Non-Fullerene Acceptor Order Ranges in an Interpenetrated 3-D Texture Derives Efficient Channel II Process

Abstract

To achieve efficient non-fullerene polymer solar cells (NF-PSCs), three trialkylsilyl substituted benzodithiophene-based polymer donors (PJ1, PJ2, and PJ3) were synthesized with fine-tuning the highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) and optical absorption. Using the polymer series paired with absorption-complementary small molecular acceptors (SMAs), namely, m-ITIC, IDIC, and AIDIC, we systematically studied the performance of a 3×3 matrix of NF-PSCs. An increasing open-circuit voltage with deepening HOMOs of the polymer donors, the enhanced short-circuit current (JSC) and fill factor (FF) were ascribed to the well-intermixed blend morphology containing enhanced SMAs order ranges with mixed face-on and edge-on orientations, that so-called 3-D texture. Such an optimal microstructure is best exemplified in PJ2:IDIC combination, affording a highest efficiency of 12.01% with simultaneously high JSC of 16.98 mA cm-2 and FF of 75.27%.