High face-on ratio isoindigo copolymers with extended nano-fibrillar networks in fullerene-based thick (>300 nm) photovoltaics achieving a high efficiency of 10.7%

In addition to the thick active layer (>300 nm), the extended nano-fibrillar network and a high face-on ratio of isoindigo copolymers in the nano-fibrillar network raise the short-circuit current density up to 22 mA cm⁻² and efficiency near 10.7%.