RGO/MnO2/polypyrrole ternary film electrode for supercapacitor

Abstract

The binder-free electrode is expected for developing supercapacitor with high energy density. By using the good conductivity and forming-film property of PPy (Polypyrrole) and RGO (Reduced Graphene Oxide), as well as the high capacitance of MnO2 and PPy, [RGO/MnO2+PPy]10 ternary film electrode with high capacitance and good flexibility is prepared by a filtration-directed self-assembly technique. PPy nanoparticles (PPy) and MnO2 nanoparticles (MnO2) are uniformly embedded in RGO matrix constructed by the RGO nanosheets, decreasing the agglomeration of PPy and MnO2 and the reassembling of RGO nanosheets. RGO and PPy improve the conductivity, the ion diffusion rate and the charge-transfer resistance of the [RGO/MnO2+PPy]10 ternary film electrode, thus making it shows high capacitance and good flexibility. The [RGO/MnO2+PPy]10 ternary film electrode with a mass ratio of RGO:MnO2:PPy = 2:1:2 delivers the highest specific capacitance of 682 F g−1 at a scan rate of 5 mV s−1 and good cycling stability with about 86% retention of its original capacitance after 1000 consecutive cycles. The superior performance of [RGO/MnO2+PPy]10 ternary film electrode is probably ascribed to the novel film structure, the synergistic effect among PPy, RGO and MnO2 and the high packing density of PPy and MnO2.