Karaca Melike, Eroğlu Zafer, Açışlı Özkan, Metin Önder, Karaca Semra
Department of Chemistry, Faculty of Science, Atatürk University, 25240 Erzurum, Turkey.
Department of Chemistry, College of Sciences, Koç University, Sarıyer, 34450 Istanbul, Turkey.
ACS Omega. 2023 Jul 12;8(29):26597-26609. doi: 10.1021/acsomega.3c03532. eCollection 2023 Jul 25.
N-doped carbon quantum dots (N-CQDs) derived from the L. plant were incorporated into TiO via a facile hydrothermal method. As-prepared materials were characterized and used in the photocatalytic tetracycline (TC) degradation under UVA light irradiation by examining several operational parameters involving the N-CQDs amount, initial TC concentration, pH, and photocatalytic reaction time. XRD analysis revealed the conversion of the rutile phase to the anatase phase after the incorporation of N-CQDs into the TiO structure. The results revealed that the N-CQDs/TiO photocatalysts demonstrated the highest efficiency in TC degradation compared to other processes of adsorption, photolysis (UVA), and photocatalysis with TiO (TiO/UVA). Under optimized conditions, 10 mg/L TC at pH 5.15 with 0.2 g/L N-CQDs/TiO catalyst showed 97.7% photocatalytic degradation for 120 min under UVA irradiation. The formation of an S-scheme heterojunction between N-CQDs and TiO provided enhanced charge separation and strong redox capability, causing significant improvement in the photocatalytic performance of N-CQDs/TiO. Trapping experiments showed that O and h are the predominant reactive species for the TC elimination in an aqueous solution.
通过简便的水热法将源自植物乳杆菌的氮掺杂碳量子点（N-CQDs）掺入二氧化钛（TiO₂）中。对所制备的材料进行了表征，并通过考察包括N-CQDs用量、四环素（TC）初始浓度、pH值和光催化反应时间等几个操作参数，将其用于紫外光A（UVA）照射下光催化降解四环素（TC）。X射线衍射（XRD）分析表明，将N-CQDs掺入TiO₂结构后，金红石相转变为锐钛矿相。结果表明，与吸附、光解（UVA）和TiO₂光催化（TiO₂/UVA）等其他过程相比，N-CQDs/TiO₂光催化剂在TC降解方面表现出最高的效率。在优化条件下，在pH为5.15、含有0.2 g/L N-CQDs/TiO₂催化剂的情况下，10 mg/L的TC在UVA照射下120分钟内的光催化降解率为97.7%。N-CQDs与TiO₂之间形成的S型异质结提供了增强的电荷分离和强大的氧化还原能力，从而显著提高了N-CQDs/TiO₂的光催化性能。捕获实验表明，超氧阴离子（O₂⁻）和空穴（h⁺）是水溶液中TC去除的主要活性物种。
