Accession Number : AD0715667

Title :   Specular Reflectivity Studies of the Adsorption of Halide Anions on Gold Electrodes in 0.2M HClO4.

Descriptive Note : Technical rept.,

Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OHIO ELECTROCHEMISTRY RESEARCH LAB

Personal Author(s) : Takamura,Tsutomu ; Takamura,Kiyoko ; Yeager,Ernest

Report Date : 15 SEP 1970

Pagination or Media Count : 35

Abstract : The specular reflectivity of gold has been measured in 0.2M HC1O4 with and without halide ions present. The reflectivity potential curves depend on the halide concentration at potentials where halide ions are adsorbed. Increasing halide ion concentration decreases the reflectivity with a limiting value approached at higher halide ion concentrations. The decrease in reflectivity produced by anion adsorption also is potential dependent and approaches a limiting value at more anodic potentials. Hysteresis is evident in the reflectivity-potential curves recorded with cyclic linear potential sweeps when the sweep rates and halide ion concentrations are such that diffusion of halide ions to and from the electrode is expected to be rate controlling. Potential-step techniques and simultaneous reflectivity measurements have been used to demonstrate diffusion control of the adsorption kinetics at low halide concentrations. The factors involved in the change of the reflectivity of the gold-electrolyte solution interface with potential and anion adsorption are discussed. (Author)

Descriptors :   (*GOLD, *ADSORPTION), (*ELECTRODES, ADSORPTION), (*IONS, ADSORPTION), ELECTROCHEMISTRY, REFLECTIVITY, ELECTROLYTIC CELLS, IODIDES, BROMIDES, CHLORIDES

Subject Categories : Physical Chemistry
      Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE