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Title: Fabrication of Ti 3 C 2 T x MXene Transparent Thin Films with Tunable Optoelectronic Properties

MXenes, a new class of 2D transition metal carbides and carbonitrides, show great promise in supercapacitors, Li‐ion batteries, fuel cells, and sensor applications. A unique combination of their metallic conductivity, hydrophilic surface, and excellent mechanical properties renders them attractive for transparent conductive electrode application. Here, a simple, scalable method is proposed to fabricate transparent conductive thin films using delaminated Ti3C2MXene flakes by spray coating. Homogenous films, 5–70 nm thick, are produced at ambient conditions over a large area as shown by scanning electron microscopy and atomic force microscopy. The sheet resistances (Rs) range from 0.5 to 8 kΩ sq−1at 40% to 90% transmittance, respectively, which corresponds to figures of merit (the ratio of electronic to optical conductivities,σDC/σopt) around 0.5–0.7. Flexible, transparent, and conductive films are also produced and exhibit stableRsvalues at up to 5 mm bend radii. Furthermore, the films' optoelectronic properties are tuned by chemical or electrochemical intercalation of cations. The films show reversible changes of transmittance in the UV–visible region during electrochemical intercalation/deintercalation of tetramethylammonium hydroxide. This work shows the potential of MXenes to be used as transparent conductors in electronic, electrochromic, and sensor applications.

 
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NSF-PAR ID:
10235633
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Electronic Materials
Volume:
2
Issue:
6
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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