Recent Advances in Photocatalytic Removal of Per- and Polyfluoroalkyl Substances Using Ceramic-based Materials

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent fluorinated organic contaminants characterized by exceptionally strong Carbon-fluorine (C-F) bonds, which lead to extreme environmental stability, bioaccumulation, and adverse ecological and human health effects. Conventional water treatment technologies such as adsorption, membrane separation, and ion exchange primarily transfer PFAS to secondary phases without molecular destruction, while high-energy destruction processes suffer from significant operational and economic limitations. In this context, photocatalytic degradation has emerged as a promising strategy for PFAS removal owing to its potential to directly cleave C-F bonds under mild conditions. Ceramic-based materials, including metal oxides, nitrides, and sulfides, have played a critical role in the development of photocatalytic PFAS removal technologies due to their high chemical stability, tunable electronic structures, and resistance to harsh reaction environments. Recent advances have demonstrated that defect engineering, doping, heterojunction, and crystal structure modulation can effectively enhance light absorption, charge separation, and reactive species generation, thereby improving PFAS degradation and defluorination efficiencies. Beyond conventional semiconductor ceramics, hybrid systems integrating ceramic photocatalysts with carbonaceous materials, coordination compounds, or porous frameworks have been developed to address mass-transfer limitations through adsorption-assisted pre-concentration and interfacial charge-transfer mechanisms. This review provides a comprehensive overview of recent progress in the photocatalytic removal of PFAS using ceramic-based materials. The discussion covers metal oxide-, nitride-, and sulfide-based photocatalysts, as well as ceramic-based hybrid and framework systems, with a focus on material design strategies, photocatalytic reaction mechanisms, and defluorination pathways.