Oxygen catalytic reactions, paramagnetic

The authors proposed a catalytic cycle in which Co(ll)-water moieties undergo proton coupled oxidation, with phosphate being the proton acceptor, to form adjacent Co(IV)-oxo units, finally responsible for oxygen generation [58]. Important insights on the reaction mechanism come from Electron Paramagnetic Resonance (EPR) evidence of low-spin Co(IV) formation (geu = 2.27) upon preparation of the film at potentials of 1.14 and 1.34 V [59]. 

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