The Effect of Preparation Parameters in Thermal Decomposition of Ruthenium Dioxide Electrodes on Chlorine Electro‐Catalytic Activity

When fabricating a RuO2 electrode, the high electro‐catalytic activity in chlorine evolution is considered as one of the most important factors. Thermal decomposition method carried out under various fabrication conditions including the types of solvents, precursors, and calcination times have led to the enhancement electro‐catalytic activity of RuO2 electrode in chlorine evolution. Nevertheless, it has not been fully investigated how these parameters directly affect to the chlorine evolution efficiency in the RuO2 electrode. Therefore, the aim of this study was to investigate the effect on the chlorine evolution in RuO2 electrodes, depending upon the preparation parameters including solvents, precursors, and calcination times. As major results, the chlorine evolution efficiency was dominantly affected by these three major preparation parameters. The RuO2 electrode fabricated with ethanol as the solvent showed highest chlorine evolution efficiency. The choice of Ru(AcAc)3 as precursor and the increase of the calcination time up to 3 h are also the good choices for increasing chlorine electrocatalytic activities. The chlorine evolution efficiency was not significantly related to the total voltammetric charge but to the outer voltammetric charge, which is affected by the morphology of the RuO2 electrode surface. The size and number of cracks on the electrode surfaces or the outer voltammetric charges increased with easily evaporated solvents, decomposed precursors, and tensile stress from longer thermal treatments.