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Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
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A Lead Mixed Halide with Three Different Coordinated Anions and Strong Second-Harmonic Generation Response
Qi-Rui Shui1, Rui-Biao Fu2,1, Zi-Qi Zhou1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P. R. China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 15, 2021
Summary
A new nonlinear optical crystal, Cs3Pb2(CH3COO)2Br3I2, shows a strong second-harmonic generation (SHG) response. This discovery offers a new strategy for developing advanced NLO materials for various technological applications.
Area of Science:
- Materials Science
- Solid State Chemistry
- Crystallography
Background:
- Nonlinear optical (NLO) crystals are crucial for technologies like information processing and laser manufacturing.
- Developing NLO materials with enhanced second-harmonic generation (SHG) properties is an ongoing research challenge.
Purpose of the Study:
- To design and synthesize a novel lead mixed halide crystal with superior NLO properties.
- To investigate the structural and optical characteristics of the new material, Cs3Pb2(CH3COO)2Br3I2.
Main Methods:
- Rational design and synthesis of a new lead mixed halide compound.
- Structural characterization to understand the coordination environment around Pb(II) atoms.
- Optical property measurements, including SHG response, birefringence, and laser damage threshold (LDT).
Main Results:
- Successfully synthesized Cs3Pb2(CH3COO)2Br3I2, a rare NLO crystal with three distinct anions coordinating Pb(II).
- Observed a potent phase-matching SHG response of 9×KH2PO4 (KDP), significant birefringence (0.27@1064 nm), and a high LDT.
- Attributed the strong SHG effect to the specific arrangement of [Pb2Br3I2] chains within the crystal structure.
Conclusions:
- Cs3Pb2(CH3COO)2Br3I2 is a promising new NLO material with excellent SHG performance.
- The unique anionic coordination around Pb(II) is key to achieving high NLO activity.
- This work presents a viable strategy for discovering new NLO crystals with strong SHG capabilities.
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