Ionic Liquid Lubrication of Stainless Steel: Friction is Inversely Correlated with Interfacial Liquid Nanostructure
Abstract
Atomic force microscopy (AFM) is used to measure the friction of a stainless steel surface lubricated with six different ionic liquids (ILs). The measurements reveal that, contrary to expectations, friction and the degree of interfacial ionic liquid nanostructure are inversely correlated. Six ILs were confined between a sharp Si tip and a stainless steel surface, and the friction force was measured as a function of normal load. Trihexyl(tetradecyl)phosphonium bis(trifluoromethane)sulfonamide (P 6,6,6,14 TFSI) and trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate (P 6,6,6,14 ( i C 8 ) 2 PO 2 ) are the most effective lubricants, reducing lateral forces and friction coefficients by up to 3 times compared with the imidazolium-based ILs and the shorter-chained P 4,4,4,1 TFSI. Force–separation profiles reveal no obvious interfacial layers for P 6,6,6,14 ( i C 8 ) 2 PO 2 and P 6,6,6,14 TFSI, in contrast to extensive layering for the other ILs. The bulkiness of the [P 6,6,6,14 ] + cation weakens the electrostatic interaction with the anion, resulting in weaker structure near the surface. The sliding AFM tip expels the weak near surface structure with minimal energy loss (low friction), whereas for the strongly structured ILs, more energy is dissipated by breaking the stronger interlayer bonds. The inverse correlation between friction and IL structure can be used to design weakly structured ILs which are excellent lubricants.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Cites
Intermolecular and Surface Forces
Israelachvili, J. N. (2011) · Elsevier eBooks · doi:10.1016/c2009-0-21560-1 · Cited by 8,185 · see citing works
Structure and Nanostructure in Ionic Liquids
Hayes, R. A., Warr, G. G., & Atkin, R. (2015) · Chemical Reviews · doi:10.1021/cr500411q · Cited by 2,303 · see citing works
Self-citationAir and water stable 1-ethyl-3-methylimidazolium based ionic liquids
Wilkes, J. S., & Zaworotko, M. J. (1992) · Journal of the Chemical Society, Chemical Communications · doi:10.1039/c39920000965 · Cited by 1,883 · see citing works
Ionic Liquids at Electrified Interfaces
Fedorov, M. V., & Kornyshev, A. A. (2014) · Chemical Reviews · doi:10.1021/cr400374x · Cited by 1,390 · see citing works
Ionic liquid lubricants: designed chemistry for engineering applications
Zhou, F., Liang, Y., & Liu, W. (2009) · Chemical Society Reviews · doi:10.1039/b817899m · Cited by 1,074 · see citing works
Room-temperature ionic liquids: a novel versatile lubricant.
Ye, C., Liu, W., Chen, Y., et al. (2001) · Chemical Communications · doi:10.1039/b106935g · Cited by 1,053 · see citing works
Yoshizawa‐Fujita, M., Xu, W., & Angell, C. A. (2003) · Journal of the American Chemical Society · doi:10.1021/ja035783d · Cited by 951 · see citing works
Zhang, S., Zhang, J., Zhang, Y., & Deng, Y. (2016) · Chemical Reviews · doi:10.1021/acs.chemrev.6b00509 · Cited by 662 · see citing works
Stachowiak, G. W., & Batchelor, A. W. (2006) · Elsevier eBooks · doi:10.1016/b978-0-7506-7836-0.x5000-7 · Cited by 631 · see citing works
Ionic Liquids as Advanced Lubricant Fluids
Bermúdez, M.-D., Jiménez, A.-E., Sanes, J., et al. (2009) · Molecules · doi:10.3390/molecules14082888 · Cited by 614 · see citing works
A Review of Ionic Liquid Lubricants
Somers, A. E., Howlett, P. C., MacFarlane, D. R., & Forsyth, M. (2013) · Lubricants · doi:10.3390/lubricants1010003 · Cited by 606 · see citing works
Ionicity in ionic liquids: correlation with ionic structure and physicochemical properties
Ueno, K., Tokuda, H., & Watanabe, M. (2010) · Physical Chemistry Chemical Physics · doi:10.1039/b921462n · Cited by 567 · see citing works
Structure in Confined Room-Temperature Ionic Liquids
Atkin, R., & Warr, G. G. (2007) · The Journal of Physical Chemistry C · doi:10.1021/jp067420g · Cited by 506 · see citing works
Self-citationJd, H., & Seddon, K. R. (1999) · Clean Technologies and Environmental Policy · doi:10.1007/s100980050036 · Cited by 414 · see citing works
