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Silver-Free Gold Nanocages with Near-Infrared Extinctions.

ABSTRACT: This article reports the preparation of silver-free Au nanocages from cubic palladium templates. Pd nanocubes were subjected to galvanic replacement with Au3+ to produce Pd@Au nanocages having tunable dimensions (i.e., edge length, gold layer thickness, and hollow pore size), which allowed selectable positioning of the optical extinction maxima from the visible to the near infrared. These new nanocages circumvent the problems associated with previous Ag-derived gold alloy nanocages, which suffer from the toxicity of residual silver and the possible fragmentation of such alloyed nanostructures, thereby limiting their potential applications. In contrast, the present materials represent stable, nontoxic, tunable, and hollow plasmonic nanostructures.

SUBMITTER: Shakiba A

PROVIDER: S-EPMC6640799 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Silver-Free Gold Nanocages with Near-Infrared Extinctions.

Shakiba Amin A Shah Shreya S Jamison Andrew C AC Rusakova Irene I Lee Tai-Chou TC Lee T Randall TR

ACS omega 20160921 3

This article reports the preparation of silver-free Au nanocages from cubic palladium templates. Pd nanocubes were subjected to galvanic replacement with Au<sup>3+</sup> to produce Pd@Au nanocages having tunable dimensions (i.e., edge length, gold layer thickness, and hollow pore size), which allowed selectable positioning of the optical extinction maxima from the visible to the near infrared. These new nanocages circumvent the problems associated with previous Ag-derived gold alloy nanocages, w ...[more]

PMID: 31457139

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