Non-fullerene acceptors for organic solar cells

Solar cells based on organic semiconductor molecules are a promising alternative to conventional silicon photocells owing to their low cost, simple production, and good mechanical properties. Effective organic photocells are based on a heterojunction using an active layer consisting of two different organic semiconductors, one of which is an electron donor, while the other is an acceptor. Progress in organic photovoltaics is related to the development of new donor materials, while fullerene derivatives are commonly used as acceptors. The advantages and disadvantages of fullerene compounds for organic solar cells are discussed in this review, the principles of their operation are briefly considered, and the most successful new non-fullerene acceptors are described. The application of latter acceptors has made it possible to fabricate organic solar cells with an efficiency of about 2–4%.