Microstructural changes in CdSe-coated ZnO nanowires evaluated by in situ annealing in transmission electron microscopy and x-ray diffraction.
Nanotechnology
; 23(26): 265701, 2012 Jul 05.
Article
em En
| MEDLINE
| ID: mdl-22699426
ABSTRACT
We report on the crystallite growth and phase change of electrodeposited CdSe coatings on ZnO nanowires during annealing. Both in situ transmission electron microscopy (TEM) and x-ray diffraction (XRD) reveal that the nanocrystal size increases from â¼3 to â¼10 nm upon annealing at 350 °C for 1 h and then to more than 30 nm during another 1 h at 400 °C, exhibiting two distinct growth regimes. Nanocrystal growth occurs together with a structural change from zinc blende to wurtzite. The structural transition begins at 350 °C, which results in the formation of stacking faults. Increased crystallite size, comparable to the coating thickness, can improve charge separation in extremely thin absorber solar cells. We demonstrate a nearly two-fold improvement in power conversion efficiency upon annealing.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Nanotechnology
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos