Hydrophobic SERS substrate for PFOA sensing and cooperative adsorption.

The widespread use of perfluorinated organic compounds (PFOA) has posed significant threats to ecosystems and biological health. This study investigates a fluorinated metal-organic framework (F-MOF) for highly sensitive SERS detection and efficient adsorption of PFOA in aqueous environments. Au@MIL-4F, synthesized via a mild thermochemical method using tetrafluoroterephthalic acid and iron (Ⅲ), exhibits exceptional selectivity and sensitivity toward PFOA, achieving a broad detection range with a remarkably low detection limit of 38 pM. The SERS sensor demonstrates excellent reproducibility and stability. Furthermore, adsorption kinetics and thermodynamic studies reveal a maximum adsorption capacity of 254.25 mg/g for PFOA on Au@MIL-4F. The adsorption mechanism, elucidated through spectroscopic and structural analyses, provides critical theoretical insights for developing dual-functional systems that integrate detection and adsorption capabilities. This work not only advances material design for environmental remediation but also offers a practical strategy to address PFOA contamination with precision and sustainability.