Xiao, X., Hu, J., Charych, D. H., & Salmerón, M. (1996) · Langmuir · doi:10.1021/la950771u · Cited by 397 · see citing works
Ionic liquids in confined geometries
Perkin, S. (2012) · Physical Chemistry Chemical Physics · doi:10.1039/c2cp23814d · Cited by 391 · see citing works
Antiwear Performance and Mechanism of an Oil-Miscible Ionic Liquid as a Lubricant Additive
Qu, J., Bansal, D. G., Yu, B., et al. (2012) · ACS Applied Materials & Interfaces · doi:10.1021/am201646k · Cited by 356 · see citing works
Araque, J. C., Hettige, J. J., & Margulis, C. J. (2015) · The Journal of Physical Chemistry B · doi:10.1021/acs.jpcb.5b05506 · Cited by 320 · see citing works
Perkin, S., Albrecht, T., & Klein, J. E. (2009) · Physical Chemistry Chemical Physics · doi:10.1039/b920571c · Cited by 303 · see citing works
Solvation forces in simple dense fluids. I
Snook, I. K., & van Megen, W. (1980) · The Journal of Chemical Physics · doi:10.1063/1.439489 · Cited by 299 · see citing works
Oil-miscible and non-corrosive phosphonium-based ionic liquids as candidate lubricant additives
Yu, B., Bansal, D. G., Qu, J., et al. (2012) · Wear · doi:10.1016/j.wear.2012.04.015 · Cited by 283 · see citing works
Self-assembly in the electrical double layer of ionic liquids
Perkin, S., Crowhurst, L., Niedermeyer, H., Welton, T., Smith, A. M., & Gosvami, N. N. (2011) · Chemical Communications · doi:10.1039/c1cc11322d · Cited by 278 · see citing works
Double-layer and solvation forces measured in a molten salt and its mixtures with water
Horn, R. G., Evans, D. F., & Ninham, B. W. (1988) · The Journal of Physical Chemistry · doi:10.1021/j100323a042 · Cited by 244 · see citing works
Temperature-dependent structure of ionic liquids: X-ray scattering and simulations
Kashyap, H. K., Santos, C. S., Annapureddy, H. V. R., et al. (2011) · Faraday Discussions · doi:10.1039/c1fd00059d · Cited by 190 · see citing works
Li, H., Endres, F., & Atkin, R. (2013) · Physical Chemistry Chemical Physics · doi:10.1039/c3cp52421c · Cited by 186 · see citing works
Self-citationBrewer, N. J., Beake, B. D., & Leggett, G. J. (2001) · Langmuir · doi:10.1021/la001568o · Cited by 179 · see citing works
Zhou, Y., Dyck, J. C. H., Graham, T. W., et al. (2014) · Langmuir · doi:10.1021/la5032366 · Cited by 175 · see citing works
Pronounced sponge-like nanostructure in propylammonium nitrate
Hayes, R. A., Imberti, S., Warr, G. G., et al. (2011) · Physical Chemistry Chemical Physics · doi:10.1039/c1cp21080g · Cited by 173 · see citing works
Ionic liquid lubrication: influence of ion structure, surface potential and sliding velocity
Li, H., Rutland, M. W., & Atkin, R. (2013) · Physical Chemistry Chemical Physics · doi:10.1039/c3cp52638k · Cited by 164 · see citing works
Self-citationNeves, C. M. S. S., Carvalho, P. J., Freire, M. G., & Coutinho, J. A. P. (2011) · The Journal of Chemical Thermodynamics · doi:10.1016/j.jct.2011.01.016 · Cited by 164 · see citing works
Quantized friction across ionic liquid thin films
Smith, A. M., Lovelock, K. R. J., Gosvami, N. N., Welton, T., & Perkin, S. (2013) · Physical Chemistry Chemical Physics · doi:10.1039/c3cp52779d · Cited by 159 · see citing works
Ghatee, M. H., Zare, M., Moosavi, F., et al. (2010) · Journal of Chemical & Engineering Data · doi:10.1021/je901092b · Cited by 154 · see citing works
Electrotunable Lubricity with Ionic Liquid Nanoscale Films
Fajardo, O. Y., Bresme, F., Kornyshev, A. A., & Urbakh, M. (2015) · Scientific Reports · doi:10.1038/srep07698 · Cited by 131 · see citing works
Influence of Temperature and Molecular Structure on Ionic Liquid Solvation Layers
Wakeham, D., Hayes, R. A., Warr, G. G., et al. (2009) · The Journal of Physical Chemistry B · doi:10.1021/jp900815q · Cited by 131 · see citing works
Salmerón, M. (2001) · Tribology Letters · doi:10.1023/a:1009026312732 · Cited by 124 · see citing works
Ionic Liquid Lubricants: Basics and Applications
Xiao, H. (2016) · Tribology Transactions · doi:10.1080/10402004.2016.1142629 · Cited by 120 · see citing works
