Fabrication And Characterization Of Metal Oxides Hollow Structures By Template Method

In recent years, hollow spheres have attracted a great deal of attention due to their potential applications in catalysts, sensors, electrochemistry, magnetic and optical application. So several techeniques have been used to fabricate hollow spheres, among these methods, template methods is an efficient method to synthesize hollow structures because of its unique advantage.1. In this paper, a novel route to synthesize manganese oxide (MnO₂) hollow urchins via a reactive template of carbon spheres is described. The results of scanning electron microscopy and transmission electron microscopy indicate that the MnO₂ shows hollow urchins structure with an average diameter of 1.5μm and the cavities with diameter of about 250-500 nm. It has a high Brunauer-Emmett-Teller surface area of 110 m2/g and a mesoporous structure. The formation process of the MnO₂ hollow urchins and the removal mechanism of carbon spheres are suggested. In addition, the magnetic properties of theγ-MnO₂ hollow urchins are investigated.2. C/CuS composite spheres have been prepared under the hydrothermal process using metal salt-S2- sources-glucose as the precursors,.After synthesis, C/CuS composites were calcined to remove the carbon core ,leading to CuO hollow spheres. The results reveal that the diameter of the C/CuS structure is 3-5μm and the diameter of CuO hollow spheres is about 2-4μm. The formation process of the C/CuS core-shell structure and CuO hollow spheres are suggested. At the same time, we sutidies the catalytic properties of .CuO hollow spheres.3. C/CdS composte spheres have been synthesized by a simple hydrothermal process. After synthesis, C/CdS composites were calcined to remove the carbon core ,leading to produce CdO materials The results of scanning electron microscopy indicate that CdS membrane encapsulated several carbon spheres to form a big spherical structure,The diameter of the whole spheres is 3-5μm and the diameter of carbon spheres is about 2μm. In addition, the catalytic properties of the CdO materical are investigated.