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In this study, we synthesized carbyne by a simple chemical route and then this was coated on nickel foam. On this carbyne coated nickel foam, FeCo2O4 was grown by the solvothermal process to serve as a nanohybrid electrode for supercapacitor applications. This nanohybrid electrode has shown high specific capacitance due to the large surface area, high electrical conductivity and improved rate characteristics. The specific capacitance of FeCo2O4 @ Carbyne nanohybrid electrode was about 2584.8 Fg-1 at the current density of 3 Ag-1. Furthermore, the asymmetric supercapacitor device integrated with FeCo2O4 @ Carbyne and activated carbon (FeCo2O4 @ Carbyne || AC) shows better performance with an energy density of about 96.59 WhKg-1 at a high-power density of 2.25 kW kg-1 with a capacitance decay of about 14.52 % even at 5000 cycles. These outcomes provide a new approach for the development of supercapacitors with superior characteristics.
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Germanium‐Functionalized 3D Microporous, Nanostructured Nickel–Nickel Oxides for Application in Asymmetric Supercapacitors
Supercapacitors and batteries are essential for sustainable energy development. However, the bottleneck is the associated high cost, which limits bulk use of batteries and supercapacitors. In this context, realizing that the cost of energy‐storage device mainly depends on materials, synthesis processes/procedures, and device fabrication, an effort is made to rationally design and develop novel low‐cost electrode materials with enhanced electrochemical performance in asymmetric supercapacitors. Herein, surface functionalization approach is adopted to design low‐cost 3D mesoporous and nanostructured nickel–nickel oxide electrode materials using facile synthesis for application in supercapacitors. It is demonstrated that the 3D mesoporous Ni provides the high surface area and enhanced ionic conductivity, while germanium functionalization improves the electrical conductivity and reduces the charge‐transfer resistance of NiO. Surface functionalization with Ge demonstrates the significant improvement in specific capacitance of NiO. The asymmetric supercapacitor using these Ge‐functionalized NiO–Ni electrodes provides a specific capacitance of 304 Fg−1(94 mF cm−2), energy density of 23.8 Wh kg−1(7.35 μWh cm−2), and power density of 6.8 kW kg−1(2.1 mW cm−2) with excellent cyclic stability of 92% after 10 000 cycles. To validate their practical applications, powering the digital watch using the asymmetric supercapacitors in laboratory conditions is demonstrated.
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- Award ID(s):
- 1827745
- PAR ID:
- 10523540
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Energy Technology
- Volume:
- 11
- Issue:
- 10
- ISSN:
- 2194-4288
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/ente.202300360
