| Controllable synthesis of nanostructures and its application have been a focus in areas of materials. The methodology study on nanosized materials has received significant progresses in the past ten years. Particularly, regarding the synthetic methods for nanoparticles, solution-phase approach has been one of the most important methods. As one of the most important rare-earth compounds, ceria has wide application in many fields, such as catalyze, sensor, photoelectricity and so on. Owing to their unique optical, electronic, and magnetic properties, semiconductor nanomaterials (such as SnO2 and ZnO) also have been attracted much attention in recent years. Meanwhile, due to the excellent piezoelectric, ferroelectric and photoelectric properties, bismuth titanate is a promising material for the applications in the relative filed.This paper focused on fabrication of nanoscale oxides by solution-phase method. In addition, formation mechanism and properties of as-prepared nanostructures were also investigated. The detailed information of the paper is listed as follows:1. Fabrication of CeO2 hollow spheres with the assistance of surfactantWe have synthesized CeO2 hollow spheres in the solvent of ethanol with the assistance of the soft template which formed by surfactant under solvothermal conditions.The diameter of the hollow spheres was estimated to be in the range 120-180 nm,and the shell thickness was about 40 nm. The shells of the hollow spheres are composed of numerous nanocrystals with an average size of 15 nm. On basis of the experiment results, it is indicating that the solvent played a great role in the formation of the CeO2 nanostructures,When n-CmH2m+1OH(m≤3) was applied as the solvent, hollow spheres were obtained. However, only CeO2 cubic nanostructures were obtained when the solvent was n-CmH2m+1OH(m≥4).2. Synthesis of SnO2 and ZnO nanoparticles via a simple solution-phase methodHigh dispersed SnO2 and ZnO nanoparticles were successfully synthesized via solution-phase method in company with supercritical carbon dioxide anti-solvent precipitation technology (SAS). The experimental results showed that the calcination temperature had a remarkable influence on the phase and morphology of the product. Moreover, fabricated rutile SnO2 nanoparticles show high sensitivity and excellent adsorption to ethanol gas.3. Preparation of willow leaf-like Bi4Ti3O12 nanosheets by chemical solution decomposition methodWe have prepared Aurivillius compound Bi4Ti3O12 by chemical solution decomposition method. And when Bi4Ti3O12 was treated with nitric acid, oriented assembly Bi4Ti3O12 was obtained because of (Bi2O2)2+ was dissolved in nitric acid firstly. Compared with its precursor Bi4Ti3O12, the Bi4Ti3O12 after acidification exhibits a distinct blue shift in UV-Vis spectrum and the photocatalytic activities of Methyl orange was much elevated.4. Fabrication of bismuth titanate nanostructures by chemical solution decompo-sition methodAfter heat treatment, bismuth titanate nanostructures were obtained by tuning the molar ratio of Bi to Ti of the precursors. On the basis of the experiment, it is indicated that the element Bi should be transformed to bismuth oxide or Bi12TiO20 by calcination.α-Bi2O3 was the product when the content of Bi is higher than that of Ti, contrarily,β*Bi2O3 was obtained. Compared with bismuth oxide, it is not favorable to obtain tin oxide at low temperature. Moreover, it is worth noting that no tin oxide compound was obtained if Bi existed in the precursors.
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