Constraining the\nExcessive Aggregation of Non-Fullerene\nAcceptor Molecules Enables Organic Solar Modules with the Efficiency\n>16%

Translating high-performance organic solar cell (OSC)\nmaterials\nfrom spin-coating to scalable processing is imperative for advancing\norganic photovoltaics. For bridging the gap between laboratory research\nand industrialization, it is essential to understand the structural\nformation dynamics within the photoactive layer during printing processes.\nIn this study, two typical printing-compatible solvents in the doctor-blading\nprocess are employed to explore the intricate mechanisms governing\nthe thin-film formation in the state-of-the-art photovoltaic system\nPM6:L8-BO. Our findings highlight the synergistic influence of both\nthe donor polymer PM6 and the solvent with a high boiling point on\nthe structural dynamics of L8-BO within the photoactive layer, significantly\ninfluencing its morphological properties. The optimized processing\nstrategy effectively suppresses the excessive aggregation of L8-BO\nduring the slow drying process in doctor-blading, enhancing thin-film\ncrystallization with preferential molecular orientation. These improvements\nfacilitate more efficient charge transport, suppress thin-film defects\nand charge recombination, and finally enhance the upscaling potential.\nConsequently, the optimized PM6:L8-BO OSCs demonstrate power conversion\nefficiencies of 18.42% in small-area devices (0.064 cm<sup>2</sup>) and 16.02% in modules (11.70 cm<sup>2</sup>), respectively. Overall,\nthis research provides valuable insights into the interplay among\nthin-film formation kinetics, structure dynamics, and device performance\nin scalable processing.