The Formation of Adsorbed O(2-) and OH(-) on a Ag Electrode in Dilute CrO4(-2) Electrolytes.

Abstract

Surface enhanced Raman scattering has been used to detect in situ the formation of O= and OH- adsorbed on a Ag electrode in an aqueous solution of 25 micromolar Na2Cr2O7 and .01 to .001 M KC1. Both oxide and hydroxide adsorbates are observed after completion of an oxidation-reduction cycle in a standard voltammetry experiment. As the Ag electrode voltage is swept cathodically, the O=ads is protonated to form more OH-ads but, unlike in MnO4- solutions, no further protonation to form H20 occurs at any cell voltage. The addition of O2 gas to the electrolyte deprotonates the adsorbed OH- to form an oxide covered surface. These results for CrO4 solutions are contrasted with previous results for MnO4 electrolytes to obtain information about the nature of the metal-solution interface in chromate passivated metal surfaces. Keywords: Catalysis, Passivation, Metal surfaces, Protonation, Metal oxide absorbates, Silver, Electrodes, Hydroxides.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Feb 25, 1988
Accession Number
ADA191513

Entities

People

  • Jennifer L. Bates
  • Paul B. Dorain

Organizations

  • Amherst College

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Catalysis
  • Cells
  • Chemical Synthesis
  • Chemistry
  • Chromium Compounds
  • Electrodes
  • Frequency
  • Hydroxides
  • Lasers
  • Materials
  • Measurement
  • Metal Oxides
  • Military Research
  • New York
  • Raman Scattering
  • Scattering
  • Standards

Fields of Study

  • Chemistry

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Electrochemical Surface Science