Growth Mechanism of Single-Walled Carbon Nanotubes from Pt Catalysts by Alcohol Catalytic CVD

2015 ◽  
Vol 1752 ◽  
pp. 27-30
Author(s):  
Takahiro Maruyama ◽  
Hiroki Kondo ◽  
Akinari Kozawa ◽  
Takahiro Saida ◽  
Shigeya Naritsuka ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Photoelectron Spectroscopy ◽  
Chemical Vapor ◽  
Pt Catalyst ◽  
Pt Catalysts ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Gas Source ◽  
Transmission Electron ◽  
Walled Carbon Nanotubes

ABSTRACTSingle-walled carbon nanotube (SWCNT) growth from Pt catalysts by an alcohol gas source method, a type of cold-wall chemical vapor deposition (CVD), was investigated. Raman results showed that the diameters of SWCNTs grown from Pt were below 1.2 nm, while transmission electron microscopy (TEM) showed that the diameters of most Pt catalyst particles were above 1.2 nm. This suggests that SWCNT diameters were smaller than Pt catalysts particles. X-ray photoelectron spectroscopy measurements showed that reduction of Pt particles occurred during the SWCNT growth. Based on these experimental data, growth mechanism of SWCNTs was discussed.

scholarly journals Discovery of carbon nanotubes in sixth century BC potteries from Keeladi, India

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Manivannan Kokarneswaran ◽  
Prakash Selvaraj ◽  
Thennarasan Ashokan ◽  
Suresh Perumal ◽  
Pathikumar Sellappan ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Average Diameter ◽  
Sixth Century ◽  
Nano Materials ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

AbstractUnique black coatings were observed in the inner wall of pottery shreds excavated from Keeladi, Tamilnadu, India. Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used to understand the nature of the coating. The analysis revealed the presence of single, multi-walled carbon nanotubes and layered sheets in the coating. The average diameter of single-walled carbon nanotube found to be about 0.6 ± 0.05 nm. This is the lowest among the single-walled carbon nanotubes reported from artefacts so far and close to the theoretically predicted value (0.4 nm). These nanomaterials were coated in the pottery’s that date backs to sixth century BC, and still retain its stability and adhesion. The findings of nano materials in the pre-historic artifacts, its significance and impact are discussed in this article.

Vertically Aligned Single-Walled Carbon Nanotube Growth from Ir Catalysts by Alcohol Gas Source Method

MRS Advances ◽  
2019 ◽  
Vol 4 (3-4) ◽  
pp. 225-230
Author(s):  
Takuya Okada ◽  
Takahiro Saida ◽  
Shigeya Naritsuka ◽  
Takahiro Maruyama
Keyword(s):  
Chemical Vapor ◽  
Growth Time ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Si Substrates ◽  
Gas Source ◽  
Vertically Aligned ◽  
Carbon Nanotube Growth ◽  
Nanotube Growth ◽  
Walled Carbon Nanotubes

Abstract:We demonstrated that single-walled carbon nanotubes (SWCNTs) grew from Ir catalysts by an alcohol catalytic chemical vapor deposition (ACCVD) method using a gas source-type CVD system. At an ethanol pressure of 1×10−1 Pa at 800°C, vertically aligned SWCNTs (VA-SWCNTs) were grown on SiO2/Si substrates. As the growth time became longer, the VA-SWCNT became thicker, and it reached almost 5 μm for a growth time of 180 min. The Raman spectroscopy results showed that the diameters of the grown SWCNTs were mainly distributed below 1.1 nm, indicating that the SWCNTs grown from Ir catalysts had small diameters compared with those from other metal catalysts.

scholarly journals Low Temperature Growth of Single-Walled Carbon Nanotubes from Pt Catalysts under Low Ethanol Pressure by Alcohol Gas Source Method

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Hiroki Kondo ◽  
Naoya Fukuoka ◽  
Takahiro Maruyama
Keyword(s):  
Carbon Nanotubes ◽  
High Vacuum ◽  
Single Walled Carbon Nanotubes ◽  
Average Diameter ◽  
Diameter Distribution ◽  
Pt Catalysts ◽  
Single Walled Carbon ◽  
Source Method ◽  
Gas Source ◽  
Walled Carbon Nanotubes

Growth of single-walled carbon nanotubes (SWNTs) was carried out on SiO2/Si substrates with Pt catalysts at 400, 450, and 700°C under various ethanol pressures using an alcohol gas source method in a high vacuum, and the grown SWNTs were characterized by scanning electron microscopy (SEM) and Raman spectroscopy. Irrespective of the growth temperature, both G band and RBM peaks were observed in the Raman spectra under the optimal ethanol pressure (~1×10−3Pa), indicating that SWNTs grew below 450°C from Pt. At 400°C, both average diameter and diameter distribution were drastically reduced, and those were fairly smaller and narrower, compared to those for SWNTs grown with Co.

