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The growth of metal oxides on a conductive substrate, which forms some metal\/oxide structure, has been demonstrated to be an efficient method for increasing the charge transfer efficiency. Through the control and variation of synthetic parameters, different structures and morphologies of iron oxide were obtained, including hexagonal structures with a hollow ball shape and rhombohedral structures with rhombus-like shapes. Structural and morphological characterization methods such as X-ray diffraction and SEM morphology were used on the as-synthesized composite materials. The supercapacitor properties of the as-developed amorphous ribbons decorated with Fe2O3 nanoparticles were investigated by cyclic voltammetry, galvanostatic charge discharge, and electrochemical impedance spectroscopy. The flexible supercapacitor negative electrode demonstrates a specific capacitance of 5.96 F g\u22121 for the 0.2 M NaOH treated sample and 8.94 Fg\u22121 for the 0.4 M NaOH treated sample. The 0.2 M treated negative electrodes deliver 0.48 Wh\/kg at a power density of 20.11 W\/kg, and the 0.4 M treated electrode delivers 0.61 Wh\/kg at a power density of 20.85 W\/kg. The above results show that these flexible electrodes are adequate for integration in supercapacitor devices, for example, as negative electrodes.<\/jats:p>","DOI":"10.3390\/ma16072820","type":"journal-article","created":{"date-parts":[[2023,4,3]],"date-time":"2023-04-03T02:10:13Z","timestamp":1680487813000},"page":"2820","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Fabrication of Flexible Supercapacitor Electrode Materials by Chemical Oxidation of Iron-Based Amorphous Ribbons"],"prefix":"10.3390","volume":"16","author":[{"given":"Mircea","family":"Nicolaescu","sequence":"first","affiliation":[{"name":"Department of Materials and Manufacturing Engineering, Faculty of Mechanical Engineering, Politehnica University Timisoara, Mihai Viteazu 1, 300222 Timisoara, Romania"},{"name":"National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melinda","family":"Vajda","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania"},{"name":"Department of Applied Chemistry and Engineering of Inorganic Compounds and Environment, Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Piata Victoriei 2, 300006 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carmen","family":"Lazau","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Corina","family":"Orha","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6133-5574","authenticated-orcid":false,"given":"Cornelia","family":"Bandas","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development in Electrochemistry and Condensed Matter, Dr. A. P. Podeanu 144, 300569 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Viorel-Aurel","family":"Serban","sequence":"additional","affiliation":[{"name":"Department of Materials and Manufacturing Engineering, Faculty of Mechanical Engineering, Politehnica University Timisoara, Mihai Viteazu 1, 300222 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cosmin","family":"Codrean","sequence":"additional","affiliation":[{"name":"Department of Materials and Manufacturing Engineering, Faculty of Mechanical Engineering, Politehnica University Timisoara, Mihai Viteazu 1, 300222 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Yaseen, M., Khattak, M.A.K., Humayun, M., Usman, M., Shah, S.S., Bibi, S., Hasnain, B.S.U., Ahmad, S.M., Khan, A., and Shah, N. (2021). 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