Novel graphitic carbon nitride (g-C3N4)/potassium bismuth ferrite (KBiFe2O5) composite photocatalysts were synthesized using facile grinding and calcination method. X-ray diffraction, transmission electron microscopy, scanning electron microscopy and UV–visible diffuse reflectance spectroscopy analysis were carried out to investigate structural, morphological and optical properties of the prepared samples. The photocatalytic properties of the samples were studied by photocatalytic degradation of methylene blue under visible light irradiation. The composite showed enhanced photocatalytic efficiency compared to both pristine g-C3N4 and KBiFe2O5. Out of four composites with different weight percentages of KBiFe2O5, one with 30 wt% showed the maximum photocatalytic efficiency. Samples with a higher content of KBiFe2O5 showed decreased photocatalytic efficiency indicating 30 wt% as the optimum composition. The increase in the photocatalytic efficiency is mainly due to efficient charge separation of photo-generated electron–hole pairs in the composites. The possible mechanism for the photo-catalysis of g-C3N4/KBiFe2O5 composites was also proposed.

中文翻译：

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具有增强光催化效率的新型 g-C3N4/KBiFe2O5 复合材料的合成

使用简便的研磨和煅烧方法合成了新型石墨氮化碳（g-C3N4）/钾铋铁氧体（KBiFe2O5）复合光催化剂。进行X射线衍射、透射电子显微镜、扫描电子显微镜和紫外-可见漫反射光谱分析以研究制备的样品的结构、形态和光学性质。通过在可见光照射下光催化降解亚甲基蓝来研究样品的光催化性能。与原始 g-C3N4 和 KBiFe2O5 相比，该复合材料显示出更高的光催化效率。在具有不同重量百分比 KBiFe2O5 的四种复合材料中，一种具有 30wt% 的光催化效率最高。具有较高 KBiFe2O5 含量的样品显示出光催化效率降低，表明 30 wt% 是最佳组成。光催化效率的提高主要是由于复合材料中光生电子-空穴对的有效电荷分离。还提出了 g-C3N4/KBiFe2O5 复合材料光催化的可能机制。