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Title: First-principles study of MXene properties with varying hydrofluoric acid concentration
With varying hydrofluoric acid (HF) concentrations under three etching conditions, we presented a comparative study of the effects of both the ordered and randomly ternary mixed terminated Ti3C2Tx surfaces with a wide variation of O/OH/F stoichiometry on the thermodynamic stability and electronic properties. Regardless of the HF concentration, an OH-rich surface is found to be thermodynamically stable and the electrical conductivity of Ti3C2Tx is substantially affected by the OH concentration. The charge density difference and electron localization function demonstrated a significant electron localization at the hydroxyl group on the O/OH/F mixed terminated surface, which could yield a locally induced dipole on the surface that renders favorable reaction sites on the functionalized surface. In addition, a large tunability in the work function (ΔΦ ∼ 3.5 eV) is predicted for Ti3C2Tx. These findings provide a pathway for strategically tuning the electronic and structural properties of Ti3C2 MXenes etched with HF.  more » « less
Award ID(s):
2117956
PAR ID:
10548389
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Cell Press
Date Published:
Journal Name:
iScience
Volume:
27
Issue:
2
ISSN:
2589-0042
Page Range / eLocation ID:
108784
Subject(s) / Keyword(s):
Inorganic chemistry, Interface science, Quantum chemistry
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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