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Melting and Sintering of a Body-Centered Cubic Superlattice of PbSe Nanocrystals Followed by Small Angle X-ray Scattering.

ABSTRACT: The structural evolution of a body-centered cubic (bcc) superlattice of 6.6 nm diameter organic ligand-coated PbSe nanocrystals was studied in situ by small angle X-ray scattering (SAXS) as it was heated in air from room temperature to 350°C. As it was heated above room temperature, the superlattice contracted slightly, but maintained bcc structure up to 110°C. Once the temperature rose above 110°C, the superlattice began to disorder, by first losing long-range translational order and then local positional order. At temperatures exceeding 168°C, the nanocrystals sintered and oxidized, transforming into PbSeO(3) nanorods.

SUBMITTER: Goodfellow BW

PROVIDER: S-EPMC3090084 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Melting and Sintering of a Body-Centered Cubic Superlattice of PbSe Nanocrystals Followed by Small Angle X-ray Scattering.

Goodfellow Brian W BW Patel Reken N RN Panthani Matthew G MG Smilgies Detlef-M DM Korgel Brian A BA

The journal of physical chemistry. C, Nanomaterials and interfaces 20110401 14

The structural evolution of a body-centered cubic (bcc) superlattice of 6.6 nm diameter organic ligand-coated PbSe nanocrystals was studied in situ by small angle X-ray scattering (SAXS) as it was heated in air from room temperature to 350°C. As it was heated above room temperature, the superlattice contracted slightly, but maintained bcc structure up to 110°C. Once the temperature rose above 110°C, the superlattice began to disorder, by first losing long-range translational order and then local ...[more]

PMID: 21566701

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