【摘要】 以商用TiO₂颗粒和三聚氰胺为原料,采用高温煅烧法制备g-C₃N₄/TiO₂复合光催化材料。利用X射线衍射仪（XRD）、扫描电镜（SEM）、透射电镜（TEM）、低温氮气物理吸附和紫外-可见漫反射光谱仪（UV-vis）对g-C₃N₄/TiO₂的进行表征,并研究在可见光条件下g-C₃N₄/TiO₂对溶液中磺胺二甲基嘧啶（Sulfamethazine,SMT）的光催化降解效果。结果表明:TiO₂颗粒附着在层状结构g-C₃N₄/表面,形成具有孔隙结构和更大比表面积的g-C₃N₄/TiO₂,有利于污染物的吸附。g-C₃N₄/TiO₂的光吸收带边移动到430 nm,具有可见光响应。在可见光照射下,当g-C₃N₄/TiO₂投加量为0.2 g/L时,初始浓度为0.5 mg/L的SMT在3 h内去除率可达98.8%。在相同条件下,g-C₃N₄和TiO₂只能分别去除57.8%和9.7%的SMT。活性物质掩蔽实验表明g-C₃N₄/TiO₂光催化降解SMT过程中,超氧自由基（·O2-）和光生空穴（h+）在降解SMT时起主要作用。更多还原

【Abstract】 Graphitic carbon nitride/titanium dioxide（ g-C₃N₄/TiO₂） hybrid photocatalysts were synthesized by heating mixtures of commercial TiO₂ particles and melamine. The g-C₃N₄/TiO₂ samples were characterized by X-ray diffraction（ XRD）,scanning electron microscopy（ SEM）,transmission electron microscopy（ TEM）,low temperature nitrogen adsorption and UV-visible diffused reflectance spectroscopy（ UV-vis DRS）. The photocatalytic degradation of sulfamethazine（ SMT） was investigated by using g-C₃N₄/TiO₂ under visible light. The results show that TiO₂ is distribute on layered structure of g-C₃N₄,and form g-C₃N₄/TiO₂ with pore structure and larger specific surface areas. The g-C₃N₄/TiO₂ has visible light response with absorption edge of 430 nm. When the dosage of g-C₃N₄/TiO₂ is 0. 2 g/L,about 98. 8% of SMT in solution is removed in 3 h with an initial concentration of 0. 5 mg/L under visiblelight,much higher than g-C₃N₄（ 57. 8%） and TiO₂（ 9. 7%）. The results of active species trapping experiments reveal that the holes（ h+） and superoxide radical（ ·O2-） make a major contribution in photocatalytic degradation of SMT by g-C₃N₄/TiO₂.更多还原