F?rster Resonance Energy Transfer Sensitized Singlet Fission in BODIPY-Pentacene Dimer Conjugates

摘要

In the present work, the energy donor 4,4-difluoro-4-bora-3a,4a-diaza-sindacene(BODIPY) is used for the first time in combination with a pentacenedimer (Pnc_2) to provide the conjugate BODIPYPnc_2 that features absorptionthroughout a large part of the solar spectrum. Upon photoexcitation, thesinglet excited state energy of BODIPY is transferred to the pentacene dimervia intramolecular F?rster resonance energy transfer (FRET). Subsequently,the pentacene dimer undergoes intramolecular singlet fission. In this process,a singlet correlated triplet pair is generated from the first singlet excited statevia coupling to an intermediate state. The results show that solvent polarityhas an influence on the system, with the largest FRET rate (i.e., 7.46 × 10~（11）s~（?1）) being obtained in the most polar solvent (namely, benzonitrile) alongwith the largest triplet quantum yield (i.e., 207 ± 20).