Flexible high specific capacitance supercapacitor based on Laser-Induced Graphene with an optimize design on interdigitated electrodes

Laser-induced graphene (LIG) has emerged as a prominent subject in materials science due to its streamlined fabrication and superior electrical conductivity. This study identifies the optimal laser parameters—specifically a power of 6 W and a scanning speed of 127 mm/s—for the synthesis of LIG interdigitated electrodes (IDEs). Following fabrication, a solid-state electrolyte composed of sulfuric acid (H2SO4), polyvinyl alcohol (PVA), and deionized water was applied to the optimize designed IDEs to construct the LIG supercapacitor. Electrochemical characterization via cyclic voltammetry (CV) revealed a high specific capacitance of 8.678 mF/cm², with 60.2% retention (5.225 mF/cm²) after a 60-day aging period. Furthermore, multistep potentiometry (MP) analysis yielded an energy density of 4.82 µWh/cm² and a power density of 0.289 mW/cm². These results demonstrate a rapid, cost-effective manufacturing route for LIG-based energy storage devices. The interdigitated architecture effectively maximizes the electrochemically active surface area, thereby enhancing capacitive performance without expanding the physical footprint or material consumption.