Considering the costs and complexity constraints of the large-scale commercial application of organic solar cells (OSCs), developing efficient as-cast devices is imperative. Recently, the research group led by Professor Zhang Maojie from the National Engineering Research Center for Colloidal Materials has made a significant breakthrough in this field. The team has successfully synthesized novel non-fullerene acceptors (NFAs) by vinyl-functionalizing linear alkyl chains to regulate molecular stacking and optimize the double-fibril network morphology. Consequently, the team has achieved highly efficient and stable as-cast devices. Their study, “Vinyl-Functionalized Linear Alkyl Chains in Non-fullerene Acceptors Enable 19.2% Efficiency and Stable As-Cast Organic Solar Cells”, was published in Angewandte Chemie International Edition. Professor Zhang Maojie is the corresponding author, and PhD candidate Han Chenyu is the first author. Shandong University is the primary institution affiliated with this work.

To achieve the desired morphology through single-step processing, Prof. Zhang’s team employed an alkyl linearization strategy to develop novel NFAs, namely BTP-N6 and BTP-V6. Upon alkyl linearization, the steric hindrance of the inner alkyl chain diminishes, and the dihedral angles of the molecule skeleton promote tightly oriented molecular stacking. Moreover, BTP-V6, featuring vinyl-functionalized linear chains, manifests additional interaction sites, which led to enhancedπ–πstacking and refined dual-fibril network morphology during the rapid film-formation process. As a result, the D18:BTP-V6-based as-cast device achieved a record-breaking PCE of 19.2% and a fill factor (FF) of 80.7%. Additionally, the layer-by-layer (LBL) structured device attained a champion PCE of 20.1%, which ranks as one of the highest values of binary OSCs. Moreover, D18:BTP-V6-based devices demonstrated exceptional thermal and shelf stability.

This work proposes an innovative and straightforward approach for constructing efficient and facilely processed OSCs, which simplifies manufacturing and reduces production costs for future commercial applications.

This work was supported by the Shandong Provincial Natural Science Foundation, the Taishan Scholar Program of Shandong Province, the Distinguished Young and Middle-Aged Scholars Program of Shandong University, and the Cheeloo Young Scholars Program of Shandong University. The Structural Composition and Property Measurement Platform at Shandong University provided critical support for structural characterization.