Antibiotic oxidation and fouling control of ceramic microfiltration membrane through effective heterogeneous electro-Fenton process based on nitrogen-doped carbon nanotubes and Cu-Fe bimetallic oxides

Rendering heterogeneous electro-Fenton (hetero-e-Fenton) reactivity is a promising strategy to address the bottlenecks of low-pressure membranes (LPMs), such as the poor ability to remove small-molecular organic pollutants and membrane fouling. However, hetero-e-Fenton catalysis usually suffers from the limitation of the sluggish redox cycle of Fe(III)/Fe(II). Herein, we reported an electrocatalytic ceramic microfiltration membrane functionalized with CuFe2O4 nanoparticles supported by nitrogen-doped carbon nanotubes (NCNTs). The Fe(II) and Cu(I) sites on the CuFe2O4 decomposed the H2O2 generated by NCNTs into ·OH. The electron transfer from the conductive NCNTs support and reducing agent Cu(I) to Fe(III) enabled an effective Fe(II) regeneration. Moreover, the N species in NCNTs enhanced the interfacial interaction between CuFe2O4 nanoparticles and the NCNTs support, expediting the Fe(III)/Fe(II) redox cycle by promoting the interfacial electron transfer. At near-neutral pH, the electrocatalytic membrane delivered excellent tetracycline removal kinetics (0.0134 min−1) and significantly alleviated the organic fouling on the membrane surface and in the pores. The membrane also exhibited good stability, reusability, and permeate water safety. These findings shed new light on the development of next-generation water treatment membranes with catalytic oxidation capabilities.