Synthesis of High-Performance Laser-Induced Graphene Microsupercapacitors from Polyimide Films

Abstract

Rapid advancements in the field of microelectronics coupled with the inefficiency of micro batteries has led to the growing need for new rechargeable micropower sources. Carbon-based micro-supercapacitors (MSCs) are miniaturized energy-storage devices that have proven to be promising due to their superior power density, fast charge/discharge rates, and long cycling life; however, the lack of cost-effective synthesis and patterning mechanisms of carbon nanomaterials into MSCs poses a major challenge for their production. Here, we present a one-step approach for producing graphene from polymer films using an infrared laser (LIG). The photothermal energy of the laser converts sp3 carbon atoms in polyimide films to the sp2 carbon atoms in graphene.
One measure of MSC performance is specific areal capacitance, which refers to the charge-storage ability of the device per unit area. In 1M H2SO4, the LIG-MSCs exhibited a specific areal capacitance of up to 0.48 mF/cm2 (determined by cyclic voltammetry), which is lower than other LIG-MSCs, but comparable to electrodeposited graphene-based MSCs. The performance of these devices may be improved by using polymers with different functional groups or nanostructures which could increase the specific surface area of LIG-MSC electrodes and may therefore increase the specific areal capacitance.