Doped ZnO nanowires: Towards homojuctions

Zinc oxide nanowire networks have been prepared using evaporation/condensation technique with a modified set-up that allows the control of the doping present in the gas phase during the growth. The doping process has been studied for the development of homo-junctions. ZnO nanowires with uniform copper addition first and then non-uniform doping distribution have been prepared. Morphology, crystalline structure, and elemental composition of nanowires structures have been investigated using scanning and transmission electron microscopy, and related energy dispersive spectroscopy. Chemical composition of the nanowires was investigated by using X-ray Photoelectron Spectroscopy (XPS), which is a surface-sensitive technique supplying qualitative (chemical bonding) and quantitative (atomic concentration) information. Atomic concentration of Cu dopant in the nanowires networks was determined from the data of XPS measurements.