Photocatalytic Degradation of Perfluorooctanoic Acid

Perfluorooctanoic acid (PFOA) is an emerging persistent organic pollutant receiving increasing attention due to its global occurrence and resistance to most conventional degradation methods. Some special techniques such as ultrasonication, aqueous electron reduction, persulfate photolysis, and phosphotungstic-acid photocatalysis have been developed to decompose PFOA. However, these methods are not satisfactory due to their harsh reaction conditions or/and high energy consumption. Heterogeneous photocatalysis based on TiO2, an effective, mild method for the treatment of most waters contaminated with organic compounds, is ineffective in degrading PFOA. Recently, we found other semiconductor materials possess higher PFOA degradation activities than TiO2, such as β-Ga2O3 and In2O3. This paper provides an overview of some recent advances in the photocatalytic degradation of PFOA: (1) mechanism for photocatalytic degradation of PFOA by In2O3, (2) the photocatalytic performance of different In2O3 nanostructures, (3) photocatalytic degradation of PFOA by β-Ga2O3 nanomaterials, (4) potential applications in wastewater treatment.