Artículos de revistas
A Dielectric Model of Self-Assembled Monolayer Interfaces by Capacitive Spectroscopy
Fecha
2012-06-26Registro en:
Langmuir. Washington: Amer Chemical Soc, v. 28, n. 25, p. 9689-9699, 2012.
0743-7463
10.1021/la301281y
WOS:000305661400061
0477045906733254
0000-0003-2827-0208
Autor
Univ Oxford
Universidade Estadual Paulista (Unesp)
Institución
Resumen
The presence of self-assembled monolayers at an electrode introduces capacitance and resistance contributions that can profoundly affect subsequently observed electronic characteristics. Despite the impact of this on any voltammetry, these contributions are not directly resolvable with any clarity by standard electrochemical means. A capacitive analysis of such interfaces (by capacitance spectroscopy), introduced here, enables a clean mapping of these features and additionally presents a means of studying layer polarizability and Cole-Cole relaxation effects. The resolved resistive term contributes directly to an intrinsic monolayer uncompensated resistance that has a linear dependence on the layer thickness. The dielectric model proposed is fully aligned with the classic Helmholtz plate capacitor model and additionally explains the inherently associated resistive features of molecular films.