Silver Electrode Surface Research Articles

Carbon dioxide conversion to hydrocarbons at silver electrode surfaces: Raman Spectroscpic evidence for surface carbon intermediates

Intense Raman spectra from silver electrode surfaces at −0.2 V (SCE) in 0.1 M KF (and other electrolyte) solutions are interpreted in terms of graphitic carbon surface layers. Similar spectra have been recorded from dry silver surfaces polished in an atmosphere of air or CO 2. The source of carbon in the electrochemical studies appears to be atmospheric CO 2 which generates the electroactive species: aquated CO 2 (at pH 5.5) and CO 3 2−(at pH 11). It appears probable that CO 2 in its solution form is electroreduced to an unstable silver surface-formate complex which in turn spontaneously decomposes to carbon.

Surface Raman spectra of nucleic acid components adsorbed at a silver electrode

A spectroelectrochemical method based on the enormous intensity enhancement for Raman scattering on an electrode surface is used in order to obtain high resolution vibrational spectra of nucleic acid components in rather dilute aqueous solutions.The laser Raman spectra of adenine, adenosine, and adenosine-5' -monophosphate (5'-AMP) adsorbed at a silver electrode surface have been recorded in the spectral range of loo to 3400 cm−1 . The vibrational bands are sensitive to the adsorption process and exhibit a significantly enhanced intensity.The purine ring-breathing mode at 730 cm−1 shows in all components an enormous enhancement in the intensity of the Raman scattering. A qualitatively similar high Hainan intensity shows the purine skeleton vibration at 1340 cm−1 . In 5'-AMP appears a very intensive band at 248 cm−1 , which is attributed to the Ag-PO32− vibration. The intensity of the Raman scattering will be strongly influenced by these ionic PO32− -group and in AMP a marked enhancement of Raman bands in observed.

A Raman spectroscopic study of complexes of thiocyanate at the silver electrode surface

AbstractRaman spectra of thiocyanate at the surface of a silver electrode and in a series of aqueous test solutions were compared. The results indicate that spectral variations can be correlated with changes in bonding stoichiometry at the electrode surface as a function of potential.

Thiocyanate adsorption and corrosion at silver electrodes. A Raman spectroscopic study

Laser Raman spectra have been obtained from silver electrode surfaces in contact with acidic and basic solutions containing thiocyanate ions. At pH 2.8, spectra obtained in the potential interval –0.8 (s.c.e.) to –0.4 V (s.c.e.) have been interpreted in terms of adsorbed S-bonded thiocyanate. At pH 5.8 an insoluble passivating film of a basic silver thiocyanate appears to form at potentials more anodic than zero (s.c.e.).

Spectroscopic evidence for hydrated electrons in the electrolysis of water

This paper describes the observation and measurement of a strong absorption at 6 330 Å by a species produced very close to a polished silver cathode in the electrolysis of aqueous solutions. The species is likely to be the hydrated electron, thus corroborating some earlier chemical evidence. The technique involves directing a laser beam along a long, curved, polished, silver electrode surface and measuring very small changes in light transmission by modulating the electrolytic current at a frequency to which the detector's amplifier has been tuned.