The aminated beta-cyclodextrin (β-CD-N) molecules were first used to modify graphene for fabricating the hybrid film electrode (G/β-CD-N) using a method combining mild water bath heat-treatment and vacuum filtration. As compared with pure graphene film (G) and beta-cyclodextrin (β-CD) modified graphene film (G/β-CD), the prepared G/β-CD-N hybrid film exhibits better hydrophilic property, thermal stability and higher mechanical flexibility. Particularly, the G/β-CD-N hybrid film has a remarkably high areal specific capacitance (614 mF cm–2 at 0.5 mA cm–2), good mechanical flexibility (maintaining 98.2% for 1000 bending/unbending cycles) and long-term cycle stability (maintaining 96.8% for 10000 charge/discharge cycles). Moreover, the assembled G/β-CD-N based flexible and symmetric all-solid-state supercapacitor shows an excellent volumetric specific capacitance of 22.53 F cm–3 at 0.5 mA cm–2 and a high energy density of 3.13 mWh cm–3 at a power density of 0.014 W cm–3. The high comprehensive performances of the developed hybrid film electrodes can be ascribed to the combined effects of β-CD molecules and the amination process. This work provides a new approach for the fabrication of flexible supercapacitor with high performance.
Published in: "Journal of the Electrochemical Society".