Self-Diffusion Coefficients and Related Transport Properties for a Number of Fragile Ionic Liquids
Harris, K. R., & Kanakubo, M. (2016) · Journal of Chemical & Engineering Data · doi:10.1021/acs.jced.6b00021 · Cited by 110 · see citing works
Tsunashima, K., & Sugiya, M. (2007) · Electrochemistry · doi:10.5796/electrochemistry.75.734 · Cited by 108 · see citing works
Molecular Friction Mechanisms Across Nanofilms of a Bilayer-Forming Ionic Liquid
Smith, A. M., Parkes, M. A., & Perkin, S. (2014) · The Journal of Physical Chemistry Letters · doi:10.1021/jz502188g · Cited by 97 · see citing works
Page, A. J., Elbourne, A. J., Stefanovic, R., et al. (2014) · Nanoscale · doi:10.1039/c4nr01219d · Cited by 94 · see citing works
Ionic liquid nanotribology: mica–silica interactions in ethylammonium nitrate
Werzer, O., Cranston, E. D., Warr, G. G., Atkin, R., & Rutland, M. W. (2011) · Physical Chemistry Chemical Physics · doi:10.1039/c1cp23134k · Cited by 91 · see citing works
Self-citationLi, H., Wood, R. J., Endres, F., et al. (2014) · Journal of Physics Condensed Matter · doi:10.1088/0953-8984/26/28/284115 · Cited by 83 · see citing works
Self-citationPhysicochemical Properties of [C6mim][PF6] and [C6mim][(C2F5)3PF3] Ionic Liquids
Li, J., Hu, Y., Ling, S., et al. (2011) · Journal of Chemical & Engineering Data · doi:10.1021/je200073x · Cited by 80 · see citing works
Adsorbed and near-surface structure of ionic liquids determines nanoscale friction
Elbourne, A. J., Sweeney, J., Webber, G. B., Wanless, E. J., Warr, G. G., Rutland, M. W., & Atkin, R. (2013) · Chemical Communications · doi:10.1039/c3cc42844c · Cited by 78 · see citing works
Self-citationTribotronic control of friction in oil-based lubricants with ionic liquid additives
Cooper, P. K., Li, H., Rutland, M. W., Webber, G. B., & Atkin, R. (2016) · Physical Chemistry Chemical Physics · doi:10.1039/c6cp04405k · Cited by 68 · see citing works
Self-citationLayering of ionic liquids on rough surfaces
Sheehan, A., Jurado, L. A., Ramakrishna, S. N., Arcifa, A., Rossi, A., Spencer, N. D., & Espinosa-Marzal, R. M. (2016) · Nanoscale · doi:10.1039/c5nr07805a · Cited by 59 · see citing works
Cai, Z., Meyer, H. M., Ma, C., et al. (2014) · Wear · doi:10.1016/j.wear.2014.08.002 · Cited by 58 · see citing works
Force microscopy of layering and friction in an ionic liquid
Hoth, J., Hausen, F., Müser, M. H., & Bennewitz, R. (2014) · Journal of Physics Condensed Matter · doi:10.1088/0953-8984/26/28/284110 · Cited by 58 · see citing works
Li, H., Cooper, P. K., Somers, A. E., et al. (2014) · The Journal of Physical Chemistry Letters · doi:10.1021/jz5021422 · Cited by 54 · see citing works
Self-citationLi, H., Somers, A. E., Howlett, P. C., et al. (2016) · Physical Chemistry Chemical Physics · doi:10.1039/c5cp07061a · Cited by 49 · see citing works
Self-citationEffect of ion structure on nanoscale friction in protic ionic liquids
Sweeney, J., Webber, G. B., Rutland, M. W., & Atkin, R. (2014) · Physical Chemistry Chemical Physics · doi:10.1039/c4cp02320j · Cited by 47 · see citing works
Self-citationSeki, S., Serizawa, N., Hayamizu, K., Tsuzuki, S., Umebayashi, Y., Takei, K., & Miyashiro, H. (2012) · Journal of The Electrochemical Society · doi:10.1149/2.032207jes · Cited by 45 · see citing works
Metal ion adsorption at the ionic liquid–mica interface
McDonald, S., Elbourne, A. J., Warr, G. G., & Atkin, R. (2015) · Nanoscale · doi:10.1039/c5nr05833c · Cited by 45 · see citing works
Self-citationNanostructure–Thermal Conductivity Relationships in Protic Ionic Liquids
Murphy, T., Varela, L. M., Webber, G. B., et al. (2014) · The Journal of Physical Chemistry B · doi:10.1021/jp507408r · Cited by 34 · see citing works
Solvation and squeeze out of hexadecane on graphite
Gosvami, N. N., Sinha, S. K., Hofbauer, W., et al. (2007) · The Journal of Chemical Physics · doi:10.1063/1.2741538 · Cited by 33 · see citing works
Is the boundary layer of an ionic liquid equally lubricating at higher temperature?
