High performance flexible supercapacitors based on secondary doped PEDOT-PSS-graphene nanocomposite films for large area solid state devices

Syed Khasim; Apsar Pasha; Nacer Badi; Mohana Lakshmi; Yogendra Kumar Mishra

doi:10.1039/d0ra01116a

High performance flexible supercapacitors based on secondary doped PEDOT-PSS-graphene nanocomposite films for large area solid state devices

RSC Adv. 2020 Mar 12;10(18):10526-10539. doi: 10.1039/d0ra01116a. eCollection 2020 Mar 11.

Authors

Syed Khasim^{1

2

3}, Apsar Pasha⁴, Nacer Badi^{1

2}, Mohana Lakshmi³, Yogendra Kumar Mishra⁵

Affiliations

¹ Department of Physics, Faculty of Science, University of Tabuk Tabuk 71491 Kingdom of Saudi Arabia syed.pes@gmail.com.
² Renewable Energy Laboratory, Nanotechnology Research Unit, Faculty of Science, University of Tabuk Tabuk 71491 Kingdom of Saudi Arabia.
³ Department of Physics, PES University Bangalore-560100 Karnataka India.
⁴ Department of Physics, Gousia College of Engineering Ramanagaram 562159 Karnataka India.
⁵ Mads Clausen Institute, Nano SYD, University of Southern Denmark Alsion 2 6400 Sønderborg Denmark.

Abstract

In this work, we propose the development of high performance and flexible supercapacitors using reduced graphene oxide (rGO) incorporated poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT-PSS) nanocomposites by secondary doping. The structural and morphological features of the composite film were analyzed in detail using SEM, AFM, FTIR, XPS and TGA. Secondary doping of ethylene glycol (EG) assisted by rGO incorporation significantly enhances the room temperature conductivity of PEDOT-PSS films from 3 S cm^-1 to nearly 1225 S cm^-1 for a 10 wt% composite. The secondary doped PEDOT-PSS:EG/rGO composite film demonstrated improved electrochemical performances with specific capacitance of 174 (F g^-1) and energy density of 810 (W h kg^-1) which is nearly 4 times greater than pristine PEDOT-PSS due to synergetic interactions between rGO and PEDOT-PSS. The prepared composite films show long term stability with capacitance retention of over 90% after 5000 cycles of charging-discharging. The nanocomposite films used in the present investigation demonstrates percolative behavior with a percolation threshold at 10 wt% of rGO in PEDOT-PSS. The assembled supercapacitor device could be bent and rolled-up without a decrease in electrochemical performance indicating the potential to be used in practical applications. To demonstrate the practical applicability, a rolled-up supercapacitor device was constructed that demonstrates operation of a red LED for 40 seconds when fully charged. This study will provide new dimensions towards designing cost effective, flexible and all solid-state supercapacitors with improved electrochemical performance using electrodes based on secondary doped PEDOT-PSS/rGO organic thin films.