STABILITY OF BISMUTH ADLAYERS ON PT(111) ELECTRODES IN THE PRESENCE OF ADSORBED ORGANIC-COMPOUNDS

The interactions of bismuth adlayers with adsorbed organic compounds o n Pt(111) surfaces have been examined using voltammetric techniques. E vidence is provided that adsorbed CO affects bismuth adatoms giving ri se to different adsorption states. After CO stripping, a potential exc ursion to negative potentials allows the surface diffusion of bismuth adatoms to take place in order to attain their most stable state on th e Pt(111) surface. A similar effect on the bismuth adlayer is also car ried out by tetrahydroxy-p-benzoquinone, an organic compound that exhi bits a completely different behavior from that observed for CO adspeci es on Pt(111) electrodes. (C) 1998 Elsevier Science S.A. All rights re served.