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Grain size effects in polycrystalline gold nanoparticles.

ABSTRACT: We report a structure-property relationship in gold nanoparticles (NPs), grain-size effects, which not only allow material properties observed on different characteristic length scales to be engineered in a single NP but further enhance those properties due to the coupling among different-size grains. The grain size effects were achieved by creating polycrystalline gold NPs (pAuNPs) with two distinct grain-size populations (5 and 1 nm) comparable to electron mean free path and electron Fermi wavelength (EFW), respectively. Successful integration of molecular and plasmonic properties into a single nanostructure without additional fluorophores enables these highly polycrystalline AuNPs to serve as multimodal probes in a variety of optical microscopic imaging techniques.

SUBMITTER: Zhou C

PROVIDER: S-EPMC3389155 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Grain size effects in polycrystalline gold nanoparticles.

Zhou Chen C Yu Jing J Qin Yanping Y Zheng Jie J

Nanoscale 20120329 14

We report a structure-property relationship in gold nanoparticles (NPs), grain-size effects, which not only allow material properties observed on different characteristic length scales to be engineered in a single NP but further enhance those properties due to the coupling among different-size grains. The grain size effects were achieved by creating polycrystalline gold NPs (pAuNPs) with two distinct grain-size populations (5 and 1 nm) comparable to electron mean free path and electron Fermi wav ...[more]

PMID: 22456680

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