RECTIFICATION BY THE ELECTRICAL DOUBLE LAYER AND ADSORPTION KINETICS
Abstract
Qualitative and quantitative treatments are given of non-faradaic rectification by the electrical double layer for specific adsorption of a neutral substance or an ionic species in presence of a large excess of supporting electrolyte. Control of the mean charge (q) and/or mean potential (E) is considered. Rectification at constant q results in a shift of E for an ideal polarized electrode and vice-versa. It is best to maintain E constant and to supply the rectification charge by means of a double pulse method. A theory of this method is developed without assumption about the explicit form of the rate equation for adsorption kinetics. The charge variation due to rectification is expressed in terms of the elements of the equivalent circuit for the non-faradaic impedance and the latter are given as functions of thermodynamic and kinetic parameters for adsorption. The influence of frequency is analyzed; the general equation can be applied directly to the analysis of experimental results. Particular types of adsorption kinetics are also discussed. The method is applicable to frequencies greater than 1 mc at which non-faradaic impedance measurements with a bridge are hardly feasible. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1961
- Accession Number
- AD0256365
Entities
People
- Mitsugi Senda
- Paul Delahay
Organizations
- Louisiana State University