A high‐energy aqueous sodium‐ion capacitor with nickel hexacyanoferrate and graphene electrodes
- Journal
- ChemElectroChem
- Page
- 3302-3308
- Year
- 2017
- Link
- https://doi.org/10.1002/celc.201700690 205회 연결
Abstract
Sodium-ion capacitors have received much attention compared to lithium-based systems, owing to the improved safety and earth abundancy. Here, we assembled an aqueous sodium-ion capacitor by using nickel hexacyanoferrate and graphene as positive and negative electrodes, respectively, in 1 M Na2SO4 electrolyte. The fabricated capacitor can work in a wide potential window from 0 to 2 V, giving an energy density of 39.35 Wh kg−1 with better capacitance retention of about 91 %, even after 2000 cycles. Besides, the cost-effective precursors as well as environmentally friendly and earth-abundant electrolytes with high safety will ensure that the fabricated sodium-ion capacitor system is suitable for next-generation energy storage applications.