Electrochemical behaviour of Au(111) vicinal faces: atomic structure stability of Au(755) and Au(332) surfaces

The electrochemical behaviour of Au(755) and Au(332) faces in contact with diluted HClO4 or H2SO4 aqueous solutions is investigated in the double layer potential range. The potentials of zero charge (pzc) measurements obtained from differential capacity curves (C(E)) reveal that the well-known (√3×22) reconstruction of the Au(111) plane does not appear on these vicinals. We compare this result with recent structural determinations of Au(111) vicinal surfaces obtained in an ultra-high-vacuum (UHV) environment. The remarkable agreement from both determinations strongly suggests that Au(755) and Au(332) surfaces are stable and unreconstructed both in UHV and in an electrolytic environment.