Mil-101(Fe)@Zn/Co-Zifs Metal–Organic Frameworks are Effective Photo-Fenton Catalysts for Rhb Removal

Abstract

Treating dye-contaminated wastewater using the visible light–driven photo-Fenton reaction is beneficial to environmental remediation. This paper reports the synthesis of a novel, highly effective photo-Fenton catalyst, the MIL-101(Fe)@Zn/Co-ZIFs composite, by a facile internal-growth method. The composite, which had an MOF-in-MOF structure, activated H2O2 to decompose RhB, a polluting-dye model, under visible-light illumination. Via the Z-scheme, the transfer of the electron–hole pair was synergistically accelerated by the reaction centers of the composite (the MIL-101(Fe) shell and Zn/Co-ZIFs core), which enhanced H2O2 activation. The generated •OH, •O2−, and 1O2 effectively decomposed RhB. The composite’s catalytic performance was significantly enhanced by the electronic hybridization of its Fe3+, Co2+, and Zn2+ metal centers. Thus, the composite demonstrated a remarkable capability to remove RhB. This study provides a novel method to construct an MIL-101(Fe)@Zn/Co-ZIFs catalyst with dual reaction centers that enhance the transfer of electron–hole pairs. Our findings inspire the application of MOF-based photo-Fenton catalysts to wastewater treatment and environmental remediation.

Keywords: MOF-in-MOF, Z-Scheme, photo-Fenton, environmental remediation