Supercapacitors based on (carbon nanostructure)/PEDOT/(eggshell membrane) electrodes

The feasibility of wearable electronics depends on the development of reliable energy storage devices that could combine high energy density to mechanical flexibility. A significant step towards this goal would be the preparation of supercapacitors prepared on truly flexible supports, which could present an adequate balance of Faradaic and non-Faradaic charge-discharge mechanisms. In this work, we have examined the performance of supercapacitors made by the incorporation of PEDOT, a conducting polymer, and carbon nanostructures (graphene nanoplatelets and two types of carbon nanotubes) on electrodes based on eggshell membranes. These biological substrates, which are flexible and present resilient mechanical properties, have a characteristically high porosity that favors the in situ polymerization of PEDOT. The final devices exhibit a very good electrochemical performance (such as a low IR drop, a good cyclability and a high capacitive retention, which after 2000 uses suffers a reduction of only 10% on its value), and an areal capacitance of the order of 39.6 mF cm–2.