Selenium‐Containing π‐Conjugated Polymers for Organic Solar Cells

Abstract Organic solar cell research has attracted scientific and commercial interest in the last decade due to a rapid increase in power conversion efficiencies (PCEs). Today, PCEs in the range of 8–10 % have been obtained using conjugated polymers as electron‐donor materials in combination with fullerene/other acceptors. However, to enable commercial applications, the efficiencies and lifetimes of organic solar cells still need to be improved significantly. In recent years, due to the potential advantages of Se‐containing conjugated materials, namely, lower band gaps, rigidity, and strong Se⋅⋅⋅Se integration, have attracted surprising attention for use in organic solar cells. In this review, we focus on the synthesis and applications of Se‐containing conjugated polymers for organic solar cells and throughout compare them with S‐ and O‐containing analogues where applicable. The relationships between the chemical structures and properties, such as absorptions, energy levels, mobilities, and photovoltaic behavior, are also discussed.