Polaron pair mediated triplet generation in polymer/fullerene blends.

ABSTRACT: Electron spin is a key consideration for the function of organic semiconductors in light-emitting diodes and solar cells, as well as spintronic applications relying on organic magnetoresistance. A mechanism for triplet excited state generation in such systems is by recombination of electron-hole pairs. However, the exact charge recombination mechanism, whether geminate or nongeminate and whether it involves spin-state mixing is not well understood. In this work, the dynamics of free charge separation competing with recombination to polymer triplet states is studied in two closely related polymer-fullerene blends with differing polymer fluorination and photovoltaic performance. Using time-resolved laser spectroscopic techniques and quantum chemical calculations, we show that lower charge se

SUBMITTER: Dimitrov SD 

PROVIDER: S-EPMC4366531 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature