Fabrication and characterization of varistor-polymer composite based on zinc oxide

This research focuses on fabricating a varistor-polymer composite based on nanosized ZnO and micro-sized ZnO, and comparing their current-voltage characteristics. In addition, the influence of each dopant (Bi2O3, MnO, Co3O4) on the physical and electrical properties of varistor-polymer composite bas...

Full description

Saved in:
Bibliographic Details
Main Author: Fatehi, Asma
Format: Thesis
Language:English
Published: 2012
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/31404/1/FS%202012%2072R.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.31404
record_format uketd_dc
spelling my-upm-ir.314042015-02-10T01:53:07Z Fabrication and characterization of varistor-polymer composite based on zinc oxide 2012-12 Fatehi, Asma This research focuses on fabricating a varistor-polymer composite based on nanosized ZnO and micro-sized ZnO, and comparing their current-voltage characteristics. In addition, the influence of each dopant (Bi2O3, MnO, Co3O4) on the physical and electrical properties of varistor-polymer composite based on zinc oxide is investigated. Nano-sized varistor powder, micro-sized varistor powder and Bi2O3-MnO-Co3O4 doped ZnO micro powder were prepared via a combined solution and standard ceramic processing. Fabrication of a varistor-polymer nanocomposite and microcomposite was accomplished by the melt-blending technique. The characterization of varistor-polymer composites was carried out by X-ray diffraction data (XRD) analysis, Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Energy dispersive X-ray (EDAX), Thermal Gravimetry Analysis (TGA) and Fourier Transform Infra-red (FTIR) spectroscopy. The XRD pattern of nanocomposite revealed the high crystallinity of the composite compared to microcomposite. FTIR spectra confirmed physical interacting of polymer and varistor powder. TGA and DSC results revealed that temperature degradation and melting temperatures of nano composite were increased compared to micro composite. Manganese Oxide as one dopant of varistor powder stabilize thermal resistivity of the varistor-polymer composite compared to other metal oxides. The TEM image showed the spherical morphology of the nano-sized filler with the average size below 50 nm which were distributed homogeneously within the polymer. While, the SEM micrograph revealed the non uniform distribution of micro-sized fillers. FESEM and EDAX showed the presence of a bismuth-rich phase and a ZnO phase in the varistor powder. The current-voltage (I-V) characteristics suggested varistor-like behaviour when the concentration of nano-sized filler increased in contrast to micro-sized filler. Bismuth Oxide (as one dopant of varistor powder) has an important role in nonlinear properties of varistor-polymer composites. Varistors Polymeric composites Zinc oxide 2012-12 Thesis http://psasir.upm.edu.my/id/eprint/31404/ http://psasir.upm.edu.my/id/eprint/31404/1/FS%202012%2072R.pdf application/pdf en public masters Universiti Putra Malaysia Varistors Polymeric composites Zinc oxide Faculty of Science
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
topic Varistors
Polymeric composites
Zinc oxide
spellingShingle Varistors
Polymeric composites
Zinc oxide
Fatehi, Asma
Fabrication and characterization of varistor-polymer composite based on zinc oxide
description This research focuses on fabricating a varistor-polymer composite based on nanosized ZnO and micro-sized ZnO, and comparing their current-voltage characteristics. In addition, the influence of each dopant (Bi2O3, MnO, Co3O4) on the physical and electrical properties of varistor-polymer composite based on zinc oxide is investigated. Nano-sized varistor powder, micro-sized varistor powder and Bi2O3-MnO-Co3O4 doped ZnO micro powder were prepared via a combined solution and standard ceramic processing. Fabrication of a varistor-polymer nanocomposite and microcomposite was accomplished by the melt-blending technique. The characterization of varistor-polymer composites was carried out by X-ray diffraction data (XRD) analysis, Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Energy dispersive X-ray (EDAX), Thermal Gravimetry Analysis (TGA) and Fourier Transform Infra-red (FTIR) spectroscopy. The XRD pattern of nanocomposite revealed the high crystallinity of the composite compared to microcomposite. FTIR spectra confirmed physical interacting of polymer and varistor powder. TGA and DSC results revealed that temperature degradation and melting temperatures of nano composite were increased compared to micro composite. Manganese Oxide as one dopant of varistor powder stabilize thermal resistivity of the varistor-polymer composite compared to other metal oxides. The TEM image showed the spherical morphology of the nano-sized filler with the average size below 50 nm which were distributed homogeneously within the polymer. While, the SEM micrograph revealed the non uniform distribution of micro-sized fillers. FESEM and EDAX showed the presence of a bismuth-rich phase and a ZnO phase in the varistor powder. The current-voltage (I-V) characteristics suggested varistor-like behaviour when the concentration of nano-sized filler increased in contrast to micro-sized filler. Bismuth Oxide (as one dopant of varistor powder) has an important role in nonlinear properties of varistor-polymer composites.
format Thesis
qualification_level Master's degree
author Fatehi, Asma
author_facet Fatehi, Asma
author_sort Fatehi, Asma
title Fabrication and characterization of varistor-polymer composite based on zinc oxide
title_short Fabrication and characterization of varistor-polymer composite based on zinc oxide
title_full Fabrication and characterization of varistor-polymer composite based on zinc oxide
title_fullStr Fabrication and characterization of varistor-polymer composite based on zinc oxide
title_full_unstemmed Fabrication and characterization of varistor-polymer composite based on zinc oxide
title_sort fabrication and characterization of varistor-polymer composite based on zinc oxide
granting_institution Universiti Putra Malaysia
granting_department Faculty of Science
publishDate 2012
url http://psasir.upm.edu.my/id/eprint/31404/1/FS%202012%2072R.pdf
_version_ 1747811610056982528