Researchers from the State Key Laboratory of Solid Lubrication at the Lanzhou Institute of Chemical Physics have grafted octadecyltrichlorosilane (OTS) onto the graphene oxide (GO)-based dual-layer film composed of GO outerlayer and (3-aminopropyl)triethoxysilane (APTES) self-assembled underlayer, on a Si substrate by taking advantage of the condensation between Si-OH of the hydroxylated OTS and C-OH on graphene oxide surface. Thus, a hydrophobic trilayer film coded as “APTES-GO-OTS’ was prepared successfully.
The investigation on the tribological properties of the trilayer film showed that the prepared film exhibited low adhesion and greatly reduced the friction force in both the micro- and macroscale. Therefore, such a trilayer film is suitable for an application in the lubrication and protection of nano/micro electromechanical systems (NEMS/MEMS).
This novel and feasible strategy is more suitable for construction of NEMS/MEMS lubricant coatings. Moreover, such modification is supposed to be applied in many other areas, such as to boost the wettability of graphene based biomaterials.
The work has received support from the National Natural Science Foundation of China . The findings have been published in J. Phys. Chem. C (J. Phys. Chem. C 2011, 115, 10080–10086).
(a) Proposed chemical structure of GO. (b) Proposed schematic view for the construction of APTES-GO-OTS trilayer film on a Si wafer (Image by WANG Jinqing et al.)