Electrochemically exfoliated graphene sheets as electrode material for aqueous symmetric supercapacitorsShow others and affiliations
2021 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 416, article id 127150Article in journal (Refereed) Published
Abstract [en]
In this work, we have demonstrated a prompt anodic electrochemical exfoliation of graphite into graphene sheets (GS) in aqueous media. For the synthesis of GS, a constant potential of +10 V has been applied between two identical graphite sheets in 0.1 M aqueous ammonium sulfate. The exfoliated GS were characterized via standard analytical tools such as Fourier transform infra red spectroscopy (FT-IR), X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy with energy dispersive spectrum (FE-SEM with EDS). Further, the electrochemical performance of GS coated Ni foam (GS/Ni foam) was assessed by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques in 2 M KOH. The quasi-rectangular shaped voltammograms and charge-discharge curves in a three-electrode system evidenced the double-layer capacitance of GS and GS/Ni foam which exhibited maximum specific capacitance of 84.8 and 40. 8 F/g at 2 mV/s, and 0.1 A/g of current density, respectively. Moreover, the symmetric two-electrode performance of GS/Ni foam was also examined, which showed good energy density (3.03 Wh/kg) and power density (562.5 W/kg). This study proves that the anodically exfoliated GS can act as a good symmetric supercapacitor in KOH.
Place, publisher, year, edition, pages
Elsevier, 2021. Vol. 416, article id 127150
Keywords [en]
Electrochemical exfoliation, Anodic exfoliation, Graphene sheets, Double-layer, Symmetric supercapacitors
National Category
Materials Chemistry
Research subject
Machine Elements
Identifiers
URN: urn:nbn:se:ltu:diva-83692DOI: 10.1016/j.surfcoat.2021.127150ISI: 000655573400007Scopus ID: 2-s2.0-85104600352OAI: oai:DiVA.org:ltu-83692DiVA, id: diva2:1544440
Note
Godkänd;2021;Nivå 0;2021-04-19 (alebob);
Finansiär: National Research Foundation (NRF) of Korea funded by the Ministry of Education, Science, and Technology (2012M3A7B4049677); Ministry of Science, Information and Communications Technology (MSIT) (2018R1A2B2004432)
2021-04-152021-04-152023-09-05Bibliographically approved