带状γ-Fe2O3/ZnO异质结光催化剂光催化降解四环素

针对传统ZnO光催化活性不高的问题，采用Zn(CH₃COO)₂和FeCl₃作为ZnO和Fe₂O₃的前驱体，水热条件下采用“一锅法”制备带状γ-Fe₂O₃/ZnO异质结光催化剂，采用XRD、BET比表面积测量仪、TEM、紫外-可见漫反射、电子顺磁共振(EPR)等对其晶体化学结构进行表征。在可见光光源下，探究了不同γ-Fe₂O₃负载量时γ-Fe₂O₃/ZnO异质结光催化剂对四环素的光催化降解的效果。研究表明，ZnO负载γ-Fe₂O₃后比表面积和光照吸收显著改善，禁带宽度有所减小，可见光光照120 min，n(Zn)∶n(Fe) (原子比)为20∶1的γ-Fe₂O₃/ZnO异质结光催化剂对四环素的降解率高达97.2%，多次重复使用后四环素的降解率保持在95%以上。 

Photocatalytic degradation of tetracycline by band-like γ-Fe2O3/ZnO heterojunction photocatalyst

In order to solve the problem of poor photocatalytic activity of traditional ZnO, band-like γ-Fe₂O₃/ZnO heterojunction photocatalyst was prepared by an one-pot method under hydrothermal conditions using Zn(CH₃COO)₂ and FeCl₃ as precursors in this paper. The chemical structure of as-prepared γ-Fe₂O₃/ZnO heterojunction photocatalyst was characterized by XRD, BET specific surface area tester, TEM, UV-Vis diffuse reflection and electron paramagnetic resonance (EPR). The tetracycline photodegradation by the γ-Fe₂O₃/ZnO heterojunction photocatalyst with different loading of γ-Fe₂O₃ was explored under visible light. The results show that due to γ-Fe₂O₃ loading onto the ZnO, the specific surface area and light absorption significantly increase, while the band gap reduces. After visible light illumination about 120 minutes, the photodegradation ratio of tetracycline is up to 97.2% by γ-Fe₂O₃/ZnO heterojunction photocatalyst when n(Zn)∶n(Fe) (atomic ratio) is 20∶1, and the tetracycline photodegradation ratio remains above 95% after repeated use.