Reversible adsorption change of 2-amino-4,5-imidazoledicarbonitrile on Ag electrode surfaces by potential-dependent surface-enhanced Raman scattering

Abstract

The potential-induced adsorption change of 2-amino-4,5-imidazoledicarbonitrile (AIDCN) on Ag electrode surfaces has been examined by surface-enhanced Raman scattering (SERS) in an applied potential range between -1.0 and 0.2 V. Upon adsorption, AIDCN has a substantial interaction with the Ag metal surfaces via its two nitrile groups. The CN stretching peaks at similar to 2200 cm(-1) appeared to be more intensified and redshifted at a negative potential. The deconvolution peak analysis of the CN bands at various voltages suggests that there should be a change in binding modes of AIDCN on Ag surfaces. This potential-dependent orientation change appeared to be reversible. The density functional theory (DFT) calculation of AIDCN on Ag cluster atoms is used to explain its potential-dependent adsorption. Copyright (c) 2010 John Wiley & Sons, Ltd.