The characteristics of exfoliated graphite derived from three intercalation methods: gas phase intercalation of iron (III) chloride, modified Hummers method and an electrochemical technique, were compared.Despite the absence of strong oxidizers the electrochemical method produced a material which is very similar to that of the modified Hummers method in virtually every respect. These both produced a graphite oxide based material whilst the gas phase method resulted in a stage 1 intercalation compound. The different materials demonstrated very distinctive exfoliation behaviour.The gas phase material exhibits 3% mass loss during expansion but has a large amount of residual intercalant. The graphite oxide based methods result in mass loss of up to 25% in the expansion zone. For all three samples the residual impurities lead to a reduction in oxidative resistance. Once removed all samples exhibit nearly identical oxidation behaviour.All three methods delivered graphite nanoplatelets with a very high aspect ratio through considerable expansion. Surprisingly the gas phase method caused persistent residual damage. All three methods yielded a product with varying levels of basal and edge damage, but the purified Hummers material exhibited marginally more "ideal" characteristics. The simplest but still effective technique was found to be the electrochemical approach.

This study has investigated the effect of the incorporation of graphene foam (GF) into the matrix of a ternary transition-metals hydroxide containing nickel, cobalt, and manganese for optimal electrochemical performances as electrodes for supercapacitors applications. An adopted simple, low-cost co-precipitation synthesis method involved the loading a mass of the ternary metal hydroxides (NiCoMn-TH) onto various GF mass loading so as to find ints effect on the electrochemical properties of the hydroxides. Microstructural and chemical composition of the various composite materials were investigated by employing scanning/transmission electron microscopy (SEM/TEM), x-ray diffraction (XRD), Raman spectroscopy, and N2 physisorption analysis among others. Electrochemical performances of the NiCoMn-TH/200 mg GF composite material evaluated in a three-electrode system using 1 M KOH solution revealed a maximum specific capacity around 178.6 mAh g−1 compared to 76.2 mAh g−1 recorded for the NiCoMn-TH pristine material at a specific current of 1 A g−1. The best mass loading of GF nanomaterial (200 mg GF), was then utilised as a positive electrode material for the design of a novel hybrid device. An assembled hybrid NiCoMn-TH/200 mg GF//CSDAC device utilizing the NiCoMn-TH/200 mg GF and activated carbon derived from the cocoa shell (CSDAC) as a positive and negative electrode, respectively, demonstrated a sustaining specific capacity of 23.4 mAh g−1 at a specific current of 0.5 A g−1. The device also yielded sustaining a specific energy and power of about 22.32 Wh kg−1 and 439.7 W kg−1, respectively. After a cycling test of over 15,000 cycles, the device could prove a coulombic efficiency of ~ 99.9% and a capacity retention of around 80% within a potential range of 0.0–1.6 V at a specific current of 3 A g−1. These results have demonstrated the prodigious electrochemical potentials of the as-synthesized material and its capability to be utilized as an electrode for supercapacitor applications.