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Updated: Jun 11, 2026
10:40
A Fabrication and Measurement Method for a Flexible Ferroelectric Element Based on Van Der Waals Heteroepitaxy
Published on: April 8, 2018
8.2K
Switchable Photovoltaic Effect and Robust Nonlinear Optical Response in a High-Temperature Molecular Ferroelectric
Zhibo Chen1, Ganghua Zhang1, Jinrong Wen1
1School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418, P. R. China.
Inorganic Chemistry
|October 20, 2024
Summary
We developed a new lead halide molecular ferroelectric material with room-temperature ferroelectricity and a direct band gap. This material shows promising photovoltaic effects and enhanced performance, making it suitable for optoelectronic devices.
Area of Science:
- Materials Science
- Solid-State Physics
- Crystallography
Background:
- Hybrid organic-inorganic molecular ferroelectrics (HOIMFs) are explored for memory and spintronics.
- Photoelectric properties of lead halide molecular ferroelectrics remain underexplored despite their potential for flexible thin-film devices.
Purpose of the Study:
- To synthesize and characterize a novel lead halide molecular ferroelectric with potential photoelectric applications.
- To investigate the ferroelectric, photoelectric, and second-harmonic generation (SHG) properties of the new material.
Main Methods:
- Hydrothermal synthesis of [C8N2H22][PbI4] (1).
- Single-crystal X-ray diffraction and second-harmonic generation (SHG) tests for structural analysis.
- UV-vis spectroscopy and theoretical calculations for band gap determination.
- Hysteresis measurements for ferroelectric properties and device fabrication for photovoltaic testing.
Main Results:
- A polar monoclinic structure was confirmed for [C8N2H22][PbI4] (1).
- A direct band gap of 2.36 eV and room-temperature ferroelectricity with a spontaneous polarization of 3.2 μC/cm² were observed.
- The material exhibited a photovoltaic effect with rapid response times and tunable performance, alongside a significant SHG signal (2.61-fold higher than KDP).
Conclusions:
- The novel lead halide molecular ferroelectric [C8N2H22][PbI4] (1) demonstrates promising room-temperature ferroelectricity and photoelectric properties.
- The material's tunable photovoltaic performance and strong SHG signal position it as a potential candidate for advanced optoelectronic devices and nonlinear optics.
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