IrO2-ZrO2-SiO2 ternary oxide composites- based DSAs: Activity toward oxygen evolution reaction with long-term stability

Abstract

Background

Higher purity of copper is produced by Electrowinning (EW) in the cathode. A major challenge in this technique is the anodic structure that causes in the energy consumption, corrosion resistance, and contamination of the copper produced in the cathode.

Methods

Ternary metallic oxide (IrO₂-ZrO₂-SiO₂) composites with the different molar percentages of IrO₂: SiO₂ (10:60, 15:55, and 20:50%) were prepared on titanium substrate by the sol-gel technique, and then thermal decomposition to study the impact of IrO₂ and SiO₂ contents on the electrocatalyst performances of the dimensionally stable anodes (DSAs). The physicochemical properties of the DSAs were determined by X-ray diffraction (XRD), Field emission scanning electron microscope (FE-SEM), Atomic force microscopy (AFM), and electrochemical measurements.

Significant findings

FE-SEM and AFM images display the impact of SiO₂ on the crystallization and crystal growth of IrO₂, leading to the formation of finer oxide particles and the porous morphology of the ternary oxide coatings. The DSA composed of 50 % SiO₂ and 20 % IrO₂ (IZS (20–30–50)) with a more porous surface area represented high apparent electrocatalytic activity toward the oxygen evolution reaction with long-term stability as analyzed under cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and accelerated lifetime (ALT) plots.