Ultrahigh Performance Supercapacitor from Lacey Reduced Graphene Oxide Nanoribbons

High performance lacey reduced graphene oxide nanoribbons (LRGONR) were chemically synthesized. Holes created during the LRGONR synthesis not only enhanced the electrolytic accessibility but destacked all the graphene layers through protrusion at edge planes and corrugation in individual graphene. LRGONR in a supercapacitor cell showed ultrahigh performance in terms of specific capacitance and capacity retention. Consistently in aqueous, nonaqueous, and ionic electrolytes, LRGONR symmetric supercapacitor exhibited exceptionally high energy/power density, typically 15.06 W h kg^–1/807 W kg^–1 in aqueous at 1.7 A g^–1, 90 W h kg^–1/2046.8 W kg^–1 in nonaqueous at 1.8 A g^–1, and 181.5 W h kg^–1/2316.8 W kg^–1 in ionic electrolyte at ∼1.6 A g<sup>–1