Eapplied = potential at which HER occurs Eeq = Equilibrium potential Co (II) exhibits a remarkably low overpotential (1.054257189511323e-25 eV), suggesting it could function as an ideal catalyst for the HER. This efficiency can be attributed to Co (II)'s ability to form stable tetradentate Schiff base ligands, which provide a highly favorable coordination environment. Schiff bases, known for their excellent electrochemical properties, facilitate efficient electron transfer and stabilize the Co (II) active center during the reaction. These features not only enhance the intrinsic catalytic activity of cobalt but also improve its durability, making Schiff basemodified Co (II) complexes promising candidates for HER.