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Updated: Sep 24, 2025
08:00
Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
11.2K
High-temperature ferroelastic phase transition in a perovskite-like complex: [Et4N]2[PbBr3]2
Yuan Huang1, Jie Yang1, Zi-Jian Li2
1College of Pharmacy, Jiangxi University of Traditional Chinese Medicine Nanchang 330004 P. R. China qk0876@hotmail.com.
RSC Advances
|May 6, 2022
Summary
A novel hybrid organic-inorganic complex exhibits reversible structural phase transitions and switchable dielectric properties, making it a potential temperature-switchable molecular dielectric material for ferroic applications.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Hybrid organic-inorganic materials offer tunable properties for advanced applications.
- Perovskite-like structures are of interest due to their diverse functionalities.
- Ferroelastic materials exhibit reversible structural changes under stress.
Purpose of the Study:
- To synthesize and characterize a new lead-bromide hybrid organic-inorganic complex.
- To investigate its structural phase transition and dielectric properties.
- To explore its potential as a molecular dielectric material.
Main Methods:
- Synthesis of [Et4N]2[PbBr3]2 complex.
- X-ray structure determination at variable temperatures.
- Differential scanning calorimetry and dielectric measurements.
- Atomic-force microscopy for ferroelastic domain wall observation.
Main Results:
- The complex crystallizes in a distorted perovskite-like structure.
- A reversible structural phase transition occurs around 370 K, associated with a step-like dielectric anomaly.
- Switchable dielectric behavior is linked to cation motion and ion displacement.
- Ferroelastic domain walls were visualized.
Conclusions:
- The synthesized complex exhibits ferroelasticity and switchable dielectric properties.
- Its reversible structural phase transition makes it a promising candidate for temperature-switchable molecular dielectric applications.
- This study contributes to the development of novel functional materials in the ferroic field.
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