5, 7, 12, 14-pentacenetetrone (PT), polycyclic quinone derivatives, are rich in carbonyl, which were investigated as a novel organic electrode material for supercapacitors. PT with aπconjugated system, is a flat molecule, generating strongπ-πinteractions between molecules. PT molecules were uniformly fixed on conductive reduced graphene oxide (rGO) throughπ-πinteraction by one-step solvothermal method, forming a three-dimensional cross-linked PT@rGO hydrogel. This composite structure was conducive to reducing the charge transfer resistance and promoting the Faraday reaction of electrode, which achieved the superposition of electric double-layer capacitance and pseudocapacitance. Appropriate organic molecular loading can effectively improve electrochemical performance. The optimal PT@rGO electrode material displayed the specific capacitance of 433.2 F g-1at 5 mV s-1with an excellent rate capability in 1 mol l-1H2SO4electrolyte. Finally, the fully pseudocapacitive asymmetric supercapacitor has been assembled by using PT@rGO as positive electrode and benz[a]anthracene-7,12-quinone (BAQ) modified rGO(BAQ/rGO)as negative electrode, which exhibited the good energy storage performance in a cell voltage of 1.8 V.
Keywords: electrochemical reversibility; graphene; non-covalent functionalization; organic molecule electrode; surpercapacitor.
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