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Designing caps for colloidal Au nanoparticles.

ABSTRACT: The plasmonic property of a nanostructure is highly dependent on its morphology, but there are few methods for appending a domain as the "functional group" or modifier. As a means of modulating plasmonic properties, we create and modulate Au hats on Au nanoparticles, including mortarboards, beret hats, helmets, crowns, antler hats and antenna hats. The structural control arises from the active surface growth as a result of dynamic competition between ligand absorption and metal deposition. It allows the continuous tuning of hat morphologies, from the facet-controlled growth of mortarboards, to the spreading-favored growth of beret hats and helmets, and to the vertical growth of pillars in crowns, antler hats and antenna hats. Among these plasmonic nanostructures, the mortarboards show excellent SERS enhancement of 8.1 × 10⁵, which is among the best in colloidal nanostructures; and the antler hats show the photothermal conversion efficiency of 66.2%, which compares favorably with the literature reports.

SUBMITTER: Tian X

PROVIDER: S-EPMC8179445 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Designing caps for colloidal Au nanoparticles.

Tian Xiaoli X Zong Jianpeng J Zhou Yusai Y Chen Dapeng D Jia Jia J Li Shuaibin S Dong Xiaochen X Feng Yuhua Y Chen Hongyu H

Chemical science 20210120 10

The plasmonic property of a nanostructure is highly dependent on its morphology, but there are few methods for appending a domain as the "functional group" or modifier. As a means of modulating plasmonic properties, we create and modulate Au hats on Au nanoparticles, including mortarboards, beret hats, helmets, crowns, antler hats and antenna hats. The structural control arises from the active surface growth as a result of dynamic competition between ligand absorption and metal deposition. It al ...[more]

PMID: 34163638

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