甲基橙嵌入的g-C₃N₄用于光催化降解四环素和产氢

Methyl Orange-Embedded g-C₃N₄ for Photocatalytic Degradation of Tetracycline and Hydrogen Production

摘要: 采用二氰二胺与甲基橙(MO)为前驱体，通过热共聚工艺制备出甲基橙嵌入的石墨相氮化碳(CN-MO)，同时对甲基橙的含量进行了调控。通过X射线衍射、红外光谱、X射线光电子能谱、紫外–可见吸收光谱及荧光光谱对材料进行了表征。结果表明：相较于g-C₃N₄ (CN)，CN-MO₁₅的可见光响应范围变宽，同时光生载流子分离效率显著增强。光催化分解水产氢结果表明，经甲基橙嵌入的CN展现出优异的析氢性能，其中CN-MO₁₅在可见光照射条件下的产氢速率达到858.14 μmol·g⁻¹·h⁻¹，为CN的10.96倍。光催化降解实验表明，该催化剂对四环素的降解动力学常数为0.01006 min⁻¹，降解速率是CN的2.53倍，该研究为高效可见光催化剂开发提供了新途径。

Abstract: A methyl orange-embedded graphitic carbon nitride (CN-MO) was synthesized via thermal copolycondensation using dicyandiamide and methyl orange (MO) as precursors, with the MO content systematically varied. The materials were characterized by XRD, FTIR, UV-Vis, XPS and PL. The results indicated that compared to pristine g-C₃N₄ (CN), CN-MO₁₅ exhibited a broadened visible-light absorption range and a notably enhanced charge separation efficiency. Photocatalytic water splitting experiments demonstrated the superior hydrogen evolution performance of the MO-embedded catalysts. Specifically, CN-MO₁₅ achieved a hydrogen evolution rate of 858.14 μmol·g⁻¹·h⁻¹ under visible light irradiation, which is 10.96 times higher than that of CN. Furthermore, the apparent rate constant for tetracycline degradation over CN-MO₁₅ reached 0.01006 min⁻¹ in photocatalytic degradation tests, representing a 2.53-fold enhancement over CN. This study provides a novel strategy for developing highly efficient visible-light-responsive photocatalysts.