fig4

Figure 4. (A) Schematic illustration of structure, phase transitions, and corresponding reaction mechanisms for P2-Na_0.67CoO₂ and P2-Na_0.6Co_0.78Ru_0.22O₂; (B) Electrochemical performance of P2-Na_0.67CoO₂ and P2-Na_0.6Co_0.78Ru_0.22O₂. Reproduced with permission, Copyright 2023^[70], Wiley-VCH; (C) Schematic illustration of the synthesis of P2-Na_2/3Mn_1/2Ni_1/6Co_1/3O₂; (D) Cycling stability of P2-Na_2/3Mn_1/2Ni_1/6Co_1/3O₂; (E) Schematic illustration of the phase transitions for P2-Na_2/3Mn_xNi_x−1/3Co_4/3−2xO₂ (1/3 ≤ x ≤ 2/3). Reproduced with permission, Copyright 2021^[77], Wiley-VCH; (F) Voltage profiles and electrochemical performance of Ti-substituted and Ti-Zn-substituted P2 cathodes; (G) Selected operando XRD patterns and schematic illustrations of structural change mechanisms for these cathodes. Reproduced with permission, Copyright 2023^[86], Wiley-VCH.