Bio-inspired noble-metal-free supramolecular systems were constructed by host-guest inclusions of an FeFe-hydrogenase mimic and an organic dye into cyclodextrins respectively, which give typically a ninefold increase in the TON, a sixteenfold enhancement in the quantum efficiency, and a threefold extension in lifetime as compared to the same system in the absence of cyclodextrin for photocatalytic H 2 production in aqueous solution.

A [FeFe]-hydrogenase model (1) containing a chelating diphosphine ligand with a pendant amine was readily oxidized by Fc(+) (Fc = Cp2Fe) to a Fe(II)Fe(I) complex ([1](+)), which was isolated at room temperature. The structure of [1](+) with a semibridging CO and a vacant apical site was determined by X-ray crystallography. Complex [1](+) catalytically activates H2 at 1 atm at 25 °C in the presence of excess Fc(+) and P(o-tol)3. More interestingly, the catalytic activity of [1](+) for H2 oxidation remains unchanged in the presence of ca. 2% CO. A computational study of the reaction mechanism showed that the most favorable activation free energy involves a rotation of the bridging CO to an apical position followed by activation of H2 with the help of the internal amine to give a bridging hydride intermediate.

We synthesized a new MXene/PANI composite by chemical oxidative polymerization of aniline monomers with enhanced electrochemical performances.