Evidence of the synergetic role of charged species and atomic oxygen in the molecular etching of PTFE surfaces for hydrophobic surface synthesis.
The transformation of a poly(tetrafluoroethylene) (PTFE) hydrophobic surface into a superhydrophobic one using a low pressure RF plasma is explored using optical emission spectrometry (OES), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) measurements, mass measurements, and atomic force microscopy (AFM). It is shown that the increase in contact angle is due to an increase of roughness provoked by a chemical etching of the surface. We propose a molecular mechanism for etching that requires the simultaneous presence of atomic oxygen and negatively charged species (electrons) at the PTFE surface.
Université Libre de Bruxelles, Faculté des Sciences, Chimie Analytique et chimie des interfaces, cp 255, Bld du Triomphe 2, B-1050 Brussels, Belgium.
Nicolas
N
Vandencasteele
Bérangère
B
Broze
Stéphanie
S
Collette
Caroline
C
De Vos
Pascal
P
Viville
Roberto
R
Lazzaroni
François
F
Reniers
D000327:Adsorption; D004583:Electrons; D057927:Hydrophobic and Hydrophilic Interactions; D010100:Oxygen / Q000737:chemistry*; D010316:Particle Size; D011138:Polytetrafluoroethylene / Q000138:chemical synthesis* / Q000737:chemistry*; D013499:Surface Properties
D011138:Polytetrafluoroethylene; D010100:Oxygen