Bragg-Williams approximation applied to the study of electrosoption in a modified electrode

PASINETTI P.M.; RAMIREZ-PASTOR A. J.; PINTO O. A

San Luis

Taller; XVII Taller Regional de Física Estadística y Aplicaciones a la Materia Condensada; 2019

In this work is presented theBragg-Williams mean field theoretical approach to study the electrosorptionphenomena on a modified electrode. The electrode surface is modified by theirreversible pre-adsorption of a non-electroactive species, which is capable ofblocking a fraction of the surface adsorption sites. Then, a secondelectroactive species is adsorbed on the empty sites. Inter-species lateralinteractions are considered. The adsorption/desorption process involves chargetransfer, that is, when a particle A is adsorbed, an electron is transferred tothe electrode surface. The analysis is based on the study of adsorptionisotherms and voltagrams,considering different interaction energies and impurities concentrations. Thetheoretical approximation is contrasted with Monte Carlo results andexperimental data