Proton switching as a driving force for the metal–organic complex-mediated growth of gold colloids

Abstract

A mono-protonated (bis(4′-(4-pyridyl)-2,2′:6′,2′′-terpyridine)iron(II)) complex [[Fe(ptpy)(Hptpy)](PF₆)₃] acts as a structure directing agent for larger gold colloids in the present investigation. We report here a H-bonded [Fe(ptpy)(Hptpy)](PF₆)₃ complex acting as an inter-linker for the complex-mediated growth of gold nanoparticles. This exploration discusses the possibility of proton switching in [Fe(ptpy)(Hptpy)](PF₆)₃, which can interconvert the oxidation state of Fe between +2 and +3 at the interface of citrate-capped gold nanoparticles, enabling the complex-mediated growth of geometry-specific, large size gold colloids.