介质对Nafion膜孔腔中限域TiO_2纳米晶体形成的影响

Effects of Media on the Formation of Nanocrystalline TiO_2 Located in Cavities of Nafion

本文在前期工作基础上,利用高分辨电子显微镜(HRTEM)、X射线衍射仪(XRD)、扫描电镜(SEM),能谱(EDAX)研究了在全氟磺酸离子交换膜(Nafion)模板中有机浸泡液溶剂种类、Nafion膜含水量对前驱体Ti(OBu)4在Nafion模板中形成单分散的TiO_2纳米晶体的影响;研究了Nafion膜断面各元素含量的面分布、线分布、TiO2的含量、粒子大小、纳米晶体微观形貌及其结构。研究结果表明,溶剂决定了Ti(OBu)4在Nafion膜中的荷载量及相应TiO2荷载量的大小;Nafion膜含水量不同,对膜中TiO2荷载量影响很大,但对TiO2晶形、晶粒大小和各元素在Nafion膜断面中的均匀分布没有显著影响。

The effects of the soaking organic solvent and water content of Nafion membrane on the formation of highly dispersed nanocrystalline TiO2 from Ti(OBu)(4) in Nafion template were studied by High resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray analysis (EDAX) on the basis of the previous work. The line and surface distribution of each element. the size distribution and the microstructure of TiO2 on the cross section of Nafion membrane were discussed. Results show that the quantity of Ti(OBu)(4) and TiO2 in Nafion depends on the soaking solvent. A correlation between the water content in Nafion and the quantity of TiO2 formed was observed. However, the morphologies and the grain size distribution of nanocrystalline TiO2 in Nafion was not influenced by the water content in Nafion. EDAX analysis indicated that the line and surface distribution of every element content on the cross section of Nafion membrane were symmetrical.