Formation and Dissolution of Platinum Oxide Film: Mechanism and Kinetics

摘要: Oxide film formation on a smooth platinum electrode in perchloric acid solution has been studied as function of potential, current, time, and history, using constant current controlled potential techniques. Anodic proceeds through two, single electron steps: slow step followed by fast (reversible) one. During reduction the occurs first, step. In case does not occur, is exactly half‐reduced. Complete requires several hours at potential. Three states are thus clearly defined: oxidized, half‐reduced (active), completely reduced or clean. A kinetic equation quantitatively relates time parameters, predicts initial rate open‐circuit decay following formation, strongly suggests that oxide chemisorbed film.