SpringerOpen Newsletter

Receive periodic news and updates relating to SpringerOpen.

Open Access Nano Express

The nitridation of ZnO nanowires

Matthew Zervos1*, Chrystalla Karipi1 and Andreas Othonos2

Author Affiliations

1 Nanostructured Materials and Devices Laboratory, Department of Mechanical Engineering, Materials Science Group, University of Cyprus, P.O. Box 20537, Nicosia, 1678, Cyprus

2 Research Center of Ultrafast Science, Department of Physics, School of Physical Sciences, University of Cyprus, P.O. Box 20537, Nicosia, 1678, Cyprus

For all author emails, please log on.

Nanoscale Research Letters 2012, 7:175  doi:10.1186/1556-276X-7-175

Published: 8 March 2012

Abstract

ZnO nanowires (NWs) with diameters of 50 to 250 nm and lengths of several micrometres have been grown by reactive vapour transport via the reaction of Zn with oxygen on 1 nm Au/Si(001) at 550°C under an inert flow of Ar. These exhibited clear peaks in the X-ray diffraction corresponding to the hexagonal wurtzite crystal structure of ZnO and a photoluminescence spectrum with a peak at 3.3 eV corresponding to band edge emission close to 3.2 eV determined from the abrupt onset in the absorption-transmission through ZnO NWs grown on 0.5 nm Au/quartz. We find that the post growth nitridation of ZnO NWs under a steady flow of NH3 at temperatures ≤600°C promotes the formation of a ZnO/Zn3N2 core-shell structure as suggested by the suppression of the peaks related to ZnO and the emergence of new ones corresponding to the cubic crystal structure of Zn3N2 while maintaining their integrity. Higher temperatures lead to the complete elimination of the ZnO NWs. We discuss the effect of nitridation time, flow of NH3, ramp rate and hydrogen on the conversion and propose a mechanism for the nitridation.

Keywords:
zinc oxide; zinc nitride; nanowires; nitridation