Next Article in Journal
Characterization of High-Power Turbomachinery Tilting Pad Journal Bearings: First Results Obtained on a Novel Test Bench
Next Article in Special Issue
Tribological Performance of Phosphonium Ionic Liquids as Additives in Lithium Lubricating Grease
Previous Article in Journal
Effect of Surface Texturing on Cast Iron Reciprocating against Steel under Cyclic Loading in Boundary and Mixed Lubrication Conditions
Article Menu
Issue 1 (March) cover image

Export Article

Open AccessArticle
Lubricants 2018, 6(1), 3; https://doi.org/10.3390/lubricants6010003

Testing of WS2 Nanoparticles Functionalized by a Humin-Like Shell as Lubricant Additives

1
Institute of Nanotechnology and Advanced Materials & Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
2
Department of Science, Holon Academic Institute of Technology, 52 Golomb St., P.O. Box 305, Holon 5810201, Israel
*
Authors to whom correspondence should be addressed.
Received: 2 November 2017 / Revised: 1 January 2018 / Accepted: 3 January 2018 / Published: 4 January 2018
(This article belongs to the Special Issue Novel Lubricant Additives)
Full-Text   |   PDF [9501 KB, uploaded 4 January 2018]   |  

Abstract

Nanoparticles of transition metal dichalcogenides (TMDC) have been known to reduce friction and wear when added to oil-type liquid lubricants. Aggregation limits the ability of the nanoparticles to penetrate into the interface between the two rubbing surfaces—an important factor in friction reduction mechanisms. Doping has been successfully used to reduce agglomeration, but it must be done in the production process of the nanoparticles. The use of surface-functionalized nanoparticles is less common than doping. Nonetheless, it has the potential to reduce agglomeration and thereby improve the reduction of friction and wear. In this study, we present the results of preliminary tribological ball-on-flat tests performed with WS2 nanoparticles functionalized by a humin-like conformal shell, as additives to polyalphaolefin-4 (PAO-4) oil. We tested WS2 inorganic nanotubes (INTs) and two grades of inorganic fullerene-like nanoparticles (IFs). The shell/coating was found to improve friction reduction for IFs but not for INTs through better dispersion in the oil. The thicker the coating on the IFs, the less agglomerated they were. Coated industrial-grade IFs were found, by far, to be the best additive for friction reduction. We suggest the combination between reduced agglomeration and poor crystallinity as the reason for this result. View Full-Text
Keywords: lubricant additive; oil; nanoparticles; WS2; functionalization lubricant additive; oil; nanoparticles; WS2; functionalization
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Sade, H.; Moshkovich, A.; Lellouche, J.-P.; Rapoport, L. Testing of WS2 Nanoparticles Functionalized by a Humin-Like Shell as Lubricant Additives. Lubricants 2018, 6, 3.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Lubricants EISSN 2075-4442 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top