Pimklang T.Watthanaphanit A.Hemnon W.Sodtipinta J.Panomsuwan G.Chantaramethakul J.Sriprachuabwong C.Poochai C.Tuantranont A.Pakawatpanurut P.Mahidol University2025-05-092025-05-092025-09-01Materials Chemistry and Physics Vol.341 (2025)02540584https://repository.li.mahidol.ac.th/handle/123456789/110017This study introduces a greener and scalable solution plasma process (SPP) for synthesizing reduced graphene oxide–manganese dioxide (rGO-MnO2) nanocomposites with precise phase control, offering a novel alternative to conventional hydrothermal processes (HTP). Unlike HTP, which typically produces mixed-phase manganese oxides, SPP enables the selective deposition of pure δ-MnO2 onto rGO surfaces using potassium permanganate (KMnO4) in an aqueous system. Additionally, rGO is prepared without toxic reductants, enhancing the sustainability of the process. Electrochemical evaluations reveal that SPP-derived rGO-MnO2 (SPP-rGOM) achieves a specific capacitance of 89.2 F g−1, comparable to HTP-rGOM (92.5 F g−1), while demonstrating significantly superior cycling stability—retaining 76.8 % of its capacitance after prolonged cycling compared to 54.0 % for HTP-rGOM at 30 mV s−1. These findings establish SPP as an innovative, environmentally friendly approach for the scalable production of durable, high-performance electrode materials for energy storage applications.Materials SciencePhysics and AstronomyArticleSCOPUS10.1016/j.matchemphys.2025.1309482-s2.0-105003698966