Photoelectrochemical solar cells using [(dcbH2)2 RuLL′], L,L′ = substituted pyridines, as nanocrystalline TiO 2 sensitizers

Abstract

The development of thin-layer transparent solar cells based on dye sensitization of nanocrystalline n-type TiO2 undertaken at the Laboratory of Inorganic Photochemistry and Energy Conversion at the Chemistry Institute of Universidade de São Paulo is presented. Compounds of the formula cis-[(dcbH2)2RuLL′], dcbH2 = 4,4′-(CO2H)2-2,2′-bipyridine and L/L′ = substituted pyridines, have been successfully employed as molecular sensitizers in photoelectrochemical solar cells based on dye-sensitization of n-TiO 2. This regenerative solar cell consists of a TCO glass with a dye-sensitized TiO2 semiconductor film as a photoanode, I 2/LiI solution in acetonitrile as a redox mediator and a transparent Pt coated TCO glass as a counter electrode. Efficient conversion of visible light into electricity was achieved with IPCE (Incident Photon-to-Current Conversion Efficiency) as high as 50% between 400 and 550 nm.