Nav: Home

Researchers discover semiconducting nanotubes that form spontaneously

July 08, 2019

If scientists could find a way to control the process for making semiconductor components on a nanometric scale, they could give those components unique electronic and optical properties - opening the door to a host of useful applications.

Researchers at the Laboratory of Microsystems, in EPFL's School of Engineering, have taken an important step towards that goal with their discovery of semiconducting nanotubes that assemble automatically in solutions of metallic nanocrystals and certain ligands. The tubes have between three and six walls that are perfectly uniform and just a few atoms thick - making them the first such nanostructures of their kind.

What's more, the nanotubes possess photoluminescent properties: they can absorb light of a specific wavelength and then send out intense light waves of a different color, much like quantum dots and quantum wells. That means they can be used as fluorescent markers in medical research, for example, or as catalysts in photoreduction reactions, as evidenced by the removal of the colors of some organic dyes, based on the results of initial experiments. The researchers' findings have made the cover of ACS Central Science.

An accidental discovery

But the unique feature of these semiconducting nanotubes is how they are formed. "Our discovery happened almost by chance. We had set out to study the role that certain ligands play in making 2D semiconducting nanometric crystals," says Xiaopeng Huang, the study's lead author. But the research team found that some ligands caused molecules to spontaneously come together in precise cylindrical structures which until then had been impossible to create.

Investigating new properties

The researchers will now investigate the other physical and electrical properties of their nanotubes and look into methods for making nanotubes with just a single wall.
-end-
References

Xiaopeng Huang, Virendra K. Parashar and Martin A.M. Gijs, "Spontaneous Formation of CdSe Photoluminescent Nanotubes with Visible-light Photocatalytic Performance," ACS Central Science. DOI: 10.1021/acscentsci.9b00184

Ecole Polytechnique Fédérale de Lausanne

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

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...