Tag Archives: C60 fullerenes

The birth of carbon nanotubes (CNTs): a history

There is a comprehensive history of the carbon nanotube stretching back to prehistory and forward to recent times in a June 3, 2016 Nanowerk Spotlight article by C.K. Nisha and Yashwant Mahajan of the Center of Knowledge Management of Nanoscience & Technology (CKMNT) in India. The authors provide an introduction explaining the importance of CNTs,

Carbon nanotubes (CNTs) have been acknowledged as the material of the 21st century. They possess unique combination of extraordinary mechanical, electronic, transport, electrical and optical, properties and nanoscale sizes making them suitable for a variety of applications ranging from engineering, electronics, optoelectronics, photonics, space, defence industry, medicine, molecular and biological systems and so on and so forth. Worldwide demand for CNTs is increasing at a rapid pace as applications for the material are being matured.

According to MarketsandMarkets (M&M), the global market for carbon nanotubes in 2015 was worth about $2.26 billion1; an increase of 45% from 2009 (i.e. ~ $ 1.24 billion). This was due to the growing potential of CNTs in electronics, plastics and energy storage applications and the projected market of CNTs is expected to be around $ 5.64 billion in 2020.

In view of the scientific and technological potential of CNTs, it is of immense importance to know who should be credited for their discovery. In the present article, we have made an attempt to give a glimpse into the discovery and early history of this fascinating material for our readers. Thousands of papers are being published every year on CNTs or related areas and most of these papers give credit for the discovery of CNTs to Sumio Iijima of NEC Corporation, Japan, who, in 1991, published a ground-breaking paper in Nature reporting the discovery of multi-walled carbon nanotubes (MWCNTs)2. This paper has been cited over 27,105 times in the literature (as on January 12, 2016, based on Scopus database). This discovery by Iijima has triggered an avalanche of scientific publications and catapulted CNTs onto the global scientific stage.

Nisha and Mahajan then prepare to take us back in time,

In a guest editorial for the journal Carbon, Marc Monthioux and Vladimir L. Kuznetsov3 have tried to clear the air by describing the chronological events that led to the discovery of carbon nanotubes. As one delves deeper into the history of carbon nanotubes, it becomes more apparent that the origin of CNTs could be even pre-historic in nature.

Recently, Ponomarchuk et al from Russia have reported the presence micro and nano carbon tubes in igneous rocks formed about 250 million years ago4-7. They suggested the possibility of formation of carbon nanotubes during the magmatic processes. It is presumed that the migration of hydrocarbon fluids through the residual melt of the rock groundmass created gas-saturated areas (mostly CH4, CO2, CO) in which condensation and decomposition of hydrocarbon in presence of metal elements resulted in the formation of micro and sub-micron carbon tubes.

Another most compelling evidence of pre-historic naturally occurring carbon nanotubes (MWCNTs) is based on the TEM studies carried out by Esquivel and Murr8 that analyzed 10,000-year-old Greenland ice core samples and it was suggested that probably they could have been formed during combustion of natural gas/methane during natural processes.

However, the validity of this evidence is questionable owing to the lack of clear high-resolution TEM images, high-quality diffraction patterns or Raman spectroscopy data. In addition, [an]other interesting possibility is that the carbon nanotubes could have been directly formed by the transformation of naturally occurring C60 fullerenes in nature without the assistance of man, given the right conditions prevail. Suchanek et al.,9 have actually demonstrated this thesis, under the laboratory environment, by transforming C60 fullerenes into CNTs under hydrothermal conditions.

There is a large body of evidence in literature about the existence of naturally occurring fullerenes in nature, e.g., coal, carboneous rocks, interstellar media, etc. Since the above experiments were conducted under the simulated geological environment, their results imply that CNTs may form in natural hydrothermal environment.

This hypothesis was further corroborated by Velasco-Santos and co-workers10, when they reported the presence of CNTs in a coal–petroleum mix obtained from an actual oil well, identified by the PEMEX (the Mexican Petroleum Company) as P1, which is located in Mexico’s southeast shore. TEM studies revealed that the coal-petroleum mix contained predominantly end-capped CNTs that are nearly 2 µm long with outer diameter varying between few to several tenths of nanometers.

