Pyrolytic Jetting of Free-Standing Laser-Induced Graphene Fiber for Cost-Effective Supercapacitor

In recent times, the significance of energy storage has surged due to the expanding use of renewable energy for achieving carbon neutrality. Efficient energy storage is crucial for stabilizing power grids amid the intermittent energy production from sources like solar and wind, as well as for meeting the escalating demand for reliable energy storage. Simultaneously, the rapid and widespread adoption of electric vehicles has highlighted the significance of energy storage solutions. As conventional combustion engines give way to electric-powered vehicles, an escalating demand emerges for energy storage systems that embody safety, reliability, and cost-efficiency while delivering requisite power. These advancements underscore the growing significance of energy storage in shaping our energy landscape and ensuring future energy security. As our society steadily progresses towards a sustainable, low-carbon trajectory, the need for versatile energy storage solutions is accentuated.<br/><br/>Supercapacitors offer distinct advantages, including higher power density, extended cycle life, and simpler material composition compared to batteries, making them a prominent energy storage solution. Graphene, particularly in the form of Laser-Induced Graphene (LIG), has emerged as a standout material for supercapacitors due to its rapid charging/discharging capabilities and extensive specific surface area. LIG's unique porous morphology holds great promise for various applications and has the potential to enhance energy storage performance by maximizing surface-area-to-volume ratios. Considering an environmentally conscious perspective, it becomes imperative to minimize energy consumption and material utilization during the fabrication process, while simultaneously maximizing storage capacity. A recent study in laser technology, known as pyrolytic jetting, has come to light under precise laser conditions (125 J/m). This innovation yields an incredibly porous, freestanding fiber-shaped LIG, demonstrating potential advantages for energy storage applications. In contrast to electrodes affixed to specific substrates, these fiber-shaped electrodes present significant merits as energy devices for diverse applications, notably through their remarkable characteristic. Despite its vast potential, research on its practical application in energy devices has been relatively limited.<br/><br/>Our study on laser pyrolytic jetting presents an efficient method to produce highly porous, free-standing graphene fibers from polyimide film. This process involves precise scanning of a continuous-wave laser, resulting in significant advantages over conventional LIG techniques. In this follow-up investigation, we demonstrate the superior potential of the laser pyrolytic jetting process for energy device applications, offering remarkable energy and material savings. Notably, the pyrolytic jetting process significantly increases the volume of the pyrolyzed product compared to conventional LIG, leading to an expanded surface area capable of storing a greater amount of electric charges. Raman measurement verifies the comparable attributes of the exfoliated material obtained through pyrolytic jetting and traditional LIG, making it exceptionally suitable for supercapacitor applications. Consequently, supercapacitors produced via pyrolytic jetting demonstrate a notable increase in capacitance, indicating an improvement of over 4.7 times compared to conventional LIG. This underscores the potential of pyrolytic jetting as a cost-effective fabrication technique for carbon-based energy devices.