Electronic Metal-Support Interaction Directing the Design of Fe(III)-Based Catalysts for Efficient Advanced Oxidation Processes by Dual Reaction Paths.

Abstract

Persistent organic pollutants (POPs) have a huge impact on human health due to their high toxicity and non-degradability. It is still of great difficulty to develop highly efficient catalysts toward the degradation of POPs. Herein, it is reported that regulating electronic structure of quasi-single atomic ferric iron (Fe(III)) in the VO2 support through the electronic metal-support interaction (EMSI) is a versatile strategy to enhance the catalytic activity. Activated Fe(III) can react with peroxydisulfate (PDS) to produce both radicals and high-valent iron (HVFe) simultaneously for the efficient and fast degradation of POPs. Density functional theory (DFT) calculations prove that the influence of EMSI promotes the electrons on Fe(III) 3d-bond center moving close to the Fermi level, facilitating the charge transfer from Fe(III) to the adsorbate. Through the control experiments, both the radical path by PDS and the HVFe path aroused by the EMSI are confirmed in the POP degradation process. Consequently, the Fe/VO2 catalyst exhibits record-breaking catalytic activity with the k-value as high as 56.7, 43.3µmol s-1 g-1 for p-chlorophenol and 2,4-dichlorophenol degradation, respectively.