High-performance symmetric supercapacitors based on carbon nanotube/graphite nanofiber nanocomposites

Yongsheng Zhou,Yatong Zhou,Yingchun Zhu,Pan Jin

doi:10.1038/s41598-018-27460-8

Abstract

This work reports the nanocomposites of graphitic nanofibers (GNFs) and carbon nanotubes (CNTs) as the electrode material for supercapacitors. The hybrid CNTs/GNFs was prepared via a synthesis route that involved catalytic chemical vapor deposition (CVD) method. The structure and morphology of CNTs/GNFs can be precisely controlled by adjusting the flow rates of reactant gases. The nest shape entanglement of CNTs and GNFs which could not only have high conductivity to facilitate ion transmission, but could also increase surface area for more electrolyte ions access. When assembled in a symmetric two-electrode system, the CNTs/GNFs-based supercapacitor showed a very good cycling stability of 96% after 10 000 charge/discharge cycles. Moreover, CNTs/GNFs-based symmetric device can deliver a maximum specific energy of 72.2 Wh kg−1 at a power density of 686.0 W kg−1. The high performance of the hybrid performance can be attributed to the wheat like GNFs which provide sufficient accessible sites for charge storage, and the CNTs skeleton which provide channels for charge transport.

Highlights

This work reports the nanocomposites of graphitic nanofibers (GNFs) and carbon nanotubes (CNTs) as the electrode material for supercapacitors
Since the mean diameter of GNFs are larger than CNTs, it is convenient for CNTs to attach onto GNFs surfaces
The symmetric supercapacitor displays the maximum energy density of super capacitor with 72.2 Wh kg−1 at a power density of 686.0 W kg−1, as shown in Fig. 4e, these results are much higher than many previously reported works (Table S1). These results show that CNTs/GNFs composite are promising electrode materials for electrochemical supercapacitors with high performance and excellent rate electrochemical supercapacitor

Summary

Introduction

This work reports the nanocomposites of graphitic nanofibers (GNFs) and carbon nanotubes (CNTs) as the electrode material for supercapacitors. Various nanocarbon-based materials including one-dimensional (1D) carbon nanotubes (CNTs) or graphitic nanofibers (GNFs), two- dimensional (2D) graphene nanosheets, and three-dimensional (3D) nanostructured carbon have attracted extensive attention in supercapacitors[16,18,19,20,21,22,23,24,25]. Among these materials, CNTs has superior electrical conductivity, as well as large specific surface area which can dramatically boost the supercapacitance of the carbon composites[26,27,28,29]. A kind of low-cost and environmental friendly electrode materials can be provided for high energy density supercapacitors

Methods

Results

Conclusion