Luminescence properties of SiC/SiO2 core-shell nanowires with different radial structure

The luminescence properties of SiC/SiO2 core/shell nanowires with different core to shell thickness ratio are analysed by SEM-Cathodoluminescence spectroscopy. The different radial NW structure, studied by transmission electron microscopy, deeply influences the efficiency of competitive radiative transitions. As the core to shell ratio decreases, the increase of a UV emission component is observed indicating that the electron-hole pairs recombine directly in the silicon dioxide and the beneficial effect of shell-induced enhancement of the core emissions is less efficient.