ADSORPTION BEHAVIOR OF N-HEXANOL ON AG(111) FROM AQUEOUS 0.05-M KCLO4

A computerized chronocoulometric technique was employed to investigate the adsorption behavior of n-hexanol (NHEX) on the (111) face of a silver single crystal from aqueous 0.05 M KClO4. The charge density, sigma(M), as a function of the applied potential, E, and of the NHEX concentration was analyzed thermodynamically, yielding the Gibbs surface excess and the standard Gibbs energy of adsorption, Delta G degrees(ads), of NHEX as a function of E and sigma(M). A comparison of the experimental adsorption parameters with a molecular model points to a flat orientation of the adsorbed NHEX molecules. The low value of -Delta G degrees(ads) at the potential of maximum adsorption, 18.4 kJ mol(-1), is indicative of the strongly hydrophilicity of silver.