Electrochemical comparative study of Ti/Ta2O5/Pt-RuO2-IrO2 and Ti/Ta2O5/Pt anodes: Stability, service lifetime, and electrooxidation performance

This work aimed to compare the stability, service lifetime, and electrooxidation performance of Ti/Ta2O5/Pt-RuO2-IrO2 (PRI) and Ti/Ta2O5/Pt (Pt) electrodes thermally prepared. The service lifetime study performed under 410 mA/cm(2) in a 9N H2SO4 showed that PRI electrode had six (06) times longer lifetime than the Pt electrode. Bulk electrolysis experiments were carried out on Pt and PRI under 20 mA/cm(2). COD removal, current efficiency (CE), specific energy consumption (SEC), electrical energy cost, and anode efficiency (eta) were estimated. Both electrodes lead to the conversion of the parent compounds. However, the Pt electrode was best suited for amoxicillin (AMX) electrooxidation with 36.89% by COD removal in KClO4 0.1 M. Besides, the PRI electrode provided the best performances for the AMX electrooxidation (8.15%) and telebrix (TLX) (29.28%) in HClO4 0.1 M and KClO4 0.1 M, respectively. The presence of NaCl enhanced significantly the organic compound electrooxidation in terms of COD removal, CE, SEC, electrical energy cost, and eta on the both electrodes. This is probably because of the co-action of direct and indirect (by active chlorine) oxidations. But the PRI electrode presented the best performance in the presence of chloride ions. In summary, the experimental conditions can determine the performance of an anode.