SusChEM: Elucidating structure-property relationships in lead-free piezoelectrics

非技术描述：由于压电材料可用作执行器和传感器的元件，因此具有广泛的应用。行业标准和研究最多的是PZT(PZT)。PZT的一个主要问题是铅，它会使制造工人处于危险之中，并在处置基于PZT的部件时向环境中引入危险废物。新的压电材料显然是有必要的，但目前还没有很好的替代PZT的方法。许多对PZT的研究已经使人们对PZT的晶体结构如何有助于增强性能有了详细的了解，但对其无铅对应物的结构知之甚少，减缓了它们在应用中的发展。本研究的目的是研究两种关键的无铅压电材料的基本结构与性能之间的关系。这项研究提供了一个基本的理解，有助于开发良性的压电材料，以提高电子器件的可持续性。该项目还致力于扩大学生教育的机会，并致力于招募和留住科学和工程领域的年轻科学家。技术细节：这项研究促进了对压电陶瓷结构-性能关系的基本理解。本项目的目标是评估两种著名的无铅压电材料在准同型相界(MPB)的平均结构的局部失真，并将结构信息与测量性能的观察相关联。目前，最有前途的无铅压电材料BaTiO3BiInO3系和非传统MPB型系BaTiO3BiInO3系正在研究中。人们正在研究极化和非极化的系统，以考察真实条件下的结构变化。这些详细的结构研究利用X射线和中子衍射以及EXAFS，并使用对分布函数方法和反向蒙特卡罗模拟进行分析。此外，该项目旨在招聘和留住STEM领域的年轻科学家，并培养研究生在他们的职业生涯中脱颖而出。研究生正在参加The Lens of the Market®项目，学习如何将他们的可持续研究想法转化为创新，以解决市场问题。一年级和二年级的本科生将有机会在实验室工作，并获得早期的研究经验，从而增加在STEM领域的留存率。参加青少年科学与工程暑期体验(SESEY)暑期项目的高中女性和少数民族学生将参与可持续的压电学研究，以参与国家的科学和工程事业。

NON-TECHNICAL DESCRIPTION:Piezoelectric materials are found in a wide variety of applications as they can be used as components in both actuators and sensors. The industry standard and most commonly studied piezoelectric is Pb(Zr,Ti)O3 (PZT). A major concern in PZT is the lead, which puts manufacturing workers at risk and, introduces hazardous waste into the environment upon disposal of PZT-based components. The necessity for new piezoelectric materials clearly exists, but there is currently no good substitute for PZT. Many studies of PZT have led to a detailed understanding of how the crystal structure contributes to the enhanced properties, but little is known about the structures of its lead-free counter parts, slowing their development for use in applications. The aim of this study is to investigate the fundamental structure-property relationships in two key lead-free piezoelectric materials. The research provides a fundamental understanding that aids in the development of benign piezoelectric materials to improve the sustainability of electronic devices. This project is also strongly committed to expanding the opportunities available in student education and works to recruit and retain young scientists in science and engineering fields.TECHNICAL DETAILS:This research advances the fundamental understanding of structure-property relationships in piezoelectric ceramics. The goal of this project is to assess the local distortions from the average structure of two well-known lead-free piezoelectric materials at their morphotropic phase boundary (MPB) and correlate the structural information to observations of the measured properties. Ba,Ca(Zr,Ti)O3, the most promising lead-free piezoelectric material to date, and BaTiO3-BiInO3, a system with a non-traditional MPB are being investigated. Systems are being studied both poled and unpoled to examine the structural changes under real conditions. These detailed structural studies utilize X-ray and neutron diffraction as well as EXAFS, with analysis using the Pair Distribution Function method and Reverse Monte Carlo modelling. In addition, this project aims to recruit and retain young scientists in STEM fields and train graduate students to excel in their careers. Graduate students are participating in the Lens of the Market® program to learn how to translate their sustainable research ideas to innovation with the purpose of solving market problems. Freshman and sophomore undergraduates will be given the opportunity to work in the lab and gain the early research experiences that result in increased retention in the STEM fields. High school women and minority students in the Summer Experience in Science and Engineering for Youth (SESEY) summer program will participate in sustainable piezoelectric research to become engaged in the nation's science and engineering enterprise.