Influence of the Sb content in Ti/SnO₂-Sb electrodes on the electrocatalytic behaviour for the degradation of organic matter

In this paper, Ti/SnO₂-Sb electrodes with different Sb dopant amounts were successfully fabricated on acid-treated Ti substrates by a thermal decomposition method; this was done in an attempt to examine the effect of the doping amount on the electrochemical activity and stability of the electrode. The physicochemical properties of the prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM)-energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The electrochemical properties were investigated by linear sweep voltammetry (LSV), and the stability was studied via accelerated lifetime testing. The electro-catalytic activity of the prepared Ti/SnO₂-Sb electrodes was strongly dependent on the amount of the Sb dopant, leading to a change in the OER overpotential. Among the prepared samples, the Ti/SnO₂ electrode with 10% of a Sb dopant showed the highest catalytic activity for oxygen evolution reaction (OER), and 87% of COD removal with 20 mA cm⁻² of current density for 60 min was achieved in the presence of 10.0 g L⁻¹ of chloride. The findings reported herein suggest that the Ti/SnO₂ electrode with an optimized Sb dopant amount shows enhanced electro-catalytic performance by easily generating active hydroxyl radicals, which act as strong oxidizing agents.