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Iron(III)-superoxo intermediates are believed to play key roles in oxygenation reactions by non-heme iron enzymes. We now report that a non-heme iron(II) complex activates O(2) and generates its corresponding iron(IV)-oxo complex in the presence of substrates with weak C-H bonds (e.g., olefins and alkylaromatic compounds). We propose that a putative iron(III)-superoxo intermediate initiates the O(2)-activation chemistry by abstracting a H atom from the substrate, with subsequent generation of a

Hydrogen peroxide, which is a green oxidant and fuel, is produced by a two-electron/two-proton reduction of dioxygen, two-electron/two-proton oxidation of water, or a combination of four-electron/four-proton or/and two-electron/two-proton oxidation of water and two-electron/two-proton reduction of dioxygen. There are many reports on electrocatalysts for selective two-electron/two-proton reduction of dioxygen to produce hydrogen peroxide instead of four-electron/four-proton reduction of dioxygen

Electron-transfer kinetics for the reduction of non-heme oxoiron(IV) complexes by a series of ferrocene derivatives were examined in deaerated acetonitrile, and the resulting data were evaluated in light of the Marcus theory of electron transfer to determine the reorganization energies of electron transfer and the one-electron reduction potentials of non-heme oxoiron(IV) complexes. The electron-transfer properties of non-heme oxoiron(IV) complexes are featured by the larger reorganization energi

Seawater is the most abundant resource on our planet and fuel production from seawater has the notable advantage that it would not compete with growing demands for pure water. This Review focuses on the production of fuels from seawater and their direct use in fuel cells. Electrolysis of seawater under appropriate conditions affords hydrogen and dioxygen with 100 % faradaic efficiency without oxidation of chloride. Photoelectrocatalytic production of hydrogen from seawater provides a promising w

The catalytic conversion of CO₂ into valuable chemicals and fuels has attracted increasing attention, providing a promising route for mitigating the greenhouse effect of CO₂ and also meeting the global energy demand. Among many homogeneous and heterogeneous catalysts for CO₂ reduction, this mini-review is focused on heme and nonheme metal complexes that act as effective catalysts for the electrocatalytic and photocatalytic reduction of CO₂. Because met

Abstract The two‐electron reduction of dioxygen with two protons produces hydrogen peroxide, which is directly used as a liquid fuel in hydrogen peroxide fuel cells, whereas the four‐electron reduction of dioxygen is combined with the two‐electron oxidation of hydrogen in hydrogen fuel cells. Platinum (Pt)‐based nanocomposites are the most efficient commercial electrocatalysts for the oxygen reduction reaction (ORR). However, the poor stability, scarcity and high cost of these Pt‐based oxygen el

Give me an "O"! Mononuclear nonheme iron(IV) oxo complexes have been generated using water as an oxygen source and cerium(IV) as an oxidant. The high-yield oxygenation of organic substrates in this system (see picture, Fe green, O red, N blue, C gray) is catalyzed by iron(II) complexes. The source of oxygen in the iron(IV) oxo complexes and the oxygenated products has been assigned unambiguously by isotopic labeling experiments.

Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating reactivities of oxygen-containing metal complexes in a variety of biological and biomimetic reactions, including dioxygen activation/formation and functionalization of organic substrates. Mononuclear nonheme iron(III)-peroxo species are invoked as active oxygen intermediates in the catalytic cycles of dioxygen activation by nonheme iron enzymes and their biomimetic compounds. Here, we report mononuclear nonhe