Structure Dependent Phase Stability and Thermal Expansion of Ruddlesden-Popper Strontium Titanates

Liang Feng Huang, Nathan Z. Koocher, Mingqiang Gu, James M. Rondinelli*

*Corresponding author for this work

Research output: Contribution to journalArticle

4 Scopus citations

Abstract

Ruddlesden-Popper strontium titanates with composition Srn+1TinO3n+1, RP-n-STO, n = 1, 2,⋯, ∞, are prototypical layered perovskites from which many crystal-chemistry principles can be assessed. In addition, their phase stabilities and lattice thermal expansions are essential factors for their usage in realistic devices. In this work, we use first-principles electronic structure methods to determine the n-layer dependent phase stabilities, including thermodynamic energies and pressure-critical temperature (P-Tc) phase diagrams and coefficients of thermal expansion. We correlate these properties with the perovskite (SrTiO3)n·SrO block thickness, n, to show that a change in materials behavior occurs at a critical thickness nc = 3, which we ascribe to the presence (absence) of octahedral layers exhibiting antiferrodistortions at n ≥ 3 (n < 3). Last, we attribute the absence of quasi-two-dimensional lattice anharmonicity in the layered RP titanates to the stiff (SrTiO3)n intrablock Ti-O bonds and strong interblock bonding. The layer dependent properties studied here will be useful for the design and application of related quasi-2D materials and devices.

Original languageEnglish (US)
Pages (from-to)7100-7110
Number of pages11
JournalChemistry of Materials
Volume30
Issue number20
DOIs
StatePublished - Oct 23 2018

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Structure Dependent Phase Stability and Thermal Expansion of Ruddlesden-Popper Strontium Titanates'. Together they form a unique fingerprint.

  • Cite this