Nanoscale fletching of liquid-like polydimethylsiloxane with single perfluorocarbons enables sustainable oil-repellency.

Oil repellency is essential for enabling self-cleaning, anti-soiling and stain-repelling properties, which has broad application in industries liked textiles, healthcare and electronics. While per-and-polyfluoroalkyl substances (PFAS) exhibits strong oleophobicity, their environmental and health risks have led to prohibition on long-chain PFAS ( ≥ C) and restriction on short-chain PFAS (C, C). However, there are few alternative materials demonstrating comparable oil repellency. Here, we introduce a novel method to fletch polydimethylsiloxane (PDMS) brushes with ultrashort PFAS (singe -CF, the least toxic PFAS), achieving oil repellency similar to short-chain PFAS while drastically reducing the fluorine content. This work highlights that liquid-like molecular design, rather than chain length, can enable sustainable oil repellency, facilitating a smoother transition away from PFAS reliance.