Li Xu, Han Xinpeng, Liu Runze, Zhang Shaojie, Zhang Yiming, Cao Yu, Wang Xiaoyi, Wang Ruying, Yang Zhanxu, Sun Jie
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Tianjin Coslight Automotive Technology Co., Ltd., Tianjin 301709, China.
Nanoscale. 2022 Mar 7;14(9):3625-3631. doi: 10.1039/d1nr07987e.
Phosphorus has been considered a promising anode material for lithium-ion batteries because of its high specific capacity of 2596 mA h g and safe lithiation voltage of 0.7 V. However, the practical application of the phosphorus anode is challenged by its poor cyclability associated with the dissolution of phosphorus intermediates, the enormous volume expansion and the sluggish lithiation reaction kinetics during the cycling process. Herein, a multifunctional coating layer is designed and fabricated on the surface of a phosphorus-carbon nanotube (P-CNT) electrode the facile polymerization of plant-derived tannic acid (TA) and pyrrole (Py). This coating layer shows strong adsorption of phosphorus and its derivatives, buffers the volumetric expansion of phosphorus and facilitates efficient Li-ion transport, thus enhancing phosphorus utilization during the cycling process. As a result, the P-CNT@TA-PPy hybrid exhibits a stable coulombic efficiency of 99.0% at 520 mA g after 100 cycles and a reduced volumetric expansion of 50% at 260 mA g, superior to P-CNT with its unstable coulombic efficiency and large electrode expansion of 329%. This study sheds light on the rational design of advanced phosphorus-based anodes for alkali metal-ion batteries.
由于磷具有2596 mA h g的高比容量和0.7 V的安全锂化电压，它一直被认为是一种很有前景的锂离子电池负极材料。然而，磷负极的实际应用面临挑战，因为在循环过程中，磷中间体的溶解、巨大的体积膨胀以及缓慢的锂化反应动力学导致其循环性能较差。在此，通过植物源单宁酸（TA）和吡咯（Py）的简便聚合，在磷-碳纳米管（P-CNT）电极表面设计并制备了一种多功能涂层。该涂层对磷及其衍生物具有很强的吸附作用，缓冲了磷的体积膨胀，并促进了锂离子的高效传输，从而提高了循环过程中磷的利用率。结果，P-CNT@TA-PPy复合材料在520 mA g下循环100次后表现出99.0%的稳定库仑效率，在260 mA g下体积膨胀降低了50%，优于P-CNT，后者的库仑效率不稳定，电极膨胀高达329%。这项研究为碱金属离子电池先进磷基负极的合理设计提供了思路。
