Effects of the geometry and operating temperature on the stability of Ti/IrO2–SnO2–Sb2O5 electrodes for O2 evolution

Abstract

Ternary IrO 2 -Sb 2 O 5 -SnO 2 anode has shown its superiorities over IrO 2 and many other electrocatalysts for O 2 evolution, in terms of electrochemical stability, activity and cost. The performance of IrO 2 -Sb 2 O 5 -SnO 2 anodes is affected by its electrochemical properties and operating conditions. In this paper, the electrochemical stability and activity of the Ti/IrO 2 -Sb 2 O 5 -SnO 2 anodes prepared with three different geometries were investigated under different operating conditions. It was found that anodes with large mean curvature have high electrochemical stability. Although increasing temperature results in a decrease in the stability of Ti/IrO 2 -Sb 2 O 5 -SnO 2 , the anode with a mean curvature of 200 m -1 still shows acceptable service life even at 70°C. This tolerance of high temperature was attributed to the thermal expansion difference between the substrate and the coating layer, the redox window for Ir(V)/ Ir(IV) conversion, and the redox reversibility of Sb and Sn species in the coating layer.

Electrochemical combustion of indigo at ternary oxide coated titanium anodes

“…This procedure was repeated eight times. After the final coating, the electrodes were maintained at 550 o C for 1 h in order to calcinate the polymer and form the ternary oxide (IrO 2 -SnO 2 -Sb 2 O 5 ); XRD analysis confirmed at such at temperature these oxide phases are obtained [22]. The temperature did not exceed 600 o C to avoid the formation of TiO 2 that markedly reduces the electrocatalytic properties of the Ti/IrO 2 -SnO 2 -Sb 2 O 5 coating due to passivation [23].…”

IrO2-Ta2O5|Ti electrodes prepared by electrodeposition from different Ir:Ta ratios for the degradation of polycyclic aromatic hydrocarbons

“…This result was attributed to higher adsorption of organics on the anode surface. Results like these, when combined with improved industrial success of mixed metal oxides [30] and the higher corrosion resistance and longer service life of IrO 2 -based anodes as compared to RuO 2 -based ones [31][32][33], justify the interest in the optimization of the synthesis of IrO 2 -based dimensionally stable anodes.…”

Decolorization of Methyl Orange Dye at IrO2‐SnO2‐Sb2O5 Coated Titanium Anodes

“…Initial MO solutions like those used for obtaining Fig. Alternatively, Qin et al justified the effect of temperature on the basis of the enhanced diffusion molecules towards the electrode surface [26]; moreover, temperature favors the breakage of the bonding between the organic molecule and solvated water. Generally speaking, high temperatures enhance the activity of electrocatalysts.…”

“…Indeed, it has been demonstrated that these oxidizing ions can be formed in solutions containing sulfate ions during electrolyses with Ti/IrO 2 -SnO 2 -Sb 2 O 5 electrodes. Alternatively, Qin et al justified the effect of temperature on the basis of the enhanced diffusion molecules towards the electrode surface [26]; moreover, temperature favors the breakage of the bonding between the organic molecule and solvated water. Fig.…”