Phonon scattering mechanisms dictating the thermal conductivity of lead zirconate titanate (PbZr1-xTixO3) thin films across the compositional phase diagram

Foley, Brian M.; Paisley, Elizabeth A.; DiAntonio, Christopher; Chavez, Tom; Blea-Kirby, Mia; Brennecka, Geoff; Gaskins, John T.; Ihlefeld, Jon F.; Hopkins, Patrick E.

doi:10.1063/1.4983356

Phonon scattering mechanisms dictating the thermal conductivity of lead zirconate titanate (PbZr_1-_xTi_xO₃) thin films across the compositional phase diagram

Journal Article · Tue May 23 00:00:00 EDT 2017 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4983356· OSTI ID:1372309

Foley, Brian M. ^[1]; Paisley, Elizabeth A. ^[2]; DiAntonio, Christopher ^[2]; Chavez, Tom ^[2]; Blea-Kirby, Mia ^[2]; ^[3]; Gaskins, John T. ^[1]; Ihlefeld, Jon F. ^[2]; Hopkins, Patrick E. ^[1]

Univ. of Virginia, Charlottesville, VA (United States). Dept. of Mechanical and Aerospace Engineering
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgical and Materials Engineering

This paper represents a thorough investigation of the thermal conductivity (κ) in both thin film and bulk PbZr_1–xTi_xO₃ (PZT) across the compositional phase diagram. Given the technological importance of PZT as a superb piezoelectric and ferroelectric material in devices and systems impacting a wide array of industries, this research serves to fill the gap in knowledge regarding the thermal properties. The thermal conductivities of both thin film and bulk PZT are found to vary by a considerable margin as a function of composition x. Additionally, we observe a discontinuity in κ in the vicinity of the morphotropic phase boundary (MPB, x = 0.48) where there is a 20%–25% decrease in κ in our thin film data, similar to that found in literature data for bulk PZT. The comparison between bulk and thin film materials highlights the sensitivity of κ to size effects such as film thickness and grain size even in disordered alloy/solid-solution materials. A model for the thermal conductivity of PZT as a function of composition (κ(x)) is presented, which enables the application of the virtual crystal approximation for alloy-type material systems with very different crystals structures, resulting in differing temperature trends for κ. We show that in the case of crystalline solid-solutions where the thermal conductivity of one of the parent materials exhibits glass-like temperature trends the compositional dependence of thermal conductivity is relatively constant for most values of x. Finally, this is in stark contrast with the typical trends of thermal conductivity with x in alloys, where the thermal conductivity increases dramatically as the composition of the alloy or solid-solution approaches that of a pure parent materials (i.e., as x = 0 or 1).

View Accepted Manuscript (DOE)

Research Organization:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Univ. of Virginia, Charlottesville, VA (United States)

Sponsoring Organization:: USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA); Air Force Office of Scientific Research (AFOSR) (United States)

Contributing Organization:: Colorado School of Mines, Golden, CO (United States)

Grant/Contract Number:: AC04-94AL85000

OSTI ID:: 1372309

Report Number(s):: SAND2017--7366J; 655303

Journal Information:: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 20 Vol. 121; ISSN 0021-8979

Publisher:: American Institute of Physics (AIP)Copyright Statement

Country of Publication:: United States

Language:: English

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