Recent progress on photoactive heterogeneous photocatalysts for the degradation of Per-and Polyfluoroalkyl Substances (PFAS): Mechanisms, DFT calculations, limitations, and future prospects

Abstract

Poly-and perfluoroalkyl substances (PFAS) are manmade chemicals, which are resistant to conventional degradation, bioaccumulate, and possess a significant health risk to mankind. Due to their adverse effects on human health, the removal of PFAS with different mechanisms such as physical, chemical, and biological methods attract considerable attention in recent years. Among them, the photochemical degradation method with photocatalysis system is considered as an effective technology in which the renewable light resource can be utilized to achieve the degradation process. This review summarizes mainly heterogenous photoactive nanomaterials such as metal oxides, metal sulfides, oxyhalides, metal organic frameworks (MOFs) and MOFs-derived photocatalysts, and other related materials for effective removal of PFAS. Moreover, the photoactive nanomaterials design and synthesis, catalytic performance evaluations and efficiency enhancement strategies, density functional theory (DFT) calculations, and detail photodegradation mechanisms for PFAS are also included and critically analyzed. Besides, challenges, limitations, and future prospects in the remediation of wastewater for PFAS are also included. We believe that this review will provide innovative prospective and insight to design effective strategies for environmental remediation.