High-performance supercapacitors based on the carbon nanotubes, graphene and graphite nanoparticles electrodes

L Fekri Aval,M Ghoranneviss,G Behzadi Pour

doi:10.1016/j.heliyon.2018.e00862

Abstract

In this study, the three structures of the symmetric paper supercapacitors based on the carbon nanotubes (CNTs), graphite nanoparticles (GNPs) and graphene electrodes have been fabricated. In the supercapacitors was used of polyvinyl alcohol (PVA)/phosphoric acid (H3PO4) as a gel electrolyte and the BaTiO3 film as a separator film. The carbon nanomaterials, gel electrolyte surface, and electrode films were characterized by scanning electron microscopy (SEM) and transmission electron microscope (TEM). The specific capacitance of the symmetric paper supercapacitors using charge-discharge technique and C-V curves at the voltage scan rates 20 mV/s and 150 mV/s have been investigated. The symmetric paper supercapacitor based on the CNTs electrode showed higher specific capacitance 411 F g−1, compared to GNPs and graphene supercapacitors. Also by electrochemical impedance spectroscopy, the Nyquist curves of the symmetric paper supercapacitors have been plotted. For the symmetric paper supercapacitors based on the GNPs, graphene and CNTs electrodes the equivalent series resistance (ESR) resistance was 210 Ω, 96 Ω and 101 Ω respectively. The flexible symmetric paper supercapacitor based on BaTiO3/PVA/CNTs structure denotes a new type of the flexible supercapacitor that can be applied to the soft electronic.

Highlights

Supercapacitors with high power density and storage capacity are devices for electrical energy storage
In Ref. [4] the paper supercapacitor based on carbon nanotubes (CNTs) electrodes and H3PO4/polyvinyl alcohol (PVA) gel electrolyte has been described
Self-assembled hierarchical formation of conjugated 3D cobalt oxide nanobeadÀCNTÀgraphene nanostructure for supercapacitor electrode has been reported in Ref. [16]

Summary

Introduction

Supercapacitors with high power density and storage capacity are devices for electrical energy storage. A solid-state paper based CNTs supercapacitor with H3PO4/PVA electrolyte has been studied by Rajmani et al [5]. They have shown the specific capacitance was 115 FgÀ1. Kumar et al [15] investigated the high-performance supercapacitor based on the Fe3O4/reduced graphene oxide nanosheets hybrid electrode. They showed the specific capacitances of 3D hybrid materials was 455 F gÀ1 at the scan rate of 8 mV sÀ1. That paper indicated for the 3D cobalt oxide nanobeadÀCNTÀgraphene electrode the specific capacitance of the supercapacitor was 600 FgÀ1 at the charge/discharge current density of 0.7AgÀ1

Methods

Results

Conclusion