Surface modification of RuO2 electrodes by laser irradiation and ion implantation: Evidence of electrocatalytic effects

RuO2 thin layers were deposited on Ti supports by thermal decomposition of RuCl3 at 400°C. Some of the samples were subjected to laser irradiation between 0-5 and 1-5 J cm-2. Some others to Kr bombardment with doses between 1015 and 1016 cm-2. Modifications introduced by the surface treatments were monitored by cyclic voltammetry and O2 evolution in H 2SO4 solution. The voltammetric charge increased with surface treatment almost to the same extent for irradiation and bombardment. The electro-catalytic activity turned out much higher for Kr bombarded samples. Raw experimental data were scrutinized in an attempt to separate geometric from electronic factors. True electrocatalytic effects are clearly seen to prevail over purely surface area effects.