Perovskite ferroelectrics go metal-free

Abstract

Ferroelectric materials do something unique under an applied electric field: They exhibit spontaneous polarization, meaning positive and negative charges quickly separate within the crystal. That property makes the materials ideal for numerous applications in energy storage, medical imaging, and computer memory that retains information even when a device is off. By supplementing a design strategy with trial-and-error experimentation, researchers have now discovered a new family of metal-free ferroelectric materials. The finding may pave the way to lightweight, flexible, and low-cost memory devices, capacitors, and other types of electronics (Science 2018, DOI: 10.1126/science.aas9330). Common ferroelectrics currently used in devices include barium titanate (BaTiO3 or BTO), lead titanate, and other ceramics with the perovskite structure and composition, which follows the stoichiometry ABX3. Although widely used industrially, these materials are costly to produce and often contain lead and other toxic heavy...