Effects of Synthesis Methods on the Physicochemical Properties of Micro- and Nano-Sized Zinc Oxide

Keshavarzi, Ashkan (2009) Effects of Synthesis Methods on the Physicochemical Properties of Micro- and Nano-Sized Zinc Oxide. Masters thesis, Universiti Putra Malaysia.

[img] PDF
454Kb

Abstract

Zinc oxide is an important semiconductor material, which is useful in various applications such as photo-electric devices electronic devices, surface acoustic wave, devices field emitters sensors, ultraviolet lasers and solar cells. With a wurtzite hexagonal phase, ZnO have a direct band gap of 3.37 eV with the larger exciton binding energy (60 meV), possesses a wide range of technological applications including flat panel displays, UV lasers and chemical and biological sensors. Till now, many methods have been developed to synthesize zinc oxide nanocrystals including vapor phase growth, ultrasonic irradiation, hydrothermal, pulsed lased deposition, vapor–liquid–solid process, soft chemical method, electrophoretic deposition, sol–gel process. Depending on the adopted synthesis method, zinc oxide nanocrystals would show various morphologies under different formation mechanisms.In this work, we studied preparation of ultra fine and nano sized ZnO by four important methods. ZnO nanoparticle, nanorod, nanowire have been successfully synthesized by facile methods like ultrasonic irradiation, sol-gel method, decomposition of Zn substrate and hydrothermal methods. In our work, three anionic surfactants Cetyl trimethylammonium bromide (CTAB), Tetrabutylammonium bromide (TBAB) and Sodium dodecyl sulfate (SDS) have been used as capping agent in the hydrothermal process. The results demonstrated that structure of the surfactant and its carbonyl chain group is important to crystal growth of the products. SEM and TEM micrograph revealed that nano fiber and ultrafine spherical ZnO prepared in the presence of CTAB and TBAB, but in the presence of SDS, sheet form of ZnO was prepared. The effect of ultrasonic irradiation was studied on preparation of ZnO. Nanoparticle of ZnO was synthesized after precipitation of zinc nitrate by urea at 90°C with irradiation of waves into the reaction flask for 2h. After heat treat at 350°C, sample was characterized with FT-IR, XRD, SEM, TEM and UV-vis. The results shows the nanoparticles of ZnO are in size range of 50-120nm. The effect of solvent was studied in this work, too. Ethanol, ethylene glycol and isopropanol were used as solvent in the reaction. In the other hand, characterization of products was shown that morphology and particle size of products was very different and depended to the dielectric constant of the solvents.

Item Type:Thesis (Masters)
Subject:Zinc oxide - Case studies
Chairman Supervisor:Associate Professor Abdul Halim Bin Abdulah, PhD
Call Number:FS 2009 32
Faculty or Institute:Faculty of Science
ID Code:7550
Deposited By: Nurul Hayatie Hashim
Deposited On:22 Jul 2010 03:57
Last Modified:27 May 2013 07:35

Repository Staff Only: Edit item detail

Document Download Statistics

This item has been downloaded for since 22 Jul 2010 03:57.

View statistics for "Effects of Synthesis Methods on the Physicochemical Properties of Micro- and Nano-Sized Zinc Oxide "


Universiti Putra Malaysia Institutional Repository

Universiti Putra Malaysia Institutional Repository is an on-line digital archive that serves as a central collection and storage of scientific information and research at the Universiti Putra Malaysia.

Currently, the collections deposited in the IR consists of Master and PhD theses, Master and PhD Project Report, Journal Articles, Journal Bulletins, Conference Papers, UPM News, Newspaper Cuttings, Patents and Inaugural Lectures.

As the policy of the university does not permit users to view thesis in full text, access is only given to the first 24 pages only.