【作者】 谢浩；

【导师】 韩建军； 李远志；

【作者基本信息】 武汉理工大学 ， 建筑材料与工程， 2010， 硕士

【摘要】 本论文用逐层沉积水解FeCl3的方法制备了三维有序的Fe2O3薄膜。并且用扫描电镜,X射线衍射分析,紫外可见漫反射吸收光谱对其进行了分析。样品均有三维有序,且互相连通的大孔结构,孔径为340nm,并且墙体材料属于赤铁矿型的α-Fe2O3(晶粒尺寸为27.2nm)。在有双氧水存在,可见光照射的情况下,三维有序大孔的纳米晶Fe2O3薄膜降解染料的速率常数是无孔纳米晶α-Fe2O3薄膜的2.4倍,并且表现出良好的光催化活性。我们制备的三维有序大孔纳米晶薄膜比参比的Fe2O3薄膜具有较高的可见光催化活性,原因是它具有独特的纳米结构以及规则的三维有序大孔结构,而这种三维有序大孔结构使得前者比后者能够捕获更多的光能量和具有更远的光传输轨道。我们同时进行了改变角度的固相单色光催化实验来研究光学带隙对于三维有序大孔Fe2O3薄膜的光催化活性的影响。我们证明了通过光学带隙的红边调整到电子禁带宽度的附近,可以得到慢光子增强效应,从而提高样品的光催化活性。我们也研究了在双氧水存在的情况下三维有序大孔Fe2O3薄膜降解结晶紫染料的机理。此外,本论文依据相同的方法通过逐层水解醋酸锌制备了三维有序ZnO薄膜,并且进行了扫描电镜,X射线衍射分析,紫外可见漫反射吸收光谱对其进行了分析。结果证明：样品均有三维有序,且互相连通的大孔结构,孔径为270nm,并且墙体材料属于六角纤锌矿ZnO,三维有序ZnO薄膜降解结晶紫的速率常数为参比ZnO的2.4倍,三维有序ZnO的光电流为参比ZnO的1.8倍。由此可见,由本论文方法制备的三维有序大孔纳米晶材料可以用来设计高效的光电化学材料和光催化材料和太阳能及环境治理装置。因为这种材料具有内部相连的大孔结构和纳米尺寸的墙体材料,结合了纳米材料以及反蛋白石材料的优点。更多还原

【Abstract】 A facile approach of layer-by-layer depositing and hydrolysis of FeCl3 is developed to fabricate 3D-ordered Fe2O3 film. The 3D-ordered Fe2O3 film was characterized by SEM, XRD, and DRUV-vis. It has 3D-ordered interconnecting macropores (340 nm) with nanocrystalline hematite Fe2O3 walls (27.2 nm). The 3D-ordered macroporous nanocrystalline Fe2O3 film exhibits 2.4 times larger photocatalytic activity for the photodegradation of dye in the presence of H2O2 under visible irradiation than the nanocrystallineα-Fe2O3 film without macropores, and very good photostability. The much higher photocatalytic activity of the 3D-ordered macroporous nanocrystalline Fe2O3 film than that of the reference Fe2O3 film is attributed to the unique nanostructure and architecture of the 3D-ordered Fe2O3 film, which result in the much greater light harvesting efficiency and efficient mass transport in the former than in the latter due to the existence of 3D-ordered interconnecting macropores. The effect of photonic stop band on the photocatalytic activity of the 3D-ordered Fe2O3 film was studied by angle-dependent solid state photodegradation experiments with monochromatic irradiation. A slow-photon enhancement of photocatalytic activity was achieved by adjusting the red edge of photonic stop band of the 3D-ordered Fe2O3 film close to the electronic bandgap of Fe2O3. The photodegradation mechanism of crystal violet on the 3D-ordered Fe2O3 photocatalyst in the presence or absence of H2O2 was discussed.Besides,3D-ordered ZnO film was fabricated via the same method, and was characterized by SEM, XRD, and DRUV-vis.The sample has 3D-ordered interconnecting macropores (270 nm) with nanocrystalline spiauterite ZnO walls. The 3D-ordered macroporous nanocrystalline ZnO film exhibits 2.4 times larger photocatalytic activity for the photodegradation of dye than the nanocrystalline ZnO film without macropores.These architecture characteristics of inverse opal are useful for designing high efficient photoelectrochemical and photocatalytic materials or devices that are very significant to solar energy utilization and environmental detoxification. We combined the advantages of nanosizedα-Fe2O3 and inverse opal ofα-Fe2O3 together.更多还原