Application of biomass-derived flexible carbon cloth coated with MnO2 nanosheets in supercapacitors

Abstract Successful application of inexpensive energy storage devices lies in the exploitation of fabrication approaches that are based on cost-efficient materials and that can be easily scaled up. Here, inexpensive textile weaved by natural flax fiber is selected as raw material in preparing flexible and binder-free electrode material for supercapacitors. Although carbon fiber cloth obtained from the direct carbonization of flax textile exhibits a low specific capacitance of 0.78 F g−1, carbon fiber cloth electrode shows a very short relaxation time of 39.1 m s and good stability with almost 100% capacitance retaining after 104 cycles at 5 A g−1. To extend the application of the resulting carbon cloth in supercapacitor field, a layer of MnO2 nanosheets is deposited on the surface of carbon fiber via in situ redox reaction between carbon and KMnO4. The specific capacitance of MnO2 reaches 683.73 F g−1 at 2 A g−1 and still retains 269.04 F g−1 at 300 A g−1, indicating the excellent rate capacitance performance of the carbon cloth/MnO2 hybrids. The present study shows that carbon cloth derived from flax textile can provide a low-cost material platform for the facile, cost-efficient and large scale fabrication of binder-free electrode materials for energy storage devices.