Synthesis of Non-blinking Semiconductor Quantum Dots Emitting in the Near-Infrared

Conference · Thu Jun 21 04:00:00 EDT 2012

OSTI ID:1044829

Dennis, Allison M ^[1]; Mangum, Benjamin D ^[1]; Piryatinski, Andrei ^[1]; Park, Young-Shin ^[1]; Htoon, Han ^[1]; Hollingsworth, Jennifer A ^[1]

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1. Los Alamos National Laboratory

Our previous work demonstrates that Quasi-Type II CdSe/CdS core-shell quantum dots with thick shells (3-5 nm) exhibit unique photophysical characteristics, including improved chemical robustness over typical thin-shelled core/shell systems and the elimination of blinking through suppression of nonradiative Auger recombination. Here we describe a new thick-shelled heterostructure, InP/CdS, which exhibits a Type II bandgap alignment producing near-infrared (NIR) emission. Samples with a range of shell thicknesses were synthesized, enabling shell-thickness-dependent study of the absorbance and emission spectra, fluorescence lifetimes, and quantum yields. InP/CdS/ZnS core/shell/shell structures were also synthesized to reduce cadmium exposure for applications in the biological environment. Single particle spectroscopy indicates reduced blinking and improved photostability with increasing shell thickness, resulting in thick-shelled dots that are appropriate for single-particle tracking measurements with NIR emission.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: LDRD
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 1044829
• Report Number(s): LA-UR-12-22429
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
ALIGNMENT
CADMIUM
EMISSION SPECTRA
FLUORESCENCE
QUANTUM DOTS
RECOMBINATION
SPECTROSCOPY
SYNTHESIS
THICKNESS