Carbon nanotubes

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wjfox
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Carbon nanotubes

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Nanotubes aligned in pristine condition

26th May 2021

Scientists in Japan have developed a new "dry transfer technique" for the precise positioning of carbon nanotubes.

Read more: https://www.futuretimeline.net/blog/202 ... nology.htm


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Re: Carbon nanotubes

Post by Time_Traveller »

A new material made from carbon nanotubes can generate electricity by scavenging energy from its environment
June 7, 2021

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MIT engineers have discovered a new way of generating electricity using tiny carbon particles that can create a current simply by interacting with liquid surrounding them.

The liquid, an organic solvent, draws electrons out of the particles, generating a current that could be used to drive chemical reactions or to power micro- or nanoscale robots, the researchers say.

"This mechanism is new, and this way of generating energy is completely new," says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT. "This technology is intriguing because all you have to do is flow a solvent through a bed of these particles. This allows you to do electrochemistry, but with no wires."

In a new study describing this phenomenon, the researchers showed that they could use this electric current to drive a reaction known as alcohol oxidation—an organic chemical reaction that is important in the chemical industry.
https://phys.org/news/2021-06-material- ... nging.html
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Re: Carbon nanotubes

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4 Inch Wafer of Trillions of Aligned Carbon Nanotubes
September 18, 2021 by Brian Wang
https://www.nextbigfuture.com/2021/09/4 ... tubes.html
Carbon nanotubes can be five times as energy efficient and five times faster than silicon. engineers at the University of Wisconsin–Madison can align the nanotubes for computer chips by turning them into 2D liquid crystals. They can coat an entire 4-inch wafer with a uniform array of highly aligned carbon nanotubes in 40 seconds.

A purification process produces nanotubes in solvents, or nanotube inks, which they then flow at a constant velocity and thickness over a layer of water. At the interface between the ink and water, the nanotubes begin to concentrate and self-organize, forming a liquid crystal. That liquid crystal is then transferred on a substrate moved through the ink and water interface. The result is a wafer covered in trillions of highly aligned carbon nanotubes.

The nanotube density is near that needed for electronics. They determined the alignment of the tubes to be within 6° locally. This almost ideal nanotube ordering led to excellent electrical properties that were confirmed consistent across the entire wafer.

The process is a big advance for carbon nanotube research. However, it does need some tweaks before nanotube computer processors end up in smartphones and laptops. The industry standard is 12-inch wafers, so the process, patented through the Wisconsin Alumni Research Foundation, needs to be scaled up while maintaining the uniformity of the nanotube alignment.

They can also be deposited in multiple layers, like 3D integrated circuits. That would allow us to increase the number of transistors significantly.
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andmar74
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Re: Carbon nanotubes

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Carbon nanotubes? Well..

Here's a news item from a KurzweilAI daily newsletter, august 2005:

"Large, transparent sheets of carbon
nanotubes can now be produced at
lightning speed. The new technique
should allow the nanotubes to be
used in commercial devices from
heated car windows to flexible
television screens. At team led by
Ray Baughman, a chemist from the
University of Texas at Dallas, can
churn out up to ten meters of
nanoribbon..."
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Re: Carbon nanotubes

Post by wjfox »

andmar74 wrote: Mon Sep 20, 2021 8:29 am Carbon nanotubes? Well..

Here's a news item from a KurzweilAI daily newsletter, august 2005:

"Large, transparent sheets of carbon
nanotubes can now be produced at
lightning speed. The new technique
should allow the nanotubes to be
used in commercial devices from
heated car windows to flexible
television screens. At team led by
Ray Baughman, a chemist from the
University of Texas at Dallas, can
churn out up to ten meters of
nanoribbon..."

There's a big difference between lab work and mass commercialisation.

A lot of progress has occurred since then, however:

https://en.wikipedia.org/wiki/Carbon_na ... plications

"A primary obstacle for applications of carbon nanotubes has been their cost. Prices for single-walled nanotubes declined from around $1500 per gram as of 2000 to retail prices of around $50 per gram of as-produced 40–60% by weight SWNTs as of March 2010. As of 2016, the retail price of as-produced 75% by weight SWNTs was $2 per gram."
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Re: Carbon nanotubes

Post by Doozer »

I imagine that graphene-related tech (which includes carbon nanotubes) will become ubiquitous by 2029. At least on an industrial-level.
weatheriscool
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Re: Carbon nanotubes

Post by weatheriscool »

Carbon nanotube–based MOSFETs doped using a scalable technique
https://techxplore.com/news/2023-11-car ... lable.html
by Ingrid Fadelli , Tech Xplore
In recent years, electronics engineers have been trying to identify materials that could help to shrink the size of transistors without compromising their performance and energy efficiency. Low-dimensional semiconductors, solid-state superconducting materials with fewer than three spatial dimensions, could help to achieve this.

Among low-dimensional semiconducting materials that have been found to be particularly promising for reducing the length of gates inside transistors are one-dimensional (1D) carbon nanotubes. Nonetheless, most proposed strategies to dope these materials and control the polarity inside them are not compatible with existing large-scale electronics production methods.
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Re: Carbon nanotubes

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New ways to make ordered wafer-scale chiral carbon nanotube architectures
https://phys.org/news/2023-12-ways-wafe ... otube.html
by Silvia Cernea Clark, Rice University
Chiral materials interact with light in very precise ways that are useful for building better displays, sensors and more powerful devices. However, engineering properties such as chirality reliably at scale is still a significant challenge in nanotechnology.

Rice University scientists in the lab of Junichiro Kono have developed two ways of making wafer-scale synthetic chiral carbon nanotube (CNT) assemblies starting from achiral mixtures. According to a study published in Nature Communications, the resulting "tornado" and "twisted-and-stacked" thin films can control ellipticity—a property of polarized light—to a level and in a range of the spectrum that was previously largely beyond reach.

"These approaches have granted us the ability to deliberately and consistently introduce chirality to materials that, until now, did not exhibit this property on a macroscopic scale," said Jacques Doumani, a graduate student in applied physics at Rice and the lead author of the study. "Our methods yield thin, flexible films with tunable chiral properties."

CNTs—hollow cylindrical structures made from carbon atoms—possess remarkable electrical, mechanical, thermal and optical properties. A single-wall CNT has a diameter approximately 100,000 times smaller than that of a single human hair.
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