Wang Qiufan, Qu Zaiting, Chen Shenghui, Zhang Daohong
Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, Hubei R&D Center of Hyperbranched Polymers Synthesis and Applications, South-Central Minzu University, Wuhan 430074, China.
Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, Hubei R&D Center of Hyperbranched Polymers Synthesis and Applications, South-Central Minzu University, Wuhan 430074, China.
J Colloid Interface Sci. 2022 Oct 15;624:385-393. doi: 10.1016/j.jcis.2022.03.053. Epub 2022 Mar 18.
Cobalt sulfide (CoS) is a promising battery-type material for electrochemical energy storage. However, the poor conductivity and slow charge transfer kinetics as well as the deficiency of electrochemically active sites seriously limit their applications. Herein, a class of the P-doping induced hexagonal CoS nanosheets with S defects (P-CoS) derived from Co-based metal organic frameworks (MOFs) supported on carbon nanotube film (CNT) is designed and prepared. The density functional theory (DFT) simulations show the higher conductivity of the P-CoS electrode than CoS. Taking advantage of the synergistic effects of the high conductive P-CoS nanosheets with rich S defects and the flexible CNT, the P-CoS/CNT electrode exhibits a high reversible capacity of 4.3F cm, remarkable rate capability, and outstanding long-term cyclability. Impressively, the flexible asymmetric supercapacitor (ASC) based on P-CoS//CoS@PPy achieves a satisfying energy density of 0.18 mWh cm and high bending stability. The electrocatalytic result suggests that the P-CoS possesses the lowest overpotential and the smallest Tafel slope. This vacancy engineering strategy also provides a new insight into active materials and should be beneficial for the design of the next generation of energy storage devices.
硫化钴（CoS）是一种很有前景的用于电化学储能的电池型材料。然而，其导电性差、电荷转移动力学缓慢以及电化学活性位点不足严重限制了它们的应用。在此，设计并制备了一类由负载在碳纳米管薄膜（CNT）上的钴基金属有机框架（MOF）衍生而来的具有硫缺陷的P掺杂诱导六方CoS纳米片（P-CoS）。密度泛函理论（DFT）模拟表明P-CoS电极的导电性高于CoS。利用具有丰富硫缺陷的高导电P-CoS纳米片与柔性CNT的协同效应，P-CoS/CNT电极展现出4.3F cm的高可逆容量、出色的倍率性能和优异的长期循环稳定性。令人印象深刻的是，基于P-CoS//CoS@PPy的柔性不对称超级电容器（ASC）实现了0.18 mWh cm的令人满意的能量密度和高弯曲稳定性。电催化结果表明P-CoS具有最低的过电位和最小的塔菲尔斜率。这种空位工程策略也为活性材料提供了新的见解，应该有利于下一代储能装置的设计。
