Spectroscopic Investigation of the Effect of Microstructure and Energetic Offset on the Nature of Interfacial Charge Transfer States in Polymer: Fullerene Blends.

ABSTRACT: Despite performance improvements of organic photovoltaics, the mechanism of photoinduced electron-hole separation at organic donor-acceptor interfaces remains poorly understood. Inconclusive experimental and theoretical results have produced contradictory models for electron-hole separation in which the role of interfacial charge-transfer (CT) states is unclear, with one model identifying them as limiting separation and another as readily dissociating. Here, polymer-fullerene blends with contrasting photocurrent properties and enthalpic offsets driving separation were studied. By modifying composition, film structures were varied from consisting of molecularly mixed polymer-fullerene domains to consisting of both molecularly mixed and fullerene domains. Transient absorption spectroscopy re

SUBMITTER: Dimitrov SD 

PROVIDER: S-EPMC6429453 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature