We examine the photocatalytic activity (PCA) of ZnO/graphitic carbon nitride g-C₃N₄ (g-CN) composite material for methylene blue (MB) degradation under visible-light irradiation (VLI). The polymeric g-CN materials were fabricated by the pyrolysis of urea and thiourea. More importantly, ZnO/g-CN nanostructured composites were fabricated by adding the different mounts (60, 65, 70, and 75 wt.%) of g-CN into ZnO via the simple hydrothermal process. Among fabricated composites, the 75% ZnO/g-CN nanocomposites displayed a superior PCA for MB degradation, which were ~three-fold an enhancement over the pure ZnO nanoparticles. The fabricated materials have been evaluated by X-ray diffraction (XRD), UV-Vis, Fourier transform infrared (FT-IR) spectroscopy, and electron microscopy. More importantly, the photodegradation of MB could get 98% in ZnO/g-CN could be credited to efficient separation of photo-induced charge carriers between ZnO and g-CN. Also, the recycling efficiency of the as-prepared composites was studied for multiple cycles, which shows that the photocatalysts are stable and suitable to carry out photocatalytic degradation in the logistic mode. Additionally, the probable photocatalytic mechanism has also discussed. The synthetic procedure of ZnO/g-CN based materials can be used in numerous fields such as environmental and in energy storage applications.

中文翻译：

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高效ZnO / g-C3N4纳米复合光催化剂的合成与表征。

我们研究了ZnO /石墨氮化碳gC ₃ N ₄的光催化活性（PCA）（g-CN）复合材料，用于在可见光照射（VLI）下降解亚甲基蓝（MB）。聚合g-CN材料是通过尿素和硫脲的热解制备的。更重要的是，ZnO / g-CN纳米结构复合材料是通过简单的水热工艺将不同含量的g-CN（60、65、70和75 wt。％）添加到ZnO中而制成的。在制成的复合材料中，75％的ZnO / g-CN纳米复合材料对MB降解显示出优异的PCA，比纯ZnO纳米颗粒增强了约三倍。通过X射线衍射（XRD），UV-Vis，傅立叶变换红外（FT-IR）光谱和电子显微镜对制造的材料进行了评估。更重要的是，ZnO / g-CN中MB的光降解可达到98％，这可归因于ZnO和g-CN之间光诱导电荷载流子的有效分离。此外，对制备的复合材料的循环效率进行了多次循环研究，结果表明，光催化剂是稳定的，适合以逻辑模式进行光催化降解。另外，还讨论了可能的光催化机理。ZnO / g-CN基材料的合成程序可用于许多领域，例如环境和储能应用。还讨论了可能的光催化机理。ZnO / g-CN基材料的合成程序可用于许多领域，例如环境和储能应用。还讨论了可能的光催化机理。ZnO / g-CN基材料的合成程序可用于许多领域，例如环境和储能应用。