Ni (II), with its d 8 electronic configuration, exhibits a distinct reactivity profile toward oxygen, largely influenced by its electronic structure and coordination environment . The fully filled t2g orbitals and partially occupied eg orbitals allow Ni (II) to stabilize oxygen intermediates through σ-donation and π-back donation mechanisms. Unlike Co (II), Ni (II) typically operates in a low-spin configuration, resulting in fewer unpaired electrons and a slightly reduced direct affinity for paramagnetic oxygen. However, the higher ligand field stabilization energy in Ni (II) complexes can create a favorable environment for oxygen binding and activation . The interplay between ligand field effects and the d-orbital alignment in Ni (II) enhances its ability to stabilize peroxide and superoxide species, making it a critical player in catalytic processes involving oxygen, including ORR. This unique electronic framework enables Ni (II) to function effectively in synergistic catalytic systems, particularly when paired with complementary metal centers.