Hydrogen evolution from aqueous solution mediated by a heterogenized [NiFe]-hydrogenase model: low pH enables catalysis through enzyme-relevant mechanism.
Résumé
[NiFe]-hydrogenase enzymes are efficient catalysts for H2 evolution but their synthetic models have not been reported to be active under aqueous conditions, so far. Here we show that a close model of the [NiFe]-hydrogenase active site can work as a very active and stable heterogeneous H2 evolution catalyst under mildly acid aqueous conditions. Entry in catalysis is a NiIFeII complex, with electronic structure analogous to the Ni-L state of the enzyme, corroborating the mechanism modification recently proposed for [NiFe]-hydrogenases.