Kariper, Ishak AfsinKorkmaz, SatiyeKaraman, CerenKaraman, Onur2024-09-292024-09-2920220016-23611873-7153https://doi.org/10.1016/j.fuel.2022.124497https://hdl.handle.net/20.500.14619/4684Herein, carbon nanotubes (CNTs) were oxygen functionalized by irradiation with diverse radiation sources including Am-241, Sr-90, Co-60, and Na-22 for the first time to be used as the electrode material in a high-energy supercapacitor. The oxygen contents of the irradiated CNTs were fine-tuned via the energy of the radiation source. The physicochemical characterization of as-obtained CNTs was conducted by X-Ray Diffraction (XRD), Raman, and Scanning Electron Microscopy, Energy Dispersive X-Ray (SEM-EDX) analysis whereas cyclic voltammetry and galvanostatic charge-discharge techniques were performed to assess the electrochemical performance of the as-assembled symmetrical supercapacitor cells. The CNT irradiated by Am-241 radiation source offered superior specific capacitance values compared to the other irradiated CNTs thanks to its higher content of oxygen functional groups. The highest specific capacitance for CNT Am-241 sample (with 7.32% oxygen) was calculated to be 489.6 F.g(-1) at a current density of 0.1 A.g(-1), which was almost 2.75 fold that of non-irradiated CNT sample. The capacitance retention of as-synthesized CNT Am-241 was determined as 98.50% for the 5,000th CV cycle. The outstanding energy density of 56.90 W.h.kg(-1) was achieved even at a high power density value of 9992.19 W.kg(-1), comparable to the commercial batteries, will pave the way for facile fabrication of high-energy electrochemical energy storage systems based on functionalized carbon nanotubes.eninfo:eu-repo/semantics/closedAccessCarbon nanotubesRadiation sourcesOxygen functionalizationHeteroatom dopingSupercapacitorsArticle10.1016/j.fuel.2022.1244972-s2.0-85129519662Q1324WOS:000799158900005Q1