  We present Al2O3-ZnAl2O4-ZnO nanostructure, which could be a prominent
candidate for optoelectronics, mechanical and sensing applications. While ZnO
and ZnAl2O4 composites are mostly synthesized by sol-gel technique, we propose
a solid-vapor growth mechanism. To produce Al2O3-ZnAl2O4-ZnO nanostructure, we
conduct ZnO:C powder heating resulting in ZnO nanowires (NWs) growth on
sapphire substrate and ZnAl2O4 spinel layer at the interface. The nanostructure
was examined with Scanning Electron Microscopy (SEM) method. Focused Ion Beam
(FIB) technique enabled us to prepare a lamella for Transmission Electron
Microscopy (TEM) imaging. TEM examination revealed high crystallographic
quality of both spinel and NW structure. Epitaxial relationships of
Al2O3-ZnAl2O4 and ZnAl2O4-ZnO are given.
