ABSTRACT
Graphene comprises a single layer of sp2-hybridized carbon atoms creating a 2D hexagonal lattice; as a unique monolayer crystal sheet, graphene displays a room-temperature quantum Hall eect, and it is a fundamental building block of graphite, nanotubes, and fullerenes. Although the rst experimental eort on graphene started as early as 1962 (Boehm et al. 1962), individual graphene had not been isolated until 2004 by Geim and Novoselov (Novoselov et al. 2004, 2005, 2007; Zhang et al. 2005) using a scotch tape method. Graphene has attracted enormous interest due to its exceptional properties-Young’s modulus 1 TPa, fracture strength 130 GPa, and higher electrical/ thermal conductivities than copper (Geim and Novoselov 2007; Balandin et al. 2008; Kuilla et al. 2010). Compounding graphene with other materials is a major means to harvest its striking properties, such as fabrication of polymer/graphene composites, because most polymers lack electrical and thermal functionalities and sucient mechanical strength. Nevertheless, pristine graphene is not well mixable with polymers due to its inert surface. Hence, reduced graphene oxide has been widely used, but it is limited by the low structural integrity implying unsatisfactory electrical and thermal conductivities. As a result, GnPs (also called graphene nanoplatelets) consisting of a fewlayer graphene have been developed, which feature cost-eectiveness, high structural integrity, and modied surface for compounding with other materials (Zaman et al. 2012a,b).
