Self-assembly of insoluble porphyrins on Au(111) under aqueous electrochemical control

© 2011 American Chemical Society

Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 27(2011), 24 vom: 20. Dez., Seite 14828-33
1. Verfasser: Sadegh Hassani, Sedigheh (VerfasserIn)
Weitere Verfasser: Kim, Youn-Geun, Borguet, Eric
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2011
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Electrolytes Perchlorates Porphyrins tetraphenylporphyrin Water 059QF0KO0R Gold 7440-57-5
Beschreibung
Zusammenfassung:© 2011 American Chemical Society
Self-assembled monolayers of a water-insoluble porphyrin, tetraphenyl porphyrin (TPP), in the presence of an aqueous electrolyte were characterized in situ with electrochemical scanning tunneling microscopy (EC-STM) at working electrode potentials of between 0.5 and -0.2 V. Isolated domains of TPP monolayers with differing orientation were observed on Au(111) in 0.1 M HClO(4) over this entire potential window. Individual TPP molecules could be resolved over a range of 700 mV, from open circuit potential (OCP) to near the hydrogen evolution potential. The unit cell is square, and the distance between neighboring molecules is about 1.4 ± 0.1 nm. High-resolution images allow the internal molecular structure to be discerned. No changes in the STM contrast of individual molecules were observed as the potential was changed. In a neutral electrolyte (0.1 M KClO(4), pH ~6), the potential range of stability of ordered structures is reduced. On HOPG, TPP forms ordered hexagonal structures with a lattice constant of about 2.6 nm in the double-layer potential region in 0.1 M HClO(4)
Beschreibung:Date Completed 24.04.2012
Date Revised 21.11.2013
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la201308g