TEMPERATURE EFFECT ON STRUCTURAL AND ELECTRONIC PROPERTIES OF ZINC OXIDE NANOWIRES SYNTHESIZED BY CARBOTHERMAL EVAPORATION METHOD.

ORVATINIA, MOHAMMAD; IMANI, ROGHAYEH

Zinc Oxide () nanowires were synthesized on the substrates by carbothermal evaporation of at elevated temperatures. The syntheses were carried out at different temperatures from 750°C to 950°C. Characterizations of layers were performed to study the effect of synthesis temperature on morphology, crystal structure and electrical behavior of fabricated nanowires. The physical characterization was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDAX) methods. SEM micrograph of layers revealed that the samples grown at the lower temperatures have better quality. However, below 800°C the growth of nanowires was stopped. So the 800°C was concluded to be the optimum temperature for growth of high quality nanowires by proposed system. By recording the conductivity variations as a function of inverse temperature, 1/T, the semiconductor property of the samples was verified. It is demonstrated that two distinct factors affect the electrical conductivity of layers, which are due to the bulk and grain boundary. We experimentally proved that the activation energy corresponding to grain boundary is higher than that of the bulk. As another result we have established for the first time that by increasing synthesis temperatures, both activation energies shift to higher values.

TEMPERATURE effect; ELECTRONIC structure; ZINC oxide; SYNTHESIS of nanowires; EVAPORATION (Chemistry); SCANNING electron microscopy; CRYSTAL grain boundaries

International Journal of Nanoscience, 2012, Vol 11, Issue 5, p-1

0219-581X

Academic Journal

10.1142/S0219581X12500329