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Atomic resolution monitoring of cation exchange in CdSe-PbSe heteronanocrystals during epitaxial solid-solid-vapor growth.

ABSTRACT: Here, we show a novel solid-solid-vapor (SSV) growth mechanism whereby epitaxial growth of heterogeneous semiconductor nanowires takes place by evaporation-induced cation exchange. During heating of PbSe-CdSe nanodumbbells inside a transmission electron microscope (TEM), we observed that PbSe nanocrystals grew epitaxially at the expense of CdSe nanodomains driven by evaporation of Cd. Analysis of atomic-resolution TEM observations and detailed atomistic simulations reveals that the growth process is mediated by vacancies.

SUBMITTER: Yalcin AO

PROVIDER: S-EPMC4055051 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Atomic resolution monitoring of cation exchange in CdSe-PbSe heteronanocrystals during epitaxial solid-solid-vapor growth.

Yalcin Anil O AO Fan Zhaochuan Z Fan Zhaochuan Z Goris Bart B Li Wun-Fan WF Koster Rik S RS Fang Chang-Ming CM van Blaaderen Alfons A Casavola Marianna M Tichelaar Frans D FD Bals Sara S Van Tendeloo Gustaaf G Vlugt Thijs J H TJ Vanmaekelbergh Daniël D Zandbergen Henny W HW van Huis Marijn A MA

Nano letters 20140523 6

Here, we show a novel solid-solid-vapor (SSV) growth mechanism whereby epitaxial growth of heterogeneous semiconductor nanowires takes place by evaporation-induced cation exchange. During heating of PbSe-CdSe nanodumbbells inside a transmission electron microscope (TEM), we observed that PbSe nanocrystals grew epitaxially at the expense of CdSe nanodomains driven by evaporation of Cd. Analysis of atomic-resolution TEM observations and detailed atomistic simulations reveals that the growth proces ...[more]

PMID: 24844280

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