压电效应——百岁铁电的守护者

Piezoelectricity—An important property for ferroelectrics during last 100 years

作为电介质大家庭的重要成员,铁电材料以其蕴含丰富的物理性质而闻名,并因此吸引了大量科技工作者.压电效应是铁电材料最为重要的物理性质之一,同时也是目前铁电材料所有物理性质中应用最为广泛的.例如:水声声呐系统、医疗超声探头、压电驱动器等器件的核心压电元件均为铁电材料.本文将以时间为轴,重点介绍钛酸铅基铁电材料压电效应的发展历史,同时讨论铁电材料微观结构、极化状态与压电效应之间的构效关系.本文涉及到影响铁电材料压电效应的一些重要因素,如:"准同型相界"、"软性掺杂"、"极化旋转"、"局域结构无序"等,希望能够在铁电功能材料的设计方面给予读者启发.

As an important member of the dielectric family,ferroelectric materials are known for their various physical properties and have been attracted considerable attention from both scientific respect and technology respect.Piezoelectricity is one of the most important properties of ferroelectrics,which has been widely used in many devices for the conversion between electric energy and mechanical energy.For example,the main piezoelectric elements of underwater acoustic transducers,medical imaging systems,piezoelectric actuators,etc.,are all ferroelectrics.In this paper,the history of the piezoelectric effect in lead-based perovskite ferroelectrics is introduced,and the relationship among the microstructure,the state of polarization and the piezoelectricity is discussed.In addition,we introduce some important factors for optimizing the piezoelectricity of ferroelectrics,such as morphotropic phase boundary,soft doping,polarization rotation,local structural heterogeneity,etc.It is expected that this paper could shed light on the future design of ferroelectric materials with various functionalities.