Photophysics of semiconducting polymer- C/sub 60/ composites: a comparative study

Summary form only given. Experimental results on the metastable, reversible, ultrafast photoinduced electron transfer between semiconducting, conjugated polymers and buckminsterfullerene, C/sub 60/, are summarized. Comparative studies with different semiconducting polymers as donors demonstrate that in the degenerate ground state polymers soliton excitations form before the electron transfer can occur; thereby inhibiting charge separation. In non-degenerate ground state systems, photoinduced electron transfer occurs in less than 10/sup -12/ s, quenching the photoluminescence as well as the intersystem crossing. The hindrance of the photoelectron transfer by strongly Coulomb correlated photoexcitations (excitons) formed at the donor polymer is demonstrated with polydiacetylenes. The results are discussed in terms of opportunities for solar energy conversion, for photodiode detector devices, and for a variety of other applications which use photoinduced charge separation like in the photosynthesis.