Modification of wetting properties of laser-textured surfaces by depositing triboelectrically charged Teflon particles
Authors: Bayer I.S., Brandi F., Cingolani R., Athanassiou A.
Autors Affiliation: Center for Biomolecular Nanotechnologies at UNILE, Istituto Italiano di Tecnologia (IIT), Via Barsanti 1, 73010 Arnesano Lecce, Italy; Department of Mechanical and Aerospace Engineering, University of Virginia, 122 Engineer\’s Way, Charlottesville, VA 22904, United States; Italian Institute of Technology (IIT), via Morego 30, 16152 Genoa, Italy
Abstract: Hydrophilic laser-textured silicon wafers with natural oxide surfaces were rendered hydrophobic by depositing electrostatically charged submicrometer Teflon particles, a process termed as triboelectric Teflon adhesion. Silicon surfaces were micro-textured (~5 µm) by laser ablation using a nanosecond pulsed UV laser. By varying laser fluence, micro-texture morphology of the wafers could be reproduced and well controlled. Wetting properties of the triboelectrically charged Teflon-deposited surfaces were studied by measuring apparent static water contact angles and water contact angle hysteresis as a function of substrate roughness and the amount of Teflon deposited. A similar study was also performed on various micro-textured silicon carbide surfaces (sandpapers). If the average substrate roughness is between 15 and 60 µm, superhydrophobic surfaces can be easily formed by Teflon deposition with water contact angle hysteresis less than 8. This environmentally benign solvent-free process is a highly efficient, rapid, and inexpensive way to render contact-charged rough surfaces hydrophobic or superhydrophobic.
Journal/Review: COLLOID AND POLYMER SCIENCE
Volume: 291 (2) Pages from: 367 to: 373
KeyWords: Laser ablation; Triboelectric polymer; Teflon; Textured surfaces; SuperhydrophobicityDOI: 10.1007/s00396-012-2757-0Citations: 20data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-01-26References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here