School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, China; College of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
College of Environmental Science and Technology, Tongji University, Shanghai, 200092, China.
J Environ Manage. 2024 Nov;370:122580. doi: 10.1016/j.jenvman.2024.122580. Epub 2024 Sep 19.
Photocatalysis-self-Fenton combining photocatalytic production of HO with Fenton reaction has been a hotspot, but the pH limitation and iron sludge production problems remain unsolved. Herein, we proposed a self-fenton system based on N-doped carbon dots modified ZnInS (NCDs@ZnInS) composites that exhibits effective degradation of antibiotics under neutral pH using low amounts of Fe. The decoration of ZnInS with NCDs significantly increased the surface area, visible light absorption, charge transfer ability and oxygen adsorption ability. NCDs@ZnInS composites exhibited a high HO production rate (1528 μM g•h) under visible light, which was 1.9 and 5.3 times higher than ZnInS and NCDs, respectively. Meanwhile, the Fe/NCDs@ZnInS system with a low concentration of Fe(1 mg/L) could remove over 95% levofloxacin and oxytetracycline within 30 min. Interestingly, the highest degradation efficiency occurred under neutral pH. Quenching experiments and analytical measurements indicated that the high catalytic performance under pH = 7 with low amounts of Fe stemmed from the higher amount of inner-generate HO under neutral pH and easy regeneration of Fe by photoinduced electrons for high •OH yields. Additionally, the Fe/NCDs@ZnInS system exhibited high degradation performance under different water matrix and ultrahigh degradation efficiency towards levofloxacin under real sunlight irradiation. The work shows the prospects of photocatalysis-self-Fenton systems for overcoming the pH limitation and the difficulty of iron sludge separation in the purification of effluents.
光催化自芬顿结合光催化产生 HO 与芬顿反应一直是一个热点，但 pH 限制和铁污泥产生问题仍未得到解决。在此，我们提出了一种基于氮掺杂碳点修饰的 ZnInS（NCDs@ZnInS）复合材料的自芬顿体系，该体系在中性 pH 下使用少量 Fe 就能有效地降解抗生素。ZnInS 上 NCDs 的修饰显著提高了比表面积、可见光吸收、电荷转移能力和氧气吸附能力。NCDs@ZnInS 复合材料在可见光下表现出高的 HO 生成速率（1528 μM·g·h），分别是 ZnInS 和 NCDs 的 1.9 倍和 5.3 倍。同时，Fe/NCDs@ZnInS 体系中 Fe 的浓度较低（1 mg/L），在 30 min 内可以去除超过 95%的左氧氟沙星和土霉素。有趣的是，在中性 pH 下，降解效率最高。猝灭实验和分析测量表明，在 pH = 7 下，Fe 用量低且具有高催化性能，这是由于在中性 pH 下内生成的 HO 数量较高，以及光诱导电子容易再生 Fe 以获得高的 •OH 产量。此外，Fe/NCDs@ZnInS 体系在不同水基质下表现出高的降解性能，在实际太阳光照射下对左氧氟沙星具有超高的降解效率。这项工作展示了光催化自芬顿系统在克服 pH 限制和废水净化中铁污泥分离困难方面的前景。
