JMR Focus Issue on Lead-free Ferroelectric Materials

The year of 2021 is the 100th anniversary of the first publication of ferroelectric behaviour in Rochelle salt, focusing on its piezoelectric properties. Over the past many decades, people witnessed a great impact of ferroelectricity on our everyday life, where numerous ferroelectric materials have been designed and developed to enable the advancement of diverse applications. Now the driving forces for ferroelectric studies stem from regulations on environment, human health,and sustainable society development. This leads to the resurgence of lead-free ferroelectric materials for the expectation of replacing the state-of-the-art lead- based counterparts. The next wave of explorations into ferroelectric materials may be related to the Internet-of-Things, which requires millions of self-powered sensors and memories. This will promote research on ferroelectrics for sensing, energy harvesting and storage, communication and non-volatile memories, from centimetre scale to micro and nanoscale.

Ferroelectric materials have diverse functionalities that enable numerous applications, ranging from piezoelectric sensing and dielectric energy storage to electrocaloric solid state cooling, which have attracted extensive research and development interests. As an important member of the ferroelectric family, perovskite ferroelectric materials play a key role in various kinds of modern electronic devices, such as sensors, transducers and piezoelectric actuators, while relaxor ferroelectrics and antiferroelectrics have great significance for high power and/or pulse power dielectric energy storage. Critical to environmental concerns and human health, high-performance lead-free ferroelectric materials have given rise to extensive materials research in past decades. In addition to lead-free perovskites, bismuth layer structured ferroelectrics possess good electromechanical properties and high resistivity even at temperatures above 500oC, making them candidates for high temperature piezoelectric sensing applications. Meanwhile, the recently discovered ferroelectricity in fluorite-structured oxides opens a new realm of nanoscale lead-free ferroelectrics for memory application.

Read more about this evolving area of materials research in the nearly two dozen collected papers in JMR’s Focus Issue on Lead-free Ferroelectric Materials: Piezoelectric and Dielectric Energy Storage Applications, all freely accessible until August 20, 2021.