Abstract The binary flower-like BiOI/CoFe2O4 photocatalysts with magnetic retrievability were successfully synthesized via coprecipitation method. The effects of composite ratio on the microstructure, morphology, optical, photo-electrochemical and photocatalytic properties of the samples were studied. The experimental results show that BiOI/CoFe2O4 nanocomposites contain tetragonal structure BiOI and cubic spinel structure CoFe2O4 with good crystallization. Spherical CoFe2O4 nanoparticles are uniformly decorated on the surface of BiOI nanosheets to establish hierarchical flower-like 3D- BiOI/CoF2O4 heterojunctions. BiOI/CoFe2O4 nanocomposites show excellent visible light absorption ability. PL spectra show the intensity decrease for BiOI/CoFe2O4 nanocomposites. BiOI/CoFe2O4 nanocomposites can promote the separation of photon-generated carriers, improve the migration efficiency, and improve the redox activity of nanocomposites. BiOI/CoFe2O4 nanocomposites exhibit better photocatalytic activity during the process of degrading the RhB dye solution under the irradiation of simulated visible light. The degradation efficiency of BiOI/CFO-3 photocatalysts is 80.24% after 3 cycles, and exhibit better recyclable stability. Also, ·O2− is the main reactive species in the degradation process, which plays a crucial role in the RhB degradation.

中文翻译：

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共沉淀法合成的分级花状BiOI/CoFe2O4纳米复合材料的光电化学和光催化性能

摘要 采用共沉淀法成功合成了具有磁性可回收性的二元花状BiOI/CoFe2O4光催化剂。研究了复合配比对样品微观结构、形貌、光学、光电化学和光催化性能的影响。实验结果表明，BiOI/CoFe2O4纳米复合材料含有四方结构的BiOI和立方尖晶石结构的CoFe2O4，结晶良好。球形 CoFe2O4 纳米粒子均匀地装饰在 BiOI 纳米片的表面，以建立分层的花状 3D-BiOI/CoF2O4 异质结。BiOI/CoFe2O4 纳米复合材料显示出优异的可见光吸收能力。PL 光谱显示 BiOI/CoFe2O4 纳米复合材料的强度降低。BiOI/CoFe2O4 纳米复合材料可以促进光生载流子的分离，提高迁移效率，提高纳米复合材料的氧化还原活性。BiOI/CoFe2O4纳米复合材料在模拟可见光照射下降解RhB染料溶液的过程中表现出更好的光催化活性。BiOI/CFO-3光催化剂在3次循环后的降解率为80.24%，并表现出更好的可回收稳定性。此外，·O2-是降解过程中的主要反应物质，在RhB降解中起着至关重要的作用。并表现出更好的可回收稳定性。此外，·O2-是降解过程中的主要反应物质，在RhB降解中起着至关重要的作用。并表现出更好的可回收稳定性。此外，·O2-是降解过程中的主要反应物质，在RhB降解中起着至关重要的作用。