Synthesis and characterization of transparent perovskite nanoparticlepolymer hybrid controlled by external field

以不饱和配体修饰的钡钛醇盐为原料，通过聚合和水解反应合成了透明的BaTiO_3纳米粒子/聚合物杂化材料。BaTiO_3颗粒的结晶度随水解水量的增加而增加。结果表明，随着微晶尺寸的减小，杂化膜的吸收边向短波方向移动，分散在硅油中的SrTiO_3粒子/有机杂化物表现出典型的电流变行为。流体的流动曲线揭示了施加直流电场时的屈服应力。屈服应力依赖于外加电场的大小，并对电场的开关有快速响应。采用直流电场法，在水溶液中以钛有机膜和钡、锶离子为原料，制备了纳米钙钛矿粒子/聚合物复合膜。在不经过高温处理的情况下，在40℃以上的直流电场作用下，不锈钢衬底上的前驱体薄膜中形成了钙钛矿型的晶体颗粒。在3.0V/cm的电压下，在40 ~ 50℃范围内，随着反应温度的升高，钙钛矿的尺寸逐渐增大。在3.0 V/cm和50℃下，从35 min到60 min，随着反应时间的延长，过氧化氢颗粒的尺寸也逐渐增大。

Transparent BaTiO_3 nanoparticle/polymer hybrid was synthesized by polymerization and hydrolysis of barium titanium alkoxide modified with unsaturated ligand. BaTiO_3 particles increased in crystallinity with increasing water amount for hydrolysis. The absorption edge of the hybrid film on silica plates shifted to shorter wavelength with decreasing crystallite size.SrTiO_3 particle/organic hybrid dispersed in silicone oil exhibited a typical electrorheorhogical behavior. The flow curve of the fluid revealed a yield stress on applying DC field. The yield stress was dependent upon the magnitude of the external field, and showed a quick response to the on-off switching of filed. Nanouystalline perovskite particle/polymer composite film was synthesized from titanium-organic film and barium or strontium ion in aqueous solution by applying direct current (DC) field. Crystalline perovskite particles were formed in the precursor films on stainless steel substrates under DC field above 40℃ without high temperature process. The size of perovslite increased with increasing reaction temperature from 40 to 50℃ at 3.0 V/cm. Perovskite particles also increased in size with increasing reaction time from 35 to 60 min at 3.0 V/cm and 50℃.