Bintang Dwi Nur Rohmad, Andri Hardiansyah, Resetiana Dwi Desiati, Khusnul Khotimah, Angga Hermawan, Łukasz Pawłowski, Zubaidah Ningsih
The development of high-performance supercapacitor electrodes relies on materials that combine high electrical conductivity, large accessible surface area, and stable redox behavior. In this study, rGO/MnO2/Zeolitic Imidazolate Framework-8 (ZIF-8) composite electrodes were fabricated on nickel foam through a sequential electrophoretic deposition (EPD) technique. Graphene oxide was synthesized via the Tour method, MnO2 was obtained through a co-precipitation process followed by calcination, and ZIF-8 was subsequently deposited to construct a ternary hybrid structure. Raman spectroscopy confirmed the formation of β-MnO2 and rGO, with an increased ID/IG ratio (1.81), indicating higher defect density favorable for electrochemical activity. FESEM–EDX analysis revealed a hierarchical architecture composed of rGO nanosheets supporting MnO2 nanoparticles and ZIF-8 crystals with uniform elemental distribution, confirming successful composite integration. Electrochemical characterization in 0.5 M Na2SO4 demonstrated that rGO/MnO2/ZIF-8 electrode delivered the highest performance compared to pristine MnO2 (17.19 F g− 1) and ZIF-8 (11.83 F g− 1), exhibiting a specific capacitance of 42.90 F g− 1 at 10 mV s− 1 (CV) and 30.74 F g− 1 at 0.1 A g− 1 (GCD).The b-value analysis suggested a combined capacitive and diffusion-controlled mechanism, while EIS results indicated a markedly reduced charge-transfer resistance (Rct = 180.8 Ω), attributed to the conductive rGO network and the porous ZIF-8 framework. These synergistic effects enhanced electron transport, ion diffusion, and redox activity. Overall, the rGO/MnO2/ZIF-8 composite demonstrates improved electrochemical performance and structural stability, highlighting its potential as a promising electrode material for next-generation supercapacitors. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026.
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Brawijaya University, Malang, 65145, Indonesia; Research Center for Nanotechnology Systems, National Research and Innovation Agency (BRIN), Tangerang Selatan, 15314, Indonesia; Research Center for Energy Materials, National Research and Innovation Agency (BRIN), Tangerang Selatan, 15314, Indonesia; Department of Biomaterials Technology, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk, 80-233, Poland
