INVESTIGADORES
BARBERO Cesar Alfredo
artículos
Título:
Electrochemical mass transport studied by probe beam deflection: potential step experiments
Autor/es:
CESAR A BARBERO; MARIA C. MIRAS; RUEDIGER KOETZ
Revista:
ELECTROCHIMICA ACTA
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 1992 vol. 37 p. 429 - 433
ISSN:
0013-4686
Resumen:
The deflection of a probing
laser beam aligned parallel to a planar electrode was monitored during
potential step experiments. The electrochemical systems investigated were Ag
deposition and dissolution on Pt, the Fe(CN)3−/4−6 redox
reaction on Pt and the electrochromic charge storage reaction in anodic iridium
oxide (AIROF) films. The experimental probe beam deflection (PBD) transients
can be simulated using simple models for the concentration profiles developed
for mass transport controlled reactions. The results show that different
approaches have to be used for mass transport controlled reactions and for
reactions limited by a depletion of the reactant or reacting sites. The PBD
transients measured for different beam distances allow the determination of the
diffusion coefficients of the moving ions. In order to measure the diffusion
coefficient of a single ion a supporting electrolyte has to be used. On the
basis of the presented examples the relation between cyclic deflectograms and
voltammograms is also briefly discussed.