Valuable information about the kinetics of reactions occurring at the surface of an électrode can be obtained from the study of the time dependence of the potential of a working électrode during the non-steady state electrolysis which follows the forcing through the cell of a constant high current density. When the rate of the electrolysis dépends solely upon the speed of diffusion of the depolarizer, the product îT'/i, of the constant current and the square root of the transition time, remains constant. When the rate of electrolysis is also controlled by a chemical reaction, the product iï"A decreases linearly with the current density. This product aoquires abnormally high values when the electrolysis process is accompanied by electrocapillary convection. The study of the relation between the product ir'A and the current i may also give a better understanding of the action upon the mechanism of electrolysis of substances adsorbed on the électrode. (1) Thia paper, presented at the Miniature Meeting of the Philadelphia Section of the American Chemical Society, January 29, 1053, is a aummary of the thesis presented by Dr. Lucien Gierst in partial fulfillment of the requirement for the Doctor's degree at the University of Brussels in 1952. (2) Houdry Process Corporation, Marous Hook, Penna. (3) H. F. Weber, Wied. Ann., 7, 537 (1879). (4) H. J. S. Sand, Phil. Mao-, [6] 1, 45 (1901). (5) E. Muller and K. Schwabe, Z. Elektrochem., 39, 414 (1933). (6) A. Rius, J. Llopis and S. Polo, Anales fia. quim. Esp., 4SB, 469 (1949). (7) L. Gierst and A. Jxilîard. "Proceedinga of the 2nd Meeting of électrode (approximately 300 sq. mm.), the po tential of the working électrode varies with the time during the transienttime {k-k) accordin g to one of the three curves of Fig. 1.
Information concerning the kinetics of electro ‐oxidation of methanol and formic acid in acid solution at a stationary platinum electrode can be obtained from the study of cyclic voltamgrams. The voltamgrams are obtained by recording the current density of the working electrode while its potential is scanned back and forth at constant rate between adequate potentials. The analysis of the shape of cyclic voltamgrams and of the effect of the rate of scanning on this shape sustains the hypothesis that the electro‐oxidation of organic compounds to carbon dioxide and water is limited by the rate of formation of some intermediate platinum‐carboxo surface compound. The thermodynamic yield of the electrode reaction seems to be limited by the stability of this intermediate compound.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.