Chelation Drives Surface Substitution in Hybrid-MXenes.

Authors

Vikash Khokhar, Young-Hwan Kim, Abu Rashed Md Shawon, Fatemeh Karimi, Danial Zangeneh, Yongqiang Cheng, Chang Liu, Murillo Longo Martins, Alexander S Filatov, Robert F Klie, Aaron J Rossini, John S Anderson, Dmitri V Talapin, De-En Jiang

Published in

Angewandte Chemie (International ed. in English). Pages e6432447. Jul 20, 2026. Epub Jul 20, 2026.

Abstract

Hybrid organic-inorganic MXenes (h-MXenes) offer a versatile platform for tailoring the surface chemistry of two-dimensional transition-metal carbides and nitrides through covalently bound organic ligands. Although monodentate amido/imido functionalization has been demonstrated previously, chelating ligand binding has remained unexplored. Here, we report the synthesis of Ti₃C₂(en)_x h-MXenes via substitution of Br terminations in Ti₃C₂Br₂ with deprotonated ethylenediamine (en). By varying the amount of n-BuLi used for en deprotonation, the surface coordination evolves from predominantly monodentate to bidentate binding. This transition is evidenced by a contraction of the interlayer spacing and attenuation of the ─NH₂ signal in x-ray photoelectron spectroscopy. Solid-state NMR reveals that bidentate coordination dominates when 4 equiv. of n-BuLi is employed, while inelastic neutron scattering, supported by simulated vibrational spectra, provides independent confirmation of the bidentate binding motif. Density functional theory calculations show that bidentate en is significantly more stable than monodentate configurations for replacing Br terminations. Ab initio molecular dynamics further reveal dynamic surface chemistry involving proton transfer, β-H elimination, surface imine-Ti bond formation, and partial reversion to monodentate coordination. These findings establish ligand denticity as a new design parameter for engineering MXene surface chemistry and tuning material properties.

PMID:
42473854
Bibliographic data and abstract were imported from PubMed on 20 Jul 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.