Removable Additive Assists Blade‐Coated Large‐Area Organic Solar Cell Modules Fabricated with Non‐Halogenated Solvents Achieving Efficiency Over 16%

Abstract The critical step in commercializing organic solar cells (OSCs) involves achieving high‐performance modules through environmentally friendly solvents. The incorporation of solid additives, recognized as an effective method for modulating the morphology of active layers through layer‐by‐layer (LBL) deposition, plays a significant role. Here, a novel volatile solid additive is introduced individually into the non‐halogenated solution of donor PM6 as a morphology‐modulating agent. The additive induces conformational and crystalline orientation change of PM6, resulting in enhanced and balanced charge transport in the active layer. With a focus on exciton dynamics, the optimized active layer inhibits the formation of low‐energy triplet states. It facilitates strong reverse hole transfer processes, leading to more efficient exciton dissociation. The final small‐area LBL blade‐coated OSCs fabricated under ambient conditions achieve a power conversion efficiency (PCE) of 18.42%. Furthermore, a large‐area module with an area of 28.82 cm 2 is manufactured, achieving a PCE of 16.04% with a high geometric fill factor of 93.8%. This highlights the effective modulation of the active layer through the use of solid additives and provides a successful strategy for fabricating high‐performance OSC modules with non‐halogenated solvents.