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Photoacoustics for listening to metal nanoparticle super-aggregates.

ABSTRACT: Photoacoustic signal detection has been used to build a new strategy to determine the mesoscale self-assembly of metal nanoparticles in terms of size distribution and aggregate packing density (metal nanoparticle filling factor). A synergistic approach integrating photoacoustic signal and theoretical studies, validated by conventional light scattering and electron microscopy techniques, allows us to obtain a well-defined morphological interpretation of nanoparticle-based super-aggregates. By pumping light in a complex system, the acousto-thermal effect was listened to, providing information on the aggregation phenomena. Super-aggregates of covalently interconnected silver nanoparticles (AgNPs) functionalized with an organometallic dithiol are identified in solution, as a proof of concept for the versatility of the photoacoustic approach. According to our results, tiny AgNPs (size less than 10 nm) assembled into a 3D-network of super-aggregates (SA-AgNPs) with sizes in the range 100-200 nm and a filling factor in the range of 30-50%. Low-cost, rapid, and easy photoacoustic measurement in the low frequency range (less than 100 Hz) was revealed to be an innovative method to characterize the fundamental structure/property correlation of metal nanoparticle super-aggregates. This morpho-optical approach, which uses the absorption and scattering properties of nanoparticles in the liquid phase, opens new perspectives for advanced biomedical and structural applications.

SUBMITTER: Li Voti R

PROVIDER: S-EPMC9417617 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Photoacoustics for listening to metal nanoparticle super-aggregates.

Li Voti Roberto R Leahu Grigore G Sibilia Concita C Matassa Roberto R Familiari Giuseppe G Cerra Sara S Salamone Tommaso Alberto TA Fratoddi Ilaria I

Nanoscale advances 20210618 16

Photoacoustic signal detection has been used to build a new strategy to determine the mesoscale self-assembly of metal nanoparticles in terms of size distribution and aggregate packing density (metal nanoparticle filling factor). A synergistic approach integrating photoacoustic signal and theoretical studies, validated by conventional light scattering and electron microscopy techniques, allows us to obtain a well-defined morphological interpretation of nanoparticle-based super-aggregates. By pum ...[more]

PMID: 36134303

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Dataset Information

Photoacoustics for listening to metal nanoparticle super-aggregates.

Publications

Photoacoustics for listening to metal nanoparticle super-aggregates.

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