scholarly journals Large Arrays and Networks of Carbon Nanotubes: Morphology Control by Process Parameters

10.5772/52674 ◽  
2013 ◽  
Author(s):  
I. Levchenko ◽  
Z.-J. Han ◽  
S. Kumar ◽  
S. Yick ◽  
J. Fang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Process Parameters ◽  
Morphology Control

Fabrication of Carbon Nanotubes Reinforced Polyethylene Fibers by Melt Spinning: Process Optimization and Mechanical Strength Characterization

2007 ◽  
Vol 26-28 ◽  
pp. 289-292
Author(s):  
Abu Bakar Sulong ◽  
Joo Hyuk Park
Keyword(s):  
Carbon Nanotubes ◽  
Process Parameters ◽  
Melt Spinning ◽  
Polymer Fibers ◽  
Test Machine ◽  
Taguchi’S Method ◽  
Spinning Process ◽  
Strength Characterization ◽  
Surface Modified ◽  
Polyethylene Fibers

Optimization process for fabrication of Carbon nanotubes (CNTs) reinforced Polyethylene (PE) fibers by melt spinning has been studied. Three main melt spinning process parameters (spinning temperature, spinning distance, and spinning revolution) are evaluated by the Taguchi’s method to decrease the diameter of fibers. Decreasing diameter of fibers is greater influenced by spinning revolution and distance than spinning temperature. Moreover, fibers in diameter 22 μm (average) are successfully fabricated. Mechanical properties are measured by tensile test machine based on ASTM D3822 for single fibers which were fabricated at optimized melt spinning process parameters. Pure PE polymer fibers and chemically surface modified CNTs reinforced fibers also fabricated for comparison purpose. The interfacial bonding of CNTs with PE matrix is investigated through fracture surfaces image analysis by Scanning Electron Microscopy (SEM).

Numerical Model of Template-Based Chemical Vapor Deposition Processes to Manufacture Carbon Nanotubes for Biological Devices

2015 ◽  
Author(s):  
Yashar Seyed Vahedein ◽  
Michael G. Schrlau
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Vapor Deposition ◽  
Process Parameters ◽  
Flow Rate ◽  
Vapor Deposition ◽  
Carbon Nanostructures ◽  
Numerical Models ◽  
Fluid Dynamic ◽  
Low Cost ◽  
Chemical Vapor

Carbon nanotubes (CNTs) hold significant promise in the fields of efficient drug delivery and bio-sensing for disease treatment because of their unique properties. In our lab, single and arrayed CNT-tipped devices are manufactured by deposition of carbon on the heated surfaces of templates using chemical vapor deposition (Template-Based Chemical Vapor Deposition, TB-CVD). Experimental results show CNT formation in templates is controlled by TB-CVD process parameters such as flow rate and temperature. However, there is a need for a more comprehensive and low cost way to characterize the flow in the furnace in order to understand how process parameters may affect CNT formation. In this report, 2D and 3D numerical models with Quadrilateral grids were developed using computational fluid dynamic (CFD) commercial codes. Velocity patterns and flow regimes in the tube were compared with experimental data. In addition, statistical techniques were employed to study temperature profiles and velocity patterns in the furnace as a function of flow rate. The outcome of this work will help to elucidate the TB-CVD process and facilitate the efficient manufacture of carbon nanostructures from a variety of templates. The results are broadly applicable to the manufacturing of CNTs and other nanostructured devices used in energy and biomedical fields, including CNT-based devices used in biological applications.

Numerical Investigation of Thermofluid Flow in a Chemical Vapor Deposition Furnace Utilized to Manufacture Template-Synthesized Carbon Nanotubes

2016 ◽  
Vol 138 (10) ◽  
Author(s):  
Yashar Seyed Vahedein ◽  
Michael G. Schrlau
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Vapor Deposition ◽  
Process Parameters ◽  
Vapor Deposition ◽  
Numerical Models ◽  
Fluid Dynamic ◽  
Low Cost ◽  
Chemical Vapor ◽  
Computational Time ◽  
Anodized Aluminum

