Abstract:
:Graphene oxide (GO), the main precursor of graphene-based materials made by solution processing, is known to be very stiff. Indeed, it has a Young's modulus comparable to steel, on the order of 300 GPa. Despite its very high stiffness, we show here that GO is superflexible. We quantitatively measure the GO bending rigidity by characterizing the flattening of thermal undulations in response to shear forces in solution. Characterizations are performed by the combination of synchrotron X-ray diffraction at small angles and in situ rheology (rheo-SAXS) experiments using the high X-ray flux of a synchrotron source. The bending modulus is found to be 1 kT, which is about two orders of magnitude lower than the bending rigidity of neat graphene. This superflexibility compares with the fluidity of self-assembled liquid bilayers. This behavior is discussed by considering the mechanisms at play in bending and stretching deformations of atomic monolayers. The superflexibility of GO is a unique feature to develop bendable electronics after reduction, films, coatings, and fibers. This unique combination of properties of GO allows for flexibility in processing and fabrication coupled with a robustness in the fabricated structure.
journal_name
Proc Natl Acad Sci U S Aauthors
Poulin P,Jalili R,Neri W,Nallet F,Divoux T,Colin A,Aboutalebi SH,Wallace G,Zakri Cdoi
10.1073/pnas.1605121113subject
Has Abstractpub_date
2016-10-04 00:00:00pages
11088-11093issue
40eissn
0027-8424issn
1091-6490pii
1605121113journal_volume
113pub_type
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