The area of the enclosed CV curve increases as the scan rate rises, suggesting good capacitive behaviour of fct-EEM/fct-EEG . The CV curves of fct-EEM/fct-EEG and EEM/EEG are compared in Figure . There is no obvious redox peak observed for the CV curve of EEM/EEG while there is one at ~ 0.1 V for fct-EEM/fct-EEG. The redox peak for fct-EEM/fct-EEG indicates that the capacitance of fct-EEM/fct-EEG consist of both pseudocapacitance and EDL capacitance.