Effect of acetylene concentration and thermal ramping rate on the growth of spin-capable carbon nanotube forests

Spin-capable multiwalled carbon nanotube (MWCNT) forests that can form webs, sheets, and yarns provide a promising means for advancing various technologies. It is necessary to understand the critical factors to grow spin-capable carbon nanotubes (CNTs) in a repeatable fashion. Here we show how both the spinning capability and morphology of MWCNT forests are significantly changed by controlling the C2H2 concentration and ramp rate of temperature. The acetylene gas flow was varied in the range of 0.25–6.94% by volume. The MWCNTs grown at C2H2 concentrations between 1.47–3.37% are well-aligned and become spin-capable. The well-aligned forests have higher areal density and shorter distance between CNTs. The thermal ramp rate was also changed from 30 °C/min to 70 °C/min. A specific range of thermal ramp rate is also required to have the suitably sized nanoparticles with sufficient density resulting in higher CNT areal density for spinnable MWCNTs. A ramp rate of 50 °C/min forms suitable sized nanoparticles with sufficient density to produce CNT forests with a higher areal density and a shorter tube spacing.Spin-capable multiwalled carbon nanotube (MWCNT) forests that can form webs, sheets, and yarns provide a promising means for advancing various technologies. It is necessary to understand the critical factors to grow spin-capable carbon nanotubes (CNTs) in a repeatable fashion. Here we show how both the spinning capability and morphology of MWCNT forests are significantly changed by controlling the C2H2 concentration and ramp rate of temperature. The acetylene gas flow was varied in the range of 0.25–6.94% by volume. The MWCNTs grown at C2H2 concentrations between 1.47–3.37% are well-aligned and become spin-capable. The well-aligned forests have higher areal density and shorter distance between CNTs. The thermal ramp rate was also changed from 30 °C/min to 70 °C/min. A specific range of thermal ramp rate is also required to have the suitably sized nanoparticles with sufficient density resulting in higher CNT areal density for spinnable MWCNTs. A ramp rate of 50 °C/min forms suitable sized nanoparticles wit...

[1]  V. Shanov,et al.  Spinning yarn from long carbon nanotube arrays , 2011 .

[2]  S. Hawkins,et al.  Carbon Nanotube Webs: A Novel Material for Sensor Applications , 2011, Advanced materials.

[3]  Carter S. Haines,et al.  Biscrolling Nanotube Sheets and Functional Guests into Yarns , 2011, Science.

[4]  S. Safa,et al.  Growth of Vertically Aligned Carbon Nanotubes by DCPECVD System and the Effects of C2H2 Concentration and Plasma Current on the Growth Behavior of CNTs , 2011 .

[5]  Suguru Noda,et al.  Millimeter-tall single-walled carbon nanotubes rapidly grown with and without water. , 2011, ACS nano.

[6]  Gil S. Lee,et al.  The effects of pre-annealing in either H2 or He on the formation of Fe nanoparticles for growing spin-capable carbon nanotube forests , 2010 .

[7]  Arava Leela Mohana Reddy,et al.  Coaxial MnO2/carbon nanotube array electrodes for high-performance lithium batteries. , 2009, Nano letters.

[8]  K. Hata,et al.  Exploring advantages of diverse carbon nanotube forests with tailored structures synthesized by supergrowth from engineered catalysts. , 2009, ACS nano.

[9]  Zhennan Gu,et al.  Growth of manganese oxide nanoflowers on vertically-aligned carbon nanotube arrays for high-rate electrochemical capacitive energy storage. , 2008, Nano letters.

[10]  Shoushan Fan,et al.  Controlled growth of super-aligned carbon nanotube arrays for spinning continuous unidirectional sheets with tunable physical properties. , 2008, Nano letters.

[11]  Lianxi Zheng,et al.  Strong carbon-nanotube fibers spun from long carbon-nanotube arrays. , 2007, Small.

[12]  M. Panhuis.  Carbon nanotubes: enhancing the polymer building blocks for intelligent materials , 2006 .

[13]  J. Kong,et al.  Spinning and Processing Continuous Yarns from 4‐Inch Wafer Scale Super‐Aligned Carbon Nanotube Arrays , 2006 .

[14]  E. Sacher,et al.  Surface diffusion and coalescence of mobile metal nanoparticles. , 2005, The journal of physical chemistry. B.

[15]  K. R. Atkinson,et al.  Multifunctional Carbon Nanotube Yarns by Downsizing an Ancient Technology , 2004, Science.