Hjalmarsson, N., Atkin, R., & Rutland, M. W. (2016) · Physical Chemistry Chemical Physics · doi:10.1039/c5cp05837f · Cited by 31 · see citing works
Self-citationSzewczuk‐Karpisz, K., Wisniewska, M. A., Pac-Sosińska, M., Choma, A., & Komaniecka, I. (2014) · Water Air & Soil Pollution · doi:10.1007/s11270-014-2052-4 · Cited by 28 · see citing works
Li, H., Atkin, R., & Page, A. J. (2015) · Physical Chemistry Chemical Physics · doi:10.1039/c5cp01952d · Cited by 24 · see citing works
Self-citationTowards Phosphorus Free Ionic Liquid Anti-Wear Lubricant Additives
Somers, A. E., Yunis, R., Armand, M. B., et al. (2016) · Lubricants · doi:10.3390/lubricants4020022 · Cited by 24 · see citing works
Influence of Lithium Solutes on Double-Layer Structure of Ionic Liquids
Smith, A. M., & Perkin, S. (2015) · The Journal of Physical Chemistry Letters · doi:10.1021/acs.jpclett.5b02166 · Cited by 23 · see citing works
Sweeney, J., Webber, G. B., & Atkin, R. (2015) · Physical Chemistry Chemical Physics · doi:10.1039/c5cp04787k · Cited by 13 · see citing works
Self-citation
Flagged first, then by citations
Cited by
Sorted by citations
Probing the hydration friction of ionic interfaces at the atomic scale
Li, Z., Liu, Q., Zhang, D., Wang, Y., Zhang, Y., Li, Q., & Dong, M. (2022) · Nanoscale Horizons · doi:10.1039/d1nh00564b · Cited by 30 · see citing works
Controlling the nanoscale friction by layered ionic liquid films
An, R., Qiu, X., Shah, F. U., Riehemann, K., & Fuchs, H. (2020) · Physical Chemistry Chemical Physics · doi:10.1039/d0cp02146f · Cited by 24 · see citing works
- Authors
- Cooper, P. K., Wear, C. J., Li, H., & Atkin, R.
- Affiliations
- The University of Western Australia (AU)
- University of Newcastle Australia (AU)
- Corresponding author
- Atkin, Rob
- Venue
- ACS Sustainable Chemistry & Engineering
- Publisher
- American Chemical Society (ACS)
- Published
- 2017-11-01
- Volume
- 5
- Issue
- 12
- Pages
- 11737-11743
- ISSN
- 2168-0485 (ISSN-L)
- OpenAlex
- W2766249172
- Cited by
- 81
- References
- 61
- Citations by year
- 2026: 3 · 2025: 8 · 2024: 15 · 2023: 6 · 2022: 12 · 2021: 8 · 2020: 10 · 2019: 10 · 2018: 9
- FWCI
- 6.16
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- ACS Sustainable Chemistry & Engineering (publishedVersion)
- UWA Profiles and Research Repository (UWA) (submittedVersion)
- Funders
- University of Western Australia
- Australian Research Council
- Australian Institute of Nuclear Science and Engineering
- Topics
- Physical Sciences › Engineering › Mechanical Engineering › Lubricants and Their Additives
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Force Microscopy Techniques and Applications
- Physical Sciences › Engineering › Mechanical Engineering › Tribology and Lubrication Engineering
- Keywords
- ionic liquids, stainless steel, friction, interfacial nanostructure, imidazolium ionic liquids, friction coefficient, interlayer bonding, lubricant design
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review