Dielectric and Pyroelectric Properties of Sodium Niobate Ceramics Containing Inclusions of Ferroelectric Q Phase

Abstract

For sodium niobate (NaNbO 3 ) ceramics containing in the nonpoled state about 30% of the ferroelectric Q phase, the temperature dependences of the dielectric constant ε and pyroelectric coefficient p are studied. The results obtained show that the transition from the Q phase into the high-temperature nonpolar phase seems to be a diffuse one and the remanent polarization remains nonzero up to %370 C, i.e., well above the temperature of the p(T ) maximum (%270 C). Poled NaNbO 3 ceramics possess high figures of merit for pyroelectric sensors and NaNbO 3 -based materials are prospective for application in the noncooled infrared detectors.

Design of Lead-Free Antiferroelectric (1 – x)NaNbO3–xSrSnO3 Compositions Guided by First-Principles Calculations

“…The dielectric properties of the investigated materials are shown in Figure . The temperature of maximum permittivity at ∼370 °C represents the phase transition from the P to R phase , in NaNbO 3 . This transition temperature is lower in the investigated SrSnO 3 -modified compositions and follows a linear decrease with increasing SrSnO 3 content at a slope of −26.3 ± 0.4 °C/mol %.…”

On the coexistence of ferroelectric and antiferroelectric polymorphs in NaNbO3 fibers at room temperature

“…Contemporary society has experienced technological development that has led research to focus on materials that have and combine functional properties. Sodium niobate (NaNbO 3 ) is a multifunctional perovskite-structured material with interesting properties 1–6 and shows a complex structural phase transition as a function of pressure, temperature, and particle size. 7–9…”