂ are promising anodes due to their high over-potential for oxygen evolution, which leads to the ability of OH radical production; however, their main drawback is the low chemical stability [1, 2]. This disadvantage prevents their use in environmental applications and causes the search for other materials with better properties. In this work we present the synthesis as well as its electrochemical application of a DSA electrode composed of Ti|IrO₂-SnO₂-Sb₂O₃. The purpose is enhancing the chemical stability and prolonging the electrode lifetime. The Pechini concept was used to this material, but with the advantage that no chloride precursors were employed [3]. Cyclic voltammetry (CV), X-ray diffraction (DRX), Energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) were used to characterize the as-prepared electrode. The electrocatalytic properties were evaluated by electrochemical degradation of tartrazine in aqueous media as well as dibenzothiophene in organic media. Results showed that noncracked oxide layers were obtained and that the electrode has a great capability for the electrochemical degradation of both molecules.

Keywords: DSA electrode, Ti|IrO₂-SnO₂-Sb₂O₃, tartrazine, dibenzothiophene

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2. X. Chen, G. Chen, F. Gao, P. Yue, High-performance Ti/BDD electrodes for pollutant oxidation, Environ. Sci. Technol. 37 (2003) 5021.
3. M. H. P. Santana, L. M. Da Silva, L. A. De Faria, (2003). Investigation of Surface Properties of Ru-Based Oxide Electrodes Containing Ti, Ce and Nb. Electrochim. Acta, 48 (13), 1885.