Microwave-prepared Ti/RuO₂-IrO₂ anodes: Influence of IrO₂ content on atrazine removal

Electrochemical oxidation is a promising technology for treating wastewater, although the search for new efficient and economically viable electrode materials is still necessary. Within this context, mixed metal oxide anodes appear as excellent alternatives, but their formulation is still an important point to study, looking for obtaining low-cost materials with high electrocatalytic efficiencies. In the search for these highly-efficient an-odes, here, we prepared three different coatings (RuO2)(0.7)(IrO2)(0.3), (RuO2)(0.8)(IrO2)(0.2), and (RuO2)0.9(IrO2)0.1 using microwave hybrid heating. All the prepared anodes exhibit excellent physical and electrochemical properties. However, as the proportion of IrO2 increases in the anode, the voltammetric charge and the contribution of the internal active sites increase, as well as the capacity for the electrochemical generation of hypochlorite ions. The electrochemical treatment of atrazine was performed using the synthesized electrodes and applying different current densities (20, 40, 60 mA cm(-2)). Faster and more efficient electrochemical oxidation occurs by applying 20 mA cm(-2, )regardless of the anode used, and the (RuO2)(0.7)(IrO2)(0.3) anode reaches the best performance. Finally, an important figure of merit was analyzed, the electrical energy by one order of magnitude (E-EO) used to remove atrazine. The anode (RuO2)(0.7)(IrO2)(0.3) reduced the EEO down to two folds for the optimal current density (20 mA cm(-2)) compared with the other anodes studied, highlighting its good features for treating effluents contaminated with pesticides.