Visible photosensitization of TiO2 — Photodegradation of CCl4 in aqueous medium

A new ruthenium (II) complex, [Ru(terpy-Ph---PO3H2)2]2+ (where terpy-Ph---PO3H2 = 4′-(p-phosphonophenyl)-2,2′:6,2″-terpyridine), has been synthesized for the photosensitization of anatase TiO2 towards the visible spectrum. The sensitizer is able to establish strong anchorage on the surface of the TiO2 over a wide pH range. Under broad band visible irradiation, the sensitizer can inject electrons into the conduction band of the semiconductor. Using I− as electron donor, the TiO2-[Ru(terpy-Ph---PO3H2)2]2+ system is able to mediate degradation of CCl4 in aqueous medium.