Skip to main content
Log in

Ionic Liquids as Additives in Water-Based Lubricants: From Surface Adsorption to Tribofilm Formation

  • Original Paper
  • Published:
Tribology Letters Aims and scope Submit manuscript

Abstract

Ionic liquids (ILs) are potential lubricant additives that can potentially perform simultaneously as friction modifiers and anti-wear agents. In addition, they possess good thermal stability, they are non-flammable, they have high polarity with negligible volatility, etc. These characteristics make them also ideal for polar lubricants, like water-based fluids. In this work, the friction and wear mechanisms of stainless steel 316L tested in water-based lubricants containing three different ionic liquids, i.e. Tributylmethylphosphonium dimethylphosphate, (2-hydroxyethyl) trimethylammonium dimethylphosphate and 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate, have been investigated and compared with a reference water-based lubricant containing dodecanoic acid (Lauric acid, C12) as a well-known organic friction modifier. All lubricants formulated with the three ionic liquids showed frictional values lower than the water-based lubricant alone, but higher than the lubricant formulated with C12. A detailed surface adsorption study using Quartz Crystal Microbalance with Impedance measurements (QCM-I) revealed differences in the adsorption kinetics, strength of the adsorption bonds to the metallic surface and also different viscoelastic properties of the adsorbed layers for all the different additives. In the case of one of the ionic liquids (1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate), a tribofilm is formed after some sliding cycles and a significant friction to values lower than that of C12 is observed. A detailed surface and sub-surface investigation of the structure and the chemistry of the wear tracks using SEM/FIB, S(T)EM, and XPS showed that an oxide-rich tribolayer built in the wear track was the cause for the decrease in both wear rate and coefficient of friction. The other ionic liquids were not able to create a tribofilm on the surface of the steel and therefore friction and wear values were higher.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

References

  1. Singh, H., Gulati, I.L.: Tribological behavior of base oils and their separated fractions. Wear (1991). https://doi.org/10.1016/0043-1648(91)90130-M

    Article  Google Scholar 

  2. Zhou, Y., Dyck, J., Graham, T.W., Luo, H., Leonard, D.N., Qu, J.: Ionic liquids composed of phosphonium cations and organophosphate, carboxylate, and sulfonate anions as lubricant antiwear additives. Langmuir (2014). https://doi.org/10.1021/la5032366

    Article  Google Scholar 

  3. Rudnick, L.R.: Lubricant additives: Chemistry and Applications, 2nd edn. Taylor & Francis, London (2009)

    Book  Google Scholar 

  4. Zabawski, E.: Seren-ZDDP: life is full of accidental discoveries. Tribol. Lubr. Technol. 73, 6 (2017)

    Google Scholar 

  5. Spikes, H.: The history and mechanisms of ZDDP. Tribol. Lett. 17, 469 (2004)

    Article  CAS  Google Scholar 

  6. Zhou, Y., Qu, J.: Ionic liquids as lubricant additives: a review. ACS Appl. Mater. Interfaces (2017). https://doi.org/10.1021/acsami.6b12489

    Article  Google Scholar 

  7. Dorr, N., Merstallinger, A., Holzbauer, R., Pejakovic, V., Brenner, J., Pisarova, L., Stelzl, J., Frauscher, M.: Five-stage selection procedure of ionic liquids for lubrication of steel-steel contacts in space mechanisms. Tribol. Lett. (2019). https://doi.org/10.1007/s11249-019-1185-4

    Article  Google Scholar 

  8. Wasserscheid, P., Welton, T. (eds.): Ionic Liquids in Synthesis, 2nd edn. Wiley, Weinheim (2008)

    Google Scholar 

  9. Ye, C., Liu, W., Chen, Y., Yu, L.: Room-temperature ionic liquids a novel versatile lubricant. Chem. Commun. (2001). https://doi.org/10.1039/b106935g

    Article  Google Scholar 

  10. Somers, A., Howlett, P., MacFarlane, D., Forsyth, M.: A review of ionic liquid lubricants. Lubricants (2013). https://doi.org/10.3390/lubricants1010001

    Article  Google Scholar 

  11. Bermudez, M.D., Jimenez, A.E., Sanes, J., Carrion, F.J.: Ionic liquids as advanced lubricant fluids. Molecules (2009). https://doi.org/10.3390/molecules14082888

    Article  Google Scholar 

  12. Qu, J., Luo, H., Toops, J.T., West, B.H., Blau, P.J., Dai, S., Papke, B.L., Gao, H., Kheireddin, B., Chen, C.: Ionic liquids as multi-functional lubricant additives to enhance engine efficiency. Final Rep NFE-12-03876 (2016). https://doi.org/10.2172/1246776

