Preparation Of MTiO₃ （M=Mg, Zn, Sr） Nanomaterials

Magnesium titanate (MgTiO3) as an excellent microwave dielectric material has the following properties:low dielectric loss, moderate dielectric constant and near zero temperature coefficient of resonant frequency. Thus, MgTiO3 has wide applications in low-loss microwave resonators, capacitors, filters, cellular telephones, radars, direct broadcasting satellites and global positioning system operating at microwave frequencies. Zinc titanate and strontium titanate are the important functional ceramic materials. Therefore, many researches are focused on preparation, application of magnesium titanate, zinc titanate and strontium titanate. In this paper, we combine the sol-gel method with the molten salt method to prepare magnesium titanate and zinc titanate, simultaneously we use the molten salt method to prepare magnesium titanate and strontium titanate, and the influence of various factors on the synthesis process of these materials is investigated.In the current work, we combine the sol-gel method with the molten salt method to prepare magnesium titanate, and the influence of the citric acid and acetic acid as the chelating agent is investigated. The results indicate that magnesium titanate particles can be synthesized over 600℃ by using the citric acid and the acetic acid. The particle size is nano-scale and well-dispersed. Magenesium titanate nanoplatelets are prepared by molten salt method at low temperature. By investigating the influence of the existence of the molten salt, magnesium source, holding time, we obtain that using magnesium nitrate as the magnesium source can prepare high purity magnesium titanate over 400℃. Magnesium titanate sintered at 900℃ for 3 h shows some sintering properties.In the last chapter, we combine the sol-gel method with the molten salt method to prepare zinc titanate nanoparticles, and use the molten salt method to prepare the strontium titanate nanoparticles. The results indicate that the grain size of the zinc titanate is of about 30 nm in diameter and 10 nm in thickness and well-dispersed. We can avoid the generation of the anatase TiO3 phase when using the molten salt method to prepare strontium titanate, and the strontium titanate nanoparticles possess regular morphology.