We describe a new generation of perylene photosensitizers based upon N-(2,5-di-tert-butylphenyl)perylene-3,4-dicarboximide. The new sensitizers have more favorable energetics for electron injection into TiO2 and better light absorption properties for solar conversion than previous sensitizers based upon perylene tetracarboxylic acid dianhydride. Syntheses, absorption properties, and electrochemical potentials for the new perylenes are reported. We compare the solar conversion efficiencies of the dyes in the dye sensitized solar cell (DSSC) and discuss trends in terms of energetics and structural differences that may affect the injection and recombination processes. These are the highest efficiencies yet reported for perylene sensitizers in the DSSC.
Supercritical carbon dioxide as a solvent for deposition of a tailored dye in dye sensitized solar cells
作者:Subashani Maniam、Andrew B. Holmes、Julia Krstina、Gary A. Leeke、Gavin E. Collis
DOI:10.1039/c1gc15864c
日期:——
We report a new technique whereby dyes can be deposited onto metal oxide surfaces using supercritical carbon dioxide (scCO2) for use in solar cell applications. This process eliminates the need for hazardous organic solvents and waste solvents generated during the dyeing process. The solubility of a perylene anhydride dye in scCO2 is enhanced by the incorporation of fluorinated alkyl subsituents and the use of masked carboxylic binding groups. This allows fast deposition of the dye onto the TiO2 photoanode, resulting in efficient photovoltaic performance. The unreacted dye is then easily recovered in a solid form after the deposition process by venting the carbon dioxide.