Synthesis and self-assembly of diblock copolymers for photovoltaic applications
This dissertation explores the self-assembly of diblock copolymers as a way to control the morphology of photoactive layer in organic solar cells. Heterojunction formation between electron donor and electron acceptor materials needs to be controlled on the nanometer scale to have high power conversion from organic photovoltaic cells. Two approaches were developed to direct the assembly of electron-donors and electron-acceptors into heterojunction structures. The first one involves the synthesis of acid cleavable diblock copolymer to create porous polymer films, which can be used as templates to form well ordered donor-acceptor heterojunctions on the nanometer scale. Here, we demonstrate that nanoporous templates could be prepared under moderate conditions, which do not interfere with photovoltaic device fabrication. The second approach involves the use of conjugated diblock copolymers as the structure directing agents. Incompatible packing of the side chains was investigated to provide microphase segregation in conjugated polymer/fullerene blends. Packing of the materials within the domain has been shown to be a very important parameter for photovoltaic performances.
0490: Organic chemistry
0495: Polymer chemistry