Highly efficient co-sensitization of nanocrystalline TiO2 electrodes with plural organic dyes

Abstract
Through cooperative interactions, each of the three organic dyes utilized achieved improved sensitizing abilities on nanocrystalline TiO2 electrodes in co-sensitization over single-dye-sensitization, which led to a wide (400–700 nm) and highly efficient (exceeding 70%) photocurrent action spectrum in triple-dye-sensitization and an overall power conversion efficiency (η) of 6.5% (AM1.5, 80 mW cm−2), the highest η to date for dye-sensitized solar cells (DSSCs) based on the co-sensitization of plural organic dyes, fully demonstrating the potential of co-sensitization in DSSC applications.