Yue Yao, Wen Teer, He Yunfei, Qu Xuetong, Dou Jibo, Zhong Yuchi, Ding Jiafeng, Zhang Hangjun
School of Engineering, Hangzhou Normal University, Hangzhou 310018, China.
Zhejiang Provincial Key Laboratory of Wetland Intelligent Monitoring and Ecological Restoration, Hangzhou Normal University, Hangzhou 311121, China.
Molecules. 2025 Apr 25;30(9):1917. doi: 10.3390/molecules30091917.
The removal of polychlorinated dibenzo-p-dioxins (PCDDs) via advanced oxidation processes (AOPs) poses a significant challenge due to their high toxicity and chemical stability. In this study, a series of well-dispersed cobalt nanoparticles supported on carbon nitrides (xCoCNs) was synthesized to activate peroxymonosulfate (PMS) for 2,8-dichlorodibenzo-p-dioxin (2,8-DCDD) degradation under visible light. The catalysts prepared were characterized using SEM, XPS, photoluminescence (PL), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). Among them, 2CoCN with an optimal Co content exhibited the highest photocatalytic efficiency, achieving 90.5% degradation of 2,8-DCDD within 160 min under visible light/persulfate oxidation (Vis+PMS+2CoCN system). Compared with other catalysts, 2CoCN exhibited superior optical performance and a narrower bandgap, enabling efficient excitation under visible light (Vis). Notably, all xCoCNs demonstrated pH adaptability, achieving complete degradation of 2,8-DCDD under neutral conditions (pH = 7) without additional acid/alkali adjustment. Through rigorous free radical capture experiments, it was demonstrated that SO, OH and O were the primary reactive oxygen species (ROS) in the Vis+PMS+2CoCN system. The catalyst exhibited excellent reusability, with stable activity retained over five cycles. Based on these findings, degradation pathways and mechanisms of 2,8-DCDD in the 2CoCN+Vis+PMS system were proposed. This study presents an effective approach for PCDD abatement in wastewater treatment applications.
通过高级氧化工艺（AOPs）去除多氯二苯并对二噁英（PCDDs）具有重大挑战，因为它们具有高毒性和化学稳定性。在本研究中，合成了一系列负载在氮化碳上的分散良好的钴纳米颗粒（xCoCNs），以在可见光下活化过一硫酸盐（PMS）用于降解2,8 - 二氯二苯并对二噁英（2,8 - DCDD）。使用扫描电子显微镜（SEM）、X射线光电子能谱（XPS）、光致发光（PL）和紫外 - 可见漫反射光谱（UV - Vis DRS）对制备的催化剂进行了表征。其中，具有最佳钴含量的2CoCN表现出最高的光催化效率，在可见光/过硫酸盐氧化（Vis + PMS + 2CoCN体系）下160分钟内实现了2,8 - DCDD 90.5%的降解。与其他催化剂相比，2CoCN表现出优异的光学性能和更窄的带隙，能够在可见光（Vis）下有效激发。值得注意的是，所有xCoCNs都表现出pH适应性，在中性条件（pH = 7）下无需额外酸碱调节即可实现2,8 - DCDD的完全降解。通过严格的自由基捕获实验表明，SO₄•⁻、•OH和¹O₂是Vis + PMS + 2CoCN体系中的主要活性氧物种（ROS）。该催化剂表现出优异的可重复使用性，在五个循环中保持稳定的活性。基于这些发现，提出了2,8 - DCDD在2CoCN + Vis + PMS体系中的降解途径和机制。本研究为废水处理应用中PCDD的减排提供了一种有效方法。
