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Title: Elastic properties of close-packed, free-standing nanoparticle arrays.

Abstract

Nanoparticle superlattices are hybrid materials composed of close-packed inorganic particles separated by short organic spacers. Most work so far has concentrated on the unique electronic, optical and magnetic behavior of these systems. Here, we demonstrate that they also possess remarkable mechanical properties. We focus on two-dimensional arrays of close-packed nanoparticles and show that they can be stretched across micrometer-size holes. The resulting free-standing monolayer membranes extend over hundreds of particle diameters without crosslinking of the ligands or further embedding in polymer. To characterize the membranes we measured elastic properties with force microscopy and determined the array structure using transmission electron microscopy. For dodecanethiol-ligated 6-nm-diameter gold nanocrystal monolayers, we find a Young's modulus of the order of several GPa. This remarkable strength is coupled with high flexibility, enabling the membranes to bend easily while draping over edges. The arrays remain intact and able to withstand tensile stresses up to temperatures around 370 K. The purely elastic response of these ultrathin membranes, coupled with exceptional robustness and resilience at high temperatures should make them excellent candidates for a wide range of sensor applications.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
UC-ANL Consotium for Nanoscience Research; NSR-MRSEC; MRSEC REU
OSTI Identifier:
958535
Report Number(s):
ANL/CNM/JA-59573
TRN: US201001%%423
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Mater.; Journal Volume: 6; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; 36 MATERIALS SCIENCE; NANOSTRUCTURES; ELASTICITY; FLEXIBILITY; GOLD; MECHANICAL PROPERTIES; MEMBRANES; SUPERLATTICES; YOUNG MODULUS; TENSILE PROPERTIES

Citation Formats

Mueggenburg, K. E., Lin, X.-M., Goldsmith, R. H., Jaeger, H. M., Center for Nanoscale Materials, and Univ. of Chicago. Elastic properties of close-packed, free-standing nanoparticle arrays.. United States: N. p., 2007. Web. doi:10.1038/nmat1965.
Mueggenburg, K. E., Lin, X.-M., Goldsmith, R. H., Jaeger, H. M., Center for Nanoscale Materials, & Univ. of Chicago. Elastic properties of close-packed, free-standing nanoparticle arrays.. United States. doi:10.1038/nmat1965.
Mueggenburg, K. E., Lin, X.-M., Goldsmith, R. H., Jaeger, H. M., Center for Nanoscale Materials, and Univ. of Chicago. Mon . "Elastic properties of close-packed, free-standing nanoparticle arrays.". United States. doi:10.1038/nmat1965.
@article{osti_958535,
title = {Elastic properties of close-packed, free-standing nanoparticle arrays.},
author = {Mueggenburg, K. E. and Lin, X.-M. and Goldsmith, R. H. and Jaeger, H. M. and Center for Nanoscale Materials and Univ. of Chicago},
abstractNote = {Nanoparticle superlattices are hybrid materials composed of close-packed inorganic particles separated by short organic spacers. Most work so far has concentrated on the unique electronic, optical and magnetic behavior of these systems. Here, we demonstrate that they also possess remarkable mechanical properties. We focus on two-dimensional arrays of close-packed nanoparticles and show that they can be stretched across micrometer-size holes. The resulting free-standing monolayer membranes extend over hundreds of particle diameters without crosslinking of the ligands or further embedding in polymer. To characterize the membranes we measured elastic properties with force microscopy and determined the array structure using transmission electron microscopy. For dodecanethiol-ligated 6-nm-diameter gold nanocrystal monolayers, we find a Young's modulus of the order of several GPa. This remarkable strength is coupled with high flexibility, enabling the membranes to bend easily while draping over edges. The arrays remain intact and able to withstand tensile stresses up to temperatures around 370 K. The purely elastic response of these ultrathin membranes, coupled with exceptional robustness and resilience at high temperatures should make them excellent candidates for a wide range of sensor applications.},
doi = {10.1038/nmat1965},
journal = {Nature Mater.},
number = 2007,
volume = 6,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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