Influence of X Elements on the Tribological Properties and Surface Chemistry of MXene Atomic Layers.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40481806.
- Also identified by DOI 10.1021/acs.nanolett.5c02270 and PMC identifier 12239071.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
MXenes, a class of two-dimensional (2D) transition-metal carbides, nitrides, and carbonitrides, exhibit promising tribological properties at the nanoscale. However, the influence of X elements on the surface chemistry of MXene atomic layers remains underexplored. Here, we investigate how nitrogen in the Ti<sub>3</sub>CN atomic layer modifies its nanotribological behavior compared to Ti<sub>3</sub>C<sub>2</sub>. Using friction force microscopy and peak force quantitative nanomechanics , we find that Ti<sub>3</sub>CN exhibits a notable increase in friction along with higher adhesion and energy dissipation, which we attribute to enhanced hydroxyl termination, stronger surface dipole interactions, and hydrogen bonding. X-ray photoelectron spectroscopy further reveals that nitrogen incorporation leads to greater electron withdrawal from titanium atoms, resulting in a higher oxidation state and altered surface chemical functionality. These results provide mechanistic insight into how X-element chemistry influences the tribological performance of MXenes, highlighting the importance of surface composition in designing 2D materials for specific applications.