A novel organic molecule electrode based on organic polymer functionalized graphene for supercapacitor with high-performance

Organic synthesis strategy can tune electrochemical behavior of organic molecules by molecular level design, which can offer more material choices for sustainable supercapacitors. Herein, an organic polymer (Poly-perylene-3,4,9,10-tetracarboxydiimide-anthraquinone, PPA) is designed and synthesized as an electrode material that can achieve Faraday reaction with 4 electron transfers in a structural unit. When the PPA is directly used as electrode material, the specific capacitance can be up to 245 F g(-1) at 5 mV s(-1) within a more negative potential. Furthermore, PPA is modified on reduced graphene oxide (rGO) to prepare an Organic Molecule Electrode (OME, PPA/rGO-1), which can reach higher specific capacitance (604 F g(-1) at 5 mV s(-1)) with good cycle stability (capacitance retention of 69.9% at 5 A g(-1), over 10,000 cycles). Besides, a 2,6-dihydroxynaphthalene (DN) modified graphene hydrogel (GH) is prepared as positive electrode to match with resultant OME for fabricating an asymmetrical supercapacitor (ASC). The device can deliver an energy density of similar to 20 Wh kg(-1). Two ASCs (in series) light 40 Light Emitting Diodes (LEDs), suggesting a potential application.

Automated summary

Organic synthesis strategy is used to tune the electrochemical behavior of organic molecules, offering more material choices for sustainable supercapacitors. A designed and synthesized organic polymer is found to achieve Faraday reaction with 4 electron transfers and exhibit high specific capacitance and good cycle stability. A graphene hydrogel is also prepared as a positive electrode for fabricating an asymmetrical supercapacitor. The resulting device shows promising potential with high energy density and good performance.