磁性Fe^(n+)@GO非均相Fenton催化氧化亚甲基蓝

Heterogeneous Fenton catalyzed oxidation of methylene blue by magnetic Fe^(n+)@GO

采用化学共沉淀法制备了磁性Fe^(n+)@GO(MFGO)纳米复合材料,并将其用于非均相Fenton催化氧化亚甲基蓝(MB).扫描电镜、透射电镜和光电子能谱分析表明,催化活性粒子(Fe^(n+)/铁氧化物)成功负载在GO表面.实验研究了p H值、H_2O_2初始浓度、催化剂投加量等因素对MB降解效果的影响.结果表明,H_2O_2、MFGO和H_2O_2+MFGO体系在反应120min后,MB降解率分别达到7.83%、25.58%和99.19%;在优化条件为H_2O_2浓度0.79mol/L、MFGO用量0.75g/L、p H值8时,MB降解率可达99.90%;在p H值为3~11范围内,MB降解率均在99%以上;MFGO经过6次重复使用后对MB的降解率仍可达到95.08%,是一种p H值响应宽、可磁分离回收的新型非均相催化剂.

Magnetic Fe^（n＋）@GO（MFGO）nanocomposite was prepared by coprecipitation and applied as a heterogeneous Fenton catalyst for catalytic oxidation of methyl blue（MB）.The scanning electron microscopy（SEM）,High-Resolution transmission electron microscopy（HRTEM）and X-ray photoelectron spectroscopy（XPS）indicated that the GO nanosheets were successfully loaded by catalytically active particles（i.e.,Fe^（n＋）,iron oxide）.The effects of p H value,initial H_2O_2 concentration and catalyst dosage on the degradation efficiency were investigated.The degradation efficiencies for the system of H_2O_2,MFGO and H_2O_2 with MFGO after 120min reached 7.83%,25.58%and 99.19%,respectively.The degradation efficiency of MB was 99.90%at the optimal operating conditions of 0.79mol/L H_2O_2 and 0.75g/L MFGO,p H=8.With the p H ranging from 3to 11,the degradation efficiency of MB was still higher than 99%.Even MFGO was reused for six consecutive runs,the degradation efficiency of MB still reached 95.08%.Furthermore,the novel catalyst was preferable to be utilized in wide p H value and took the advantages in magnetic separation and reuse.