    Article  Google Scholar 

  13. Xiao, H.: Ionic liquids lubricants: basics and applications. Tribol. Trans. (2017). https://doi.org/10.1080/10402004.2016.1142629

    Article  Google Scholar 

  14. Perkin, S., Albrecht, T., Klein, J.: Layering and shear properties of an ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate, confined to nano-films between mica surfaces. Phys. Chem. Chem. Phys. (2010). https://doi.org/10.1039/b920571c

    Article  Google Scholar 

  15. Huang, G., Yu, Q., Ma, Z., Cai, M., Liu, W.: Probing the lubricating mechanism of oil-soluble ionic liquids additives. Tribol. Int. (2017). https://doi.org/10.1016/j.triboint.2016.08.027

    Article  Google Scholar 

  16. Liu, X., Zhou, F., Liang, Y., Liu, W.: Tribological performance of phosphonium based ionic liquids for an aluminum-on-steel system and opinions on lubrication mechanism. Wear (2006). https://doi.org/10.1016/j.wear.2006-03.018

    Article  Google Scholar 

  17. Perkin, S.: Ionic liquids in confined geometries. Phys. Chem. Chem. Phys. (2012). https://doi.org/10.1039/C2CP23814D

    Article  Google Scholar 

  18. Mu, Z., Zhou, F., Zhang, S., Liang, Y., Liu, W.: Effect of the functional groups in ionic liquid molecules on the friction and wear behavior of aluminum alloy in lubricated aluminum-on-steel contact. Tribol. Int. (2005). https://doi.org/10.1016/j.triboint.2004.10.003

    Article  Google Scholar 

  19. Jiang, D., Hu, L., Feng, D.: Crown-type ionic liquids as lubricants for steel-on-steel system. Tribol. Lett. (2011). https://doi.org/10.1007/s11249-010-9726-x

    Article  Google Scholar 

  20. Qu, J., Chi, M., Meyer, H.M., Blau, P.J., Dai, S., Luo, H.: Nanostructure and composition of tribo-boundary films formed in ionic liquid lubrication. Tribol. Lett. (2011). https://doi.org/10.1007/s11249-011-9800-z

    Article  Google Scholar 

  21. Lawes, S.D.A., Hainsworth, S.V., Blake, P., Ryder, K.S., Abbott, A.P.: Lubrication of steel/steel contacts by choline chloride Ionic liquids. Tribol. Lett. (2010). https://doi.org/10.1007/s11249-009-9495-6

    Article  Google Scholar 

  22. Bernat, S., Armada, S., Espallargas, N.: Effect of contamination on the friction and wear of carboxylic acids in aqueous lubricants. Tribol. Lett. (2018). https://doi.org/10.1007/s11249-018-1116-9

    Article  Google Scholar 

  23. Technical Note: The principles of QCM-I, Quartz crystal microbalance with impedance analysis. https://www.gamry.com/assets/Uploads/QCM-I-principles.pdf.

  24. Saftics, A., Prosz, G.A., Turk, B., Peter, B., Kurunczi, S., Horvath, R.: In-situ viscoelastic properties and chain conformation of heavily hydrated carboxymethyl dextran layers: a comparative study using OWLS and QCM-I chips coated with waveguide material. Sci. Rep. (2018). https://doi.org/10.1038/s41598-018-30201-6

    Article  Google Scholar 

  25. Voinova, M.V., Rodahl, M., Johnson, M., Kasemo, B.: Viscoelastic acoustic response of layered polymer films as fluid-solid interfaces: continuum mechanics approach. Phys. Scr. (1999). https://doi.org/10.1238/Physica.Regular.059a00391

    Article  Google Scholar 

  26. McNamara, T.P., Blanford, C.F.: A sensitivity metric and software to guide the analysis of soft films measured by a quartz crystal microbalance. Analyst. (2016). https://doi.org/10.1039/C6AN00143B

    Article  Google Scholar 

  27. Hamrock, B.J., Dowson, D.: Ball Bearing Lubrication-The Elastohydrodynamics of Elliptical Contacts. Wiley, New York (1981)

    Google Scholar 

  28. Zavieh, A.H., Espallargas, N.: Effect of 4-point bending and normal load on the tribocorrosion-fatigue (multi-degradation) of stainless steels. Tribol. Int. (2016a). https://doi.org/10.1016/j.triboint.2016.03.016

