Titanium carbide/reduced graphene oxide (Ti 3 C 2 T z /rGO) gels were prepared by a one-step hydrothermal process. The gels show a highly porous structure with a surface area of ∼224 m 2 g −1 and average pore diameter of ∼3.6 nm. The content of GO and Ti 3 C 2 T z nanosheets in the reaction precursor was varied to yield different microstructures. The supercapacitor performance of Ti 3 C 2 T z /rGO gels varied significantly with composition. Specific capacitance initially increased with increasing Ti 3 C 2 T z content, but at high Ti 3 C 2 T z content gels cannot be formed. Also, the retention of capacitance decreased with increasing Ti 3 C 2 T z content. Ti 3 C 2 T z /rGO gel electrodes exhibit enhanced supercapacitor properties with high potential window (1.5 V) and large specific capacitance (920 F g −1 ) in comparison to pure rGO and Ti 3 C 2 T z . The synergistic effect of EDLC from rGO and redox capacitance from Ti 3 C 2 T z was the reason for the enhanced supercapacitor performance. A symmetric two-electrode supercapacitor cell was constructed with Ti 3 C 2 T z /rGO, which showed very high areal capacitance (158 mF cm −2 ), large energy density (∼31.5 μW h cm −2 corresponding to a power density of ∼370 μW cm −2 ), and long stability (∼93% retention) after 10 000 cycles.
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In-situ grown of FeCo2O4 onto 2D-Carbyne coated nickel foam - A newer nanohybrid electrode for high performance supercapacitor
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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- Award ID(s):
- 2122147
- PAR ID:
- 10423981
- Date Published:
- Journal Name:
- Journal of energy storage
- Volume:
- 56
- ISSN:
- 2352-1538
- Page Range / eLocation ID:
- 105943
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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