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Enhancing single-nanoparticle surface-chemistry by plasmonic overheating in an optical trap.

ABSTRACT: Surface-chemistry of individual, optically trapped plasmonic nanoparticles is modified and accelerated by plasmonic overheating. Depending on the optical trapping power, gold nanorods can exhibit red shifts of their plasmon resonance (i.e., increasing aspect ratio) under oxidative conditions. In contrast, in bulk exclusively blue shifts (decreasing aspect ratios) are observed. Supported by calculations, we explain this finding by local temperatures in the trap exceeding the boiling point of the solvent that cannot be achieved in bulk.

SUBMITTER: Ni W

PROVIDER: S-EPMC3833039 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Enhancing single-nanoparticle surface-chemistry by plasmonic overheating in an optical trap.

Ni Weihai W Ba Haojin H Lutich Andrey A AA Jäckel Frank F Feldmann Jochen J

Nano letters 20120827 9

Surface-chemistry of individual, optically trapped plasmonic nanoparticles is modified and accelerated by plasmonic overheating. Depending on the optical trapping power, gold nanorods can exhibit red shifts of their plasmon resonance (i.e., increasing aspect ratio) under oxidative conditions. In contrast, in bulk exclusively blue shifts (decreasing aspect ratios) are observed. Supported by calculations, we explain this finding by local temperatures in the trap exceeding the boiling point of the ...[more]

PMID: 22924589

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