氧化钛-氧化石墨插层结构及其光催化性能(英文)

采用氧化石墨(GO)和硫酸钛作为初始反应物,在低温下(80℃)制备了纳米级的氧化钛-氧化石墨插层(TiO2-GO)复合材料,研究了这一复合材料的紫外光催化性能.结果表明,在采用TiO2-GO插层复合材料对甲基橙溶液进行紫外光催化降解时,其降解效率η=1.17mg·min-1·g-1,明显优于德固赛P25氧化钛粉.通过对TiO2-GO插层复合材料进行X射线衍射(XRD)、傅里叶红外(FT-IR)光谱、X射线光电子能谱(XPS)和场发射扫描电子显微镜(FESEM)等测试,表征了产物的晶相结构、界面状况及其显微结构.结果表明:插层结构中的TiO2晶粒为锐钛矿和金红石的混合相,且锐钛矿相含量大于金红石相含量;氧化石墨层间的含氧基团如C襒O,基本被还原.对TiO2-GO插层复合材料的形成机理以及该材料具有优越光催化性能的原因进行了探讨.

Intercalated Structure and Photocatalytic Properties of TiO_2-Graphite Oxide Composite

TiO_2-graphite oxide (TiO_2-GO) composites were successfully prepared at low temperature (80 CC) using graphite oxide (GO) and titanium sulfate (Ti(SO_4)_2) as initial reactants. The photocatalytic properties of TiO_2-GO under UV light irradiation were also studied. Results show that the degradation rate of methyl orange is 1.17 mg·min~(-1)·g~(-1) (referring to the efficiency of the initial 15 min). Compared with Degussa P25 powders, this intercalation composite is far more efficiently. In addition, the crystalline structure, interface status and microscopic structure of TiO_2-GO were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). Result showed that the TiO_2 crystallites in the intercalated structure were composed of anatase and rutile phase with the former phase being enriched. The functional groups present in GO such as carboxyl (C=O) were mostly reduced in the intercalation composite. On the other hand, the synthesis mechanism and the main reasons responsible for the superior photocatalytic properties of TiO_2-GO are also discussed.