Institute for Superconducting & Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong , Innovation Campus, Squires Way, North Wollongong, New South Wales 2500, Australia.
Department of Chemical Engineering, Monash University , Clayton, Victoria 3800, Australia.
J Am Chem Soc. 2016 Dec 28;138(51):16576-16579. doi: 10.1021/jacs.6b08685. Epub 2016 Dec 19.
Despite the high theoretical capacity of the sodium-sulfur battery, its application is seriously restrained by the challenges due to its low sulfur electroactivity and accelerated shuttle effect, which lead to low accessible capacity and fast decay. Herein, an elaborate carbon framework, interconnected mesoporous hollow carbon nanospheres, is reported as an effective sulfur host to achieve excellent electrochemical performance. Based on in situ synchrotron X-ray diffraction, the mechanism of the room temperature Na/S battery is proposed to be reversible reactions between S and NaS, corresponding to a theoretical capacity of 418 mAh g. The cell is capable of achieving high capacity retention of ∼88.8% over 200 cycles, and superior rate capability with reversible capacity of ∼390 and 127 mAh g at 0.1 and 5 A g, respectively.
尽管钠离子电池具有很高的理论容量，但由于其硫的电化学活性低和穿梭效应加剧，其应用受到严重限制，导致可用容量低，衰减快。在此，报道了一种精心设计的碳骨架，即相互连接的介孔中空碳纳米球，作为一种有效的硫主体，以实现优异的电化学性能。基于同步辐射 X 射线衍射，提出了室温 Na/S 电池的反应机理，即 S 和 NaS 之间的可逆反应，对应于 418 mAh g 的理论容量。该电池能够在 200 次循环中保持约 88.8%的高容量保持率，并且具有优异的倍率性能，在 0.1 和 5 A g 时的可逆容量分别约为 390 和 127 mAh g。
