Photoinduced charge separation and charge recombination in the [60]fullerene-diphenylbenzothiadiazole-triphenylamine triad: role of diphenylbenzothiadiazole as bridge.

Photoinduced electron-transfer processes of the newly synthesized [60]fullerene-diphenylbenzothiadiazole-triphenylamine (C60-PBTDP-TPA) triad in polar and nonpolar solvents have been studied by using time-resolved transient absorption and fluorescence measurements from picosecond to microsecond regions. By fluorescence lifetime measurements in picosecond time regions, excitation of the charge-transfer transition of the PBTDP-TPA moiety in C60-PBTDP-TPA induces energy transfer to the C60 moiety generating 1C60*-PBTDP-TPA, competitively with charge separation generating C60*--PBTDP-TPA*+. From 1C60*-PBTDP-TPA, which is generated directly and indirectly, charge separation occurs generating C60*--PBTDP-TPA*+ in polar solvents.

Self-assembling of n-type semiconductor tri(phenanthrolino)hexaazatriphenylenes with a large aromatic core.

[reaction: see text] Large disk-shaped aromatic tri(phenanthrolino)hexaazatriphenylenes 5a, 5b, and 5c with six butyl, dodecyl, and 4-octylphenyl groups, respectively, were self-assembled both in solution and film state to form one-dimensional aggregates. Their n-type semiconducting nature was indicated from CV measurement, in which the first reduction potentials were evaluated at around -1.7 V (vs Fc/Fc(+)) in dichloromethane.