Effects of Al2O3 Type on Activity of Al2O3-Supported Rh Catalysts in Single-Walled Carbon Nanotubes Growth by CVD

MRS Advances ◽  
2017 ◽  
Vol 2 (02) ◽  
pp. 89-95
Author(s):  
Hoshimitsu Kiribayashi ◽  
Takayuki Fujii ◽  
Takahiro Saida ◽  
Shigeya Naritsuka ◽  
Takahiro Maruyama
Keyword(s):  
Ultra Violet ◽  
Single Walled Carbon Nanotubes ◽  
Buffer Layers ◽  
Particle Sizes ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Surface Migration ◽  
Rh Catalyst ◽  
Walled Carbon Nanotubes

ABSTRACT We carried out single-walled carbon nanotube (SWCNT) growth using a Rh catalyst on Al2O3 buffer layers that were prepared by three different methods based on electron beam (EB) evaporation: native oxidation of Al layer deposited by EB ([EB(Al)+NO]-Al2O3 layer); thermal oxidation of Al layer deposited by EB ([EB(Al)+TO]-Al2O3 layer); EB deposition of Al2O3 layer ([EB(Al2O3)]-Al2O3 layer). SWCNT yield was the largest for the [EB(Al2O3)]-Al2O3 layer, while SWCNTs were not grown on the [EB(Al)+NO]- Al2O3 layer. Transmission electron spectroscopy showed that most of Rh particle sizes were distributed between 1.0 and 2.6 nm on the [EB(Al)+NO]- Al2O3 and [EB(Al2O3)]- Al2O3 layers, while they were distributed between 1.8 and 4.2 nm on the [EB(Al)+TO]- Al2O3 layer. This result indicates that surface migration of Rh catalysts was suppressed on the [EB(Al2O3)]- Al2O3 layer, resulting in the largest SWCNT yield. On the other hand, enlargement of Rh catalyst particles occurred on the [EB(Al)+TO]- Al2O3 layer, leading to the reduction of SWCNT yield. Taking into account our previous study, inward diffusion of Rh catalysts into the Al2O3 buffer layer inhibited SWCNT growth on the [EB(Al)+NO]- Al2O3 layer, although enlargement of Rh particle size was suppressed. We also carried out ultra-violet photoemission measurements for Rh catalysts on the [EB(Al)+TO]- Al2O3 and [EB(Al2O3)]- Al2O3 layers and investigated the electronic states of Rh catalysts on them.

Efficient Synthesis of Individual Single-Walled Carbon Nanotube by Water-Based Catalyst with Poly(vinylpyrrolidone)

2008 ◽  
Vol 8 (1) ◽  
pp. 329-334 ◽  
Author(s):  
Seung Yol Jeong ◽  
Sang Hyun Jeon ◽  
Gang Hee Han ◽  
Kay Hyeok An ◽  
Dong Jae Bae ◽  
...  
Keyword(s):  
Active Sites ◽  
Field Effect Transistors ◽  
Chemical Vapor ◽  
Average Diameter ◽  
Water Soluble ◽  
Excitation Energies ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
The Individual ◽  
Walled Carbon Nanotubes

Individual single-walled carbon nanotubes (SWCNTs) were synthesized on the patterned water-soluble catalyst by thermal chemical vapor deposition. The individual SWCNTs were obtained by introducing polyvinylpyrrolidone (PVP) as a dispersant. The number of SWCNTs between two electrodes were approximately 1 ∼2 with an average diameter of about 1.7 nm and a yield of forming electrodes of nearly 70%. The PVP played an important role in dispersing catalysts and suppressing the active sites to limit the number of SWCNTs during synthesis, which is a critical condition for fabrication of field effect transistors (FETs). The measured I–V characteristics of the over layer-deposited electrodes revealed a clear gating effect in large portion, in good agreement with Raman observations in several excitation energies. The patterning procedure, catalyst preparation, and growth condition for fabrication of the SWCNT-FET were further discussed.

