Fabrication of Laser-Induced 3D Porous Graphene Electrodes for High-Performance Textile Microsupercapacitors

Abstract

In recent decades, form factor of electronic devices is continuously evolving from flat device to curved and foldable devices to rollable devices. Electronic textile (E-textile) or electronic skin (E-skin) is attracting a lot of attention as one of the ultimate form factor devices. Many researchers have tried to change the form factor as E-textiles or E-skin for lots of electronics such as sensors, actuators, energy harvesting applications, displays, and even energy storage devices. Unlike devices such as displays and sensors that have practical applications, reliable energy storage devices in the form as E-textile and E-skin have not yet been for practical applications. Microsupercapacitors (MSCs) has received a lot of attention as power sources for wearable, textile or stretchable electronic devices due to their fast charging capability, long life cycle, and good safety. Most of electrode patterns for textile MSCs have been fabricated using inking based printing techniques such as screen printing, inkjet printing, and 3D printing. Although the ink printing techniques are considered to be compatible with large-scale production, the preparation of inks based on high performance namaterials requires a costly, time-consuming and complicated process including high temperature synthesis or dispersion in an toxic organic solvent. A robust textile MSC fabrication process with low cost, large-area, and high-performance is thus requiredLaser-induced graphene (LIG), acquired by the direct laser synthesis of various types of carbon precursors, have widely investigated as electrode materials of MSCs with the advantages of 3D porous electrodes with hierarchical porosity, high crystallinity, and high surface area. However, these superior properties of LIG electrode were not adopted in textile energy storage devices yet.In this work, LIG-based MSCs were fabricated by thermal transfer printing on textile. A LIG electrode directly laser-written on a PI film was transferred onto the adhesive film area of textile substrates during thermal transfer printing. The electrochemical performances of the as-fabricated textile LIG-MSCs were investigated. Especially, LIG-MSCs based on LIG-metal composite electrodes exhibit fast ion transport for high-rate performance with capacitive rectangular shapes at high scan rates of up to 20V/s, suggesting outstanding rate capability among graphene-based textile MSCs. Moreover, LIG-MSCs demonstrated the possibility of practical usage as textile energy storage devices such as cyclic stability, a waterproof property, and control of the working voltage or capacitance by series or parallel connection.