钛酸钡基压电陶瓷的强非本征压电效应与电畴结构调控

The environment-friendly lead-free piezoelectric ceramics have attracted much attention now. The extrinsic piezoelectric response usually plays an important role in the whole piezoelectric response of many piezoelectric ceramics. Systematical studies on the extrinsic piezoelectric response are very important for the search of ceramic materials with high piezoelectric activities. In this project, we will conduct systematical studies on the strong extrinsic piezoelectric response of BaTiO3 ceramics to explore the origin mechanisms of the extrinsic piezoelectric response; Search for the method to improve the extrinsic piezoelectric response by carefully examining the relationship between the extrinsic piezoelectric response and domain configurations; And fabricate BaTiO3-based ceramics with super high piezoelectric activities(d33>800pC/N) by the domain configuration adjustment. The implementation of this project will promote the establishment of mechanism theory of extrisic piezoelectric response of ceramics. It will benefit to the research of not only barium titanate ceramics but also other piezoelectric ceramics. Futhermore, developing BaTiO3-based lead-free piezoelectric ceramics with super high piezoelectric activities(d33>800pC/N) will accelerate the replacement of lead-based piezoelectric material and contribute to the sustainable development of society.

环境友好型无铅压电陶瓷研究是当前国内外材料领域的一个前沿方向。非本征压电效应是陶瓷压电效应的重要组成部分，对非本征压电效应的系统性研究对于提高陶瓷的压电活性具有重要意义。本项目拟通过对钛酸钡陶瓷中的强非本征压电效应的研究，探讨非本征压电效应的起源机制；通过对电畴结构与非本征压电效应的关联问题探索，探讨提高非本征压电效应的方法，最终获得d33>800pC/N的超强压电活性的钛酸钡陶瓷。开展本项目的研究，在理论方面，可形成有关陶瓷非本征压电效应的物性理论,不仅对钛酸钡陶瓷具有重要意义，对其他压电陶瓷的研究也具有重要的指导价值；在应用方面，研制d33>800pC/N的超强压电活性钛酸钡基无铅压电陶瓷，可加速取代含铅压电材料，为社会的可持续发展做出贡献。

非本征压电响应是陶瓷压电响应的重要组成部分。电畴结构的变化是影响非本征压电响应的总要因素。通过调节陶瓷的电畴结构获得强非本征压电响应是提高陶瓷压电活性的重要手段。本项目采用传统固相反应工艺，通过优化原料、粉体制备工艺和陶瓷烧结工艺，制备出了d33高达501pC/N，d33*高达870pm/V的钛酸钡陶瓷，研究了其电畴结构的变化和压电晶粒尺寸效应，明确了非本征压电效应与畴壁振动密切相关的起源机制；通过采用不同的原料和不同烧结气氛制备钛酸钡陶瓷，获得了不同的压电晶粒尺寸效应。通过研究BaTiO3陶瓷畴壁密度、电畴宽度、畴壁有效质量等因素对非本征压电效应的影响，明确了人字形电畴对畴壁非本征压电效应的减弱机制，为非本征压电效应的调控奠定理论基础；研究了极化条件、不同Ba/Ti比、掺杂改性等对钛酸钡电畴结构的影响，积累了一定的电畴结构和非本征压电效应调控的技术手段。