Octadecyltrichlorosilane Deposition on Mica Surfaces: Insights into the Interface Interaction Mechanism.
Surface functionalization by alkylsilanes has been widely used in many engineering applications. In this work, a systematic investigation was conducted on the deposition behaviors of octadecyltrichlorosilane (OTCS) on freshly cleaved mica surfaces that possess a low density of reactive sites (i.e., silanol groups) by a vapor-deposition method. The deposition of OTCS molecules on mica was found to follow a two-stage process, as monitored by measuring the surface morphology using an atomic force microscope and wettability of the samples obtained at different deposition times. The contact mechanics behaviors and interaction forces of the as-obtained OTCS surfaces were characterized using a surface forces apparatus. The contact mechanics tests demonstrate that the OTCS coatings can significantly reduce the surface adhesion and adhesion hysteresis in air. The force-distance profiles of the OTCS surfaces obtained via a shorter deposition time (e.g., 2, 8 h) in aqueous solutions could be reasonably described by the classical Derjaguin-Landau-Verwey-Overbeek theory. However, for the OTCS surfaces obtained by longer deposition times (e.g., 48 h), hydrophobic interaction and steric interaction play an important role due to the enhanced surface hydrophobicity and roughness. Our results provide useful insights into the physicochemical characteristics of alkylsilane deposition and the surface interaction mechanisms of deposited alkylsilanes at solid-air and solid-water interfaces.
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Jun
J
Huang
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Xiaokong
X
Liu
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Xiaoyong
X
Qiu
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Lei
L
Xie
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Bin
B
Yan
School of Material Science & Engineering, Taiyuan University of Science and Technology , Taiyuan 030024, China.
Xiaogang
X
Wang
School of Material Science & Engineering, Taiyuan University of Science and Technology , Taiyuan 030024, China.
Qingxue
Q
Huang
Department of Chemical and Materials Engineering, University of Alberta , Edmonton, Alberta, Canada T6G 1H9.
Hongbo
0000-0002-1432-5979
H
Zeng