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Self-Assembly and Thermal Stability of Binary Superlattices of Gold and Silicon Nanocrystals.

ABSTRACT: Simple hexagonal (sh) AB2 binary superlattices (BSLs) of organic ligand-capped silicon (A; 5.40(±9.8%) nm diameter) and gold (B; 1.88(±10.1%) nm diameter) nanocrystals were assembled by evaporation of colloidal dispersions and characterized using transmission electron microscopy (TEM) and grazing incidence small-angle X-ray scattering (GISAXS). When deposited on tilted substrates by slow evaporation, the sh-AB2 superlattice contracts slightly towards the substrate with centered orthorhombic structure. Heating the BSL to 200°C in air led to gold coalescence and segregation to the surface of the assembly without disrupting the Si nanocrystal sublattice, thus creating a simple hexagonal superlattice of Si nanocrystals.

SUBMITTER: Yu Y

PROVIDER: S-EPMC3855828 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Self-Assembly and Thermal Stability of Binary Superlattices of Gold and Silicon Nanocrystals.

Yu Yixuan Y Bosoy Christian A CA Smilgies Detlef-M DM Korgel Brian A BA

The journal of physical chemistry letters 20131001 21

Simple hexagonal (sh) AB<sub>2</sub> binary superlattices (BSLs) of organic ligand-capped silicon (A; 5.40(±9.8%) nm diameter) and gold (B; 1.88(±10.1%) nm diameter) nanocrystals were assembled by evaporation of colloidal dispersions and characterized using transmission electron microscopy (TEM) and grazing incidence small-angle X-ray scattering (GISAXS). When deposited on tilted substrates by slow evaporation, the sh-AB<sub>2</sub> superlattice contracts slightly towards the substrate with cent ...[more]

PMID: 24327828

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