Abstract
We demonstrate a facile and controllable synthesis of horn-like Co3O4 nanostructures through a solvothermal process followed by calcination at different temperatures. The particle sizes and defects of the as-obtained Co3O4 nanohorns are controlled with respect to calcining temperatures, while preserving the horn-like morphology. In particular, the Co3O4 nanohorn electrodes prepared at 300 °C reveal the specific capacitance of ∼2751 F g−1 and the rate capability of 46.8%, which is greater than those of materials obtained at 350, 400, and 450 °C. In order to enlarge the potential window, a hybrid supercapacitor is configured with the Co3O4 nanohorn and activated carbon used as positive and negative electrodes, respectively. The as-fabricated hybrid supercapacitor shows high specific capacitance of ∼101 F g−1 and the rate capability of 80.5%. The energy and power densities of hybrid supercapacitor are ∼31.70 W h kg−1 and 16.71 kW kg−1, respectively, along with 91.37% of capacitance retention over 350,000 cycles. These energy and power densities of the hybrid supercapacitors are approximately 8.5 and 3.5 times greater than values of Co3O4 symmetric supercapacitor.
Original language | English |
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Pages (from-to) | 147-156 |
Number of pages | 10 |
Journal | Journal of Power Sources |
Volume | 402 |
DOIs | |
State | Published - 31 Oct 2018 |
Bibliographical note
Funding Information:This work was supported by the Energy Efficiency & Resources program of the Korea Institute of Energy Technology Evaluation and Planning , and was granted financial resources from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20152020105770 ), the Korea Electric Power Corporation (Grant number: R17XA05-52 ), and the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education ( NRF-2017R1D1A1B03036362 ).
Publisher Copyright:
© 2018 Elsevier B.V.
Keywords
- Cobalt oxide
- Electrode materials
- High energy
- Hybrid device
- Nanoarchitecture
- Supercapacitor