In this research, graphitic carbon nitride (g-C₃N₄) photocatalysts were synthesized through a simple calcination process at various temperatures, which were 400, 500, 550, and 600 °C, by using low-cost urea as a precursor. The obtained g-C₃N₄ samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) surface area and porosity analyses, and ultraviolet–visible-near-infrared (UV–VIS-NIR) spectroscopy. The correlations between the calcination temperature, properties, and photocatalytic activity of prepared products were investigated. The results demonstrated that the g-C₃N₄ photocatalysts can be successfully synthesized at temperatures of 500–600 °C with a controlled heating rate of 5 °C/min. In contrast, the intermediate product was observed in sample calcined at 400 °C. It was demonstrated that calcination at higher temperatures possibly increased the active sites and enhanced both of the photocatalytic activity and dye adsorption ability. Herein, the dye degradation efficiency (DE%) under visible light irradiation within 10 min were presented as 2.52, 16.01, 62.37, and 92.64% which were well developed as a function of calcination temperature from 400 °C, 500 °C, 550 °C, to 600 °C, respectively. Furthermore, the dye degradation rate could possibly induce decomposition pathway of rhodamine B. The photocatalytic efficiency was maintained after four times of reuse. It can be concluded that the thermal process plays an important role in controlling the properties and photocatalytic performance of g-C₃N₄.

在这项研究中，使用低成本的尿素作为前体，通过简单的煅烧工艺，在400、500、550和600℃的各种温度下，通过简单的煅烧过程合成了石墨氮化碳（gC ₃ N ₄）光催化剂。通过X射线衍射（XRD），傅立叶变换红外光谱（FT-IR），透射电子显微镜（TEM），Brunauer-Emmett-Teller（BET）表面积和孔隙率分析对获得的gC ₃ N ₄样品进行表征紫外可见近红外（UV-VIS-NIR）光谱。研究了煅烧温度，性质和制备产物的光催化活性之间的相关性。结果表明，gC ₃ N ₄光催化剂可以在500-600°C的温度下以5°C / min的受控加热速率成功合成。相反，在400℃下煅烧的样品中观察到中间产物。结果表明，在较高的温度下煅烧可能会增加活性位点，并增强光催化活性和染料吸附能力。本文中，在10分钟内可见光照射下的染料降解效率（DE％）表示为2.52、16.01、62.37和92.64％，它们分别是煅烧温度从400°C，500°C，550°开始的函数。 C，分别至600°C。此外，染料的降解速率可能会引起若丹明B的分解途径。重复使用四次后，光催化效率得以保持。₃ N ₄。