Tailoring the Morphology’s Microevolution for Binary All-Polymer Solar Cells Processed by Aromatic Hydrocarbon Solvent with 16.22% Efficiency

Herein, we report a systematic solvent selection for eco-friendly processed binary all-polymer solar cells (APSCs) with decent power conversion efficiencies (PCEs). Three typical solvents, toluene, o-xylene, and 1,2,4-trimethylbezene, are chosen and compared. The device enabled by o-xylene exhibits the most outstanding PCE of 16.22%, thanks to its favorable morphology, which is to say a well-formed face-on orientation packing motif and a suitable crystallinity and size of phase segregation. Consequently, the solar cell affords sufficient charge generation, as well as efficient and balanced charge transport, which are all positive to pursuing high efficiency. This work offers an understanding of using complete solvent selection as the strategy to realize high-performance devices by sophisticatedly controlling the morphology.