Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors

TLDR

Although electrochemical capacitors charge and discharge faster than batteries, they are still limited by low energy densities and slow rate capabilities. We used a standard LightScribe DVD optical drive to directly laser‑reduce graphite oxide films to graphene. The laser‑reduced graphene films exhibit high conductivity (1738 S m⁻¹), large surface area (1520 m² g⁻¹), and mechanical robustness, enabling binder‑free electrodes that deliver ultrahigh energy density, high power density, excellent cycle stability, and retain performance under high mechanical stress, making them suitable for high‑power flexible electronics.

Abstract

Although electrochemical capacitors (ECs), also known as supercapacitors or ultracapacitors, charge and discharge faster than batteries, they are still limited by low energy densities and slow rate capabilities. We used a standard LightScribe DVD optical drive to do the direct laser reduction of graphite oxide films to graphene. The produced films are mechanically robust, show high electrical conductivity (1738 siemens per meter) and specific surface area (1520 square meters per gram), and can thus be used directly as EC electrodes without the need for binders or current collectors, as is the case for conventional ECs. Devices made with these electrodes exhibit ultrahigh energy density values in different electrolytes while maintaining the high power density and excellent cycle stability of ECs. Moreover, these ECs maintain excellent electrochemical attributes under high mechanical stress and thus hold promise for high-power, flexible electronics.