Growth and microstructure for visible emission and surface optical phonon mode of Zn–ZnO nanostructure

Abstract

The Zn–ZnO nanostructured thin films were prepared in carbon matrix using a cost-effective vacuum-carbon arc method. On increasing graphitization with ZnO, the grazing incidence X-ray diffraction pattern showed that the intensity of the ZnO peak increases, whereas that of the Zn peak decreases. X-ray line profile analysis and transmission electron microscopy were employed to investigate the microstructural evolution of Zn–ZnO nanostructure during vacuum arc processing. A growth mechanism is proposed for the Zn–ZnO nanostructure when reaction with carbon-containing gas inside the reactor wall takes place. Detailed studies of photoluminescence bands clearly exhibit the intensity variation of violet and blue-green bands on increasing graphitization ratio. Using the dielectric continuum approach, surface optical phonon modes of the Zn–ZnO nanostructure were studied for different synthesized samples.

Keywords:

• nanostructures
• defect emission
• surface optical phonon
• Rietveld refinement

Acknowledgements

The authors are thankful to Dr. B. Mishra, Department of Geology & Geophysics, IIT Kharagpur for providing Raman scattering facility in his laboratory. One of the authors, A. Ghosh, acknowledges IIT Kharagpur and CSIR, New Delhi, India for financial support to carry out this work.