Performance dependence of electrochemical capacitor on surface morphology for vertically aligned graphene nanosheets

“Vertically aligned graphene nanosheets” are a type of graphitic carbon nanostructure with an interconnected network of perpendicularly aligned graphene nanosheets. In this study, the thin films of this material are deposited on stainless steel substrates using electron cyclotron resonance–based plasma-enhanced chemical vapor deposition. The variation of the electrochemical performance of the vertically aligned graphene nanosheets with the change in surface morphology is analyzed. The samples with different surface geometries offer different values of specific capacitances. The sample with nanopores between the graphene nanosheets of largest diameter and of most open nature delivers the highest specific electrode capacitance of 0.98 mF cm−2 (11.09 F cm−3) at a current density 0.88 mA cm−2 while the corresponding value for the sample with the smallest gap between nanosheets is of 0.49 mF cm−2 (6.67 F cm−3). The results point out at a direct correlation between surface morphology and electrochemical performance of the material.