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利用普鲁士蓝(PB)作为γ-Fe2O3前驱体,先依次在氧化石墨烯(GO)片上负载PB和CdS纳米粒子,再将其置于惰性气体(N2)氛围下进行煅烧,成功制备出CdS/RGO/γ-Fe2O3三元复合光催化剂.通过改变PB负载量可以得到不同γ-Fe2O3含量的三元光催化剂,且PB的方块状形貌在煅烧后得以保持.利用XRD、EDS、TEM、FT-IR、UV-vis等手段对所制备的样品进行组成、结构、形貌、光吸收等的分析表征,并以罗丹明B (RhB)为模拟污染物研究上述催化剂对有机污染物的光催化降解性能.与二元复合物CdS/RGO相比,三元CdS/RGO/γ-Fe2O3光催化剂表现出更强的可见光催化活性,这说明γ-Fe2O3在光催化过程中起了重要作用.而且,由于γ-Fe2O3具有铁磁性,在外加磁场的作用下可以将光催化剂从反应体系中快速分离回收.同时,还研究了CdS/RGO/γ-Fe2O3光催化剂的降解动力学过程,并通过光催化剂的荧光表征和活性基团捕获实验,提出了光催化降解的机理.“,”With Prussian blue (PB) as the precursor for γ-Fe2O3,the tri-component CdS/RGO/γ-Fe2O3 photocatalyst was prepared through loading PB nanocubes and CdS nanoparticles on graphene oxide (GO) nanosheets,followed by a calcination process in inert atmosphere (N2).The content of γ-Fe2O3 in the CdS/RGO/γ-Fe2O3 photocatalyst can be adjusted by changing the loading amount of PB,and the cubic morphology of PB was maintained after the calcination.The composition,structure,morphology and light absorption of the as-prepared products were investigated by X-ray diffraction (XRD),X-ray energy dispersive spectroscopy (EDS),field emission scanning electron microscopy (SEM),transmission electron microscopy (TEM),infrared spectroscopy (FT-IR),Raman spectroscopy and ultraviolet-visible (UV-vis) spectroscopy.The photocatalytic activity of the ternary photocatalysts was evaluated by the degradation of the organic pollutant of Rhodamine B (RhB) under visible-light irradiation.It was found that the degradation process of RhB follows pseudo-first-order kinetics.Compared to the bi-component CdS/RGO photocatalyst,the tri-component CdS/RGO/γ-Fe2O3 exhibited greatly enhanced photocatalytic activity,demonstrating that the γ-Fe2O3 played an important role in the photocatalytic process.The CdS/RGO/γ-Fe2O3 composite with PB loading amount of 12 mg exhibits the highest photocatalytic degradation efficiency of about 99.8% and the highest apparent reaction rate constant (k) value of about 0.03289 min-1,which is almost 2.9 times and 1.8 times higher than that of CdS and CdS/RGO,respectively.This result indicates that a suitable loading amount of γ-Fe2O3 is important to optimize the photocatalytic performance of the CdS/RGO/γ-Fe2O3 composites.Moreover,owing to the ferromagnetism of γ-Fe2O3,the CdS/RGO/γ-Fe2O3 photocatalyst could be easily separated from the reaction solution for recycling by a magnet.A possible photocatalytic mechanism was also proposed based on the photoluminescence (PL) characterization and the active species capture experiment.It was demonstrated that the enhanced photocatalytic degradation properties of CdS/RGO/γ-Fe2O3 composites can be ascribed to the excellent conductivity of RGO and the construction of Z-scheme heterostructure between CdS and γ-Fe2O3,which facilitate the transport and separation of photogenerated carriers.