scholarly journals GeTe-filled Carbon Nanotubes for Data Storage Applications

2010 ◽  
Vol 1251 ◽  
Author(s):  
Cristina E. Giusca ◽  
Vlad Stolojan ◽  
Jeremy Sloan ◽  
Hidetsugu Shiozawa ◽  
Ravi Silva
Keyword(s):  
Carbon Nanotubes ◽  
Data Storage ◽  
Photoelectron Spectroscopy ◽  
Memory Storage ◽  
Filling Material ◽  
Structural Investigations ◽  
Storage Devices ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Walled Carbon Nanotubes

AbstractBy virtue of their unique electronic properties, nanometer-diameter sized single-walled carbon nanotubes represent ideal candidates to function as active parts of nanoelectronic memory storage devices. We show for the first time that GeTe, a phase change material, currently considered to be one of the most promising materials for data-storage applications, can efficiently be encapsulated within single-walled carbon nanontubes of 1.4 nm diameter. Structural investigations on the encapsulated GeTe nanowires have been carried out by high resolution transmission electron microscopy. The electronic interactions between the filling material and the host nanotube have been examined using ultraviolet photoelectron spectroscopy experiments and show that the electronic structure of the encapsulating nanotube and that of the encased filling are not perturbed by the presence of each of the other component.The newly formed hybrids offer potential to operate as active elements in non-volatile electronic memory storage devices.

Purification of single-walled carbon nanotubes synthesized by the hydrogen arc-discharge method

2001 ◽  
Vol 16 (9) ◽  
pp. 2526-2529 ◽  
Author(s):  
Pengxiang Hou ◽  
Chang Liu ◽  
Yu Tong ◽  
Shitao Xu ◽  
Min Liu ◽  
...  
Keyword(s):  
Arc Discharge ◽  
Simple Procedure ◽  
Metal Particles ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Laser Raman ◽  
Transmission Electron ◽  
Resonant Laser ◽  
Walled Carbon Nanotubes ◽  
Discharge Method

A simple procedure for the purification of the single-walled carbon nanotube (SWNT) product synthesized by the hydrogen arc-discharge method was proposed and discussed. The procedure involves ultrasonication in alcohol, oxidation in fixed air, and soaking in hydrochloric acid. Most of the amorphous carbon and carbon nanoparticles as well as metal particles in the product was successfully removed, according to the results obtained from transmission electron microscopy, thermogravimetric analysis, and resonant laser Raman measurements. With this procedure, a 41 wt% yield of the SWNTs with a purity of about 96% was achieved after purification.

scholarly journals Synthesis and Optical Characterization of Sulfonated Polyaniline/Single-Walled Carbon Nanotube/Zinc Sulphide Nanocomposite

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Rajesh K. Agrawalla ◽  
Rima Paul ◽  
Amit K. Chakraborty ◽  
Apurba K. Mitra
Keyword(s):  
Visible Region ◽  
Zinc Sulphide ◽  
Luminescent Material ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Carboxylic Groups ◽  
Walled Carbon Nanotubes ◽  
Sulfonated Polyaniline

Polyaniline functionalized with sulfonate groups (SPANI) shows excellent solubility in water. Single-walled carbon nanotubes functionalized with carboxylic groups (f-SWCNTs) and then hybridized with freshly prepared zinc sulphide (ZnS) nanocrystals have been found to be good luminescent material with tuned emission properties. Nanocomposite of sulfonated polyaniline with embedded SWCNT/ZnS nanohybrid fibers has been prepared by a simple solution mixing process and characterized by using high resolution transmission electron microscopy (HRTEM), X-ray diffractometry, Raman spectroscopy, FTIR spectroscopy, and thermogravimetric analysis (TGA). The study of optical properties by UV-vis absorption and photoluminescence spectroscopy reveals that the composite is a luminescent material of enhanced emission intensity in the visible region of the spectrum.

Sign in / Sign up

Export Citation Format

Share Document