Synthesis and Exploration of Graphene Bubbles for Supercapacitor Electrodes

We report the synthesis of graphene bubbles by CVD method using metal supported (iron, copper and bimetallic iron/copper) mesoporous MCM-41 catalysts. Growth of graphene bubbles was achieved using isobutane gas as the carbon source at the temperature of 900°C. The metal doped MCM-41 shows a higher surface area of 1380 m2/g with a larger pore diameter of 6 nm. The resulting graphene-like structure from this catalyst showed a higher specific surface area of 400 m2 g−1 with bubble morphology. The graphene bubbles from Fe and Fe/Cu are of multilayered graphitic structure. MnO2 is then deposited onto the graphene surface using electrophoretic deposition method. The electrodes prepared from Cu-GB, Fe-GB and Fe/Cu-GB showed specific capacitances of 228, 257 and 327 F g−1 with energy densities of 18, 16 and 22 Wh Kg−1 respectively at the scan rate of 100 mV/sec. The high performance of the graphitic layers is attributed to the high surface area and its unique bubble nature.