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Title: Elucidating charge transport mechanisms in cellulose-stabilized graphene inks
Solution-processed graphene inks that use ethyl cellulose as a polymer stabilizer are blade-coated into large-area thin films. Following blade-coating, the graphene thin films are cured to pyrolyze the cellulosic polymer, leaving behind an sp 2 -rich amorphous carbon residue that serves as a binder in addition to facilitating charge transport between graphene flakes. Systematic charge transport measurements, including temperature-dependent Hall effect and non-contact microwave resonant cavity characterization, reveal that the resulting electrically percolating graphene thin films possess high mobility (≈160 cm 2 V −1 s −1 ), low energy gap, and thermally activated charge transport, which develop weak localization behavior at cryogenic temperatures.
Authors:
; ; ; ; ; ; ;
Award ID(s):
2039268 1727846
Publication Date:
NSF-PAR ID:
10252953
Journal Name:
Journal of Materials Chemistry C
Volume:
8
Issue:
43
Page Range or eLocation-ID:
15086 to 15091
ISSN:
2050-7526
Sponsoring Org:
National Science Foundation
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