Synergistic MXene-bridged g-C3N4/MIL-101(Fe) ternary heterostructure for enhanced visible-light-driven photo-Fenton degradation of pollutants

Ternary g-C 3 N 4 /Ti 3 C 2 T x /MIL-101(Fe) photocatalyst was constructed via in situ assembly. • Ti 3 C 2 T x promotes interfacial charge separation and accelerates electron transfer. • Rapid in situ H 2 O 2 generation enables an oxidant-free visible-light photo-Fenton process. • CTF achieves efficient, broad-spectrum degradation of dyes and PPCPs. Visible-light photo-Fenton oxidation represents a promising strategy for removing dyes and pharmaceuticals/personal care products (PPCPs), which are persistent water contaminants. However, its broader application is constrained by challenges such as inefficient charge separation and dependence on externally added hydrogen peroxide (H 2 O 2 ). In this study, a ternary g-C 3 N 4 /Ti 3 C 2 T x /MIL-101(Fe) photocatalyst was synthesized via the in-situ growth of MIL-101(Fe) on g-C 3 N 4 /Ti 3 C 2 T x , enabling efficient visible-light-driven, zero-external H 2 O 2 -added photo-Fenton degradation of organic pollutants. The hybrid system exhibits significantly enhanced oxygen activation and interfacial electron-transfer capability, with in situ H 2 O 2 generation rates about three times higher than those of pristine g-C 3 N 4 . Under visible-light irradiation, the composite continuously produces reactive oxygen species ( ∙ O 2 - , and ∙ OH) at substantially higher levels than g-C 3 N 4 and g-C 3 N 4 /MIL-101(Fe), indicating promoted charge separation and faster interfacial electron transfer. As a result, the catalyst enables broad-spectrum pollutant removal within 60 min, achieving degradation efficiencies of 99.78% (methylene blue), 99.49% (rhodamine B), 88.27% (tribromophenol), 61.50% (doxycycline hydrochloride), and 78.98% (levofloxacin). Overall, rapid in situ H 2 O 2 formation, coupled with efficient ROS generation, enables high-performance pollutant degradation without the need for external oxidant dosing, providing a green strategy for degrading dyes and PPCPs under visible light. Download: Download high-res image (174KB) Download: Download full-size image A ternary g-C 3 N 4 /Ti 3 C 2 T x /MIL-101(Fe) photocatalyst enables visible-light-driven, oxidant-free photo-Fenton degradation of dyes and PPCPs through MXene-promoted charge separation and rapid in situ H 2 O 2 generation. The self-generated H 2 O 2 activates Fe 3+ /Fe 2+ cycling to continuously produce h + , ∙O 2 - , and ∙OH, achieving efficient pollutant mineralization.