Computer simulation of reversible electrochemical catalyst promoter dosing

Grand Canonical Monte Carlo simulations were used to study the growth of a Na layer onto a O–p(2 × 2)–Pt(1 1 1) surface. At the beginning of the deposition, the film presents a disordered structure which becomes progressively ordered as the coverage increases due to the repulsive lateral interactions between the adsorbates. We found some ordered structures like p(16 × 16), p(14 × 14) and p(12 × 12) which appears at coverages l lower than Θ ∼ 0.007, in all these overlayers the Na adatoms are adsorbed on fcc-hollow sites of the oxide surface.