Double-crowned 2D semiconductor nanoplatelets with bicolor power-tunable emission
Corentin Dabard1, Victor Guilloux2, Charlie Gréboval2
1Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin, 75005, Paris, France.
Nature Communications
|August 30, 2022
Summary
Researchers engineered core/crown/crown 2D nanoplatelets (NPLs) for dual color emission, overcoming Kasha's rule. This breakthrough enables tunable red and green light from a single material, advancing optoelectronics and display technology.
Area of Science:
- Materials Science
- Nanotechnology
- Optoelectronics
Background:
- Nanocrystals (NCs) are key optoelectronic components, with down-conversion for displays being a major application.
- Current methods blend separate red and green NCs, causing formulation challenges.
- Kasha's rule typically dictates emission occurs at the band edge, posing challenges for dual emissions from a single source.
Purpose of the Study:
- To engineer single Nanoplatelets (NPLs) capable of dual, tunable emissions (red and green).
- To overcome Kasha's rule limitations for advanced optoelectronic applications.
- To demonstrate power-tunable dual-color emission via electrical excitation.
Main Methods:
- Fabrication of core/crown/crown 2D CdSe/CdTe/CdSe nanoplatelets (NPLs).
- Characterization of NPLs for optical properties and band alignment.
- Investigation of emission properties under varying incident power and electrical excitation.
Main Results:
- Achieved simultaneous red and narrow green emissions from single CdSe/CdTe/CdSe NPLs.
- Demonstrated type-II band alignment facilitating dual emission.
- Showcased power-dependent emission tuning due to Auger recombination saturation in red emission.
- Confirmed dual-color, power-tunable emission via electrical excitation.
Conclusions:
- Engineered NPLs successfully violate Kasha's rule, enabling dual emissions from a single material.
- The demonstrated technology offers a pathway for simplified fabrication of advanced displays.
- Power-tunable dual-color emission via electrical excitation opens new avenues for optoelectronic device design.
