≤10nm钛酸钡颗粒调控的高性能聚合物基复合材料的储能机理研究

电介质电容器是智能电网、大功率激光武器、新能源技术等领域不可替代的重要储能元件，在电子和电气工业中具有广泛的应用。研发兼具高介电常数和击穿场强的介质材料是提升电介质电容器储能密度的关键。针对现有陶瓷-聚合物基复合材料体系中，无机填充相导致的击穿场强恶化的关键问题，本项目提出基于≤10nm的BaTiO3铁电颗粒的聚合物基介电复合材料，拟通过极细尺寸铁电颗粒特殊的物理、化学、电学及界面等纳米尺寸效应，调控复合材料的显微结构和电荷、电场分布，有效提升复合材料的电位移极化并保持其耐击穿性能。综合运用纳米制备、包覆改性、多尺度结构设计的实验手段，结合有限元分析、相场模拟的理论方法，研究≤10nm钛酸钡颗粒的纳米尺寸效应，探明其对复合材料储能特性的影响机理，设计制备一系列储能密度≥20J/cm3的复合电介质薄膜，为高储能密度介电复合材料的发展提供一种新的技术路径。

Dielectric capacitors are irreplaceable energy-storage components in pulsed power systems, which are widely applied in electric and electrical industry. Developing materials with high dielectric constant as well as high breakdown strength is very important in improving the energy density of dielectric capacitors. As most of the high-polarization ceramic fillers deteriorate the dielectric strength of the polymer composite, this project will develop nanocomposite films based on ultrafine (≤ 10 nm) BaTiO3 ferroelectric nanocrystal fillers to solve the problem. The ultrafine fillers with specific physical, chemical, electrical and interface characteristics can optimize the microstructure and charge distribution of the composite, therefore effectively improve the electric displacement while maintain the initial high breakdown strength of the composite. Dielectric composite films with energy density ≥20 J/cm3 will be prepared. This project combines various experimental methods, including nanotechnology, coating and multilayer design, and finite element and phase field simulations to detect the influence of the ultrafine ferroelectric nanocrystals on the dielectric performance of the polymer nanocomposite films, which provides a new technological way for the design of high energy-density composite films.