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Synthesis of In37P20O2CR51 Clusters and Their Conversion to InP Quantum Dots
Published on: May 7, 2019
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Mapping the reaction zones for CdTe magic-sized clusters and their emission properties
Saryvoudh A Mech1, Fuyan Ma1, Chenjie Zeng1
1Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA. zeng@chem.ufl.edu.
Nanoscale
|December 12, 2022
Summary
CdTe magic-sized clusters (MSCs) synthesis was optimized by mapping reaction zones. Specific conditions using toluene solvent and excess trioctylphosphine telluride (TOPTe) yield pure 449 nm CdTe MSCs.
Area of Science:
- Materials Science
- Nanotechnology
- Chemical Synthesis
Background:
- CdTe magic-sized clusters (MSCs) offer unique properties for semiconductor devices.
- Varied synthetic conditions hinder understanding of CdTe MSC formation mechanisms.
Purpose of the Study:
- To systematically investigate reaction parameters influencing CdTe MSC formation.
- To map reaction zones for reproducible synthesis of CdTe MSCs and quantum dots (QDs).
Main Methods:
- Employed standard precursors: Cd(oleate)2, trioctylphosphine telluride (TOPTe), and oleylamine.
- Varied solvent, phosphine/oleylamine amounts, Cd:Te ratio, and temperature.
- Analyzed the evolution of MSCs and QDs over time.
Main Results:
- High-purity 449 nm CdTe MSCs synthesized using excess TOPTe in toluene at 100 °C.
- Higher temperatures, excess Cd(oleate)2, or viscous solvents led to larger MSCs (469 nm) and QDs (>500 nm).
- Increased phosphine enhanced yield; oleylamine was critical for MSC formation.
Conclusions:
- Mapping reaction zones provides a pathway for rational synthesis of CdTe MSCs.
- Understanding these zones is key to elucidating CdTe MSC formation mechanisms.
- Non-emissive 449 nm MSCs showed emission when mixed with QDs, attributed to QD formation.
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