Abstract: The applicability of the conventional Fenton reaction is limited due to several factors, including the high cost and slow redox cycle of Fe³⁺/Fe²⁺, the requirement for harsh acidic conditions, and the insufficient presence of hydroxyl radicals for the ring-opening reaction. The combination of photocatalysis and Fenton technology to create a photocatalysis-in-situ-self-Fenton (PISF) system is a viable approach for addressing the inherent limitations of conventional Fenton reactions. Herein, a multifunctional PISF system, MIL-88A(Fe)/Ti₃C₂ MXene/resorcinol-formaldehyde (MIL-88A(Fe)/Ti₃C₂/RF, MTR) Z-scheme heterojunction, was designed and constructed for degradating organics and inactivating bacteria. With the assistance of Ti₃C₂, the degradation rate of TC by MTR catalyst was 4.8 times that of MIL-88A(Fe)/RF catalyst under visible light irradiation. Meanwhile, good degradation performance was maintained after 5 cycling tests. The remarkable TC removal efficiency (97.4 %) and durability were attributed to the synergistic effect of the photocatalytic reaction and Fenton reaction. The photoinduced holes (h⁺) assist hydroxyl radicals (•OH) generated by the Fenton reaction for deeply mineralizing TC. The degradation intermediates, potential degradation pathways, and intermediates toxicity were comprehensively investigated to gain a deeper understanding of the catalytic process. Moreover, under visible light irradiation, the MTR killed 97.8 % of E. coli and 94.9 % of S. aureus within 120 min, demonstrating good antibacterial activity. This work provides a novel strategy to design PISF catalysts for environmental remediation.

Key words: Multifunctional photocatalysts, MXene, Z-scheme heterojunction, Photocatalysis-in-situ-self-Fenton system