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Structural basis for near unity quantum yield core/shell nanostructures.

James McBride·Joe Treadway·L C Feldman·Stephen J Pennycook·Sandra J Rosenthal
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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.

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Cadmium CompoundsMicroscopy, Electron, Scanning TransmissionNanostructuresQuantum DotsSulfidesZinc CompoundsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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James McBride, Joe Treadway, L C Feldman, Stephen J Pennycook, Sandra J Rosenthal. 2006. Structural basis for near unity quantum yield core/shell nanostructures.. https://doi.org/10.1021/nl060993k

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