Time-resolved surface-enhanced infra-red study of molecular adsorption at the electrochemical interface

The adsorption and desorption of fumaric acid at a highly oriented Au(111) electrode surface have been investigated in perchloric acid by surface-enha nced infra-red spectroscopy with time resolutions ranging from microseconds to seconds. The time-resolved spectral measurements can provide informatio n on the kinetics and dynamics occurring at the interface. Fumaric acid is adsorbed on the surface through one of its two carboxyl groups by releasing a proton and orients perpendicularly with respect to the surface. The mole cule is randomly adsorbed without lateral interactions and desorbed from th e surface by a hole-nucleation and growth mechanism. (C) 1999 Elsevier Scie nce B.V. All rights reserved.