fig14

Figure 14. (A) Wireframe view of unit cell structure of cobalt phosphonate (PC1) along an axis, with dotted lines showing H-bonding among the chains (B). Polyhedron view of unit cell of PC1, with hydrogen atoms omitted for clarity and the red dots showing free water molecules. (C) Cycling stability diagram of PC1. (D) Comparison of cycling stability of C₁₅H₃₂N₃Ni₂O₁₆P (PN1), C₁₅H₃₂Co₂N₃O₁₆P (PC1) and C₃₀H₅₀N₆Ni_2.67Co_1.33O₂₇P₂ (PNC). Reproduced with permission from Ref.^[194] (Copyright 2019, Electrochemica Acta, Elsevier).