| AVS 62nd International Symposium & Exhibition | |
| Tribology Focus Topic | Thursday Sessions |
| Session TR+TF-ThM |
| Session: | Nanolubricants and Coatings |
| Presenter: | Heather Adams, University of Wisconsin-Milwaukee |
| Authors: | H.L. Adams, University of Wisconsin-Milwaukee M.T. Garvey, Illinois Applied Research Institute O. Furlong, Universidad Nacional de San Luis, Argentina W.T. Tysoe, University of Wisconsin-Milwaukee |
| Correspondent: | Click to Email |
Although tribochemical reactions are common in manufacturing, analysis of the mechanism and products is severely limited by the difficulty of probing a solid-solid interface that changes on small time scales. A method to analyze the gas-phase products of a tribochemical reaction in ultra-high vacuum has been developed to allow insight to be obtained into the decomposition pathways of short-chain alkylthiols on copper foils. A UHV-tribometer is used to probe the alkylthiol-covered copper foil by using a mass spectrometer to measure the products evolved from the surface.
Alkylthiols have been chosen due to their thermal stability on a copper surface1, and their ability to form a tribofilm. Previous studies have found that sulfur moves into the sub-surface layer with rubbing, and the carbon is removed from the surface.2
The shear-induced decomposition of methyl thiolate produces gas-phase methane and measuring the amount of methane produced during each sliding cycle allows the shear-induced reaction rate to be measured. The results are analyzed to give insight into how sheer stress lowers the energy barrier for the decomposition reaction. 3
1. Furlong, O. J. et al. The surface chemistry of dimethyl disulfide on copper. Langmuir26, 16375–16380 (2010).
2. Furlong, O., Miller, B., Kotvis, P., Adams, H. & Tysoe, W. T. Shear and thermal effects in boundary film formation during sliding. RSC Adv.4, 24059 (2014).
3. Adams, H. L. et al. Shear-Induced Mechanochemistry: Pushing Molecules Around. J. Phys. Chem. C119, 7115–7123 (2015).