Summary: | In this work, zinc oxide powder is synthesized via the hydrothermal method.
In the experimental procedure producing the ZnO powder, acetate buffer solution,
sodium hydroxide, zinc nitrate hexahydrate solution (0.1 M and 1.0 M) and urea
solution (0.2 M and 2.0M) are mixed under stirred condition in a pressure reactor.
The molar concentration ratio of zinc nitrate hexahydrate to urea is 1 :2. The reaction
time studied was at 3 hours and 5 hours at temperatures of 130°C and 150°C. The
precipitates were dried after filtration and then calcination at 400°C. SEM analysis
showed different types of morphology observed in the powders produced at varying
reaction time and temperature. They were nano flakes-like shape, rod shape and
hexagonal rod shape. The average thickness of the nano flakes structure obtained
range from 7.49nm to 63.21nm. As for the rod shape particles, the width and length
of the rod is 1. 724Jlm and 10.63 Jlm respectively. Overall EDX results, did not show
the presence of other elemental peaks. From XRD analysis, the crystallite size of the
samples produced range from 197.4A to 662.9A. The percentage of zinc oxide
present in the sample from the XRF analysis is around 98.8 %. Results from thermal
analysis (TGA/DT A) showed that the zinc oxide powder produced are stable with no
significant change in mass. Zinc oxide powder with homogeneous distribution of
nano flakes-like structure can be synthesized via hydrothermal process w1der low
concentration of chemical precursors and at low reaction temperature and shorter
reaction time.
|