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Title: Two-dimensional Niobium Carbide MXene, Nb 2 CT x : intrinsic and photoexcited carrier dynamics
Garnering attention for high conductivity, nonlinear optical properties, and more, MXenes are water-processable 2D materials that are considered candidates for applications in electromagnetic interference shielding, optoelectronic and photonic devices among others. Herein we investigate the intrinsic and photoexcited conductivity in Nb 2 CT x, a MXene with reported high photothermal conversion efficiency. DFT calculations show that hydroxyl and/or fluorine-terminated or is metallic, in agreement with THz spectroscopy, which reveals the presence of free charge carriers that are highly localized over mesoscopic length scales. Photoexcitation of Nb 2 CT x, known to result in rapid heating of the crystal lattice, is found to produce additional free carriers and a transient enhancement of photoconductivity. Most photoexcited carriers decay over the sub-picosecond time scales while a small fraction remain for much longer, sub-nanoseconds, times.  more » « less
Award ID(s):
2021871
PAR ID:
10523448
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
IEEE
Date Published:
ISBN:
979-8-3503-3660-3
Page Range / eLocation ID:
1 to 2
Subject(s) / Keyword(s):
Heating systems Spectroscopy Lattices Nonlinear optical devices Optical materials Photoconductivity Transient analysis
Format(s):
Medium: X
Location:
Montreal, QC, Canada
Sponsoring Org:
National Science Foundation
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