Abstract:

The pollution of antibiotics in the water environment has been widely concerned, and the photocatalytic technology has a good application prospect in this field. Semiconductor composite construction of Z-scheme heterojunctions can improve carrier separation efficiency and thus photocatalytic degradation efficiency. Herein, CoFe₂O₄/BiFeO₃ Z-scheme heterojunctions were prepared by hydrothermal method and characterized for their structural and photomagnetic properties, which were applied to the photocatalytic degradation of safranin hydrochloride and comprehensively evaluated for their photocatalytic performance. The results showed that the composite catalyst had good optical and magnetic response properties. The degradation rate reached 86.76% at 120min of reaction with a composite heterojunction with a 1∶2 ratio of CoFe₂O₄ and BiFeO₃, a catalyst dosage of 20mg, a pollutant concentration of 5mg/L, and a pH of 3, with good stability. The active substances controlling the reaction were holes and superoxide radicals, and the construction of Z-scheme heterojunctions led to the improvement of their photocatalytic performance. The CoFe₂O₄/BiFeO₃ Z-scheme heterojunctions were environmentally friendly and could be applied to the degradation of antibiotics in aqueous environments. This study provides a feasible idea for the photocatalytic degradation of antibiotics and other organic pollutants.

Key words: CoFe₂O₄, BiFeO₃, photocatalytic oxidation, berberine hydrochloride, pollutant degradation, degradation mechanism

摘要：

抗生素在水环境中的污染问题已经受到广泛关注，而光催化技术在该领域具有较好的应用前景。半导体复合构建Z型异质结能够提高载流子分离效率，进而提高光催化降解效率。本文采用水热法制备了CoFe₂O₄/BiFeO₃ Z型异质结，并对其结构及光磁性能进行表征，将其应用于光催化降解盐酸黄连素，综合评价其光催化性能。结果表明：复合催化剂具有良好的光和磁响应性能；在使用CoFe₂O₄和BiFeO₃比例为1∶2的复合异质结，催化剂用量为20mg，污染物浓度为5mg/L，pH为3时，反应120min的降解率达到86.76%，且该异质结展现出较好的稳定性。控制反应的活性物质为空穴和超氧自由基。Z型异质结的构建使得其光催化性能提高。CoFe₂O₄/BiFeO₃ Z型异质结有良好的环境友好性，可应用于水环境中抗生素的降解。该研究为光催化降解抗生素等有机污染物提供了一个可行性思路。

关键词: 铁酸钴, 铁酸铋, 光催化氧化, 盐酸黄连素, 污染物降解, 降解机理