fig7

Figure 7. (A) The Zn²⁺ storage mechanism of the C4Q cathode. Reproduced with permission^[30]. Copyright 2018, AAAS; (B) The Zn²⁺ storage mechanism of the PDBS-Zn. Reproduced with permission^[69]. Copyright 2021, Wiley Online Library; (C) Cycling performance of NTCDI cathode. Reproduced with permission^[67]. Copyright 2019, Wiley Online Library; (D) Cycling performance of BT-PTO COF cathode under 5 A·g^-1. Reproduced with permission^[75]. Copyright 2022, Wiley Online Library. C4Q: Calix[4]quinone; PDBS: poly(2,5-dihydroxy-1,4-benzoquinonyl sulfide); NTCDI: 1,4,5,8-naphthalene diimide; BT-PTO: benzenetricarboxaldehyde pyrene-4,5,9,10-tetraone; COF: covalent-organic frameworks.