Synthesis, characterisation, and photochemical properties of a series of ruthenium containing metallopolymers based on poly-N-vinylimidazole

Abstract
A series of polymeric materials has been prepared by treating poly-N-vinylimidazole (pnvi) with hydrated bis(2,2′-bipyridyl)ruthenium dichloride. The mole ratio of poly-N-vinylimidazole to [Ru(bipy)2Cl2]·2H2O(pnvi:Ru ratio) was varied from 5: 1 to 50: 1. From spectroscopic and electrochemical studies, both in solution and as thin films, it is shown that depending on the reaction conditions, different types of ruthenium–pnvi complexes are formed. The spectroscopic and electrochemical properties of the metallopolymers obtained are compared to those of mononuclear N-methylimidazole compounds of bis(2,2′-bipyridyl)ruthenium(II). An unusual, photochemically induced, reversible ligand-exchange process is observed for thin polymer layers in sulphuric acid.