Benzazole (B, N, O, S, Se and Te) based D-A-D type oligomers: Switch from electropolymerization to structural aspect

摘要

Conjugated polymers are gaining interest because of their potential application in organic electronic devices such as organic solar cells (OSCs), organic field effect transistors (OFETs) and organic light emitting diods (OLEDs). In order to introduce high perform polymers, planarity for high conjugation and absorption in the full solar spectrum are essential criteria. To tune the optical and elecctrochemical properties of polymer, one of the potential approach is introduction of donor-acceptor (D-A) approach where electron rich moieties (Donor) and electron-withdrawing units (Acceptor) are alternatively arranged. Organic heterols such as pyrrole, furan, thiophene, selenophene are extensively used as donor and benzotriazole, benzooxadiazole, benzothiadiazole and benzoselenadiazole are used as conventional acceptor. In the first section of this review the discussion will be coincised into the donor-acceptor-donor (D-A-D) type oligomers and their electropolymerization to develop D-A polymers. The later part of review deals with the advancement in the study, with only D-A-D type oligomers through their structural and interaction property to understand the packing pattern in solid state. Further reports on the application of these oligomers in molecular devices such as FET and sensors are also discussed.