| Autor: |
Liang, Xueying, Mao, Zhifei, Shi, Xiaojun, Zhang, Taoqiu, Zheng, Zhi, Jin, Jun, He, Beibei, Wang, Rui, Gong, Yansheng, Wang, Huanwen |
| Zdroj: |
Journal of Materials Chemistry A; 9/14/2023, Vol. 11 Issue 34, p18097-18105, 9p |
| Abstrakt: |
Sodium-ion capacitors (SICs) have been designed to combine the advantages of high-energy batteries and high-power capacitors as well as low-cost sodium resources. However, anode materials usually exhibit sluggish diffusion of Na+, which results in kinetics imbalance with the capacitive cathode. Herein, the zeolitic imidazolate framework-8 (ZIF-8) layer is uniformly grown on the graphite surface (ZIF-8@Gr) to promote solvated-Na+ co-intercalation reactions in an ether electrolyte. The ZIF-8 coating can act as a multifunctional protection layer to inhibit electrolyte decomposition in the initial cycle, and also withstand volume expansion of graphite during the long-term co-intercalation process. The initial coulombic efficiency (ICE) of the ZIF-8@Gr electrode can be improved to 86%, much higher than that of the pristine graphite electrode (58%). More importantly, the ZIF-8@Gr electrode possesses ultrafast-charging sodium storage (20 A g−1, a full charge time within 16.2 s) and ultralong cycle life (96% and 94% capacity retention after 15 000 and 20 000 cycles at 5 A g−1 and 10 A g−1, respectively). By coupling the ZIF-8@Gr electrode with the activated carbon (AC) as the positive electrode, the as-fabricated SIC device demonstrates impressive energy//power densities (82 W h kg−1 at 518 W kg−1, 47 W h kg−1 at 10 370 W kg−1). These results indicate that ZIF-based surface modification enables graphite as a fast-charging and long-term cycling sodium-storage material. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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