K. Zawada et J. Bukowska, An interaction of 1,10-phenantroline with the copper electrode in neutral and acidic aqueous solutions: a surface enhanced Raman scattering study, J MOL STRUC, 555, 2000, pp. 425-432
This paper presents the investigations of the Cu electrode/1,10-phenanthrol
ine interface by using surface enhanced Raman scattering (SERS) method. Bot
h neutral and acidic aqueous solutions of I,10-phenanthroline have been stu
died. In order to characterise the adsorbed film its SERS spectrum was comp
ared with the normal Raman spectra of 1,10-phenanthroline monohydrate and i
ts complex with copper (I) chloride in a solid state. Both frequency values
and relative intensities are considerably changed in the SERS spectra in c
omparison to the Raman spectrum of non-adsorbed molecules. The general patt
ern of the SERS spectrum is similar to that of the Raman spectrum of the Cu
(I)-phenanthroline complex, thus suggesting that the Cu electrode surface
is modified by some kind of surface complex. This surface complex was shown
to be stable in a wide range of electrode potentials (up to -1.2 V. As evi
denced by electrochemical experiments (cyclic voltammetry) the modification
of the Cu surface by phenanthroline molecules significantly inhibits the h
ydrogen evolution at negative potentials. The inhibiting effect is more pro
nounced in acidic solutions. The appearance of the bands assigned to the ou
t-of-plane vibrations in the surface Raman spectrum suggests that the plane
of the adsorbed molecules is tilted from the normal to the metal surface.
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