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Title: Self-Assembled Colloidal Crystals from ZrO 2 Nanoparticles

Abstract

Ordered three-dimensional (3-D) assemblies of nanocrystalline zirconia were synthesized from aqueous suspensions of ZrO{sub 2} nanoparticles without the need for hydrocarbon surfactants or solvents to control colloidal crystal growth. Nanoparticles were suspended in mild acid and subsequently titrated from low to neutral pH. The solubility was reduced as the surfaces were neutralized, promoting assembly of the nanoparticles into ordered monoliths. TEM measurements indicated the formation of three-dimensional, hexagonal faceted, micrometer-sized colloidal crystals composed of 4 nm diameter ZrO{sub 2} nanoparticles. Lacking organic surfactants, the colloidal crystals were exceptionally robust and were sintered at high temperatures (300-500 C) for further stability. Small-angle X-ray scattering (SAXS) measurements demonstrate that the samples become progressively more amorphous above 350 C, although some ordered domains of nanoparticles persist. Additionally, the heat treatment dramatically increases the surface area of the colloidal crystals as water and residual organics are desorbed, revealing highly controlled interstitial spaces and pores.

Authors:
 [1];  [1];  [2];  [1];  [1]
  1. ORNL
  2. {Larry} M [ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Nanophase Materials Sciences; High Temperature Materials Laboratory
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1003545
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry B; Journal Volume: 110; Journal Issue: 39
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CRYSTAL GROWTH; HEAT TREATMENTS; HYDROCARBONS; INTERSTITIALS; SCATTERING; SOLUBILITY; SOLVENTS; STABILITY; SURFACE AREA; SURFACTANTS; WATER

Citation Formats

Woodward, Jonathan, Pickel, Joseph M, Anovitz, Lawrence, Heller, William T, and Rondinone, Adam Justin. Self-Assembled Colloidal Crystals from ZrO2 Nanoparticles. United States: N. p., 2006. Web. doi:10.1021/jp062471z.
Woodward, Jonathan, Pickel, Joseph M, Anovitz, Lawrence, Heller, William T, & Rondinone, Adam Justin. Self-Assembled Colloidal Crystals from ZrO2 Nanoparticles. United States. doi:10.1021/jp062471z.
Woodward, Jonathan, Pickel, Joseph M, Anovitz, Lawrence, Heller, William T, and Rondinone, Adam Justin. Sun . "Self-Assembled Colloidal Crystals from ZrO2 Nanoparticles". United States. doi:10.1021/jp062471z.
@article{osti_1003545,
title = {Self-Assembled Colloidal Crystals from ZrO2 Nanoparticles},
author = {Woodward, Jonathan and Pickel, Joseph M and Anovitz, Lawrence and Heller, William T and Rondinone, Adam Justin},
abstractNote = {Ordered three-dimensional (3-D) assemblies of nanocrystalline zirconia were synthesized from aqueous suspensions of ZrO{sub 2} nanoparticles without the need for hydrocarbon surfactants or solvents to control colloidal crystal growth. Nanoparticles were suspended in mild acid and subsequently titrated from low to neutral pH. The solubility was reduced as the surfaces were neutralized, promoting assembly of the nanoparticles into ordered monoliths. TEM measurements indicated the formation of three-dimensional, hexagonal faceted, micrometer-sized colloidal crystals composed of 4 nm diameter ZrO{sub 2} nanoparticles. Lacking organic surfactants, the colloidal crystals were exceptionally robust and were sintered at high temperatures (300-500 C) for further stability. Small-angle X-ray scattering (SAXS) measurements demonstrate that the samples become progressively more amorphous above 350 C, although some ordered domains of nanoparticles persist. Additionally, the heat treatment dramatically increases the surface area of the colloidal crystals as water and residual organics are desorbed, revealing highly controlled interstitial spaces and pores.},
doi = {10.1021/jp062471z},
journal = {Journal of Physical Chemistry B},
number = 39,
volume = 110,
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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