Enhanced adsorption of cis-Cl2 bis(2,2′-bipyridyl) ruthenium(II) on nanocrystalline TiO2 electrode in the presence of poly(4-vinyl-pyridine)

The effect of poly(4-vinyl-pyridine) (PVP) on the adsorption behavior of cis-Cl2 bis(2,2′-bipyridyl) ruthenium(II) (RuL2Cl2), lack of carboxyl groups, on nanocrystalline TiO2 film was investigated. It is found that the maximum amount of RuL2Cl2 adsorbed by TiO2 with PVP, 5 × 10−10 mol/cm2, is 30 times higher than that of RuL2Cl2 adsorbed by TiO2 without PVP. The interaction between PVP and RuL2Cl2 was characterized by IR and UV–vis. The effect of adsorption time on the amount of RuL2Cl2 with PVP was also investigated. The role of PVP in the adsorption of RuL2Cl2 was explained and the structure of RuL2Cl2 and PVP on nanocrystalline TiO2 film surface was supposed.