shows CV curves of fct-EEM/fct-EEG at scan rates ranging from 50 mV s -1 to 1000 mV s -1 . When at a lower scan rate (< 200 mV s -1 ), a redox peak at ~0.1 V is observed and the CV curves are not symmetric, indicating that the reactions are not reversible. The redox peak fades as the scan rate increases and shapes of the CV curves exhibit quasirectangular shapes, which might be due to the fact that there is not sufficient time for the fct-EEM/fct-EEG to react at high scan rates and thus the EDL capacitance dominates.