Tubular carbon nanofibers decorated with RuO2 nanorods toward flexible electrochemical capacitors

Abstract

RuO2 nanorod-decorated tubular carbon nanofibers(CNFs) are carefully fabricated by adjusting the re crystallization temperature for use in high-performance electrochemical capacitors. The tubular structured CNFs/RuO2 electrodes provide a short diffusion path for the ion transport through the inner hollow channel that allowed the maximum utilization of the active sites of the amorphous RuO2 nanomaterials at the electrode/electrolyte interface. The optimized the tubular structured CNFs/RuO2 electrodes exhibit good rate capability with a high surface capacitance, energy density, and good long-term cycling stability of 190 Fg(-1), 22 Whkg(-1), and 94% after 10,000 cycles, respectively, in an aqueous solution. The asymmetric cell presents a wide and stable operating voltage window, which greatly improves the energy density stored in the asymmetric device. In addition, there is no noticeable difference in the electrochemical properties under bent states, making it a flexible energy storage device for wearable applications. Hence, flexible super capacitors using CNFs/RuO2 electrodes with the tubular structure show low resistance, high capacitance, good rate retention, and excellent cycle stability, making it a promising material for energy storage applications. (c) 2022 Elsevier B.V. All rights reserved.