RuO2-based anodes with tailored surface morphology for improved chlorine electro-activity

We report the preparation of Dimensionally Stable Anode® coatings with a special surface morphology, which is tailored for the chlorine gas evolution. A simple electro-deposition route is applied to create coatings with large crack sizes and three-dimensionally arranged catalyst spheres on top of the coating surface. This morphology shows an increase of the specific outer electro-catalyst surface area, which is the main working part during intensive chlorine gas evolution. By this means, a decrease of the chlorine overpotential and simultaneously a reduction of the noble metal content can be achieved, which is favorable in terms of energy and resource efficiency of the chlor-alkali industry. The influence of the deposition parameters on phase structure, phase composition, surface morphology and electrochemical properties were investigated using XRD, ICP-OES, SEM, CV and polarization techniques.