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Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique. / Afshin Tarat

Swansea University Author: Afshin Tarat

Abstract

Zinc oxide (ZnO) crystal with a direct wide band gap (3.37 eV) and large excition binding energy (60 meV) is one of the most potential semiconductors in numerous application fields such as room-temperature UV-Iaser, light-emitting- diode (LED), photocatalyst, gas sensor, solar cell, piezoelectric de...

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Published: 2014
Institution: Swansea University
Degree level: Doctoral
Degree name: Ph.D
URI: https://cronfa.swan.ac.uk/Record/cronfa42303
first_indexed 2018-08-02T18:54:23Z
last_indexed 2018-08-03T10:09:47Z
id cronfa42303
recordtype RisThesis
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spelling 2018-08-02T16:24:28.7449973 v2 42303 2018-08-02 Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique. ba04e2393c4207212933e493bcba3697 NULL Afshin Tarat Afshin Tarat true true 2018-08-02 Zinc oxide (ZnO) crystal with a direct wide band gap (3.37 eV) and large excition binding energy (60 meV) is one of the most potential semiconductors in numerous application fields such as room-temperature UV-Iaser, light-emitting- diode (LED), photocatalyst, gas sensor, solar cell, piezoelectric device, etc. In past decades, different methods have been investigated to produce a variety of different shapes of nano and submicron ZnO nanostructures. Among them, the ZnO nanobelts (NBs) with a rectangular cross section have unique optoelectronic properties due to its unusual shape and structure. It is well demonstrated by recent success in field-effect transistor, nanoresonator, and spintronics applications of the ZnO NBs. Two-dimensional (2D) nanostructures such as nanosheets (NSs) and thin films have also great potential for unique purposes where a large uniform coverage at nanoscale is essential. One of the conventional methods for synthesis of the ZnO nanostructures is vapour transport and condensation process at high temperature, in some cases up to 1400&deg;C. Such an extreme condition for vaporization of precursor could induce many oxygen defects on surface of the ZnO nanobelts. These specific defects hinder progress to the applications of ZnO in optoelectronic and lasing devices. In this respect, mild processing is strongly demanded for the synthesis of the ZnO nanoparticles. In terms of low energy consumption and simplicity, soft- solution process based on hydrothermal reactions at low temperature (under 100&deg;C) is a green chemical procedure. However, there are only few reports on the synthesis of the ZnO NBs and NSs due to their unusual growth habit against typical growth rate of the ZnO crystal. Here we are reporting a developed simple, low cost and high yield hydrothermal technique to synthesis layered basic zinc acetate (LBZA) NBs and also a novel rapid microwave-assisted hydrothermal technique to grow LBZA NSs only in 2 minutes. Growth procedures are followed by pyrolytic decomposition to produce nanocrystalline NBs and NSs. SEM and AFM results revealed that the morphology and quantity of the nanobelts and nanosheets are strongly temperature and pH dependent. In addition, results showed that as-grown LBZA nanostructures could be easily transformed to corresponding ZnO nanostructures through pyrolytic decomposition without. E-Thesis Materials science.;Nanotechnology. 31 12 2014 2014-12-31 COLLEGE NANME Engineering COLLEGE CODE Swansea University Doctoral Ph.D 2018-08-02T16:24:28.7449973 2018-08-02T16:24:28.7449973 Faculty of Science and Engineering School of Engineering and Applied Sciences - Uncategorised Afshin Tarat NULL 1 0042303-02082018162443.pdf 10798011.pdf 2018-08-02T16:24:43.8770000 Output 27261003 application/pdf E-Thesis true 2018-08-02T16:24:43.8770000 false
title Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
spellingShingle Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
Afshin Tarat
title_short Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
title_full Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
title_fullStr Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
title_full_unstemmed Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
title_sort Nanocrystalline ZnO obtained from pyrolytic decomposition of layered basic zinc acetate: Introducing a novel rapid microwave-assisted hydrothermal technique.
author_id_str_mv ba04e2393c4207212933e493bcba3697
author_id_fullname_str_mv ba04e2393c4207212933e493bcba3697_***_Afshin Tarat
author Afshin Tarat
author2 Afshin Tarat
format E-Thesis
publishDate 2014
institution Swansea University
college_str Faculty of Science and Engineering
hierarchytype
hierarchy_top_id facultyofscienceandengineering
hierarchy_top_title Faculty of Science and Engineering
hierarchy_parent_id facultyofscienceandengineering
hierarchy_parent_title Faculty of Science and Engineering
department_str School of Engineering and Applied Sciences - Uncategorised{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Engineering and Applied Sciences - Uncategorised
document_store_str 1
active_str 0
description Zinc oxide (ZnO) crystal with a direct wide band gap (3.37 eV) and large excition binding energy (60 meV) is one of the most potential semiconductors in numerous application fields such as room-temperature UV-Iaser, light-emitting- diode (LED), photocatalyst, gas sensor, solar cell, piezoelectric device, etc. In past decades, different methods have been investigated to produce a variety of different shapes of nano and submicron ZnO nanostructures. Among them, the ZnO nanobelts (NBs) with a rectangular cross section have unique optoelectronic properties due to its unusual shape and structure. It is well demonstrated by recent success in field-effect transistor, nanoresonator, and spintronics applications of the ZnO NBs. Two-dimensional (2D) nanostructures such as nanosheets (NSs) and thin films have also great potential for unique purposes where a large uniform coverage at nanoscale is essential. One of the conventional methods for synthesis of the ZnO nanostructures is vapour transport and condensation process at high temperature, in some cases up to 1400&deg;C. Such an extreme condition for vaporization of precursor could induce many oxygen defects on surface of the ZnO nanobelts. These specific defects hinder progress to the applications of ZnO in optoelectronic and lasing devices. In this respect, mild processing is strongly demanded for the synthesis of the ZnO nanoparticles. In terms of low energy consumption and simplicity, soft- solution process based on hydrothermal reactions at low temperature (under 100&deg;C) is a green chemical procedure. However, there are only few reports on the synthesis of the ZnO NBs and NSs due to their unusual growth habit against typical growth rate of the ZnO crystal. Here we are reporting a developed simple, low cost and high yield hydrothermal technique to synthesis layered basic zinc acetate (LBZA) NBs and also a novel rapid microwave-assisted hydrothermal technique to grow LBZA NSs only in 2 minutes. Growth procedures are followed by pyrolytic decomposition to produce nanocrystalline NBs and NSs. SEM and AFM results revealed that the morphology and quantity of the nanobelts and nanosheets are strongly temperature and pH dependent. In addition, results showed that as-grown LBZA nanostructures could be easily transformed to corresponding ZnO nanostructures through pyrolytic decomposition without.
published_date 2014-12-31T07:25:30Z
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score 11.047306

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