Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan
This work reports on the investigation of NiSi/SiC core – shell nanowires grown by hot – wire chemical vapor deposition technique on crystalline Si (c-Si) and Ni foil substrates. This work was divided into two parts. In the first part, the effect of different substrate temperatures (350⁰C to 530⁰...
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| Format: | Thesis |
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2017
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| Online Access: | http://studentsrepo.um.edu.my/9183/ http://studentsrepo.um.edu.my/9183/2/Najwa_Hamzan.pdf http://studentsrepo.um.edu.my/9183/6/najwa.pdf |
| _version_ | 1848773857649885184 |
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| author | Najwa , Hamzan |
| author_facet | Najwa , Hamzan |
| author_sort | Najwa , Hamzan |
| building | UM Research Repository |
| collection | Online Access |
| description | This work reports on the investigation of NiSi/SiC core – shell nanowires grown
by hot – wire chemical vapor deposition technique on crystalline Si (c-Si) and Ni foil
substrates. This work was divided into two parts. In the first part, the effect of different
substrate temperatures (350⁰C to 530⁰C) on growth and structural properties of the
nanowires were studied with SiH4 to CH4 gas flow rates fixed at 1:2. These core-shell
nanowires were found to be grown at substrate temperatures above 350⁰C. The
nanowires consisted of single crystalline NiSi core and polycrystalline SiC nanocolumn
shell. Increase of the substrate temperature enhances the growth of high density
vertically aligned nanowires with increment of 2%. The electrochemical properties of
NiSi/SiC core-shell nanowires also have been investigated. The specific capacitance of
the NiSi/SiC core-shell nanowires obtained from the cyclic voltammetry curve was
about 75 mF/cm2, which was nearly three times higher than the intrinsic NiSi nanowires
(21 mF/cm2) and four times higher than the blank Ni foil (17 mF/cm2). In the second
part, the effects of different CH4 flow rate (0.5 sccm to 3.5 sccm) on the growth,
structural and electrochemical properties of the nanowires were investigated. The
nanowires were found to be grown at CH4 flow rate above 0.5 sccm. The
microstructures studies of these nanowires have demonstrated a single crystalline NiSi
core and polycrystalline SiC nanocolumn shell, respectively. In addition, CH4 flow rates
also affect the diameter of core and thickness of shell of nanowires. The diameter of core
and thickness of shell of nanowires noticeably increased with the increased in CH4 flow
rates from 0.5 sccm to 3.5 sccm. The diameter of core of nanowire increased from 19.48
nm to 20.00 nm while thickness of shell of nanowire increased from 54.58 nm to 120.00
nm. The NiSi/SiC core-shell nanowire electrode at 2.0 sccm exhibited an excellent
electrochemical performance as compared to other flow rates. The core - shell nanowire
electrode has achieved a maximum specific capacitance of 234.13 mF/cm2. |
| first_indexed | 2025-11-14T13:49:04Z |
| format | Thesis |
| id | um-9183 |
| institution | University Malaya |
| institution_category | Local University |
| last_indexed | 2025-11-14T13:49:04Z |
| publishDate | 2017 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | um-91832020-06-23T00:05:08Z Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan Najwa , Hamzan Q Science (General) QC Physics This work reports on the investigation of NiSi/SiC core – shell nanowires grown by hot – wire chemical vapor deposition technique on crystalline Si (c-Si) and Ni foil substrates. This work was divided into two parts. In the first part, the effect of different substrate temperatures (350⁰C to 530⁰C) on growth and structural properties of the nanowires were studied with SiH4 to CH4 gas flow rates fixed at 1:2. These core-shell nanowires were found to be grown at substrate temperatures above 350⁰C. The nanowires consisted of single crystalline NiSi core and polycrystalline SiC nanocolumn shell. Increase of the substrate temperature enhances the growth of high density vertically aligned nanowires with increment of 2%. The electrochemical properties of NiSi/SiC core-shell nanowires also have been investigated. The specific capacitance of the NiSi/SiC core-shell nanowires obtained from the cyclic voltammetry curve was about 75 mF/cm2, which was nearly three times higher than the intrinsic NiSi nanowires (21 mF/cm2) and four times higher than the blank Ni foil (17 mF/cm2). In the second part, the effects of different CH4 flow rate (0.5 sccm to 3.5 sccm) on the growth, structural and electrochemical properties of the nanowires were investigated. The nanowires were found to be grown at CH4 flow rate above 0.5 sccm. The microstructures studies of these nanowires have demonstrated a single crystalline NiSi core and polycrystalline SiC nanocolumn shell, respectively. In addition, CH4 flow rates also affect the diameter of core and thickness of shell of nanowires. The diameter of core and thickness of shell of nanowires noticeably increased with the increased in CH4 flow rates from 0.5 sccm to 3.5 sccm. The diameter of core of nanowire increased from 19.48 nm to 20.00 nm while thickness of shell of nanowire increased from 54.58 nm to 120.00 nm. The NiSi/SiC core-shell nanowire electrode at 2.0 sccm exhibited an excellent electrochemical performance as compared to other flow rates. The core - shell nanowire electrode has achieved a maximum specific capacitance of 234.13 mF/cm2. 2017-07 Thesis NonPeerReviewed application/pdf http://studentsrepo.um.edu.my/9183/2/Najwa_Hamzan.pdf application/pdf http://studentsrepo.um.edu.my/9183/6/najwa.pdf Najwa , Hamzan (2017) Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan. Masters thesis, University of Malaya. http://studentsrepo.um.edu.my/9183/ |
| spellingShingle | Q Science (General) QC Physics Najwa , Hamzan Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title | Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title_full | Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title_fullStr | Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title_full_unstemmed | Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title_short | Study on the growth of NiSi/SiC core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / Najwa Hamzan |
| title_sort | study on the growth of nisi/sic core – shell nanowires by hot – wire chemical vapor deposition and its application in supercapacitor / najwa hamzan |
| topic | Q Science (General) QC Physics |
| url | http://studentsrepo.um.edu.my/9183/ http://studentsrepo.um.edu.my/9183/2/Najwa_Hamzan.pdf http://studentsrepo.um.edu.my/9183/6/najwa.pdf |