Hamdy Nourhan, Gar Alalm Mohamed, El-Geundi Mohammad, Fuoad Mohram, Samy Mahmoud
Department of Chemical Engineering, Faculty of Engineering, Minia University, Al Minya, Egypt.
Public Works Engineering Department, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt.
Chemosphere. 2025 Sep;384:144506. doi: 10.1016/j.chemosphere.2025.144506. Epub 2025 Jun 5.
In this study, g-CN@BiOBr heterostructure was synthesized at different molar ratios and dispersed into a polyvinylidene fluoride (PVDF) matrix for the photodegradation of atrazine (ATZ, herbicide) under visible light. The investigation of the photocatalytic performance of g-CN@BiOBr/PVDF membrane under different operating parameters has not been extensively studied in the literature. Thus, this study focused on the optimization of the g-CN@BiOBr/PVDF membrane degradation system and deep exploration of the degradation mechanism. Various analyses characterized the as-prepared catalysts and membranes, including XRD, TEM, FTIR, EDX, SEM, XPS, and DRS. The g-CN@BiOBr/PVDF membrane (g-CN@BiOBr at a mole ratio 1:3) showed the highest photocatalytic activity for ATZ removal among the composite membranes. The response surface methodology (RSM) was used to optimize the operating parameters, exhibiting that pH 3, initial ATZ concentration of 0.5 mg/L, and BiOBr mole ratio of 0.75 were the optimum conditions. The contribution of reactive species to the degradation mechanism was investigated using efficient scavengers, confirming the significant roles of •O and h in the reaction process. Furthermore, the as-prepared membrane demonstrated enhanced reusability and stability with an 81 % ATZ removal rate after five cycles. The generated intermediates were identified using liquid chromatography-mass spectroscopy analysis indicating the degradation of ATZ to simpler compounds. The mechanism of the photocatalytic degradation of atrazine by g-CN@BiOBr/PVDF was further proposed. This study proposes a low-cost, efficient, and stable photocatalytic membrane system that can be executed in real applications.
在本研究中，以不同摩尔比合成了g-CN@BiOBr异质结构，并将其分散到聚偏氟乙烯（PVDF）基质中，用于在可见光下光降解莠去津（ATZ，除草剂）。g-CN@BiOBr/PVDF膜在不同操作参数下的光催化性能研究在文献中尚未得到广泛研究。因此，本研究重点在于优化g-CN@BiOBr/PVDF膜降解系统，并深入探索降解机制。通过各种分析对所制备的催化剂和膜进行了表征，包括XRD、TEM、FTIR、EDX、SEM、XPS和DRS。g-CN@BiOBr/PVDF膜（g-CN@BiOBr摩尔比为1:3）在复合膜中对ATZ去除表现出最高的光催化活性。采用响应面法（RSM）优化操作参数，结果表明pH为3、初始ATZ浓度为0.5 mg/L以及BiOBr摩尔比为0.75是最佳条件。使用高效清除剂研究了活性物种对降解机制的贡献，证实了•O和h在反应过程中的重要作用。此外，所制备的膜表现出增强的可重复使用性和稳定性，五个循环后ATZ去除率为81%。使用液相色谱 - 质谱分析鉴定了生成的中间体，表明ATZ降解为更简单的化合物。进一步提出了g-CN@BiOBr/PVDF光催化降解莠去津的机制。本研究提出了一种低成本、高效且稳定且可在实际应用中实施的光催化膜系统。
