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Understanding metal-enhanced fluorescence and structural properties in Au@Ag core-shell nanocubes.

ABSTRACT: Au@Ag core-shell structures have received particular interest due to their localized surface plasmon resonance properties and great potential as oxygen reduction reaction catalysts and building blocks for self-assembly. In this study, Au@Ag core-shell nanocubes (Au@AgNCs) were fabricated in a facile manner via stepwise Ag reduction on Au nanoparticles (AuNPs). The size of the Au@AgNCs and their optical properties can be simply modulated by changing the Ag shell thickness. Structural characterization has been carried out by TEM, SAED, and XRD. The metal-induced fluorescence properties of probe molecules near the Au@AgNCs were measured during sedimentation of the Au@AgNCs. The unique ring-like building block of Au@AgNCs has dual optical functions as a fluorescence quencher or fluorescence enhancement medium depending on the assembled regions.

SUBMITTER: Jung DW

PROVIDER: S-EPMC9071844 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Understanding metal-enhanced fluorescence and structural properties in Au@Ag core-shell nanocubes.

Jung Dae-Woong DW Kim Jun Min JM Yun Hyung Joong HJ Yi Gi-Ra GR Cho Jung Young JY Jung Haeun H Lee Gaehang G Chae Weon-Sik WS Nam Ki Min KM

RSC advances 20190917 50

Au@Ag core-shell structures have received particular interest due to their localized surface plasmon resonance properties and great potential as oxygen reduction reaction catalysts and building blocks for self-assembly. In this study, Au@Ag core-shell nanocubes (Au@AgNCs) were fabricated in a facile manner <i>via</i> stepwise Ag reduction on Au nanoparticles (AuNPs). The size of the Au@AgNCs and their optical properties can be simply modulated by changing the Ag shell thickness. Structural chara ...[more]

PMID: 35528395

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