@article{b4ab135c6b4d416ea7a86126151a44e3,
title = "Formation and Nature of Carbon-Containing Tribofilms",
abstract = "Minimizing friction and wear at a rubbing interface continues to be a challenge and has resulted in the recent surge toward the use of coatings such as diamond-like carbon (DLC) on machine components. The problem with the coating approach is the limitation of coating wear life. Here, we report a lubrication approach in which lubricious, wear-protective carbon-containing tribofilms can be self-generated and replenishable, without any surface pretreatment. Such carbon-containing films were formed under modest sliding conditions in a lubricant consisting of cyclopropanecarboxylic acid as an additive dissolved in polyalphaolefin base oil. These tribofilms show the same Raman D and G signatures that have been interpreted to be due to the presence of graphite- or DLC films. Our experimental measurements and reactive molecular dynamics simulations demonstrate that these tribofilms are in fact high-molecular weight hydrocarbons acting as a solid lubricant.",
keywords = "DLC film, Raman spectroscopy, carbon tribofilm, friction polymer, lubricant additive",
author = "Hongxing Wu and Khan, {Arman Mohammad} and Blake Johnson and Kiran Sasikumar and Chung, {Yip Wah} and Wang, {Q. Jane}",
note = "Funding Information: The authors would like to thank the support from the US National Science Foundation (grant no. CMMI-1662606) and Northwestern University (the McCormick Research Catalyst Awards Fund grant no. 10038293). We thank Valvoline for providing PAO lubricants, Dr. Ali Erdemir for providing the DLC film, and Profs. Jiaxing Huang, Hong Liang, and Ashlie Martini for critical reading of this manuscript. This work made use of the Keck-II Facility of Northwestern University{\textquoteright}s NUANCE Center, which has received support from the Keck Foundation, the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205), the Materials Research Center (NSF DMR-1121262), the McCormick Research Catalyst Awards Fund, grant no. 10038293, and the International Institute for Nanotechnology (IIN) at Northwestern University. We would like to thank Dr. Xinqi Chen for his help in conducting FTIR spectroscopy. Helpful discussions with Professor Guangneng Dong in Xi{\textquoteright}an Jiaotong University, Dr. Xingliang He and Dr. Michael Desanker are acknowledged. H.W. would also like to acknowledge the scholarship support from China Scholarship Council (CSC, no. 201606280181). This research was supported in part through the computational resources and staff contributions provided for the Quest high performance computing facility at Northwestern University, which is jointly supported by the Office of the Provost, the Office for Research, and Northwestern University Information Technology. The research also used computational resources from Center of Nanoscale Materials (CNM) as result of accepted user proposal number CNM 56595. Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract no. DE-AC02-06CH11357. Publisher Copyright: {\textcopyright} 2019 American Chemical Society.",
year = "2019",
month = may,
day = "1",
doi = "10.1021/acsami.8b22496",
language = "English (US)",
volume = "11",
pages = "16139--16146",
journal = "ACS Applied Materials and Interfaces",
issn = "1944-8244",
publisher = "American Chemical Society",
number = "17",
}