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Title: The synthesis and electrical transport properties of carbon/Cr 2 GaC MAX phase composite microwires
While MAX phases offer an exotic combination of ceramic and metallic properties, rendering them a unique class of materials, their applications remain virtually hypothetical. To overcome this shortcoming, a sol–gel based route is introduced that allows access to microwires in the range of tens of micrometers. Thorough structural characterization through XRD, SEM, EDS, and AFM demonstrates a successful synthesis of carbonaceous Cr 2 GaC wires, and advanced low temperature electronic transport measurements revealed resistivity behavior dominated by amorphous carbon. The tunability of electronic behavior of the obtained microwires is shown by a halide post-synthesis treatment, allowing purposeful engineering of the microwires’ electrical conductivity. Raman studies revealed the polyanionic nature of the intercalated halides and a slow decrease in halide concentration was concluded from time-dependent conductivity measurements. Based on these findings, the process is considered a viable candidate for fabricating chemiresistive halogen gas sensors.  more » « less
Award ID(s):
2129412
PAR ID:
10330556
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
14
Issue:
3
ISSN:
2040-3364
Page Range / eLocation ID:
744 to 751
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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