Study On Doping Of Tetragonal Titanate And Its Electric Field Response Performance

The barium strontiun titanateparticles in tetragonal crystal structure with novel shape were synthesized by a simple hydrothermal method via controlling reaction conditions. Meanwhile, the reaction parameters were also optimized. The as-prepared particles were characterized by XRD, Raman, SEM and Contact Angle. On this basis, the different kinds of barium strontiun titanate particles were dispersed in gelatin/ glycerol/water mixture system,cured with or without an external dc electric field (1.2 kV/mm), A-elastomers (cured without any electric field) and B-elastomers (cured with 1.2 kV/mm electric field) were prepared. Finally the difference in modulus of a pair of A and B-elastomers were explored and there out the electric response of barium strontiun titanate particles were investigated indirectly. The specific contents are as follows:1. Using barium nitrate, strontium nitrate, tetrabutyl titanate as raw materials, potassium hydroxide as mineralizer, barium strontium titanate crystals were successfully prepared. The crystal structure and morphological characteristics of the as-prepared barium strontium titanate powders were respectively characterized by these techniques such as XRD, Raman, and SEM. The components of sample was determined by ICP-Ms. The results show that the crystal phase of barium strontium titanate is tetragonal phase structure. Moreover, the Sr source was vital to the morphology of the barium strontium titanate. ICP-Ms results showed that the chemical formula of barium strontium titanatewas Ba0.85Sr0.15TiO3.2. Barium strontium titanate particles with walnut-like,spherical shapes were prepared by amorphism TiO2,barium hydroxide, strontium nitrate. XRD, Raman, SEM were used to analyse the structure and morphology of samples. The components of sample was determined by ICP-Ms. Through adjust the hydrothermal conditions, such as (Ba+Sr)/Ti ratio, Ba/Sr ratio, reaction temperature, reaction time. The results show that barium strontium titanate particles which prepared at different conditions are tetragonal phase structure, and the additives play an important role in the morphology. ICP-Ms results showed that the chemical formula of barium strontium titanatewas3. In order to compare the surface hydrophilic of tetragonal barium strontium titanate particles, the water contact angle of the particles were tested. The results show that they are all less than 30±5°, and means that they all possess predominant surface hydrophilic capacity. The dielectric property of particles reveals that the dielectric constant of the tetragonal phase barium strontium titanate was greater than that of tetragonal barium titanate.4. To study the response behavior of differentbarium strontium titanate particles, BST /gelatin/glycerol complex elatomers’ mechanical properties were tested, indicating that the tetragonal BST particles indeed have stronger response ability, and particles tetragonality, surface hydrophilicity, dielectric properties all have a certain effect on the electric field response performance.