Endah Rianingsih, Muhammad Yuliantito Budiono, Khakam Ma'ruf, Rizal Justian Setiawan, Darmono
The development of efficient and sustainable energy storage systems remains a major technological challenge in addressing the global energy crisis. Among various energy storage devices, supercapacitors have attracted significant attention due to their long lifespan, rapid charging capability, and high operational safety. This study investigates the influence of ultrasonication and hydrothermal treatment durations on the physicochemical and electrochemical properties of graphene. Graphene was synthesized from graphite using a modified Hummers method, followed by chemical reduction with zinc (Zn) metal and subsequent hydrothermal treatment. Graphite oxide was prepared using NaNO3, concentrated H2SO4, and KMnO4, initially reacted below 20°C for 2 hours, then maintained at 35°C for 24 hours. The resulting graphite oxide underwent ultrasonication for 2, 4, and 6 hours to form graphene oxide (GO), followed by Zn-assisted reduction under acidic conditions. The reduced GO was then treated hydrothermally at 200°C for 6, 9, and 12 hours. Characterization included X-Ray Diffraction (XRD) for structural analysis, Cyclic Voltammetry (CV) for capacitance evaluation, and the Two-Probe method for electrical conductivity measurement. Variations in ultrasonication and hydrothermal durations significantly influenced d-spacing, crystallite size, number of graphene layers, specific capacitance, and conductivity. The optimal condition was obtained with 4 hours of ultrasonication and 12 hours of hydrothermal treatment, producing a d-spacing of 3.67 \AA, crystallite size of 1.49 nm, 4.06 graphene layers, capacitance of 191.18 F\g, and conductivity of 29.2072 S/m. These results highlight the potential of optimized graphene synthesis for fabricating high-performance, cost-effective supercapacitor electrode materials. © 2025 IEEE.
Universitas Negeri Yogyakarta, Faculty of Mathematics and Natural Sciences, Dept of Chemistry Education, Yogyakarta, Indonesia; Universitas Gadjah Mada, Faculty of Engineering, Dept of Industrial Engineering, Yogyakarta, Indonesia; College of Engineering, Yuan Ze University, Dept of Industrial Engineering and Management, Taoyuan, Taiwan; Universitas Negeri Yogyakarta, Faculty of Engineering, Dept of Civil Engineering Education, Yogyakarta, Indonesia
