Kinetic study of oxygen reduction in acid media on a Os-x(CO)(n) cluster electrocatalyst

Transition metal cluster electrocatalyst based on Os-x(CO)(n) was synthesiz ed by pyrolysis of Os-3(CO)(12) in 1,2 dichlorobenzene (bp approximate to 1 80 degrees C). The synthesized material was characterized by FT-IR, SEM and electrochemically. FT-IR showed that following this chemical route only ca rbonylic clusters are synthesized. The electrocatalytic activity for molecu lar oxygen reduction was studied by a Rotating Ring-Disc Electrode (rrde) t echnique in a 0.5M H2SO4. The results show that the oxygen reduction occurs via multielectron charge transfer (n = 4e), leading to water formation. Th e yield of water formation is more than 99%.