A novel copper oxide/titanium membrane integrated with peroxymonosulfate activation for efficient phenolic pollutants...

Herein, a novel CuO catalyst functionalized Ti-based catalytic membrane (FCTM) was prepared via the regulated electro-deposition technique followed with low-temperature calcination. The morphology of CuO catalyst and oxygen vacancy (O_V) content can be controlled by adjusting the preparation conditions, under optimal condition (400 °C, electrolyte as sulfuric acid), the fern-shaped CuO catalyst was formed and the O_V content was up to its highest level. Under the optimal treatment condition, the 4-chlorophenol (4-CP) removal of the membrane filtration combined with peroxymonosulfate (PMS) activation (MFPA) process was up to 98.2% (TOC removal of 88.2%). Mechanism studying showed that the enhanced performance in this system was mainly due to the increased production of singlet oxygen (¹O₂) via the co-effect of fern-shaped CuO (increased specific surface area) and its fine-tuned O_V (precursor of ¹O₂), which not only synergistically enhanced adsorption ability but also offered more active sites for PMS activation. Theoretical calculations showed that the O_V-rich CuO displayed high adsorption energy for PMS molecule, leading to the change in OO and OH bond (tend to ¹O₂) of the PMS molecule. Finally, the possible three degradation pathways of 4-CP were formed by the electrophilic attacking of ¹O₂.