Dyah Purwaningsih, A.K. Prodjosantoso, Siti Marwati, Dhaifina Vennyka Setiarini
This study investigates the impact of solvents (methanol, ethanol, 2-propanol, ethylene glycol, and polyethylene glycol) on the synthesis of MnO2/C composites derived from activated carbon from corn cobs, focusing on crystalline structure, surface area, and morphology. Additionally, it evaluates the specific capacitance of MnO2/C composites for supercapacitor applications. MnO2/C was synthesized via a solvothermal method, with solvent selection being key to optimizing capacitance. The process involved two stages: activated carbon preparation and solvothermal treatment. Various characterization techniques (SEM, TEM, SAA, XRD) and capacitance testing were employed to assess the properties and performance of the composites. The study found that MnO2/C synthesized with ethanol as the solvent achieved the highest specific capacitance of 47 mF/g, outperforming other solvents. X-ray diffraction (XRD) analysis revealed MnO₂ crystals with a crystallinity size of 20.55 nm in the α-MnO₂phase, making the composite highly suitable for supercapacitors. Surface area analysis (SAA) showed the highest surface area for the ethanol-based composite (239.608 m2/g), followed by ethylene glycol (238.816 m2/g), and methanol (196.62 m2/g). SEM-EDX confirmed the good deposition of MnO onto the carbon, with 54.66% MnO and 40.90% carbon. TEM revealed a polycrystalline structure in ethanol-derived MnO2/C, enhancing surface area. These results highlight how ethanol’s solubility, polarity, and molecular dimensions optimize the solvothermal process, leading to uniformly distributed MnO2 deposition. © 2025, Rasayan Journal of Chemistry, c/o Dr. Pratima Sharma. All rights reserved.
Department of Chemistry Education, Universitas Negeri Yogyakarta, 55281, Indonesia
