An alternately introduced heterometallo-supramolecular polymer: synthesis and solid-state emission switching by electrochemical redox.

By utilizing different coordination properties of a lanthanide ion and a transition metal ion, a heterometallo-supramolecular polymer with Eu(III) and Fe(II) ions introduced alternately (polyEuFe) was precisely prepared via stepwise complexation of the metal ions to a new unsymmetrical ligand with both a dicarboxylate-substituted terpyridine and an unsubstituted terpyridine. The polymer showed unique, reversible "on-off" switching of the Eu(III) luminescence by electrochemical redox of the Fe ions in the solid-state.