High energy-density organic supercapacitors based on optimum matching between GNS/aMWCNT@polyaniline nanocone arrays cathode and GNS/aMWCNT@poly(1,5-diaminoanthraquinone) nanoparticles anode

•Unique GNS/aMWCNT@PANI nanocone arrays are synthesized by an interfacial polymerization.•Optimal oASC matching GNS/aMWCNT@PDAA anode with GNS/aMWCNT@PANI cathode is achieved.•As-assembled oASC exhibits superhigh energy density of 96.9 Wh kg−1.

Nowadays, high energy density is greatly imperative for supercapacitor technologies, which focus on both high-performance electrodes and assembling techniques. Here, we synthesized a promising cathode of graphene/acid-treated carbon nanotubes (GNS/aMWCNT)-supported polyaniline nanocone arrays by an interfacial polymerization, which achieves high specific capacitance of 299 F g−1 in 1 M tetraethylammonium tetrafluoroborate-acetonitrile (Et4NBF4-AN) with the potential window of −0.6 to 0.8 V (vs. Ag/Ag+). Matching it with GNS/aMWCNT-supported poly(1,5-diaminoanthraquinone) nanoparticles anode, the organic asymmetric supercapacitors (oASCs) are perfectly fabricated. The oASC with anode/cathode mass ratio of 1/1 delivers the highest energy density of 96.9 Wh kg−1, excellent rate capability (retain 65.6 Wh kg−1 even at 65.7 kW kg−1) and superior cycling stability (94.2% retention after 5000 cycles), which is superior or comparable to other π-conjugated polymers-based organic supercapacitors.

Graphical abstractDownload high-res image (84KB)Download full-size image