Interfacial hydrophilicity induced CoAl-LDH/Ti3C2Tx@PVDF Fenton-like catalytic filtration membrane for efficient anti-fouling and water decontamination

Abstract

The catalytic filtration membrane, combining the interfacial hydrophilic effect with PMS based Fenton-like oxidation processes, demonstrates great potential as an advanced solution for alleviating membrane fouling and removing contaminants. Herein, a novel type of hollow fiber CoAl-LDH/Ti₃C₂T_x@PVDF membranes was successfully fabricated. The well-designed hybrid membrane incorporating 0.5 wt% of CoAl-LDH/Ti₃C₂T_x (denoted as M-0.5) as PMS activator exhibited excellent anti-fouling behavior and remarkable TC degradation efficiency. The anchored hetero-structural CoAl-LDH/Ti₃C₂T_x was pivotal in driving the reaction, where the synergistic redox cycles (Ti⁺/Ti²⁺, Ti²⁺/Ti³⁺ and Co²⁺/Co³⁺) facilitated the activation of PMS. Concurrently, the plentiful hydrophilic groups especially -OH of CoAl-LDH/Ti₃C₂T_x endowed M-0.5 with robust interfacial hydrophilicity, extremely boosting interactions among CoAl-LDH/Ti₃C₂T_x, PMS and TC at the surface of M-0.5. Mechanism analysis revealed that the formed ∙OH, SO₄^·-, ·O₂^- and ¹O₂ collectively contributed to the non-selective degradation of TC. Moreover, the M-0.5+PMS system showed exceptional stability in the presence of various environmental interferences and continuous flow device. Ultimately, the degradation pathways and toxicological assessment of TC and its intermediates further substantiated the impressive catalytic oxidation performance of the M-0.5+PMS system. This insightful work cleverly integrates the macro/micro-scale design of membrane structure, promising to unlock novel opportunities for the development of water treatment.