Photochemical behavior of intercalation compounds of layered niobates with methylvilologen

Intercalation compounds of three layered niobates with methylviologen (1, 1'-dimethyl-4,4'-bipyridinium ion) were synthesized and their photochemical behavior was investigated. All the host niobates successfully intercalated methylviologen dications, and there were structural differences among the samples. UV irradiation of the intercalation compounds caused photoinduced electron transfer from the hosts to the guest to form methylviologen radical cations. The radical cations were characterized by their high stability, which had a relation to the structure of the intercalation compounds. Co-intercalation of photochemically inactive ions (K₊ or propylammonium ions) with methylviologen extremely well stabilized the radical cations.