A high dielectric constant non-fullerene acceptor for efficient bulk-heterojunction organic solar cells

Abstract

A non-fullerene acceptor with a high relative dielectric constant (<italic>ε</italic>_r) over 9 is developed. It offers an efficiency of 8.5%, which is the best result for organic solar cells employing high <italic>ε</italic>_r materials. Further research should focus on morphology optimization to make high <italic>ε</italic>_r practically useful in devices.