Lv Shenshen, Yuan Jingjun, Chen Zhi, Gao Ping, Shu Hongbo, Yang Xiukang, Liu Enhui, Tan Songting, Ruben Mario, Zhao-Karger Zhirong, Fichtner Maximilian
Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, Key laboratory for Green Organic Synthesis and Application of Hunan Province, College of Chemistry, Xiangtan University, 411105, Xiangtan, P.R. China.
Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, 76021, Karlsruhe, Germany.
ChemSusChem. 2020 May 8;13(9):2286-2294. doi: 10.1002/cssc.202000425. Epub 2020 Apr 17.
Rechargeable potassium-ion batteries (KIBs) are promising alternatives to lithium-ion batteries for large-scale electrochemical energy-storage applications because of the abundance and low cost of potassium. However, the development of KIBs is hampered by the lack of stable and high-capacity cathode materials. Herein, a functionalized porphyrin complex, [5,15-bis(ethynyl)-10,20-diphenylporphinato]copper(II) (CuDEPP), was proposed as a new cathode for rechargeable potassium batteries. Spectroscopy and molecular simulation studies were used to show that both PF and K interact with the porphyrin macrocycle to allow a four-electron transfer. In addition, the electrochemical polymerization of the ethynyl functional groups in CuDEPP resulted in the self-stabilization of the cathode, which was highly stable during cycling. This unique charge storage mechanism enabled CuDEPP to provide a capacity of 181 mAh g with an average potential of 2.8 V (vs. K /K). These findings could open a pathway towards the design of new stable organic electrodes for KIBs.
可充电钾离子电池（KIBs）因其钾资源丰富且成本低，有望成为锂离子电池在大规模电化学储能应用中的替代方案。然而，KIBs的发展受到缺乏稳定且高容量阴极材料的阻碍。在此，一种功能化卟啉配合物，[5,15 - 双（乙炔基）- 10,20 - 二苯基卟吩铜（II）]（CuDEPP），被提议作为可充电钾电池的新型阴极。光谱学和分子模拟研究表明，PF⁻和K⁺都与卟啉大环相互作用，从而实现四电子转移。此外，CuDEPP中乙炔基官能团的电化学聚合导致阴极的自稳定，使其在循环过程中高度稳定。这种独特的电荷存储机制使CuDEPP能够提供181 mAh g⁻¹的容量，平均电位为2.8 V（相对于K⁺/K）。这些发现可能为设计用于KIBs的新型稳定有机电极开辟一条途径。
