High Performance Supercapacitor Based on Laser Induced Graphene for Wearable Devices

Mohamed R R Abdul-Aziz,Rami Ghannam,Ahmed S G Khalil,Ahmed A R Abdel-Aty,Hadi Heidari,A Hassan,Mohamed R Saber,Badawi Anis

doi:10.1109/access.2020.3035828

Abstract

To ensure maximum comfort for the wearer, electronic components that include energy harvesters need to be mechanically conformable. In this context, we demonstrate a versatile, cost-effective and efficient method for fabricating graphene supercapacitor electrodes using Laser Induced Graphene (LIG). A CO 2 laser beam instantly transforms the irradiated polyethersulfone polymer (PES) into a highly porous carbon structure. The LIG method was used to deposit graphene layers on graphite sheets to produce the supercapacitor electrodes. Graphene formation and morphology were examined and confirmed using several techniques including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) spectroscopy, Raman Spectroscopy and Fourier transform infrared spectroscopy (FTIR). Moreover, the electrochemical characterization was performed in different electrolytes (NaOH and KOH). At 5 mV s -1 , the LIG electrode achieved 165 mF cm -2 and 250 mF cm -2 in NaOH and KOH electrolytes, respectively. Consequently, we show that a wearable symmetric supercapacitor device with LIG electrodes achieved 98.5 mF cm -2 at 5 mV s -1 in KOH electrolyte. The device demonstrated an energy density of 11.3 μWh.cm -2 with power density of 0.33 mWcm -2 at 0.5 mA cm -2 . The retention of capacitance was 75% after 2000 cycles, with outstanding performance for the comparable graphene-based electrodes. These results further validate the use of LIG for developing flexible energy harvesters for wearable applications.

Highlights

The demand for novel energy storage devices has encouraged the development of novel materials for fabricating high-performance supercapacitors [1]
We show that a wearable symmetric supercapacitor device with Laser Induced Graphene (LIG) electrodes achieved 98.5 mF cm-2 at 5 mV s-1 in KOH electrolyte
LIG electrodes fabricated from polymeric structures demonstrated lower capacitance due to limited specific surface area compared with other carbon21 based materials, such as reduced graphene oxide [13]

Summary

INTRODUCTION

The demand for novel energy storage devices has encouraged the development of novel materials for fabricating high-performance supercapacitors [1]. LIG structures consist of a few layers of graphene with three-dimensional configuration, leading to advantages such as ultrahigh surface area, excellent conductivity, and high porosity. LIG electrodes fabricated from polymeric structures demonstrated lower capacitance due to limited specific surface area compared with other carbon based materials, such as reduced graphene oxide [13]. Increasing the porosity of electrodes is expected to enhance the electrolyte accessibility, improving the capacitance as well as its corresponding power densities [13]. The electrochemical supercapacitors electrode and device achieved a high capacitance and excellent stability in comparison to previously fabricated graphene-based supercapacitors. Polymer concentration during the phase separation process, allowing for the construction of a dense skin layer [40] This porosity is expected to enhance the capacitance performance.

Results and discussion

Electrochemical performance of the symmetric device

CONCLUSIONS