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Galvanic Exchange in Colloidal Metal/Metal-Oxide Core/Shell Nanocrystals.

ABSTRACT: While galvanic exchange is commonly applied to metallic nanoparticles, recently its applicability was expanded to metal-oxides. Here the galvanic exchange is studied in metal/metal-oxide core/shell nanocrystals. In particular Sn/SnO2 is treated by Ag(+), Pt(2+), Pt(4+), and Pd(2+). The conversion dynamics is monitored by in situ synchrotron X-ray diffraction. The Ag(+) treatment converts the Sn cores to the intermetallic Ag x Sn (x ? 4) phase, by changing the core's crystal structure. For the analogous treatment by Pt(2+), Pt(4+), and Pd(2+), such a galvanic exchange is not observed. This different behavior is caused by the semipermeability of the naturally formed SnO2 shell, which allows diffusion of Ag(+) but protects the nanocrystal cores from oxidation by Pt and Pd ions.

SUBMITTER: Kriegner D

PROVIDER: S-EPMC5018861 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Galvanic Exchange in Colloidal Metal/Metal-Oxide Core/Shell Nanocrystals.

Kriegner Dominik D Sytnyk Mykhailo M Groiss Heiko H Yarema Maksym M Grafeneder Wolfgang W Walter Peter P Dippel Ann-Christin AC Meffert Matthias M Gerthsen Dagmar D Stangl Julian J Heiss Wolfgang W

The journal of physical chemistry. C, Nanomaterials and interfaces 20160815 35

While galvanic exchange is commonly applied to metallic nanoparticles, recently its applicability was expanded to metal-oxides. Here the galvanic exchange is studied in metal/metal-oxide core/shell nanocrystals. In particular Sn/SnO2 is treated by Ag+, Pt2+, Pt4+, and Pd2+. The conversion dynamics is monitored by in situ synchrotron X-ray diffraction. The Ag+ treatment converts the Sn cores to the intermetallic Ag x</s ...[more]

PMID: 27635186

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