The properties of the ceramic electrodes make them interesting for electrochemical advanced oxidation processes (EAOPs), destined to the elimination of emergent or refractory contaminants, as an alternative to boron-doped-diamond (BDD) electrodes. The oxygen discharge potential (E O2 ) for the ceramic electrodes decreases as the sintering temperature increases, being these values higher than that observed for the Pt electrode and smaller than that for the BDD electrode. This result in a highest rate of 2 COD removal for the electrode sintered at 1050 ºC comparing with the rest of ceramic electrodes under potentiostatic operation. On the other hand, in galvanostatic mode, the performance of the different ceramic electrodes in terms of the degradation of Norfloxacin, used as tested antibiotic, was similar.Comparing the behavior of the ceramic electrode sintered at 1250 ºC and that of the BDD electrode at an applied potential of 3V, it is inferred that although both present similar values in terms of the degradation of Norfloxacin, the rate of removal of the chemical oxygen demand is higher in the case of the BDD.

Antimony‐doped tin oxide electrodes with CuO as sintering aid are presented as an economical alternative to metal‐based electrodes, intended for the electrooxidation process of emerging and recalcitrant organic contaminants in wastewaters. The CuO proportion has been optimized to obtain densified electrodes with a mild thermal cycle (Tmax = 1200°C). One of the manufactured electrodes (97.8 mol.% of SnO2, 1.0 mol.% of Sb2O3, and 1.2 mol.% of CuO) was selected for electrochemical characterization from a physical and morphological analysis. The electrochemical behavior of the selected electrode showed that the addition of CuO as sintering aid widens the electrochemical window and increases the electrode “inactivity”, with respect to an (Sn, Sb)O2 electrode synthesized in the same conditions. In return, the (Sn,Sb,Cu)O2 electrode presents a significantly lower electrochemical rugosity factor. Moreover, the addition of CuO does not change the oxygen evolution reaction mechanism, but it modifies the kinetic parameters, leading to a larger accumulation of hydroxyl radicals. Consequently, the addition of CuO as sintering aid significantly improves the electrochemical properties of the electrode as an electrochemical advanced oxidation process anode with respect to the (Sn,Sb)O2 electrode, at the expense of worsening its electrochemical roughness factor. The results of the electrochemical characterization were confirmed by Norfloxacin degradation tests.

This work explores the possibility of increasing the active surface of a Sb-doped SnO 2 ceramic electrode using CuO as sintering aid, by incorporating petroleum coke as a pore generator. In order to fulfil this goal, three series of (Sb, Sn, Cu) O electrodes with different coke contents were synthetized. The properties of the electrodes, and their microstructure, change significantly as a function of the coke content before sintering. The electrochemical characterization of the synthesized electrodes showed that the coke addition before sintering causes two antagonist effects on the performance of the (Sn, Sb, Cu)O as anodes in electrochemical advanced oxidation processes (EAOP). On one hand, it significantly improves the electro-chemical roughness factor of the electrode, solving the densification problem in this way. On the other hand, it worsens the electrochemical behavior of the electrode: narrowing its electrochemical window; and "activating" it slightly. The addition of coke before sintering changes the kinetic parameters, leading to a kinetic situation in which the accumulation of hydroxyl radicals is slightly lower. A balance must be sought: an intermediate coke content will improve significantly the electrochemical roughness factor of the electrode, but will only worsen slightly its electrochemical behavior, leading to an optimum (Sn, Sb, Cu)O EAOP anode.