纳米二氧化钛/氧化石墨烯的制备及对水中污染物的去除性能研究

Studies on Preparation and Elimination Properties of TiO_2/Graphene Oxide Composites

利用改进Hummers法制备氧化石墨烯(GO),以GO为载体,通过一步溶胶混合法成功制备TiO_2/GO复合催化剂,并利用傅里叶变换红外光谱(FT IR),X射线衍射仪(XRD),透射电子显微镜(TEM)等技术对其进行表征;同时,探究了TiO_2/GO复合催化剂的投加量对罗丹明B(RB)模拟废水的光催化性能和吸附性能的影响,以及最佳投加量时复合催化剂的重复使用性能。结果表明,TiO_2/GO复合催化剂中TiO_2颗粒均匀分布于薄纱状的GO片层两侧。TiO_2/GO复合催化剂投加量为50mg/L时对罗丹明B降解效果最好,在紫外吸光度554nm处罗丹明B溶液的脱色率(即UV_(554)罗丹明B溶液的去除率)和总有机碳(TOC)去除率分别达到99%以上和66.72%。TiO_2/GO复合催化剂的降解性能优于纯TiO_2。TiO_2/GO复合催化剂重复使用5次后,对RB的UV_(554)去除率和TOC去除率依然维持在99%以上和55%左右。TiO_2/GO复合催化剂对RB的吸附30min后基本达到平衡,吸附过程更为符合准二级动力学方程,拟合平衡吸附量Qe为253.8mg/g。

Graphene oxide （GO） was prepared by modified Hummer＇ s method, and TiOz/GO composites were prepared by one-step colloidal blending method using GO as the carrier loaded onto TiOz. The composites were characterized using Fourier transform infrared spectroscopy （FT IR）, X-ray diffraction （XRD） and Transmission electron microscope （TEM）. The effect of dosage of the composites on the properties of photocatalysis and adsorption on Rhodamine B （RB） was investigated and reusable performance at the best dosage of TiO2/GO composites were also studied The results show that TiO2 nanoparticles distribute on both sides of GO layer symmetrically. The degradation of RB reached to the best result when the dosage of TiO2/GO composites was 50 mg/L, and the decolorization rate of Rhodamine B solution at 554 nm （that is, the elimination rate of UV554 RB solution） and the elimination efficiency of total organic carbon （TOC） could be above 99% and 66.72%. The degradation performance of TiO2/GO composites is better than that of pure TiO2. After using 5 times repeatedly, the elimination efficiency of UV554 and TOC could he still above 99% and 55% approximately. The adsorption interaction between TiO2/GO composites and RB reaches the balance after 30 min, and the process conforms to the pseudo- second-order kinetics equation. The fitting equilibrium adsorption quantity Qc is 253.8 mg/g.