Template-based chemical vapor deposition (TB-CVD) is a versatile technique for manufacturing carbon nanotubes (CNTs) or CNT-based devices for various applications. In this process, carbon is deposited by thermal decomposition of a carbon-based precursor gas inside the nanoscopic cylindrical pores of anodized aluminum oxide (AAO) templates to form CNTs. Experimental results show that CNT formation in templates is controlled by TB-CVD process parameters, such as time, temperature, and flow rate. However, optimization of this process is done empirically, requiring tremendous time and effort. Moreover, there is a need for a more comprehensive and low cost way to characterize the flow in the furnace in order to understand how process parameters may affect CNT formation. In this report, we describe the development of four, 3D numerical models (73 < Re < 1100), each varying in complexity, to elucidate the thermofluid behavior in the TB-CVD process. Using computational fluid dynamic (CFD) commercial codes, the four models are compared to determine how the presence of the template and boat, composition of the precursor gas, and consumption of species at the template surface affect the temperature profiles, velocity fields, mixed convection, and strength of circulations in the system. The benefits and shortcomings of each model, as well as a comparison of model accuracy and computational time, are presented. Due to limited data, simulation results are validated by experiments and visual observations of the flow structure whenever possible. Decent agreement between experimental data and simulation supports the reliability of the simulation.

Effects of alumina phases and process parameters on the multiwalled carbon nanotubes growth

2007 ◽  
Vol 16 (4-7) ◽  
pp. 1144-1149 ◽  
Author(s):  
Paolo Ciambelli ◽  
Diana Sannino ◽  
Maria Sarno ◽  
Caterina Leone ◽  
Ugo Lafont
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Process Parameters ◽  
Multiwalled Carbon

scholarly journals Synthesis of Carbon Nanotubes (CNTs) from Poultry Litter for Removal of Chromium Cr (VI) from Wastewater

2021 ◽  
Author(s):  
Noor Haleem ◽  
Yousuf Jamal ◽  
Shahid Nawaz Khan ◽  
Muhammad Anwar Baig
Keyword(s):  
Carbon Nanotubes ◽  
Process Parameters ◽  
Contact Time ◽  
Agricultural Land ◽  
Poultry Litter ◽  
Disposal Site ◽  
Thermochemical Conversion ◽  
Experimental Conditions ◽  
Environmental Application ◽  
Synthesis Of Carbon Nanotubes

Pakistan being an agricultural country is raising 146.5 million commercial and domestic poultry birds which generate around 544,831 tons of waste. This waste finds its final disposal in agricultural land as soil fertilizer or disposal site amendment. The uncontrolled use of poultry litter for this purpose results in environmental impacts such as the emission of methane, a greenhouse gas. However, other options like thermochemical conversion of this waste can offer a better solution wherein poultry litter can be used as low-cost carbon sources for the synthesis of Carbon Nanotubes (CNTs). In this study, efforts have been made to utilize this cheap and plenty of available carbon source for synthesis of CNTs in the presence of Ni/Mo/MgO as a catalyst, through pyrolysis. The optimum mole ratio of catalyst (4:0.2:1) was found to yield more carbon product. Furthermore, process parameters such as temperature, time, polymer &amp; catalyst weight were also optimized. The best possible process parameters that resulted (pyrolysis time (12 min), temperature (825◦C), and catalyst weight (100 mg) good yield of CNTs . The structure and morphology of produced nanotubes were confirmed through X-ray Diffractometer (X-RD) &amp; Scanning Electron Microscopy (SEM). The environmental application of the nanotubes was tested in synthetic chromium solution in the lab using a batch experiment. Different experimental conditions (pH, adsorbent dosage and contact time) were optimized to enhance the adsorption of Cr (VI) by carbon nanotubes and UV-Visible spectrophotometer was used at 540nm to measure the absorbance of Cr (VI). Results show that up to 81.83% of Cr (VI) removal was achieved by using 8 mg of CNTs at pH 3 with 400 rpm at 180 min of contact time. Thus, it was concluded that poultry litter can be a useful source for the synthesis of CNTs and thereby removal of Cr (VI) from industrial tanneries wastewater.

scholarly journals Quantum Dot Attachment and Morphology Control by Carbon Nanotubes

Nano Letters ◽  
2007 ◽  
Vol 7 (12) ◽  
pp. 3564-3568 ◽  
Author(s):  
Beatriz H. Juárez ◽  
Christian Klinke ◽  
Andreas Kornowski ◽  
Horst Weller
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dot ◽  
Morphology Control
Sign in / Sign up

Export Citation Format

Share Document