One plastic improves the shortages of photovoltaic and mechanical properties in flexible semitransparent organic photovoltaics

Semitransparency and flexibility are the most attractive properties of organic solar cells (OSCs) for application development. However, the enhancement of visible light transparency by reducing the donor content must result in flexibility loss. One plastic polymer PAEN simultaneously acting as a mechanical additive, absorbance compensator, and morphological modifier is added in the donor-poor active layer. Its good miscibility with L8-BO not only forms a stress dissipation network in the brittle small molecular matrix, but also facilitates charge transport by enlarging the D18 and L8-BO phase separation with better donor crystallinity. Consequently, the PAEN-contained FST-OSC demonstrates an improved LUE of 2.8% with good mechanical durability.