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Updated: Sep 18, 2025
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
9.7K
Cu-Induced Phase Transitions and Energy Bandgap Tuning in 2D Ruddlesden-Popper Perovskites
Shambhavi J Joshi1, Nilesh G Saykar2, Kusuma Jagadish2
1Department of Physics, Manipal Institute of Technology Bengaluru, Manipal Academy of Higher Education, Manipal 576104, India.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 25, 2025
Summary
Researchers developed lead-reduced 2D perovskites by substituting copper for lead, creating environmentally friendly materials. These novel perovskites show tunable bandgaps for optoelectronics and potential in thermochromic and ferroelectric applications.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Optoelectronics
Background:
- Ruddlesden-Popper perovskites are promising for optoelectronics but contain toxic lead.
- Lead toxicity and material stability hinder the development of lead-based perovskites.
Purpose of the Study:
- To develop lead-reduced 2D perovskite alternatives using transition-metal substitution.
- To investigate the structural, optical, and thermal properties of copper-lead mixed perovskites.
Main Methods:
- Synthesis of (BA)2PbxCu1-xCl4 2D perovskites.
- Powder X-ray diffraction for structural characterization.
- Temperature-dependent X-ray diffraction and photoluminescence spectroscopy.
Main Results:
- Successful incorporation of Cu2+ into the perovskite lattice confirmed.
- Tunable optical energy bandgaps achieved from 3.55 to 2.27 eV.
- Reversible structural phase transitions observed around 200 K in Cu-Pb mixed perovskites, linked to octahedral tilting and Jahn-Teller distortions.
Conclusions:
- Copper-lead mixed perovskites offer an environmentally friendly alternative to lead-based materials.
- Tunable bandgaps make these materials suitable for next-generation optoelectronic devices.
- Potential applications in thermochromic and ferroelectric technologies were highlighted.
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