Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-03T00:30:11.472Z Has data issue: false hasContentIssue false

Atomic Force Microscopy Studies of Microstructure and Properties of Self Assembled Monolayers

Published online by Cambridge University Press:  02 July 2020

Jecksan R. Santiago
Affiliation:
Box 7531, North Carolina State University, Raleigh, NC 27695-7531
E. Barry Troughton
Affiliation:
Lord Corporation, 405 Gregson Drive, Cary, NC, 27511
Richard A. Dennis
Affiliation:
Lord Corporation, 405 Gregson Drive, Cary, NC, 27511
Phillip E. Russell
Affiliation:
Box 7531, North Carolina State University, Raleigh, NC 27695-7531
Get access

Extract

Ex-situ and in-situ studies were performed for self-assembled monolayers (SAMs) formation on mica. The behavior of two surfactants [octadecylphosphonic acid (OPA) and dodecylphosphonic acid (DPA)] in two different solutions [ethanol or tetrahydrofuran (THF)] were studied at different concentrations. A cross section analysis of the monolayer images at partial coverage showed thickness of 1.8 nm, 0.7 nm, and 1.0 nm for OPA, DPA and mixed OPA/DPA, respectively. These values are similar to the ones presented by Xiao and those expected for a monolayer of mixed surfactants as proposed by Whitesides. Since the topography of a monolayer resembles the substrate, the presence of the monolayer at full coverage was determinated by force-distance curve measurements. It was observed that the solvent had the ability to re-dissolve the OPA monolayer, suggesting that the bonding is of a physisorption nature.

Type
Scanned Probe Microscopy: Much More Than Just Beautiful Images
Copyright
Copyright © Microscopy Society of America

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Xiao, X. et al., Langmuir, 12 (1996) 235237.CrossRefGoogle Scholar
2.Whitesides, G.M and Gorman, C.B, The Handbook of Surface Imaging and Visualization, Hubbard, A.T. ed., CRC Press Inc., New York (1995) 713732.Google Scholar
3.Bain, C.D. et al., J. Am. Chem. Soc. 111 (1989a) 321.CrossRefGoogle Scholar