Boosting Transport Kinetics of Cobalt Sulfides Yolk–Shell Spheres by Anion Doping for Advanced Lithium and Sodium Storage
作者:Bo Wang、Yafei Cheng、Hao Su、Min Cheng、Yan Li、Hongbo Geng、Zhengfei Dai
DOI:10.1002/cssc.202001261
日期:2020.8.21
sulfides have been popularly used in energy storage because of their high theoretical capacity and abundant redox reactions. However, poor reaction kinetics, rapid capacity decay, and severe polarization owing to volume changes during electrochemical reaction are still huge challenges for cobalt sulfides in practical applications. Herein, cobalt sulfide yolk–shell spheres were synthesized by phosphorus
硫化钴因其高理论容量和丰富的氧化还原反应而广泛用于能量存储。然而,在实际应用中,对于硫化钴来说,不良的反应动力学,快速的容量衰减以及由于电化学反应期间的体积变化导致的严重极化仍然是巨大的挑战。在此,通过磷掺杂(P-CoS)合成了硫化钴卵黄壳球,以稳定硫化钴的结构并提高其电子/离子电导率。动力学测试和密度泛函理论计算证实,将磷引入硫化钴中大大降低了Li +在本征结构中的扩散势垒,从而改善了Li +期间电极材料的反应动力学。插入/提取过程。其结果是,P-CoS的电极提供高的锂存储容量(781毫安克-1 0.2 A G 100次循环后-1),优良的速率能力(489毫安克-1以10 A G -1),和出色的循环稳定性(在5 A g -1的4000个循环中没有明显的容量衰减)。特别是对于钠离子电池应用,在900次循环后,P-CoS电极在2 A g -1时的打击容量约为260 mAh g -1。