Effect of cobalt doping on the mechanical and structural properties of ZnO nanowires

5^th World Congress on Materials Science & Engineering

June 13-15, 2016 Alicante, Spain

Mikk Vahtrus

University of Tartu, Estonia

Posters & Accepted Abstracts: J Material Sci Eng

Abstract :

Zinc oxide (ZnO) nanostructures have attracted a lot of attention due to the combination of favorable physical properties of ZnO such as being semiconductive, piezoelectric, and biocompatible. At the same time, ZnO is not efficient in the visual part of the spectrum due to its wide band gap (~3.3 eV), which limits the commercial application of these materials as photocatalyst. Transition metal doping has been used to improve the photocatalytic properties of ZnO nanostructures with Co being one of the most efficient dopants. Meanwhile, doping could lead to the deterioration of mechanical properties, which are important for designing devices with predictable and reproducible properties. In the current work we compared the mechanical and structural properties of pure and 5% Co-doped ZnO NWs synthesized by solvothermal method. XRD measurement revealed zincite structure for both samples. HR-SEM and TEM images showed uniform morphology with hexagonal cross section and smooth surfaces for synthesized NWs. Atomic force microscopy (AFM) based 3-point bending and cantilever beam bending inside high resolution scanning electron microscopy (HR-SEM) were used to obtain Young�s modulus and bending strength values. We found that mechanical properties for both types of NWs are size dependent and increase with the decrease of diameter. Furthermore, Co-doped ZnO exhibit lower Young�s modulus and bending strength values compared to pure ZnO NWs. Lower values can be explained by the introduction of vacancies and defects due to doping with Co.

Biography :

Email: mikk.vahtrus@gmail.com