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Title: Shaping Binary Metal Nanocrystals through Epitaxial SeededGrowth

Abstract

Morphological control of nanocrystals has become increasingly important, as many of their physical and chemical properties are highly shape dependent. Nanocrystal shape control for both single- and multiple-material systems, however, remains empirical and challenging. New methods need to be explored for the rational synthetic design of heterostructures with controlled morphology. Overgrowth of a different material on well-faceted seeds, for example, allows for the use of the defined seed morphology to control nucleation and growth of the secondary structure. Here, we have used highly faceted cubic Pt seeds to direct the epitaxial overgrowth of a secondary metal. We demonstrate this concept with lattice-matched Pd to produce conformal shape-controlled core-shell particles, and then extend it to lattice-mismatched Au to give anisotropic growth. Seeding with faceted nanocrystals may have significant potential towards the development of shape-controlled heterostructures with defined interfaces.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director, Office of Science
OSTI Identifier:
928341
Report Number(s):
LBNL-63626
TRN: US200815%%750
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Materials; Journal Volume: 6; Journal Issue: 9; Related Information: Journal Publication Date: 2007
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; PROCESS CONTROL; MORPHOLOGY; NUCLEATION; SHAPE; MONOCRYSTALS; NANOSTRUCTURES; PLATINUM; EPITAXY; PALLADIUM; GOLD

Citation Formats

Habas, Susan E., Lee, Hyunjoo, Radmilovic, Velimir, Somorjai,Gabor A., and Yang, Peidong. Shaping Binary Metal Nanocrystals through Epitaxial SeededGrowth. United States: N. p., 2007. Web. doi:10.1038/nmat1957.
Habas, Susan E., Lee, Hyunjoo, Radmilovic, Velimir, Somorjai,Gabor A., & Yang, Peidong. Shaping Binary Metal Nanocrystals through Epitaxial SeededGrowth. United States. doi:10.1038/nmat1957.
Habas, Susan E., Lee, Hyunjoo, Radmilovic, Velimir, Somorjai,Gabor A., and Yang, Peidong. Sun . "Shaping Binary Metal Nanocrystals through Epitaxial SeededGrowth". United States. doi:10.1038/nmat1957.
@article{osti_928341,
title = {Shaping Binary Metal Nanocrystals through Epitaxial SeededGrowth},
author = {Habas, Susan E. and Lee, Hyunjoo and Radmilovic, Velimir and Somorjai,Gabor A. and Yang, Peidong},
abstractNote = {Morphological control of nanocrystals has become increasingly important, as many of their physical and chemical properties are highly shape dependent. Nanocrystal shape control for both single- and multiple-material systems, however, remains empirical and challenging. New methods need to be explored for the rational synthetic design of heterostructures with controlled morphology. Overgrowth of a different material on well-faceted seeds, for example, allows for the use of the defined seed morphology to control nucleation and growth of the secondary structure. Here, we have used highly faceted cubic Pt seeds to direct the epitaxial overgrowth of a secondary metal. We demonstrate this concept with lattice-matched Pd to produce conformal shape-controlled core-shell particles, and then extend it to lattice-mismatched Au to give anisotropic growth. Seeding with faceted nanocrystals may have significant potential towards the development of shape-controlled heterostructures with defined interfaces.},
doi = {10.1038/nmat1957},
journal = {Nature Materials},
number = 9,
volume = 6,
place = {United States},
year = {Sun Apr 22 00:00:00 EDT 2007},
month = {Sun Apr 22 00:00:00 EDT 2007}
}
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