Accession Number : ADA265941
Title : Some Electrochemical Consequences of Potential-Induced Surface Reconstruction on Au(100): Double-Layer Nonuniformity and Electrode Kinetics
Descriptive Note : Technical rept.
Corporate Author : PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY
Personal Author(s) : Hamelin, Antoinette ; Stoicoviciu, Livia ; Edens, Gregory J ; Gao, Xiaoping ; Weaver, Michael J
Report Date : Apr 1993
Pagination or Media Count : 31
Abstract : Some consequences of potential-induced surface reconstruction upon the double-layer structure and electrocatalytic properties of Au(100) in aqueous perchloric acid have been explored by means of cyclic voltammetry and differential capacitance measurements, along with in-situ scanning tunneling microscopy (STM) . Initially unreconstructed i.e. (1 x 1) Au(100) yields capacitance-potential (C-E) profiles in dilute (1 mM) perchloric acid in the vicinity of the potential of zero charge, E sub pzc, which are consistent with the presence of an essentially uniform distribution of electronic charge across the surface. Upon forming electrochemically induced hexagonal surface reconstruction by holding the potential below -0.2 V for periods up to ca 20 min, these C-E minima are broadened substantially. The latter observation implicates the presence of electrostatically distinct surface domains with local E sub pzc values that are significantly (0.1-0.2 V) lower as well as higher than that for unreconstructed Au(100), having dimensions at least comparable to the Debye length of the diffuse layer, ca 9.5 nm, in 1 mM HC104.
Descriptors : *SURFACES , *ELECTRODES , *KINETICS , *PERCHLORIC ACID , *GOLD , SCANNING , ELECTRONICS , MEASUREMENT , CRYSTAL STRUCTURE , DISTRIBUTION , TUNNELING , POTENTIAL THEORY , ELECTROCATALYSTS , UNIFORMS , ACIDS , CAPACITANCE , VOLTAMMETRY , PROFILES , LENGTH , LAYERS , OBSERVATION , STRUCTURES , ELECTROCHEMISTRY , MICROSCOPY
Subject Categories : Physical Chemistry
Distribution Statement : APPROVED FOR PUBLIC RELEASE