Dye Sensitization of Nanocrystalline Tin Oxide by Perylene Derivatives

Abstract

A new sensitizing dye−semiconductor system comprised of perylene derivatives on SnO2 has been characterized. The tetracarboxylic acid form (“PTCA”) of the commercially available dye perylene-3,4,9,10-tetracarboxylic dianhydride and the novel compound perylene-3,4-dicarboxylic acid-9,10-(5-phenanthroline)carboximide (“PPDCA”) adsorb strongly to the surface of colloidal films of SnO2 and inject electrons into the semiconductor film upon absorption of light. A film of PPDCA on SnO2 yields a short circuit photocurrent density of 3.26 mA/cm2, a photovoltage of −0.45 V, and an overall cell efficiency of 0.89% at one sun light intensity. Estimates of the oxidation potential of adsorbed PPDCA indicate that it may also be useful in a water-splitting configuration. The results presented here indicate that the perylene−SnO2 system is a promising dye−semiconductor combination and warrants further study.