| The materials of rare earth complex oxides have caught many people's attention because of their well chemical and physic function and application outlook. There are lots of methods to synthesize that kind of materials, but they all have shortcomings. In this thesis, a rheological phase reaction method was introduced to synthesize that kind of materials of which the structure and function were studied. As a new reaction method, the rheological phase reaction method is the process of preparing compounds or materials from a solid-liquid rheological mixture. That is, the solid reactants are fully mixed in a proper molar ratio, and made up by a proper amount of solvents to a solid-liquid rheological state (neither solid nor liquid). The product can be obtained under a suitable experimental condition from the solid-liquid rheological state. In the rheological phase system there are many advantages: the surface area of solid particles can be efficiently utilized, the contact between solid particles and liquid is close and uniform, heat change is very efficient, local overheating can be avoided, and the reaction temperature can be easily controlled. In addition, many substances have greatly increased solubility and taken new reaction behavior.In the paper, two serials of rare earth complex oxides SnRE2O4(RE=YN Dy, Gd, Er) and ZnRE2O4(RE=La, Sm, Eu, Yb) and BaTiO3 powders were synthesized by using rheological phase reaction method. We studied the thermal decomposition mechanism of the precursor by TG and DTA, the pureness and valence by IR, RAMAN and XPS, the structure by XRD and the surface form of all the aimed compounds by SEM and TEM. In the last, the spectroscopy function of the compounds ZnRE2O4(RE=La, Sm, Eu, Yb) was studied by UV and fluorescence spectrometer. The major conclusion of this paper are listed below:1) Two serials of rare earth complex oxides SnRE2O4(RE=YN Dy, Gd, Er)and ZnRE2O4(RE=La, Sm, Eu, Yb) were synthesized by using rheological phase reaction method. We found that no the same compounds was reported after we searched the CA since 1960 year, and that it was the first time to synthesis the rare earth complexIVoxides by using rheological phase reaction method. So we can conclude that no matter the aimed compounds nor the synthesis method we used are innovational and creationary.2) In this paper, the cubic barium titanate was obtained by using rheological phase reaction method from the peroxides precursor. When we try to make sure the structure type at room temperature, we observed that the barium titanate transformed from cubic type to cubic and tetragonal type and to tetragonal type by the RAMAN spectroscopy of the sample synthesized for different hours while at the same temperature. The phenomena can solve the disputations about the particle size of the barium titanate powders when the courier's temperature decreased to bellow the room temperature, and we concluded that the size is below 20nm.3 ) In the paper, all kinds of XRD structure analysis method and its applicational software were studied, and the ab-inio and experience were expatiated e emphatically. And we selected a structure analysis way and many software to solve the structure problem by compare the merit and shortcoming of all the existed structure analysis software. It is innovate of the combination of the structure analysis software in my paper.4) We solved the structure analysis of the SnRE2O4(RE=YN Dy Gd Er) and ZnRE2O4(RE=I SHK Eu Yb) by the structure analysis method and software that we chosed. The results showed that the SnREiCserials had tetragonal type while the ZnRE2O4 serials was spinel structure type. The theory of K.kugimiya and H.steinfink about AB2O4 structure type figured that the SnRE2O4 serials could be spinel type while they were not. The structure type of the SnRE2O4 serials may be a modification to the K.kugimiya and H.steinfink's theory.5) The thermal decomposition mechanism of the oxalate precursor of the SnRE2O4 (RE=Y Dy, Gd, Er) and ZnRE2O4(RE=La Sim E Yb) was studied by TG and DTA, and we foun...
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