OBSERVATIONS ON ELECTROCHEMICALLY ORIENTED PLATINUM SURFACES

Different orientations of microcrystalline surfaces on polycrystalline platinum were obtained by applying fast periodic potential perturbati ons. The surface orientation depends not only on the potential program but also on the electrolyte used during this treatment. In H2SO4 and HClO4 two different orientations (110) and (100) are developed dependi ng on the lower and upper potential limits. In contrast, only one orie ntation in the direction of a (110) or a (100) single-crystal surface is developed in H3PO4 or HCl respectively. Application of the fast pot ential scan leads to smoothing of the Pt electrode surface.