Fabrication of coral like carbon black/MnO2 nano composites from commercial carbon black and their application in supercapacitors
A carbon black/MnO2 nano-composite (CB/MnO2) of coral-like architecture was synthesized from a commercially available conductive carbon black (CB) using an in situ method. The morphology and structural analysis of the synthesized CB/MnO2 revealed 10 nm thick MnO2 nano-sheets grown on the CB. The MnO2 nano-sheets of poorly crystalline δ-MnO2 birnessite structure assembled into a coral-like architecture. Energy dispersive X-ray (EDX) microanalysis showed high Mn content in the composite. Electrochemical tests using the synthesized CB/MnO2 showed a specific capacitance of 946 F g−1 at a current density of 0.3 A g−1, which was much higher than that of the composites reported in the literature. Under a current density of 30 A g−1, the CB/MnO2 electrode was shown to retain a high specific capacitance after 5000 charge/discharge cycles. The results from this study demonstrate that the CB/MnO2 nano composite materials of coral-like architecture fabricated with commercially available CB and MnO2 achieved a good electrochemical performance, exhibiting promising application prospects.