EFFECT OF ADATOMS IN THE ELECTROCATALYSIS OF HCOOH OXIDATION - A THEORETICAL-MODEL

A simple model for simulating the electrooxidation of HCOOH on single crystal surfaces of Pt catalyzed by adatoms is presented. The substrat e is represented as a square or hexagonal array of lattice points, whi ch may be occupied by adatoms or poisoning species. Analytic expressio ns for the oxidation current as a function of the adatom coverage are given. Third body effects as well as real improvement of the catalytic activity are analyzed. The model fits satisfactorily some experimenta l data for the electrooxidation of formic acid on Pt/adatoms systems.