Photocatalytic Degradation of Dye Wastewater by NG/TiO2 Composite

N-doped graphene (NG)/TiO2 composites were prepared by a hydrothermal method using HF as the surface etchant and urea as the nitrogen source. The morphology and structure of the NG /TiO2 composites were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS) and specific surface area (BET). The pore size distribution of the composite and the effect of NG addition on the photocatalytic properties were studied. The photocatalytic properties of the composite were evaluated under UV and sunlight conditions respectively. The results show that TiO2 is uniformly loaded on the surface of NG, and NG/TiO2 is mesoporous material. The introduction of NG can effectively improve the photocatalytic properties, 5wt% NG/TiO2 has the best photocatalytic degradation effect on methylene blue. The degradation rate of methylene blue is 96.30% at 30 min under UV and 99.87% at 180 min under sunlight.