Catalytic nanofiber composite membrane with bimetal heterojunction enabling dynamic photo-Fenton degradation for efficient and multitasking pollutants removal

With the increasing complexity of wastewater, the development of catalytic membranes featuring heterojunctions of catalysts combined with advanced oxidation techniques has become a promising approach for wastewater treatment. This study prepared a heterostructured bimetal-based polyetherimide (PEI) catalytic membrane (HBPCM) via electrospinning and in-situ growth. The Z-type heterojunction of FeOOH and ZnO enhanced electron mobility, reducing photoluminescence intensity, Nyquist arc radius, and increasing photocurrent response, thereby improving redox and photocatalytic performance. Integrating photo-Fenton and membrane processes facilitated dynamic catalytic reaction, enhancing pollutant degradation through improved mass transfer. The photo-Fenton degradation of HBPCM for methyl orange (MO), orange G (OG), methylene blue (MB) and phenol (phOH) in static experiments reached 96.6 %, 87.5 %, 92.3 % and 95.7 % within 10 min, which were much higher than that of iron-based PEI catalytic membrane (IPCM) or zinc-based PEI catalytic membrane (ZPCM) in single photocatalysis or Fenton catalysis process. In dynamic experiments, photo-Fenton efficiency of HBPCM for MO, OG, MB, and phOH in 10 min was 8.55, 8.25, 6.86, and 2.69 times higher than in static conditions. Furthermore, loading FeOOH/ZnO conferred superhydrophilicity to the membrane, enhancing oil-water separation performance. Combining membrane technology with photo-Fenton catalysis offers an effective approach for treating complex wastewater.