Comparative study of the anchorage and the catalytic properties of nanoporous TiO2 films modified with ruthenium (II) and rhenium (I) carbonyl complexes.

In this article we study the anchoring of cis-[Ru(bpyC 4 pyr)(CO) 2 (CH 3 CN) 2 ] 2+ , cis-[Ru(bpy) 2 (CO) 2 ] 2+ and cis-[Ru(bpyac)(CO) 2 Cl 2 ], onto nanoporous TiO 2 employing electropolymerization, electrostatic interaction and chemical bonding. Also, the [Re(bpyac)(CO) 3 Cl] rhenium(I) complex for chemical anchorage was analyzed. The characterization of TiO 2 /Ru(II) and TiO 2 /Re(I) nanocomposite films was performed by field emission scanning electron microscopy (FESEM), electron dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. In addition, for the more stable nanocomposites obtained, the catalytic properties (solar energy conversion and CO 2 reduction) were evaluated. The efficiency improvement in redox process derived from the (photo)electrochemical evidence indicates that modified nanoporous TiO 2 structures enhance the rate of charge transfer reactions. [ABSTRACT FROM AUTHOR]