Highly efficient charge transfer from a trans-ruthenium bipyridine complex to nanocrystalline TiO2 particles

Abstract

trans-Di(isothiocyanato)-[N-bis(2,2′-bipyridyl-4,4′-dicarboxylic acid) ruthenium(II) acts as a very efficient charge-transfer sensitizer for nanocrystalline TiO₂ films. The incident photon-to-electron conversion efficiency (IPCE) for the dye-coated TiO₂ film exceeded 80% in the wavelength domain between 400 and 600 nm. A sandwich-type regenerative solar cell fabricated from a 10 μm thick TiO₂ film sensitized with this dye generated a short-circuit photocurrent of 19.6 mA cm⁻² and an open-circuit photovoltage of 720 mV in simulated AM1.5 solar light (924 W m⁻²) with an overall power conversion efficiency of 8.6%.