Synthesis of novel multi-chromophoric soluble perylene derivatives and their photosensitizing properties with wide spectral response for SnO2 nanoporous electrode

Two series of new multi-chromophoric perylene-3,4:9,10-tetracarboxylic dian hydride dyes for solar cell sensitizers have been synthesized. One series c onsists of oxadiazole or naphthaldicarboximide that are linked with perylen e units as N,N'-substituted chromophores. The other series has four substit uents in the bay-region of the perylene core in addition to N,N'-substituen ts. These novel routes to highly efficient sensitizers for Gratzel-type sol ar cells avoid the complication of doping. A wide spectral photoresponse (f rom 310 to 700 nm) was observed with maximum IPCE (incident photon-to-curre nt efficiency) of 24%. In addition, the sensitization is dependent on the e nergy match of the energy bands of the semiconductor and the redox potentia l of the segments in such assembled dyes.