Influence of the backbone of N5-pentadentate ligands on the catalytic performance of Ni(ii) complexes for electrochemical water oxidation in neutral aqueous solutions.

Two N5-chelated nickel complexes displayed decent catalytic activity and good stability for electrochemical water oxidation in phosphate buffer solutions at pH 7, with observed rate constants of 3.06 and 4.62 s-1, which are higher than those reported so far for molecular nickel catalysts in neutral solutions. The results revealed that the rigid backbone of N5-chelating ligands has a positive influence on the activity of the nickel catalysts.