Carbon foam@reduced graphene oxide scaffold grown with polyaniline nanofibers for high performance symmetric supercapacitor

To overcome the low capacitance of carbon foam and achieve a high utilization of polyaniline (PANI) pseudocapacitance, graphene nanosheets are filled into carbon foam framework to form a scaffold, and subsequently growing PANI nanofibers to prepare a ternary composite. In this material, carbon foam provides three-dimensional macroporous conductive framework, graphene nanosheets on the carbon foam framework support the deposition of PANI and increase the PANI loading, while much PANI nanofibers contribute a high pseudocapacitance. Therefore, this rationally designed ternary composite not only achieves a high PANI loading of 85.5%, but also exhibits a high specific capacitance and a high utilization of PANI capacitance. As self-supporting electrodes in a symmetrical two-electrode supercapacitor, a high capacitance of 868.5 F g(-1) is achieved, in which, the capacitance contributed by PANI reaches 1003 F g(-1), more than a half of its theoretical value, furthermore, the capacitance retention is 94.1% after 2000 cycles at 10 A g(-1). The design principle of this ternary composite is simple and facile, which can be extended to prepare other nanocomposites containing metal oxides, sulfides, etc. for potential electrochemical applications. (c) 2018 Elsevier Ltd. All rights reserved.