High‐Performance Small Molecule via Tailoring Intermolecular Interactions and its Application in Large‐Area Organic Photovoltaic Modules

Abstract

Solution‐processed organic solar cells are promising owing to their light weight, ease of processability, low cost, flexibility, and large‐area fabrication. Particularly, small‐molecule active materials have been recently developed using straightforward synthesizing methods, exhibiting the least batch‐to‐batch variation in physical and optoelectronic properties and highly reproducible efficiency. A series of 2D‐BDT‐based active materials with various numbers of benzodithiophene (BDT) units and how the number of 2D‐BDT units influences the construction of a well‐defined interconnected structure are reported. The systematically controlled morphology of the 2D‐BDT material helps achieve a high power‐conversion efficiency (PCE) of 8.56% and a high fill factor of 0.73 without the use of additives. The reduced charge recombination and well‐constructed morphology of this material facilitate a PCE of 7.45% in a 77.8 cm 2 rigid module, which is the outstanding performance in large‐area modules.