Abstract:

The practical application of supercapacitors has been limited by the energy density, which could be effectively improved by matching the specific capacitance between the positive and negative electrode and designing an asymmetric organic supercapacitor. Herein, we synthesis activated hierarchical porous carbon (aHPC) supported polyaniline (aHPC@PANI) and aHPC supported poly(1,5-diaminoanthraquinone) (aHPC@PDAA) nanocomposites by an in-situ chemical polymerization method with aHPC as scaffolds and β-naphthalenesulfonic acid (β-NSA) as both soft-template and doping acid. As a result, both aHPC@PDAA and aHPC@PANI composites exhibit loose and porous structure with polymer nanoparticles deposited evenly on the aHPC surface, which are beneficial for the utilization and rate performance of active materials. Moreover, aHPC@PANI is used for the positive electrode, which delivers the specific capacitance of 256.7 F·g^–1 at a current density of 1 A·g^–1 (-0.6~0.8 V). And the negative electrode is based on the aHPC@PDAA, and its specific capacitance is 253 F·g^–1 at 1 A·g ^–1(–2～–0.6 V). The as-assembled aHPC@PANI//Et4NBF4-AN//aHPC@PDAA asymmetric organic supercapacitor achieves wide potential window (2.8 V), high energy density (65 W·h·kg^–1, 1.38 kW·kg^–1, based on total mass of aHPC@PANI and aHPC@PDAA), and excellent cycling stability (the capacitance retention is 90.2% after 5000 cycles).

Key words: activated hierarchical porous carbon, polyaniline, polyaminoanthraquinone, asymmetric supercapacitor, organic electrolyte