There’s another study supporting the notion that carbon nanotubes may be formed naturally,

In yet another study, researchers from Germany11 have synthesized carbon nanotubes using igneous rock from Mount Etna lava as both support and catalyst. The naturally occurring iron oxide particles present in Etna lava rock make it an ideal material for growing and immobilizing nanocarbons.

When a mixture of ethylene and hydrogen were passed over the pulverized rocks reduced in a hydrogen atmosphere at 700°C, the iron particles catalyzed the decomposition of ethylene to elemental carbon, which gets deposited on the lava rock in the form of tiny tubes and fibers.
This study showed that if a carbon source is available, CNTs/CNFs can grow on a mineral at moderate temperatures, which directs towards the possibilities of carbon nanotube formation in active suboceanic volcanos or even in interstellar space where methane, atomic hydrogen, carbon oxides, and metallic iron are present.

This fascinating and informative piece was originally published in the January 2016 edition of Nanotech Insights (CKMNT newsletter; scroll down) and can be found there although it may be more easily accessible as the June 3, 2016 Nanowerk Spotlight article where it extends over five (Nanowerk) pages and has a number of embedded images along with an extensive list of references at the end.

Enjoy!

Year of Nano at Rice University

I mentioned the Year of Nano 25th anniversary celebration of the buckminsterfullerene (also known as a C60 fullerene or bucky ball) at Rice University in a Feb. 8, 2010 posting (it’s towards the bottom) and wasn’t really expecting to hear more about it until the technical symposium in October 2010. Yesterday, the folks at Rice University sent out a news release that manages to herald both the Year of Nano and the 50th anniversary of the laser. From the news release (titled, From beams to bucky balls),

Twenty-five years after the laser beam came to be, a historic meeting took place at Rice University that led to the discovery of the buckminsterfullerene, the carbon 60 molecule for which two Rice scientists won the Nobel Prize.

Now that the buckyball is celebrating its own 25th anniversary, it’s worth noting that one wouldn’t have happened without the other.

During the Year of Nano, Rice will honor Nobel laureates Robert Curl and the late Richard Smalley, their research colleague and co-laureate, Sir Harold Kroto, then of the University of Sussex, and former graduate students James Heath and Sean O’Brien with a series of events culminating in an Oct. 11-13 symposium at Rice on nanotechnology’s past, present and future.

But Curl happily throws a share of the credit to another Rice professor, Frank Tittel, a laser pioneer whose work continues to break new ground in chemical sensing.

Fifty years ago this Sunday, on May 16, 1960, Hughes Research scientist Theodore Maiman fired off the first laser beam from a small ruby rod, a camera flashlamp and a power supply.

Not long after the news was reported in the New York Times, Tittel, now Rice’s J.S. Abercrombie Professor in Electrical and Computer Engineering, was asked by his new bosses at General Electric to recreate Maiman’s device. “That used brute force,” Tittel said of his first laser, later donated to the Franklin Institute Science Museum in Philadelphia. “Now we’re more sophisticated.”

Tittel joined Rice in 1967 and quickly built the first tunable laser in Texas, used in spectroscopy and sensing devices. He also formed collaborations with other professors, including Curl, who is now Rice’s University Professor Emeritus and Kenneth S. Pitzer-Schlumberger Professor Emeritus of Natural Sciences.

The laser attracted a lot of interest and was used to investigate a number of phenomena including Kroto’s chief interest in 1985, the “abundance of carbon molecules in interstellar clouds,”

…  The experiments in late 1985 showed an abundance of carbon 60, which set the scientists racing to figure out what such a molecule would look like. “We had this problem that this (carbon cluster) was a little strong, and it looked like there was something there,” Curl said, noting that the team pursued the interstellar question no further. “The discovery of the fullerenes drew all our attention.”

Smalley was the first to find the solution by assembling a paper model of hexagons and pentagons that turned out to be identical to a soccer ball. (In a webcast available here, Curl described how the team came up with the key to the solution over enchiladas at a Houston diner.)

The webcast with Curl is titled, How Astrophysical Interests Accidentally Led to Advances in Carbon Chemistry. I think what’s so fascinating is that Richard Smalley wasn’t that interested in Kroto’s question but it was that question that led to their great discovery. This story reminded me of a comment from Dr. J. Storrs Hall that I quoted in one of my recent posts (scroll down to find the passage), “As Dr. Hall aptly noted it’s not dispassionate calculations but ‘serendipity: the way science always works’.”