Nav: Home

Antennas of flexible nanotube films an alternative for electronics

June 10, 2019

Antennas made of carbon nanotube films are just as efficient as copper for wireless applications, according to researchers at Rice University's Brown School of Engineering. They're also tougher, more flexible and can essentially be painted onto devices.

The Rice lab of chemical and biomolecular engineer Matteo Pasquali tested antennas made of "shear-aligned" nanotube films. The researchers discovered that not only were the conductive films able to match the performance of commonly used copper films, they could also be made thinner to better handle higher frequencies.

The results detailed in Applied Physics Letters advance the lab's previous work on antennas based on carbon nanotube fibers.

The lab's shear-aligned antennas were tested at the National Institute of Standards and Technology (NIST) facility in Boulder, Colorado, by lead author Amram Bengio, who carried out the research and wrote the paper while earning his doctorate in Pasquali's lab. Bengio has since founded a company to further develop the material.

At the target frequencies of 5, 10 and 14 gigahertz, the antennas easily held their own with their metal counterparts, he said. "We were going up to frequencies that aren't even used in Wi-Fi and Bluetooth networks today, but will be used in the upcoming 5G generation of antennas," he said.

Bengio noted other researchers have argued nanotube-based antennas and their inherent properties have kept them from adhering to the "classical relationship between radiation efficiency and frequency," but the Rice experiments with more refined films have proved them wrong, allowing for the one-to-one comparisons.

To make the films, the Rice lab dissolved nanotubes, most of them single-walled and up to 8 microns long, in an acid-based solution. When spread onto a surface, the shear force produced prompts the nanotubes to self-align, a phenomenon the Pasquali lab has applied in other studies.

Bengio said that although gas-phase deposition is widely employed as a batch process for trace deposition of metals, the fluid-phase processing method lends itself to more scalable, continuous antenna manufacturing.

The test films were about the size of a glass slide, and between 1 and 7 microns thick. The nanotubes are held together by strongly attractive van der Waals forces, which gives the material mechanical properties far better than those of copper.

The researchers said the new antennas could be suitable for 5G networks but also for aircraft, especially unmanned aerial vehicles, for which weight is a consideration; as wireless telemetry portals for downhole oil and gas exploration; and for future "internet of things" applications.

"There are limits because of the physics of how an electromagnetic wave propagates through space," Bengio said. "We're not changing anything in that regard. What we are changing is the fact that the material from which all these antennas will be made is substantially lighter, stronger and more resistant to a wider variety of adverse environmental conditions than copper."

"This is a great example of how collaboration with national labs greatly expands the reach of university groups," Pasquali said. "We could never have done this work without the intellectual involvement and experimental capabilities of the NIST team."
-end-
Co-authors of the paper are Rice graduate student Lauren Taylor, research group manager Robert Headrick and alumni Michael King and Peiyu Chen; Damir Senic, Charles Little, John Ladbury, Christian Long, Christopher Holloway, Nathan Orloff and James Booth, all of NIST; and former Rice faculty member Aydin Babakhani, now an associate profess or of electrical and computer engineering at UCLA. Pasquali is the A.J. Hartsook Professor of Chemical and Biomolecular Engineering, professor of chemistry and of materials science and nanoengineering. Bengio is the founder and chief operating officer of Wootz, L.L.C.

The Air Force Office of Scientific Research, the Department of Defense and a National Defense Science and Engineering Graduate Fellowship supported the research.

Read the abstract at https://aip.scitation.org/doi/full/10.1063/1.5093327.

This news release can be found online at https://news.rice.edu/2019/06/10/antennas-of-flexible-nanotube-films-an-alternative-for-electronics/

Follow Rice News and Media Relations via Twitter @RiceUNews.

Related materials:

Nanotube fibers in a jiffy: http://news.rice.edu/2018/01/11/nanotube-fibers-in-a-jiffy/

Nanotube fiber antennas as capable as copper: http://news.rice.edu/2017/10/23/nanotube-fiber-antennas-as-capable-as-copper-2/

Pasquali Research Group: https://pasquali.rice.edu

George R. Brown School of Engineering: https://engineering.rice.edu

Wiess School of Natural Sciences: https://naturalsciences.rice.edu

Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,962 undergraduates and 3,027 graduate students, Rice's undergraduate student-to-faculty ratio is just under 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for lots of race/class interaction and No. 2 for quality of life by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger's Personal Finance.

Rice University

Related Nanotubes Articles:

Nanotubes that build themselves
Researchers from Lund University in Sweden have succeeded in producing nanotubes from a single building block using so-called molecular self-recognition.
Carbon nanotubes self-assemble into tiny transistors
Carbon nanotubes can be used to make very small electronic devices, but they are difficult to handle.
'Pressure-welding' nanotubes creates ultrastrong material
MIPT's researchers investigated the possibility of 'gluing' parallel nanotubes to each other, creating a material so durable that it could withstand even the harsh conditions of the aerospace industry.
Nanotubes' 'stuffing' as is
Marianna Kharlamova (the Lomonosov Moscow State University Department of Materials Science) examined different types of carbon nanotubes' 'stuffing' and classified them according to the influence on the properties of the nanotubes.
Nanotubes are beacons in cancer-imaging technique
Strong LED light, a unique detector and targeted nanotubes combine to offer a new way to pinpoint the location of cancer tumors, according to Rice University scientists.
Nanotubes assemble! Rice introduces 'Teslaphoresis'
Rice University researchers use a modified Tesla coil to assemble nanoparticles into a wire from a distance.
'Honeycomb' of nanotubes could boost genetic engineering
Researchers have developed a new and highly efficient method for gene transfer.
Nanotubes line up to form films
Rice University researchers discover that a simple filtration technique produces wafer-scale films of highly aligned carbon nanotubes.
Nature-inspired nanotubes that assemble themselves, with precision
Berkeley Lab scientists have discovered a family of nature-inspired polymers that, when placed in water, spontaneously assemble into hollow crystalline nanotubes.
Microwaved nanotubes come up clean
Researchers use a household microwave oven to enhance the purification of carbon nanotubes.

Related Nanotubes Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#529 Do You Really Want to Find Out Who's Your Daddy?
At least some of you by now have probably spit into a tube and mailed it off to find out who your closest relatives are, where you might be from, and what terrible diseases might await you. But what exactly did you find out? And what did you give away? In this live panel at Awesome Con we bring in science writer Tina Saey to talk about all her DNA testing, and bioethicist Debra Mathews, to determine whether Tina should have done it at all. Related links: What FamilyTreeDNA sharing genetic data with police means for you Crime solvers embraced...