Synthesis and characterization of core-shell ZnO/ZnSe nanowires grown by MOCVD

Autor: Gaëlle Amiri, Christèle Vilar, Vincent Sallet, Ahmed Souissi, Nadia Haneche, Alain Lusson, Pierre Galtier
Rok vydání: 2013
Předmět:
Zdroj: physica status solidi (b). 250:2132-2136
ISSN: 0370-1972
Popis: ZnO/ZnSe core/shell nanowire arrays have been grown by metal-organic chemical vapor deposition on c-plane sapphire. The morphology and the structure of the nanostructures were characterized by scanning electron microscopy and transmission electron microscopy. They exhibit well-aligned core/shell ZnO/ZnSe nanowires with a good crystalline quality although some surface roughness is associated to the deposition of ZnSe on the lateral ZnO facets. X-ray diffraction combined with Raman spectroscopy and electron diffraction demonstrate that ZnO grows along the c-axis with the wurtzite (W) structure, but ZnSe can be deposited epitaxially in the zinc-blende (ZB) structure on the M-facet of the wires. Optical transmission measurements reveal an additional contribution at about 2.15 eV attributed to the type-II interfacial transition between the valence band of ZB-ZnSe and the conduction band of W-ZnO. These observations confirm the potential interest of ZnO/ZnSe core/shell nanostructures for photovoltaic applications.
Databáze: OpenAIRE