Donor-acceptor interaction of zinc(II) with molecular oxygen in aqueous solutions of NaClO4 and NaNO3

Interactions of Zn(II) ions with molecular oxygen in 0.1 M NaClO 4 or 0.1 M NaNO 3 were studied by ac voltammetry using a stationary dropping mercury electrode. The formation of five nZn mO 2 complexes (where n = I, m = 1, 2, or 3 and m = 1, n = 1, 2, or 4) was found to be possible. Molecular oxygen is electroactive in all the complexes; the reduction of O 2 is impeded for n = 1 and m = 3 and facilitated for n = 4 and m = 1 compared to its reduction in the absence of zinc(II). When oxygen in the resulting complexes is reduced according to the first two-electron step, Zn 2 + ions are active in the 2: 1 and 4: 1 complexes and inactive in the 1: 1, 1: 2, and 1: 3 complexes.