A redox-active organic molecular electrode is prepared for supercapacitors. Benzo[1,2-b: 4,5-b'] dithiophene-4,8-dione (BDTD), planar molecule with fused heteroaromatic structure, has been adsorbed on conductive reduced graphene oxide (rGO) by pi-pi interactions to form a 3D interconnected and functionalized xerogel (BDTD-rGO). Because the five-membered aromatic heterocycle is more electron-rich than the six-membered aromatic ring, which enlarges the electronic interaction between the BDTD molecule and the conjugated graphene network and accordingly reduce the solubility of BDTD molecule in electrolyte. As a result, the optimized BDTD-rGO electrodes achieve specific capacitance of 360 F g(-1) at 1 Ag-1, with ultra-long cycle life of 96.4% after 10,000 cycles, and even 80% after 50,000 cycles at 5 A g(-1) in 1 M H2SO4. Furthermore, the asymmetric supercapacitor (ASC), which is assembled by using the BDTD-rGO as the negative electrode and lamellar holey graphene hydrogel (LGH) as the positive electrode respectively, exhibits better energy storage performance. (C) 2019 Elsevier Ltd. All rights reserved.