Bioinspired and electrochemical approach of O2 reductive cleavage. Towards new and efficient catalysts for O2 reduction into H2O.

摘要: The catalytic four-electron (4e−) reduction of O2 to H2O has merited increasing attention because it is an intrinsic fuel cells technology. The high loadings of Pt required to achieve appreciable activity have prompted the development of catalysts based on nonprecious metals such as Mn or Fe. Natural systems, capable of O2 transformation and using non-precious metals provide a rich source of inspiration. The key intermediate for the catalytic 4e− reduction of O2 is regarded to be a metal− peroxo complex, which is further reduced to H2O. We present here the reactivity and mechanistic studies of a Mn-peroxo species. The results reveal dichotomy of Mn–O vs. O–O bond cleavages unprecedented for Mn (III)-peroxo complexes and offer a route for electrochemical O2 reduction by Mn complexes.