Immobilization of a non-heme diiron complex encapsulated in an ammonium-type ionic liquid layer modified on an Au electrode: reactivity of the electrode for O2 reduction.

An unstable diiron(II,II) complex possessing O2 binding ability at low temperature was encapsulated and stabilized in an ammonium-type ionic liquid layer polymerized on an electrode. The encapsulated complex revealed catalytic reactivity for four-electron reduction of O2 at an ambient temperature in aqueous solution.