Transition metal-Modified Ga2O3 Hierarchical Nanosheets as Efficient Photocatalysts for Degradation of Perfluorooctanoic Acid
More and more attention has been redirected to the per- and polyﬂuorinated alkyl substances (PFASs), particularly perﬂuorooctanoic acid (PFOA), owing to their ecotoxicity and environmental risks. As one of the major emerging and persistent contaminants in the environment, the current treatment processes could not remove PFOA efficiently. The recent advances in heterogeneous photocatalysis have demonstrated high efficiencies in degrading persistent contaminants, which provides an alternative approach for PFOA removal. Notably, Ga2O3-based photocatalysts exhibited great potential for PFOA remediation due to its high oxidizing capability and energy sustainability. Thus, Ga2O3 hierarchical nanosheets modified by a series of transition metals were rationally developed, and applied as heterogeneous photocatalysts for fast and efficient PFOA degradation. Noteworthily, the Indium modified Ga2O3 hierarchical nanosheets achieved prominent PFOA decomposition activity, which can completely degrade 20 mg/L PFOA within 1 hour. The In-Ga2O3 hierarchical composites have dramatically enhanced the degradation kinetics for PFOA, which was 7.8 times higher than that of pristine Ga2O3. With in-depth mechanism investigation, we have demonstrated that In modification can not only can enhance the light-harvesting and suppress the photogenerated carrier recombination, but also favor to improve the adsorption ability to PFOA through the coexistence of monodentate and bidentate/bridging coordination mode. The transition-modification strategy paves a way for fabricating high-performance nanoscale photocatalysts for the removal of PFASs in water.