Utilizing an electron-deficient thieno[3,4-c]pyrrole-4,6-dione (TPD) unit as a π-bridge to improve the photovoltaic performance of A–π–D–π–A type acceptors

Abstract

The control of intramolecular charge transfer between the fused-ring core and terminal unit by selecting a suitable π-bridge has a strong impact on the photovoltaic performance of A–π–D–π–A type non-fullerene acceptors (NFAs). Here, we used a strong electron-deficient unit, thieno[3,4-c]pyrrole-4,6-dione (TPD), as a π-bridge to synthesize a new NFA, TPD8, which exhibited a low optical bandgap of 1.46 eV. Organic solar cells based on PTQ10:TPD8 gave a power conversion efficiency (PCE) of 10.4% with a relatively high open-circuit voltage (V_OC) of 0.91 V and low energy loss of 0.55 eV. This work proved that electron-deficient units were also a good choice for the construction of high-performance A–π–D–π–A type NFAs.