Enhancement of reflectance of densified vertically aligned carbon nanotube forests
Vertically aligned carbon nanotubes (VACNTs), also known as a carbon nanotube (CNT) forest, are a porous material that is well known for its exceptional optical absorbance property. The reflectance from a VACNT forest has been reported to be as low as 0.045% [1,2]. It is known as the darkest mate...
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Korean Carbon Society
2016
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iium-505732017-03-21T10:00:51Z http://irep.iium.edu.my/50573/ Enhancement of reflectance of densified vertically aligned carbon nanotube forests Rana, Masud M Razib, M Asyraf Saleh, Tanveer Asan Gani, Abdul Muthalif T Technology (General) Vertically aligned carbon nanotubes (VACNTs), also known as a carbon nanotube (CNT) forest, are a porous material that is well known for its exceptional optical absorbance property. The reflectance from a VACNT forest has been reported to be as low as 0.045% [1,2]. It is known as the darkest material on Earth. Because of its remarkable material properties, it has various other applications as gas sensors [3], pressure sensors [4], temperature sensors [5], and strain sensors [6]. Recently, various efforts have been made to mechanically manipulate the vertical structure of the nanotubes in the CNT forest and to conduct their optical characterization [7,8]. Optical reflection from bare VACNTs has also been investigated at different wavelengths by Wąsik et al. [9]. Controlled densification by wetting of the CNT forest is another post processing technique that has been reported by other researchers [10]. A densification process is necessary to make the CNT forest useful as a future electronics interconnect [10]. However, no study has been done so far on the optical behavior of CNT forests densified by a wetting process. In this letter, for the first time, we investigate and explain the nature of the optical reflectance of densified VACNTs. Fig. 1 illustrates how the CNT forest is able to absorb most incident light. It was reported elsewhere that VACNT arrays are highly porous [11]. As a result, when incident light enters the bare CNT forest, it goes through several internal reflection-absorption cycles via individual nanotubes and finally makes its way out of the CNT forest as shown in Fig. 1b. Hence, a very low amount of light bounces back (approximately 0.045%) [1,2]. Mathematically, a simple model can be developed to estimate the final amount of light coming out of a CNT forest after several internal reflections; this process is explained by eq (1): Korean Carbon Society 2016-04-30 Article PeerReviewed application/pdf en http://irep.iium.edu.my/50573/1/%5B67-70%5D-11.pdf application/pdf en http://irep.iium.edu.my/50573/4/50573-Enhancement%20of%20reflectance%20of%20densified%20vertically%20aligned%20carbon%20nanotube%20forests_SCOPUS.pdf Rana, Masud and M Razib, M Asyraf and Saleh, Tanveer and Asan Gani, Abdul Muthalif (2016) Enhancement of reflectance of densified vertically aligned carbon nanotube forests. Carbon Letters, 18. pp. 67-70. ISSN 1976-4251 E-ISSN 2233-4998 http://carbonlett.org/PublishedPaper/year_eachList.asp?page_url=Current_Issues 10.5714/CL.2016.18.067 |
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Online Access |
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English English |
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T Technology (General) |
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T Technology (General) Rana, Masud M Razib, M Asyraf Saleh, Tanveer Asan Gani, Abdul Muthalif Enhancement of reflectance of densified vertically aligned carbon nanotube forests |
| description |
Vertically aligned carbon nanotubes (VACNTs), also known as a carbon nanotube (CNT)
forest, are a porous material that is well known for its exceptional optical absorbance property.
The reflectance from a VACNT forest has been reported to be as low as 0.045% [1,2].
It is known as the darkest material on Earth. Because of its remarkable material properties,
it has various other applications as gas sensors [3], pressure sensors [4], temperature sensors
[5], and strain sensors [6]. Recently, various efforts have been made to mechanically manipulate
the vertical structure of the nanotubes in the CNT forest and to conduct their optical
characterization [7,8]. Optical reflection from bare VACNTs has also been investigated at
different wavelengths by Wąsik et al. [9]. Controlled densification by wetting of the CNT
forest is another post processing technique that has been reported by other researchers [10].
A densification process is necessary to make the CNT forest useful as a future electronics
interconnect [10]. However, no study has been done so far on the optical behavior of CNT
forests densified by a wetting process. In this letter, for the first time, we investigate and
explain the nature of the optical reflectance of densified VACNTs.
Fig. 1 illustrates how the CNT forest is able to absorb most incident light. It was reported
elsewhere that VACNT arrays are highly porous [11]. As a result, when incident light enters
the bare CNT forest, it goes through several internal reflection-absorption cycles via individual
nanotubes and finally makes its way out of the CNT forest as shown in Fig. 1b. Hence,
a very low amount of light bounces back (approximately 0.045%) [1,2].
Mathematically, a simple model can be developed to estimate the final amount of light
coming out of a CNT forest after several internal reflections; this process is explained
by eq (1): |
| format |
Article |
| author |
Rana, Masud M Razib, M Asyraf Saleh, Tanveer Asan Gani, Abdul Muthalif |
| author_facet |
Rana, Masud M Razib, M Asyraf Saleh, Tanveer Asan Gani, Abdul Muthalif |
| author_sort |
Rana, Masud |
| title |
Enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| title_short |
Enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| title_full |
Enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| title_fullStr |
Enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| title_full_unstemmed |
Enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| title_sort |
enhancement of reflectance of densified vertically aligned
carbon nanotube forests |
| publisher |
Korean Carbon Society |
| publishDate |
2016 |
| url |
http://irep.iium.edu.my/50573/ http://irep.iium.edu.my/50573/ http://irep.iium.edu.my/50573/ http://irep.iium.edu.my/50573/1/%5B67-70%5D-11.pdf http://irep.iium.edu.my/50573/4/50573-Enhancement%20of%20reflectance%20of%20densified%20vertically%20aligned%20carbon%20nanotube%20forests_SCOPUS.pdf |
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2023-09-18T21:11:29Z |
| last_indexed |
2023-09-18T21:11:29Z |
| _version_ |
1777411281835261952 |