Synthesis and Process-Dependent Film Structure of All-Conjugated Copolymers for Organic Photovoltaics

Donor-acceptor all-conjugated block copolymers can be used to build organic photovoltaics (OPVs) with improved interfacial structure, broader light absorption, and enhanced performance. The past decade has seen significant progress in the synthesis and structure analysis of all-conjugated block copolymers. One system in particular - Poly(3 alkylthiophene) b poly(9',9'-dioctylfluorene) (P3AT-b-PF) has served as a model system for developing new synthetic techniques and analyzing the microstructure in thin films, in the melt, and in the solutions. This article reviews work with P3AT b PF block copolymers, emphasizing both material synthesis and analysis of crystallinity, micro-phase segregation in films, and aggregation in solutions. This overview demonstrates significant advances in the preparation and characterization of all-conjugated block copolymers and emphasizes remaining challenges in the application of all-conjugated block copolymers for OPVs.