High-performance flexible planner device featuring WS2 electrode and non-aqueous polymeric ionic electrolytes incorporated with ionic liquid and dual redox additives

Introducing redox-active species to enhance redox-activity at electrode–electrolyte interfaces, and designing the rational architecture of flexible supercapacitors comprising high-performance active materials and electrolytes with a wide potential window would be a key strategy to boost energy and power density. Herein, for the first time, we prepared an ionic liquid-based polymer electrolyte (IL/PE) by entrapping ionic liquid N-methyl-N-butyl pyrrolidinium bis (trifluoromethane sulfonyl) imide (P14TFSI)) in a polymer electrolyte Poly (diallyl dimethylammonium bis (trifluoromethane sulfonyl) imide (PDADMATFSI)) and blended with dual redox-additives (potassium iodide, KI and diphenylamine, DPA). The IL/PE with dual redox additives, demonstrates spectacular flexibility, high ionic conductivity (∼23.8 × 10−4 S cm−1), and stability in a wide potential window (∼5.9 V). A symmetrical interdigitated planner device is fabricated using dual redox-active IL/PE and flower-like WS2 electrode material. Benefiting from the synergistic effect of dual redox-active additive, the highest energy density of 47.86 µWh cm−2 at a power density of 3509 µW cm−2, and a high working potential (3 V) with excellent cycling stability upto 20,000 cycles has been achieved.