Reactivity of Ruthenium Coordination Compounds on Titanium Oxide Surfaces: Catalysis on a Film

PHILLIPS, KATHERINE; CADRANEL, ALEJANDRO; GAITÁN, MARTÍN; BARALDO, LUIS

Campinas, Brasil

Workshop; Presentación de resultados del programa Research Experience for Undergraduates (REU); 2009

UNICAMP - Programa REU

Titanium oxide can be put on glass/ITO (indium tin oxide) electrodes as a mesoporous film, with control of the size of the pores. Because carbonyls bind strongly to TiO2 in an essentially irreversible reaction, compounds with a carbon-oxygen double bond can bind to the surface and fill the pores in this film, allowing for more surface area. Bis-bipyridine complexes of Ruthenium have already been studied as catalysts for water oxidation (with OH2 at the other binding sites), and for light-sensitive release of pyridine (with pyridine at the other two binding sites). These have several implications; water oxidation is an important area of research for finding energy alternatives, and the bis-pyridine complex mimics neurotransmitters and has biological applications. Using the quinone 1,10-phenanthroline-5,6 dione in place of bipyridine, the carbonyl of the ligand can bind to a TiO2 surface. This leaves four open sites on Ruthenium, which can be filled to mimic the solution chemistry already extensively studied, but on a surface with a built-in electrode.