Flexible supercapacitors based on in-situ synthesis of composite nickel manganite@reduced graphene oxide nanosheets cathode: An integration of high mechanical flexibility and energy storage

Abstract

Supercapacitors have attracted considerable attention in the context of electric vehicles, renewable energy storage, and industrial equipment. Nevertheless, further work is required to enhance the energy storage performance and improve the adaptability of supercapacitors under mechanical loads. To address these challenges, we propose a novel design strategy for composite micro-nano structures of reduced graphene oxide coated in situ growth of nickel manganite nanoarrays on the carbon fiber surface (CF@NiMn2O4@rGO). This design enables the fabrication of flexible supercapacitor electrodes with optimised electrochemical and mechanical properties. The CF@NiMn2O4@rGO cathode exhibits a synergistic effect that enhances energy storage, as evidenced by a high specific capacitance of 1003.35Fg-1 (at 10mAcm-2) and exceptional cycling stability over more than 4000 cycles. Furthermore, the flexible carbon fiber (CF) and in-situ grown nickel manganite@reduced graphene oxide (NiMn2O4@rGO) contribute to improved mechanical properties of the electrode. The assembled supercapacitor exhibits both high energy density and cycling stability. Notably, the flexible bending angle ranging from 0o to 180o has minimal impact on the energy storage performance of this flexible supercapacitor. Even under a bending angle of 180o, it successfully powers a small light bulb. This novel nanostructured material presents an innovative approach for designing flexible supercapacitors.