fig9

Figure 9. (A) Cycling performance at various current densities. Reproduced with permission from Ref.^[75] (Copyright 2022, Wiley-VCH GmbH). (B) The corresponding energy barrier reducing mechanism, E_g is the intrinsic excitation energy of Li₂O₂, eU is the interfacial charge transfer (ICT) barrier; electrochemical performances of the Li-O₂ battery with 0 FC or 100 FC cathode. (Different amounts (0, 100 mg, 200 mg) of tetrafluoroterephthalic acid were used to adjust the content of doped F, and the corresponding products were denoted as 0 FC, 100 FC, and 200 FC, respectively.) Reproduced with permission from Ref.^[18] (Copyright 2022, Elsevier). (C) Ni^III-NCF and Ni^II-NCF cathode discharge mechanisms. Reproduced with permission from Ref.^[77] (Copyright 2021, Wiley-VCH GmbH). (D) preparation of the flexible hybrid free-standing film using a layer-by-layer approach. Reproduced with permission from Ref.^[19] (Copyright 2021, Elsevier).