Fabrication of Ultrathin rGO Sheet-Wrapped Mixed-Phase MnSe2/CoSe2 Nanocomposite for High-Performance Supercapacitor Electrodes with Long-Term Stability

• Published in: Journal of electronic materials Vol. 53; no. 9; pp. 5273 - 5285
• Main Authors: Krishnan, T. Santhana, Babu, P. Sathish, Praveen, M., Janakiraman, V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-09-2024; Springer Nature B.V
• Subjects: Acetylene; Characterization and Evaluation of Materials; Chemical synthesis; Chemistry and Materials Science; Electrochemical analysis; Electrodes; Electronics and Microelectronics; Electrons; Energy storage; Graphene; Hybrid composites; Instrumentation; Materials Science; Metal foams; Metal sulfides; Nanocomposites; Optical and Electronic Materials; Original Research Article; Photoelectrons; Pore size distribution; Production methods; Redox reactions; Solid State Physics; Stability; Structural analysis; Supercapacitors; Transition metal compounds; X ray photoelectron spectroscopy; three electrode system; rGO; CoSe; MnSe; synergistic effect; supercapacitor
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-024-11257-9

Binary transition metal chalcogenides and reduced graphene oxide exhibit significant potential for energy storage devices due to their superior electronic conductivity and capacity, surpassing that of single-metal sulfides, owing to their more extensive redox reactions. In this report, we introduce a novel synthesis method for producing a mixed-phase MnSe
2
/CoSe
2
nanocomposite wrapped with reduced graphene oxide (rGO) sheets, designed specifically for supercapacitor applications. The MnSe
2
/CoSe
2
hybrid material was synthesized using an ultrasonic assisted hydrothermal technique, followed by the preparation of the rGO/MnSe
2
/CoSe
2
hybrid composite. The structural characterization was conducted employing x-ray diffraction (XRD), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and Raman techniques. Brunauer–Emmett–Teller (BET) analysis demonstrated a significant specific surface area (66.5 m
2
/g) and a pore size distribution of 28.4 nm in rGO-MnSe
2
/CoSe
2
. The interconnected ultrathin rGO nanosheets and conductive carbon layer contributed to the exceptional conductivity and stability achieved by the rGO/MnSe
2
/CoSe
2
composite electrode. The electrochemical performance was assessed using a three-electrode setup in a 3 M KOH solution, with nickel foam as the current collector. The working electrode, consisting of rGO/MnSe
2
/CoSe
2
, acetylene black and PVDF in an 80:15:5 weight ratio, demonstrated specific capacitance of 1214 F g
−1
and cycling stability of 88% retention after 5000 cycles at 1 A g
−1
. An asymmetric supercapacitor, constructed using a tailored electrode composition, achieved energy density of 28.6 Wh kg
−1
at 2100 W kg
−1
and high power density of 888 W kg
−1
at 49.7 Wh kg
−1
.
Graphical Abstract