Molecularly imprinted MOFs-driven carbon nanofiber for sensitive electrochemical detection and targeted electro-Fenton degradation of perfluorooctanoic acid

Abstract

The polyfuoroalkyl substances, especially perfluorooctanoic acid (PFOA), are emerging as harmful environmental micropollutants that are known to globally contaminate water, air, and soil resources. Herein considering the urgent demand for the sensitive detection and effective degradation of PFOA present in water environment, a novel molecular imprinting polymer (MIP) MOFs (Co/Fe)-driven carbon nanofiber (Co/Fe@CNF) electrode has been developed for electrochemical detection and electro-Fenton (EF) degradation of PFOA. MIP was formed by one-pot step by electro-polymerization of the pyrrole in the presence of PFOA template on the Co/Fe@CNF. The MIP has a strong adsorption force on PFOA for the special O–H-π hydrogen bond between PFOA and the imprinting site, helped PFOA to access the surface of electrode. Therefore, the resulting MIP Co/Fe@CNF was able to detect PFOA with a good linear response in the range of 1 × 10-8–9 × 10-5 M, and the limit of detection (LOD) was reached 1.073 × 10-9 M. Moreover, the imprinted cavity on MIP can precisely adsorb PFOA and its intermediates to shorten the transmission distance between free radicals and targets, which enhanced the degradation ability in the EF process, and the targeted degradation efficiency reached 93% with 180 min.