Atomic Structure of Wurtzite CdSe (Core)/CdS (Giant Shell) Nanobullets Related to Epitaxy and Growth

作者：Bladt Eva; van Dijk Moes Relinde J A; Peters Joep; Montanarella Federico; Donega Celso de Mello; Vanmaekelbergh Daniel; Bals Sara^*

来源：Journal of the American Chemical Society, 2016, 138(43): 14288-14293.

DOI：10.1021/jacs.6b06443

Heteronanocrystals consisting of a CdSe core and a giant CdS shell have shown remarkable optical properties which are promising for applications in optoelectrical devices. Since these properties sensitively depend on the size and shape, a morphological characterization is of high interest. Here, we present a high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) study of CdSe (core)/CdS (giant shell) heteronanocrystals. Electron tomography reveals that the nanocrystals have a bullet shape, either ending in a tip or a small dip, and that the CdSe core is positioned closer to the tip (Or dip) than to the hexagonal base. Based on a high resolution HAADF-STEM study, we were able to determine all the surface facets. We present a heuristic model for the different growth stages of the CdS crystal around the CdSe core.

• 出版日期2016-11-2