In this study, graphitic carbon nitride (g-C₃N₄) nanostructures with different molar ratios of ZnO and TiO₂ (i.e. g-C₃N₄/TiO₂, g-C₃N₄/ZnO, and g-C₃N₄/TiO₂-ZnO) were synthesized. The synthesized samples were characterized using field-emission scanning electron microscopy (FE-SEM), x-ray diffraction, Brunauer–Emmett–Teller (BET) analysis, and ultraviolet (UV)–visible diffuse reflectance spectroscopy (UV-vis-DRS) techniques. The FE-SEM images showed the surface morphology of each sample. The UV-vis-DRS results indicated that the bandgap of TiO₂ was reduced by adding g-C₃N₄ and different molar ratios of ZnO. The results obtained from BET analysis confirmed that the surface area of the g-C₃N₄/TiO₂-ZnO (1:10) nanostructure was 97.494 cm² g⁻¹, which was comparatively higher than other nanostructures, and became suitable for photocatalytic activity. The photocatalytic activity of the g-C₃N₄/TiO₂-ZnO nanostructure was performed by photo-degradation of methylene blue (MB) dye under simulated solar light. The results of the photocatalytic activity showed that the synthesized nanostructure had good degradation under UV and visible light irradiation by 94.6% and 62.4%, respectively. Also, the kinetics of the photocatalytic degradation confirmed that degradation of MB dye in the presence of UV light was faster than visible light. Furthermore, a study of the reusability of the nanostructure exhibited good photo-stability and activity after six runs.

中文翻译：

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用于光催化降解亚甲蓝的 g-C3N4/TiO2-ZnO 纳米结构的合成与表征

_{在这项研究中，具有不同ZnO和TiO 2}摩尔比（即gC ₃ N ₄ /TiO ₂、gC ₃ N ₄ /ZnO和gC ₃ N ₄ /TiO ₂ -ZnO ）的石墨碳氮化物（gC ₃ N ₄ ）纳米结构) 被合成。使用场发射扫描电子显微镜 (FE-SEM)、X 射线衍射、Brunauer-Emmett-Teller (BET) 分析和紫外 (UV)-可见漫反射光谱 (UV-vis-DRS) 对合成样品进行表征技巧。FE-SEM 图像显示了每个样品的表面形态。UV-vis-DRS 结果表明 TiO _2的带隙通过添加gC ₃ N ₄和不同摩尔比的ZnO来降低。BET分析结果证实，gC ₃ N ₄ /TiO ₂ -ZnO（1:10）纳米结构的表面积为97.494 cm ² g ^-1，高于其他纳米结构，适合光催化活性. _{gC 3} N ₄ /TiO ₂的光催化活性-ZnO 纳米结构是通过亚甲蓝 (MB) 染料在模拟太阳光下的光降解来实现的。光催化活性结果表明，合成的纳米结构在紫外光和可见光照射下具有良好的降解率，分别为94.6%和62.4%。此外，光催化降解的动力学证实，MB 染料在紫外光存在下的降解比可见光快。此外，纳米结构的可重复使用性研究在六次运行后表现出良好的光稳定性和活性。