Mn₃O₄/RGO/SWCNT hybrid film for all-solid-state flexible supercapacitor with high energy density

Mn₃O₄/reduced graphene oxide/single-walled carbon nanotube flexible hybrid film with outstanding flexibility and electrochemical performance is prepared via a vacuum filtration method. The three-dimensional interconnect structure is constructed by reduced graphene oxide and single-walled carbon nanotube, and Mn₃O₄ nanoplates with pesudocapacitance are embedded into the interconnect structure. The regular interconnect structure and a synergetic effect between graphene oxide/single-walled carbon nanotube and Mn₃O₄ make the Mn₃O₄/reduced graphene oxide/single-walled carbon nanotube flexible film electrode exhibit a large areal capacitance of 796 mF cm⁻². All-solid-state Mn₃O₄/reduced graphene oxide/single-walled carbon nanotube flexible supercapacitor is prepared by using the hybrid film as electrodes and sandwiching the PVA–KOH gel electrolyte, it exhibits a large area specific capacitance of 360 mF cm⁻² and the capacitance maintains 95% after 5000 charge/discharge cycles. The assembled supercapacitor exhibits both outstanding mechanical performance and a high areal energy density of 32 μW h cm⁻² at an areal power density of 0.392 mW cm⁻². The Mn₃O₄/reduced graphene oxide/single-walled carbon nanotube flexible supercapacitors exhibit significant potentiality in flexible and wearable electronics owing to their excellent flexibility, high energy density and long cycle life.