AQDS-guided growth of nanocilia-like polyaniline on graphene nanofiber as cathode material for high-performance asymmetric supercapacitors

Reduced graphene oxide nanofiber (rGONF) modified by anthraquinone-1,5-disulfonate (AQDS) (AQDS-rGONF) was prepared by one-step hydrothermal reaction , and nanocilia-like polyaniline (PANI) grew uniformly on the surface of rGONF under the guidance of AQDS as a starting point of polymerization to fabricate successfully PANI/AQDS-rGONF composite. The results showed that PANI/AQDS-rGONF composite had a larger specific capacitance of 511 F/g than PANI/rGONF composite of 360 F/g or PANI of 312 F/g at a current density of 8 mA/cm 2 , and a greater electrochemical stability with the specific capacitance retention of 82.4% than PANI/rGONF of 63.2% or PANI of 52.2% after 2000 cycles, which were closely related to the synergistic effects of special nanocilia-like structure, large specific surface area, rGONF as a supporting skeleton and AQDS as a “bridge”. In addition, an asymmetric supercapacitor based on PANI/AQDS-rGONF composite as cathode was assembled, which exhibited a high energy density of 17.9 Wh/kg at a power density of 907 W/kg.