| Recently, microwave processing has been developed as a new technique for material preparation, hi general, microwave-assisted reactions are found to be fast, clean, and energy efficient, and most remarkably occur at temperature much lower than those in the conventional processes. Nine of titanic oxides have successfully obtained in the Ti-O, Li-Ti-0 and Mg-Ti-0 systems by using a novel hybrid microwave method which was not reported in the literatures to the best of our knowledge. There are LiTi2O4 of spinel and ramsdellite phase, LiTiO2, Li2Ti3O7, Li2TiO3,Ti2O3, Ti3O5, Ti4O7, MgTi2O4 and Mg1.42Ti1.58O4. Using microwave heating for these oxides synthesis, the evaporation and oxidation of lithium and magnesium can be significantly reduced. The structural and composition analysis were carried out using an X-ray difrractometer and a scanning electron microscope. We also studied the temperature dependence of resistance and the magnetic susceptibility of the samples. The main findings are as follows:1. The well-known superconducting oxide LiTi2O4 has a structural phase transition from spinel to ramsdellite around 900℃ We have successfully obtained the superconducting spinel phase and the non-superconducting ramsdellite phase of LiTi2O4 using a hybrid microwave method. The results show that the low-temperature spinel phase is a superconductor with TC=13K, while the high-temperature ramsdellite phase is a semiconductor. By comparison between the crystal structures of the spinel and the ramsdellite phases, it is suggested that the geometrical frustration plays an important role in the superconductivity of the spinel LiTi2O4.2. The titanic oxides are very interesting materials because of its exotic physical and electrical properties such as superconducting and metal-insulator transition. We have successfully obtained Ti2O3, Ti3O5 and Ti4O7 using the hybrid...
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