Understanding the role of tungsten species in diamond-like carbon coatings for enhanced interaction with ionic liquids

Arshad, Muhammad Shahid (author), Čoga, Lucija (author), Kovač, Janez (author), Geue, Thomas M. (author), Cruz, Sandra M.A. (author), Kalin, Mitjan (author)

This study investigated the impact of tungsten species in tungsten-doped diamond-like carbon (WDLC) coatings on their interactions with ionic liquids (ILs). Using analytical techniques such as in-situ neutron reflectometry, time-of-flight secondary ion mass spectrometry, and Raman spectroscopy, we examined the adsorption mechanism of tributylmethylphosphonium dimethylphosphate on WDLC and undoped hydrogenated DLC (hDLC) coatings. These techniques provide high-resolution insights into the molecular interactions, revealing that tungsten doping enhances the formation of tungsten carbide and tungsten oxides. These species facilitate the dissociation of dimethylphosphate anions, forming a robust 0.75 nm-thick tungsten phosphate layer on the WDLC surfaces. This layer, which adheres strongly even after cleaning, underscores the role of tungsten in enhancing the effectiveness and lubrication properties of WDLC coatings with ILs.

• Language: English
• Keywords: WDLC coatings, adsorption mechanism, ionic liquid, neutron reflectometry, measurements
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 11 str.
• Numbering: Vol. 201, art. 110220
• PID: 20.500.12556/RUL-165617
• UDC: 543.424.2
• ISSN on article: 0301-679X
• DOI: 10.1016/j.triboint.2024.110220
• COBISS.SI-ID: 218359043
• Publication date in RUL: 10.12.2024

Record is a part of a journal

• Title: Tribology international
• Shortened title: Tribol. int.
• Publisher: Elsevier
• ISSN: 0301-679X
• COBISS.SI-ID: 26558976

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.