Graphene reinforced carbon fibers

Abstract

The superlative strength-to-weight ratio of carbon fibers (CFs) can substantially reduce vehicle weight and improve energy efficiency. However, most CFs are derived from costly polyacrylonitrile (PAN), which limits their widespread adoption in the automotive industry. Extensive efforts to produce CFs from low cost, alternative precursor materials have failed to yield a commercially viable product. Here, we revisit PAN to study its conversion chemistry and microstructure evolution, which might provide clues for the design of low-cost CFs. We demonstrate that a small amount of graphene can minimize porosity/defects and reinforce PAN-based CFs. Our experimental results show that 0.075 weight % graphene-reinforced PAN/graphene composite CFs exhibits 225% increase in strength and 184% enhancement in Young’s modulus compared to PAN CFs. Atomistic ReaxFF and large-scale molecular dynamics simulations jointly elucidate the ability of graphene to modify the microstructure by promoting favorable edge chemistry and polymer chain alignment.

Manufacturing Pitch and Polyethylene Blends-Based Fibres as Potential Carbon Fibre Precursors

“…Manufacturing carbon fibres using pitch, which, along with synthetic polymers, is abundant, should reduce material costs, allowing for the wider use of carbon fibres. When compared to the high cost of PAN-based fibres, the mechanical performance of such cheap and readily available materials, such as lignin, has been explored but has been found to be inadequate [ 9 ], while carbon fibres are lightweight with excellent mechanical properties [ 10 ]. Textile-grade polyethylene is chemically simple and attractive as a precursor for carbon fibre production.…”

Hierarchically Structured Composite Fibers for Real Nanoscale Manipulation of Carbon Nanotubes

“…[39,40] PAN polymer in nitrogen undergoes a cyclization of the nitrile group process at elevated temperature (e.g., treatment of stabilization and carbonization), which is crucial for making PAN-based carbon fibers. [41] An increase in activation energy during this treatment leads to more stabilized and high-performance carbon networking. [42] For the composite fibers, there was a monoclinic increase in activation energy values with higher layer numbers ( Figure S10 and Table S4, Supporting Information).…”

Computational study of the effect of core–skin structure on the mechanical properties of carbon nanofibers

“…The mechanical properties of CNFs with and without the graphitic skin layer are investigated in this study using large-scale molecular dynamics (MD) simulations. This computational technique has been successfully applied to analysis of chemical reactions leading to the formation of carbon fiber microstructure from molecular precursors [25][26][27][28][29][30][31][32], oxidation of carbon fibers [33], as well as the elementary processes involved in mechanical deformation of carbon fibers [27,28,[34][35][36][37]. The high computational cost of MD simulations, however, prevents application of this technique for direct evaluation of the mechanical properties of fibers with heterogeneous microstructure, such as the ones of core-skin carbon fibers.…”

“…The tensile testing simulations are performed with a more computationally expensive [43] ReaxFF interatomic potential [29,44,45], which provides a more realistic, as compared to the AIREBO-M potential, description of the bond rearrangement and scission during the irreversible (plastic) deformation and fracture (see Supplementary Information for additional discussion of problems preventing the use of AIREBO-M in the simulations of fracture of carbon nanofibers). The ReaxFF force field used in this paper is parameterized for C/H/O/N chemistry [29] and has been successfully applied to simulation of different steps in the carbon fiber formation [28][29][30][31].…”