Spirobifluorene-Cored Tetrameric Acceptors with a Perpendicular Interlocking Toroidal Topology for Efficient and Stable Organic Solar Cells
Small-molecule fused-ring electron acceptors (FREAs) have greatly advanced the efficiency of organic solar cells (OSCs), yet their long-term operational stability remains a critical hurdle for practical applications. Covalently linking FREA units into oligomers offers a promising strategy to address this issue, but t...