About half of the thus far reported covalent organic frameworks (COFs) are of imine-linked 2D and 3D structures, which usually suffer from relatively low working stability due to the vulnerable easily nucleophile-attacked C=N bond nature. Herein, an imine-linked 3D COF, TAM-DMPZD-COF, was constructed by reaction between 4-connected Td 4,4′,4′',4′''-methanetetrayltetraaniline and 2-connected 5,10-methyl-5,10-dihydrophenazine-2,7-dicarbaldehyde. Addition of S8 into the above mentioned reaction leads to the transformation of imine bond into an aromatic thiazole moiety in the framework, affording the thiazole-linked 3D COF, TAM-DMPZD-COF-S. This result in significant enhancement over the ultrahigh cycling stability of the TAM-DMPZD-COF-S-based LIBs cathode, with the thus far reported highest 50000 cycles and 0.00016% capacity decay per cycle at 10 A g-1, in good contrast to only 55% capacity retention after 5000 cycles at 10 A g-1 for TAM-DMPZD-COF-based LIBs cathode. Nevertheless, transformation of imine bond into an aromatic thiazole moiety in the 3D framework also induces an increase in the redox active sites for both Li+ and PF6- ions, resulting in enhanced ion storage capacity and energy density of TAM-DMPZD-COF-S (325 mA h g-1 and 736 W h kg−1 at 0.1 A g-1), surpassing those for traditional inorganic cathodes and all the thus far reported COFs-based electrodes.
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