Wang Junhao, Jia Hongfeng, Liu Zhaoli, Yu Jie, Cheng Linqi, Wang Heng-Guo, Cui Fengchao, Zhu Guangshan
Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education and Faculty of Chemistry, Northeast Normal University, Changchun, 130024, P. R. China.
Adv Mater. 2024 Feb;36(6):e2305605. doi: 10.1002/adma.202305605. Epub 2023 Dec 7.
Potassium-ion batteries (PIBs) are gradually gaining attention owing to their natural abundance, excellent security, and high energy density. However, developing excellent organic cathode materials for PIBs to overcome the poor cycling stability and slow kinetics caused by the large radii of K ions is challenging. This study demonstrates for the first time the application of a hexaazanonaphthalene (HATN)-based 2D π-d conjugated metal-organic framework (2D c-MOF) with dual-active centers (Cu-HATNH) and integrates Cu-HATNH with carbon nanotubes (Cu-HATNH@CNT) as the cathode material for PIBs. Owing to this systematic module integration and more exposed active sites with high utilization, Cu-HATNH@CNT exhibits a high initial capacity (317.5 mA h g at 0.1 A g ), excellent long-term cycling stability (capacity retention of 96.8% at 5 A g after 2200 cycles), and outstanding rate capacity (147.1 mA h g at 10 A g ). The reaction mechanism and performance are determined by combining experimental characterization and density functional theory calculations. This contribution provides new opportunities for designing high-performance 2D c-MOF cathodes with multiple active sites for PIBs.
钾离子电池（PIBs）因其天然丰度高、安全性好和能量密度高而逐渐受到关注。然而，开发用于PIBs的优异有机阴极材料以克服由K离子半径大导致的循环稳定性差和动力学缓慢的问题具有挑战性。本研究首次展示了具有双活性中心的基于六氮杂萘（HATN）的二维π - d共轭金属有机框架（2D c - MOF）（Cu - HATNH）的应用，并将Cu - HATNH与碳纳米管（Cu - HATNH@CNT）集成作为PIBs的阴极材料。由于这种系统的模块集成以及更多暴露的高利用率活性位点，Cu - HATNH@CNT表现出高初始容量（在0.1 A g时为317.5 mA h g）、优异的长期循环稳定性（在5 A g下2200次循环后容量保持率为96.8%）和出色的倍率性能（在10 A g时为147.1 mA h g）。通过结合实验表征和密度泛函理论计算确定了反应机理和性能。这一贡献为设计具有多个活性位点的用于PIBs的高性能二维c - MOF阴极提供了新的机会。
