Exceptional Electrical Conductivity and Fracture Resistance of 3D Interconnected Graphene Foam/Epoxy Composites

Abstract

Cellular-structured graphene foam (GF)/epoxy composites are prepared based on a three-step fabrication process involving infiltration of epoxy into the porous GF. The three-dimensional (3D) GF is grown on a Ni foam template via chemical vapor deposition. The 3D interconnected graphene network serves as fast channels for charge carriers, giving rise to a remarkable electrical conductivity of the composite, 3 S/cm, with only 0.2 wt % GF. The corresponding flexural modulus and strength increase by 53 and 38%, respectively, whereas the glass transition temperature increases by a notable 31 °C, compared to the solid neat epoxy. The GF/epoxy composites with 0.1 wt % GF also deliver an excellent fracture toughness of 1.78 MPa·m(1/2), 34 and 70% enhancements against their "porous" epoxy and solid epoxy counterparts, respectively. These observations signify the unrivalled effectiveness of 3D GF relative to 1D carbon nanotubes or 2D functionalized graphene sheets as reinforcement for polymer composites without issues of nanofiller dispersion and functionalization prior to incorporation into the polymer.

High stiffness nano-composite fibres from polyvinylalcohol filled with graphene and boron nitride

“…This value is higher than the maximum conductivity observed in most papers describing graphene-filled composites which tend to fall in the range 10 -2 -10 S/m [refs [86][87][88][89][90][91][92][93][94]], although at least one paper described conductivities as high as 300 S/m. [95] In addition, this is considerably higher than the best results reported for most nanotube-filled composites. [96] For the lowest volume fractions, the conductivity was unmeasurably low.…”

Synthesis of Carbon Nanofibers with Maghemite via a Modified Sol-Gel Technique

“…CNFs, as well as the multiwalled nanotubes (MWNTs) and the singlewalled nanotubes (SWNTs), are the most common components of the nanocomposites [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Industrial products made of reinforced polymers demand improvement of the mechanical properties to preserve the structural integrity and the electrical conductivity to dissipate static electricity [16]. However, the above-mentioned carbon nanostructures differ considerably in terms of morphology, size, and price.…”

Temperature dependent compressive behavior of graphene mediated three-dimensional cellular assembly

“…due to its exceptional mechanical [10][11][12][13], thermal [14,15], electrical [16] and optical [17] characteristics. The most popular ways to synthesize graphene on mass scale production are chemically reduced graphene oxide (rGO) [18] and chemical vapor deposition (CVD) [10].…”

“…It also demonstrated a feasibility to fabricate three-dimensional network [11]. Three-dimensional network of graphene comprised of single layer graphene in the form of open cell foam [22,23] presents a lightest bulk material with additional benefit of harnessing mechanical properties for packaging and cushioning of smart electronic systems.…”