Stepwise Preparation of Linear π-Conjugated Bis(terpyridine)metal Polymer Chains at Gold Surface

Defect-free structures of a film composed of linear redox polymer chains were prepared using stepwise complexation of Fe(II) and/or Co(II/III) ions with azobenzene-bridged bis(tpy) (tpy = 2,2′:6′,2″-terpyridine) ligands, tpy–AB–tpy, on tpy-terminated SAM on gold. This method realizes a formation of desired number of polymer units (for example, 47-mer of Co(tpy)2) and a desired sequence of Co–Fe heterometal structures in the polymer chain (for example, 10-mer of Co(tpy)2 plus 5-mer of Fe(tpy)2).