Phase Switching as the Origin of Large Piezoelectric Response in Organic-Inorganic Perovskites: A First-Principles Study

Journal Article · Wed Nov 11 00:00:00 EST 2020 · Physical Review Letters

DOI:https://doi.org/10.1103/physrevlett.125.207601· OSTI ID:1712745

Ghosh, P. S. ^[1]; Lisenkov, Sergey ^[2]; Ponomareva, Inna ^[2]

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1. Univ. of South Florida, Tampa, FL (United States); Bhabha Atomic Research Centre, Mumbai (India); University of South Florida
2. Univ. of South Florida, Tampa, FL (United States)

Piezoelectrics are critical functional components of many practical applications such as sensors, ultrasonic transducers, actuators, medical imaging, telecommunications. So far, the best performing piezoelectrics are ferroelectric ceramics, many of which are toxic, heavy, hard, and cost-ineffective. Recently, a groundbreaking discovery of extraordinarily large piezoelectric coefficients in the family of organic-inorganic perovskites gave a hope for a cheaper, environmentally friendly, inexpensive, light-weight and flexible alternative. However, the origin of such response in organic-inorganic ferroelectrics whose spontaneous polarization is an order of magnitude smaller than for inorganic counterparts remains unclear. In this study we employ first-principles simulations to predict that the mechanism associated with large piezoelectric constants is of extrinsic origin and associated with switching between the stable phase and previously overlooked energetically competitive metastable phase that can be stabilized by the external stress. Here, the phase switching changes the polarization direction and, therefore, gives origin to large piezoelectric response, similar to PbZr$$_{1-x}$$Ti$$_x$$O$$_3$$ near morphotropic phase boundary. Existence of such metastable phases is likely to manifest as the dynamical molecular disorder above the Curie temperature and, therefore, could be intrinsic to the entire family of organic-inorganic ferroelectrics with such disorder.

• Research Organization: Univ. of South Florida, Tampa, FL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
• Grant/Contract Number: SC0005245
• OSTI ID: 1712745
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 20 Vol. 125; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DFT simulations
density functional theory
first-principles calculations
hybrid organic-inorganic perovskites
phase transitions
piezoelectric effect
piezoelectricity
piezoelectrics