MOCVD Growth of GeTe/Sb2Te3 Core-Shell Nanowires

We report the self-assembly of core-shell GeTe/Sb Te nanowires (NWs) on Si (100), and SiO /Si substrates by metalorganic chemical vapour deposition, coupled to the vapour-liquid- solid mechanism, catalyzed by Au nanoparticles. Scanning electron microscopy, X-ray diffraction, micro-Raman mapping, high-resolution transmission electron microscopy, and electron energy loss spectroscopy were employed to investigate the morphology, structure, and composition of the obtained core and core-shell NWs. A single crystalline GeTe core and a polycrystalline Sb Te shell formed the NWs, having core and core-shell diameters in the range of 50-130 nm and an average length up to 7 µm.