Oriented Assembly of 2D Metal‐Pyridylporphyrinic Framework to Regulate the Redox Kinetics in Li−S Batteries

Abstract Developing the highly efficient catalysts is a great challenge for accelerating the redox reactions in Li−S batteries. Inspired by the single‐atom catalysts and metalloproteins, it makes full use of the advantages of metal–organic frameworks (MOFs) as electrocatalysts. Herein, a series of 2D metal‐bonded metalloporphyrin MOFs are prepared with 5,10,15,20‐tetrakis(4‐pyridyl) cobalt porphyrin (CoTPyP) as building blocks and transition metals (M═Mn, Fe, Co, Ni, and Cu) as nodes, respectively. The crystalline structures of the bimetallic 2D MOFs are confirmed by UV–vis spectra and X‐ray diffraction analyses. According to DFT calculation, the peripheral metal nodes optimize the electronic state of Co in porphyrin core. Especially, CoTPyP‐Mn facilitates the cleavage of S−S bond from both ends and promotes their conversion kinetics through Co−S and Li−N bonds. The Li−S cells with CoTPyP‐Mn show the initial specific capacity of 1339 mA h g −1 at 0.2 C. The capacity decay rate is only 0.0442% per cycle after 1000 cycles at 2 C. This work achieves the rational control of the central Co d electron state through the peripheral regulation and enriches the application of MOFs in accelerating the redox kinetics in Li−S batteries.