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

Yalcin, Anil O; Fan, Zhaochuan; Goris, Bart; Li, Wun-Fan; Koster, Rik S; Fang, Chang-Ming; van Blaaderen, Alfons; Casavola, Marianna et al. · Nano Lett · 2014

basic_science · Level V

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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.