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Updated: Mar 27, 2026
11:07
Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties
Published on: August 15, 2015
10.5K
Concentration- and Temperature-Induced Phase Transitions in PrAlO3-SrTiO3 System
Leonid Vasylechko1, Roman Stepchuk2, Yuri Prots3
1Lviv Polytechnic National University, 12 Bandera Street, 79013, Lviv, Ukraine. crystal-lov@polynet.lviv.ua.
Nanoscale Research Letters
|January 14, 2016
Summary
This study synthesized novel Pr1-x Sr x Al1-x Ti x O3 perovskites. Increasing Sr and Ti content significantly lowers structural transition temperatures, impacting material properties.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Perovskite oxides exhibit diverse structural and electronic properties.
- PrAlO3 undergoes a high-temperature structural phase transition.
- Tuning perovskite composition can modify transition temperatures and material behavior.
Purpose of the Study:
- To synthesize and characterize single-phase mixed aluminates-titanates Pr1-x Sr x Al1-x Ti x O3.
- To investigate the effect of strontium (Sr) and titanium (Ti) doping on the structural phase transitions.
- To understand the relationship between composition, structure, and transition temperatures.
Main Methods:
- Solid-state reaction technique at high temperatures (1823–1873 K).
- In situ high-temperature X-ray synchrotron powder diffraction.
- Analysis of morphotropic phase transitions and temperature-induced structural transformations.
Main Results:
- Single-phase Pr1-x Sr x Al1-x Ti x O3 with rhombohedral perovskite structure were successfully prepared for x = 0.1–0.7.
- A morphotropic rhombohedral-to-cubic phase transition is predicted around x = 0.88.
- The temperature-induced phase transition in Pr0.5Sr0.5Al0.5Ti0.5O3 occurs at a significantly lower temperature (930 K) compared to PrAlO3 (1770 K).
- Increasing Sr and Ti content decreases perovskite structure deformation, lowering transition temperatures due to an increased Goldschmidt tolerance factor.
- Pr0.3Sr0.7Al0.3Ti0.7O3 exhibits a sequence of low-temperature phase transformations: R3c → Imma(C2/m) → I4/mcm.
Conclusions:
- Doping PrAlO3 with Sr and Ti effectively modifies its structural phase transition temperatures.
- The observed decrease in transition temperature is attributed to reduced structural distortion and increased tolerance factor.
- The synthesized Pr1-x Sr x Al1-x Ti x O3 materials offer tunable properties for potential applications.
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