Green Synthesized Carbon Quantum Dots/Cobalt Sulfide Nanocomposite as Efficient Electrode Material for Supercapacitors

• Published in: Energy & fuels 2021-06, Vol.35 (11), p.9635-9645
• Main Authors: Arsalani, Nasser, Ghadimi, Laleh Saleh, Ahadzadeh, Iraj, Tabrizi, Amin Goljanian, Nann, Thomas
• Format: Article
• Language: English
• Subjects: Batteries and Energy Storage
• ISSN: 0887-0624; 1520-5029
• DOI: 10.1021/acs.energyfuels.1c00369

In the present work, carbon quantum dots/CoS2 nanocomposite (CQDs/CoS2) was prepared through a solvent-free ball milling route followed by solvothermal treatment. The CQDs were prepared first by a green catalyst-free microwave-assisted procedure from glycerol, as a single precursor, with a quantum yield of ∼16%. Then, a ball mill–hydrothermal combination method was used to synthesize CQDs/CoS2 with edged bricklike morphology. Benefiting from advantageous features of large specific surface area (427.2 m2 g–1), unique nanostructure with high mesoporosity, and greater electronic conductivity, the as-synthesized CQDs/CoS2 nanocomposite electrode material displays a rather high specific pseudocapacitance, about 808 F g–1 at 1 A g–1 current density, a high rate capability with 83.9% capacity retention rate at 20 A g–1, and good cycling stability of 98.75% over 10 000 charge/discharge cycles at 1 A g–1. The attained results support the suitability of CQDs/CoS2 nanocomposite as a desired material for future high-performance electrochemical energy storage devices.