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08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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Phonon mode transformation in size-evolved solution-processed inorganic lead halide perovskite
Huafeng Shi1, Xiaoli Zhang, Xiaowei Sun
1Department of Electrical & Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Nanoscale
|March 30, 2018
Summary
Pure inorganic lead halide perovskites in nano-cube and micro-cube forms were synthesized using a solution-processed method. Their size-dependent phonon mode transformation indicates a crystal structure phase change, ideal for optoelectronic devices.
Area of Science:
- Materials Science
- Solid State Physics
- Optoelectronics
Background:
- Lead halide perovskites are crucial for optoelectronic applications like solar cells and LEDs.
- Cubic crystal structures, including nano- and micro-cubes, offer unique optoelectronic properties.
- Colloidal synthesis provides versatility in creating these perovskite materials.
Purpose of the Study:
- To report the solution-processed synthesis of pure inorganic lead halide nano-cubes and micro-cubes.
- To investigate the relationship between cube size and crystal structure phase transitions.
- To highlight the potential of these materials for fundamental optoelectronic research and device applications.
Main Methods:
- Solution-processed colloidal synthesis of lead halide perovskites.
- Fabrication of both nano-cube and micro-cube structures.
- Phonon mode analysis to identify crystal structure phase changes.
Main Results:
- Successfully synthesized pure inorganic lead halide nano-cubes and micro-cubes.
- Demonstrated a phonon mode transformation correlating with the transition from nano-cube to micro-cube.
- Observed size-dependent crystal structure phase changes in lead halide perovskites.
Conclusions:
- The solution-processed synthesis enables control over lead halide perovskite cube size.
- Phonon mode transformation signifies a crystal structure phase change between nano- and micro-cubes.
- These size-tunable perovskite cubes are promising for advanced optoelectronic devices and fundamental studies.
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