Quantification of fluorine density in the outermost atomic layer.
The outermost atomic layer of perfluorinated thiol monolayers on gold and poly(tetrafluoroethylene) (PTFE) is analyzed by low-energy ion scattering. Absolute quantification of fluorine density in this layer was achieved after calibrating the fluorine signal with a freshly cleaved LiF(100) single crystal. The fluorine density of monolayers of a C8F17-thiol on gold was 1.48 x 10(15) F atoms/cm2, whereas for PTFE a value of 1.24 x 1015 F atoms/cm2 was observed. This difference was explained by the different tilt angles of the thiol on gold and PTFE chains with respect to the surface normal. Both a configurational and a molecular interpretation on the perfluorinated thiol monolayer on gold are given.
van de Grampel
R D
RD
Laboratory of Coatings Technology, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Ming
W
W
Gildenpfennig
A
A
Laven
J
J
Brongersma
H H
HH
de With
G
G
van der Linde
R
R
D003460:Crystallization; D005459:Fluorides / Q000737:chemistry; D005461:Fluorine / Q000032:analysis / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D018020:Lithium Compounds / Q000737:chemistry; D010316:Particle Size; D011138:Polytetrafluoroethylene / Q000737:chemistry; D012542:Scattering, Radiation; D013499:Surface Properties
D018020:Lithium Compounds; C027651:lithium fluoride; D005461:Fluorine; D006046:Gold; D011138:Polytetrafluoroethylene; D005459:Fluorides