Diamond-Like Carbon: A Surface for Extreme, High-Wear Environments

Abstract

In this study, we present an in-depth characterization of a diamond-like carbon (DLC) film, using a range of techniques to understand the structure and chemistry of the film both in the interior and particularly at the DLC/air surface and DLC/liquid interface. The DLC film is found to be a combination of sp<sup>2</sup> and sp<sup>3</sup> carbon, with significant oxygen present at the surface. The oxygen seems to be present as OH groups, making the DLC somewhat hydrophilic. Quartz-Crystal Microbalance (QCM) isotherms and complementary neutron reflectivity data indicate significant adsorption of a model additive, bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) surfactant, onto the DLC from water solutions and indicate the adsorbed film is a bilayer. This initial study of the structure and composition of a model surfactant is intended to give a clearer insight into how DLC and additives function as antiwear systems.

Metadata

Authors/Creators:

Sharifi, N. https://orcid.org/0000-0002-4157-097X
Smith, H. https://orcid.org/0000-0002-3389-6259
Madden, D. https://orcid.org/0000-0002-4159-6547
Kehoe, T.
Wu, G. https://orcid.org/0000-0003-0795-8898
Yang, L. https://orcid.org/0000-0003-0935-3921
Welbourn, R.J.L. https://orcid.org/0000-0002-4254-5354
Fernandez, E.G. https://orcid.org/0000-0001-6042-4364
Clarke, S.M. https://orcid.org/0000-0001-5224-2368

© 2023 The Authors. Published by American Chemical Society. This is an open access article under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited.

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