Advanced Functional Polymers for Increasing the Stability of Organic Photovoltaics

The development of new advanced polymers for improving the stability of OPV is reviewed. Two main degradation pathways for the OPV active layer are identified: photochemically initiated reactions primarily starting in the side chains and morphological changes that degrade the important nanostructure. Chemical units can be introduced that impart an increased stability. Similarly, the morphological degradation of the optimal nanostructure can be reduced. Active polymers and blends with acceptor material are used to create nanoparticle links with controlled size. Most of these advanced polymers and processing methods have only been utilized in small-scale devices prepared by standard techniques such as spin coating, but a few cases of roll-to-roll processed solar cells with heat-cleaved side chains are discussed.