Preparation of aluminum-doped zinc oxide (AZO) nano particles by hydrothermal synthesis

Faculty of Science and Art, Department of Chemistry, Akdeniz University, 07058 Antalya, Turkey
Journal of Sol-Gel Science and Technology (Impact Factor: 1.55). 08/2010; 55(2):171-176. DOI: 10.1007/s10971-010-2229-2

ABSTRACT Aluminum doped zinc oxide (AZO) nanometric particles were synthesized by hydrothermal method. Aluminum nitrate hydrate, aluminum
sec-butoxide and zinc nitrate hydrate were used as the starting materials, and n-propanol and 2-butanol were used as solvents.
Ratio of Al2O3 in ZnO was kept at 10 wt%. Reaction was conducted in a Teflon autoclave at 175–225°C for 5h. Ratios of alcohol, H2O and HCl to zinc nitrate hydrate were altered and 6 different sets of parameters were investigated. Obtained products were
subjected to powder-XRD, particle size measurement, TEM examination and AAS analysis. Single phase AZO particles were obtained
at alcohol to zinc nitrate ratio of 35, acid to zinc nitrate ratio of 0.2, at 225°C. Particle size was determined as 3.2±0.4nm
from TEM examinations and as 1–2nm from dynamic light scattering. Synthesized particles have amphiphilic character, thus
they can be dispersed in both polar and non-polar media. It was seen from the UV-diffuse reflectance spectra that the AZO
powder had low reflectance in the UV region and high reflectance in the visible region. The obtained powder has the potential
to be utilized in the form of thin films for optical and electronic purposes.

KeywordsSol–gel processes-Hydrothermal synthesis-Aluminum doped zinc oxide (AZO)-Nanoparticle

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