    Article  Google Scholar 

  29. Shirley, D.A.: High-resolution X-ray photoemission spectrum of the valance bands of gold. Phys. Rev. B (1972). https://doi.org/10.1103/PhysRevB.5.4709

    Article  Google Scholar 

  30. Du, B., Johannsmann, D.: Operation of the quartz crystal microbalance in liquids: derivation of the elastic compliance of a film from the ratio of bandwidth shift and frequency shift. Langmuir (2004). https://doi.org/10.1021/la035965l

    Article  Google Scholar 

  31. Nalam, P.C., Clasohm, J.N., Mashaghi, A., Spencer, N.D.: Macrotribological studies of poly(L-Iysine)-graft-poly(ethylene glycol) in aqueous glycerol mixtures. Tribol. Lett. (2010). https://doi.org/10.1007/s11249-009-9549-9

    Article  Google Scholar 

  32. Acharya, B., Chestnut, M., Marek, A., Smirnov, A.I., Krim, J.: A combined QCM and AFM study exploring the nanoscale lubrication mechanism of silica nanoparticles in aqueous suspension. Tribol. Lett. (2017). https://doi.org/10.1007/s11249-017-0898-5

    Article  Google Scholar 

  33. Zachariah, Z., Nalam, P.C., Ravindra, A., Ra, A., Mohanlal, A., Wang, K., Castillo, R.V., Espinoza-Marzal, R.M.: Correlation between the adsorption an the nanotribological performance of fatty acid-based organic friction modifiers on stainless steel. Tribol. Lett. (2020). https://doi.org/10.1007/s11249-019-1250-z

    Article  Google Scholar 

  34. Fry, B.M., Moody, G., Spikes, H.A., Wong, J.S.S.: Adsorption of organic friction modifier additives. Langmuir (2020). https://doi.org/10.1021/acs.langmuir.9b03668

    Article  Google Scholar 

  35. Zavieh, A., Espallargas, N.: The effect of friction modifiers on tribocorrosion and tribocorrosion-fatigue of austenitic stainless steel. Tribol. Int. (2017). https://doi.org/10.1016/j.triboint.2017.03.008

    Article  Google Scholar 

  36. Willenbruch, R.D., Clayton, C.R., Oversluizen, M., Kim, D., Lu, Y.: An XPS and electrochemical study of the influence of molybdenum and nitrogen on the passivity of austenitic stainless steel. Corros. Sci. (1990). https://doi.org/10.1016/0010-938X(90)90106-F

    Article  Google Scholar 

  37. Zavieh, A., Espallargas, N.: The role of surface chemistry and fatigue on tribocorrosion of austenitic stainless steel. Tribol. Int. (2016b). https://doi.org/10.1016/j.triboint.2016.07.020

    Article  Google Scholar 

  38. Clayton, C.R.: A bipolar model of the passivity of stainless steel: the role of Mo addition. J Electrochem. Soc. (1986). https://doi.org/10.1149/1.2108451

    Article  Google Scholar 

  39. Liu, Y., Shen, L.: From langmuir kinetics to first- and second-order rate equations for adsorption. Langmuir (2008). https://doi.org/10.1021/la801839b

    Article  Google Scholar 

  40. Nalam, P.C., Pham, A., Veronica Castillo, R., Espinosa-Marzal, R.M.: Adsorption behavior and nanotribology of amine-based friction modifiers on steel surfaces. J. Phys. Chem. C (2019). https://doi.org/10.1021/acs.jpcc.9b02097

    Article  Google Scholar 

Download references

Acknowledgements

The authors would like to acknowledge the financial support from the M-ERA.NET GreenCOAT project with Project Number 4153 as well as the financial support from The Research Council of Norway. Norwegian Micro- and Nano-fabrication facility, NorFab, is also acknowledged for providing the characterization facilities.

Funding

The project is funded by The Research Council of Norway in the form of M-ERA.NET GreenCOAT project with Project Number 4153.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to H. Khanmohammadi.

Ethics declarations

Conflict of interest

The authors declare that they have no known competing financial interests that could have influence on the work reported in this paper.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Electronic supplementary material 1 (DOCX 168 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Khanmohammadi, H., Wijanarko, W. & Espallargas, N. Ionic Liquids as Additives in Water-Based Lubricants: From Surface Adsorption to Tribofilm Formation. Tribol Lett 68, 130 (2020). https://doi.org/10.1007/s11249-020-01377-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s11249-020-01377-8

Keywords

Navigation