Photocatalytic degradation of perfluorooctanoic acid (PFOA) by metal organic framework MIL-177-HT: New insights into the role of specific surface area, charge separation and dimensionality

Per- and polyfluoroalkyl substances (PFAS) are known to cause severe adverse health effects. Therefore, their prevalent detection in drinking water calls for rapid development of effective destruction technologies. This paper presents degradation and defluorination of perfluorooctanoic acid (PFOA) by a photocatalytic titanium-based metal–organic framework (MOF), MIL-177-HT. This MOF achieved about 83 % PFOA removal and 32 % defluorination within 24 h, The results suggested that additional characteristics of MOF were also critical for efficient PFOA degradation. A comprehensive comparison of the adsorption capacity and degradation efficiency of different MOFs applied to remove PFOA in the literature indicated that the ligand hydrophobicity, dimensionality of MOFs and corresponding band gaps of MOFs are likely key factors governing the adsorption and the degradation of PFOA. These newly obtained insights markedly advance our knowledge in synthesizing novel MOF structures to degrade PFAS efficiently.