氧化石墨烯对亚甲基蓝的可见光催化降解

Degradation of methylene blue by graphene oxide under visible-light irradiation

用改良的Hummers法制得了氧化石墨烯,对其微观形貌、成分和结构进行了表征,并使用亚甲基蓝溶液测试其光催化效率。通过SEM、TEM、Raman分析表明,得到的是少层氧化石墨烯,碳氧原子数比在3∶1左右。荧光共聚焦光谱显示,所得到的氧化石墨烯在420～700nm的光波谱范围内都有特征吸收峰。氧化石墨烯能够迅速吸附亚甲基蓝分子,然后对其进行光催化降解,在亚甲基蓝浓度为40mg/L、氧化石墨烯浓度为10mg/L时,降解率能达到40%。之后,初步探究了氧化石墨烯的光催化机理。

The graphene oxide was prepared by modified Hummer method.Its microstructure,composition and structure were characterized and the photocatalytic efficiency was tested using methylene blue solution.SEM,TEM and raman analysis showed that few layer graphene oxide was obtained,and the ratio of carbon to oxygen was about 3∶1.Fluorescence confocal spectroscopy showed that the dispersion of graphene oxide had characteristic absorption peaks in the range of 420~700 nm.It was found that the methylene blue molecule was rapidly adsorbed then degraded by the graphene oxide under visible light.The degradation efficiency could reach 40%when the catalyst concentration was10 mg/L and the concentration of methylene blue was 40 mg/L.Its photocatalytic mechanism was also discussed then.