Graphene fiber

There are three main methods to produce CNT-based macroscopic fibers wet spinning, forest drawing and direct spinning from CVD. These are shown schematically in Fig. 8.9. So far, only the first has been applied to produce graphene fibers. 

Cong H-P, Ren X-C, Wang P, Yu S-H. Wet-spinning assembly of continuous, neat, and macroscopic graphene fibers. Sci Rep [Internet]. 2012 Aug 30 2. Available from http //dx.doi.org/10.1038/srep00613... 

Fig. 3.13 Macroscopic neat GO fibers and chemically reduced gn hene fibers, a four-metre-long GO fiber wound on a Teflon drum (diameter, 2 cm). SEM image of the fiber (b), and its typical knots (c). d The fracture morphology of GO fiber after tensile tests. The surface winkled morphology (e) and the tighten knot (f) of graphene fiber, g A Chinese character pattern knitted in the cotton network using two graphene fibers, h A mat of graphene fibers woven together with cotton threads. Reproduced with permission from [117]. Copyright 2011 Macmillan Publishers Limited...

R. Jalili, S.H. Aboutalebi, D. Esrafilzadeh, R.L. Shepherd, J. Chen, S. Aminorroaya-Yamini, K. Konstantinov, A.I. Minett, J.M. Razal, G.G. Wallace, Scalable one-step wet-spinning of graphene fibers and yams from liquid crystalline dispersions of graphene oxide towards multifunctional textiles. Adv. Funct. Mater. 23, 5345-5354 (2013)... 

Li, X. M., T. S. Zhao, Q. Chen et al. 2013. Flexible all solid-state supercapacitors based on chemical vapor deposition derived graphene fibers. Physical Chemistry Chemical Physics 15 17752-17757. 

Compared to PAN and pitch-based carbon fiber, the morphology of VGCF is unique in that the graphene planes are more preferentially oriented around the axis... 

Physisorption measurements showed that carbon nanomaterials exhibit rather meso- and macroporous structures (maximum micropore fraction, 15% see Table 2.1). The lowest specific surface area was measured with the platelet fiber catalyst exhibiting slightly more than 100 m2/g. The Co/HB material offers 120 m2/g of surface area, and the highest BET value was determined with the Co/ MW catalyst featuring nearly 290 m2/g. Carbon nanomaterials, though, are not really porous, as the space between the graphene layers is too small for nitrogen molecules to enter. The only location of adsorption is the external surface of the nanomaterials and the inner surface of the nanotubes. 

Fig. 8.2 Plot of increase in modulus against volume fraction for a wide variety of nanocarbon/poly-mer systems. Volume fractions calculated from reported mass fractions assuming specific gravities of 1.8, 2.1 and 1 for CNT, graphene and matrix, respectively. Short fiber data from [16] and [17]. Moduli of individual layer graphene (lTPa) and reduced-graphene oxide (250GPa) included for reference.

---