Piezoelectricity enhancement in Dion-Jacobson RbBiNb2O7 via negative pressure
1 Frontier Institute of Science and Technology, and State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University - Xi’ an 710049, PRC
2 MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xian Jiaotong University - Xian 710049, PRC
Received: 23 October 2014
Accepted: 5 December 2014
We use first-principles calculations to study the structural, ferroelectric and piezoelectric properties of the recently synthesized Dion-Jacobson RbBiNb2O7, a novel layered-perovskite piezoelectrics with extremely high Curie temperature TC. We show that ferroelectric RbBiNb2O7 crystalizes in orthorhombic Pmc21 phase, exhibiting in-plane spontaneous polarization. We well reproduce the major experimental results for RbBiNb2O7. We further propose that under 5% volume-expansion–induced negative pressure, increase of dielectric permittivity and increase of piezoelectricity can be achieved in RbBiNb2O7. The decomposed piezoelectricity analysis reveals that the activation of piezoelectric response of cation Rb by negative pressure can lead to large piezoelectricity enhancement. Based on our calculations, we demonstrate that negative pressure is a promising way to optimize the performance of RbBiNb2O7 as high-TC piezoelectrics.
PACS: 77.84.-s – Dielectric, piezoelectric, ferroelectric, and antiferroelectric materials / 61.50.Ah – Theory of crystal structure, crystal symmetry; calculations and modeling / 71.15.Mb – Density functional theory, local density approximation, gradient and other corrections
© EPLA, 2014