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Title: Structural Basis for Near Unity Quantum Yield Core/Shell Nanostructures

Abstract

Aberration-corrected Z-contrast scanning transmission electron microscopy of core/shell nanocrystals shows clear correlations between structure and quantum efficiency. Uniform shell coverage is obtained only for a graded CdS/ZnS shell material and is found to be critical to achieving near 100% quantum yield. The sublattice sensitivity of the images confirms that preferential growth takes place on the anion-terminated surfaces. This explains the three-dimensional "nanobullet" shape observed in the case of core/shell nanorods.

Authors:
 [1];  [2];  [3];  [3]
  1. Vanderbilt University
  2. Quantum Dot Corporation, Hayward, California
  3. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
930774
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters; Journal Volume: 6; Journal Issue: 7
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; MONOCRYSTALS; NANOSTRUCTURES; QUANTUM EFFICIENCY; TRANSMISSION ELECTRON MICROSCOPY; SCANNING ELECTRON MICROSCOPY; CADMIUM SULFIDES; ZINC SULFIDES; Structural; Quantum; nanostructures

Citation Formats

McBride, James, Treadway, Joe, Pennycook, Stephen J, and Rosenthal, Sandra. Structural Basis for Near Unity Quantum Yield Core/Shell Nanostructures. United States: N. p., 2006. Web. doi:10.1021/nl060993k.
McBride, James, Treadway, Joe, Pennycook, Stephen J, & Rosenthal, Sandra. Structural Basis for Near Unity Quantum Yield Core/Shell Nanostructures. United States. doi:10.1021/nl060993k.
McBride, James, Treadway, Joe, Pennycook, Stephen J, and Rosenthal, Sandra. Sun . "Structural Basis for Near Unity Quantum Yield Core/Shell Nanostructures". United States. doi:10.1021/nl060993k.
@article{osti_930774,
title = {Structural Basis for Near Unity Quantum Yield Core/Shell Nanostructures},
author = {McBride, James and Treadway, Joe and Pennycook, Stephen J and Rosenthal, Sandra},
abstractNote = {Aberration-corrected Z-contrast scanning transmission electron microscopy of core/shell nanocrystals shows clear correlations between structure and quantum efficiency. Uniform shell coverage is obtained only for a graded CdS/ZnS shell material and is found to be critical to achieving near 100% quantum yield. The sublattice sensitivity of the images confirms that preferential growth takes place on the anion-terminated surfaces. This explains the three-dimensional "nanobullet" shape observed in the case of core/shell nanorods.},
doi = {10.1021/nl060993k},
journal = {Nano Letters},
number = 7,
volume = 6,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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