In this paper, a novel composite photocatalyst, ferric oxide–bismuth oxyhalide (Fe₂O₃-BiOCl_0.5Br_0.5) has been synthesized, characterized, and used for the degradation of methyl orange through advanced oxidation process under ambient conditions (sunlight, pH 7.0, and temperature 25°C). The catalyst has been characterized by using UV-Vis spectrophotometer, Fourier transform infrared (FTIR) spectroscopy, Raman spectrometer, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and X-ray diffractometer (XRD) techniques. The catalyst shows appreciable activities under natural sunlight conditions. From the XRD patterns and SEM images, it is observed that the elongation along the z axis in the crystal lattice of BiOCl_0.5Br_0.5 in the catalyst can lead to a lattice distortion induced internal electric field which can help in charge carrier separation and transport. The Fe₂O₃-BiOCl_0.5Br_0.5 catalyst shows more than 90% photodegradation efficiency of methyl orange in 90 min of sunlight exposure. The presence of magnetic ferric oxide in the composite photocatalyst helps to isolate the catalyst from the reaction mixture by using an external magnet, and thus, the Fe₂O₃-BiOCl_0.5Br_0.5 catalyst can be reused repeatedly, towards degradation of organic pollutants.

中文翻译：

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Fe2O3-BiOCl0.5Br0.5复合光催化剂可见光驱动光催化降解甲基橙

本文合成、表征了一种新型复合光催化剂，氧化铁-卤氧化铋（Fe ₂ O ₃ -BiOCl _0.5 Br _0.5），并用于在环境条件（阳光、pH 7.0，温度 25°C）。该催化剂已通过使用紫外-可见分光光度计、傅里叶变换红外 (FTIR) 光谱、拉曼光谱仪、扫描电子显微镜 (SEM)、能量色散 X 射线分析 (EDX) 和 X 射线衍射仪 (XRD) 技术进行表征。该催化剂在自然光照条件下表现出可观的活性。从 XRD 图案和 SEM 图像中，观察到沿z 轴的伸长率催化剂中 BiOCl _0.5 Br _0.5晶格中的轴可以导致晶格畸变引起的内部电场，这有助于电荷载流子的分离和传输。Fe ₂ O ₃ -BiOCl _0.5 Br _0.5催化剂在90分钟的阳光照射下显示出超过90%的甲基橙光降解效率。复合光催化剂中磁性氧化铁的存在有助于通过使用外部磁铁将催化剂与反应混合物隔离，因此，Fe ₂ O ₃ -BiOCl _0.5 Br _0.5催化剂可以重复使用，以降解有机污染物。