| Summary: | Electrocatalytic oxidation (ECO) has attracted attention because of its high efficiency and environmental friendliness in water treatment. The preparation of anodes with high catalytic activity and long service lifetimes is a core part of electrocatalytic oxidation technology. Here, porous Ti/RuO<sub>2</sub>-IrO<sub>2</sub>@Pt, Ti/RuO<sub>2</sub>-TiO<sub>2</sub>@Pt, and Ti/Y<sub>2</sub>O<sub>3</sub>-RuO<sub>2</sub>-TiO<sub>2</sub>@Pt anodes were fabricated by means of modified micro-emulsion and vacuum impregnation methods with high porosity titanium plates as substrates. The scanning electron microscopy (SEM) images showed that RuO<sub>2</sub>-IrO<sub>2</sub>@Pt, RuO<sub>2</sub>-TiO<sub>2</sub>@Pt, and Y<sub>2</sub>O<sub>3</sub>-RuO<sub>2</sub>-TiO<sub>2</sub>@Pt nanoparticles were coated on the inner surface of the as-prepared anodes to form the active layer. Electrochemical analysis revealed that the high porosity substrate could result in a large electrochemically active area, and a long service life (60 h at 2 A cm<sup>−2</sup> current density, 1 mol L<sup>−1</sup> H<sub>2</sub>SO<sub>4</sub> as the electrolyte, and 40 °C). The degradation experiments conducted on tetracycline hydrochloride (TC) showed that the porous Ti/Y<sub>2</sub>O<sub>3</sub>-RuO<sub>2</sub>-TiO<sub>2</sub>@Pt had the highest degradation efficiency for tetracycline, reaching 100% removal in 10 min with the lowest energy consumption of 167 kWh kg<sup>−1</sup> TOC. The reaction was consistent with the pseudo-primary kinetics results with a k value of 0.5480 mol L<sup>−1</sup> s<sup>−1</sup>, which was 16 times higher than that of the commercial Ti/RuO<sub>2</sub>-IrO<sub>2</sub> electrode. The fluorospectrophotometry studies verified that the degradation and mineralization of tetracycline were mainly ascribed to the •OH generated in the electrocatalytic oxidation process. This study thus presents a series of alternative anodes for future industrial wastewater treatment.
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