Preparation of highly expanded graphene with large surface area and its additional conductive effect for EDLC performance
Expanded graphene (EG) has been produced using fast oxidation/intercalation process. The as prepared EG were then used as conductive additive to study the electrochemical properties of activated carbon based electric double layered supercapacitors (EDLCs). The physiochemical properties of EG were studied using scanning electron microscopy, Raman spectroscopic techniques, atomic force microscopy and energy dispersive X-ray analysis. The electrochemical properties were studied using charge/discharge cyclic voltammetry and electrochemical impedance spectroscopy. All the electrochemical tests were carried out in 1 M, TEA BF4 in acetonitrile as a suitable electrolyte for our AC based supercapacitors. Electrochemical test reveals that EG greatly affect the conductivity of the ions through the AC/EG interface. The specific capacitance remains the same for smaller values of EG in the composites electrodes. These results also evident the optimum loading of graphene in the future graphene based EDLCs.
KeywordsActivate Carbon Graphene Oxide Specific Capacitance Graphene Sheet Expand Graphene
This work was supported by the next generation secondary battery R&D program of MOTIE/KEIT. [10042575, Development of 5 kW Zn-air battery for EV and 3.3 V–1000 F pouch type high-power supercapacitor].
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