Selected RSS news

The potentially world-changing research that no one knows about

Imagine that there exists a two-dimensional (single-layer) crystal that is made of a commonly available element, is stronger than steel yet lighter weight and flexible, displays ballistic electron mobility (for comparison, two orders of magnitude greater mobility than silicon, at room temperature), and is sufficiently optically active to see with the naked eye (though far more practically, using an optical microscope). Prospective applications include flexible, high-speed electronic devices and new composite materials for aircraft.

Would this sound like a potentially world-changing substance worthy of scientific attention and funding?

That substance is graphene, a single layer of graphite with hexagonally arranged carbon atoms (visualized as chicken wire).

Now imagine that the mechanical properties of this substance aren’t measured yet, as was the case for graphene before 2009. Imagine further that there is no way to grow or isolate the single-layer crystals in their free state, as was the case for graphene before 2004. Stepping back in time yet further, imagine that the theoretical work predicting massless charge carrier behavior hasn’t been carried out yet, as was the case for graphene before 1984.

Peeling back these milestones, we can see that if the scientific question being asked is “What can be realized from here?” then the graphene timeline played out characteristically, with major advancements coming primarily from opportunity-based research. In other words, over 50+ years, from the initial theoretical work on graphene in 1947 until stable monolayers were achieved in 2004, there was limited vision of what end-goals might be achievable and limited drive to get there.

What happens when a different question is asked, specifically “What can be realized according to physical law?” This is the key premise of the exploratory engineering approach, a methodology proposed by Eric Drexler for assessing the capabilities of future technologies. He points out, for example, that the principles of space flight had been worked out long before science and industry advanced enough to get to actual launch.

For initial space flight development, the answers to the two questions above were dramatically different: what could be done in practice was far behind what had been established as theoretically possible, and there was no defined path between them. By identifying what was achievable according to physical law, the longer-term goal of space flight entered the consciousness of physicists, engineers, and politicians, bringing great minds and great resources to the challenge.

With the benefit of similarly future-focused knowledge, perhaps graphene might have received far more attention far sooner. Consider this: the groundbreaking experimental work that sparked the field as we know it today was the discovery that single-layer graphene could be extracted from a piece of graphite by (essentially) pressing cellophane tape against it and peeling it away. In other words, a decades-long roadblock to achievements in graphene research was not a matter of inadequate supporting technology but one of limited scientific attention.

Here graphene serves as a useful illustration of how progress could potentially be hindered when opportunity-based research is relied upon exclusively. Scientific advancement could benefit significantly from deliberate, exploratory engineering. Perhaps there are numerous other ‘graphenes’ right now, going unnoticed or under-prioritized, because we are failing to ask: what can be realized according to physical law?
-Posted by Stephanie C

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Vorbeck Materials Expands Vor-ink Capacity; Launches Online Store

Vorbeck Materials, an established leader in graphene production and engineering, announces a new online store, the completion of its latest capacity expansion, and new specialized Vor-ink products.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Assembling functional nanowire yarns with light

Nanoscale materials like quantum dots, carbon nanotubes, graphene, or nanowires, have intriguing properties, but unless they can be assembled in to larger structures it is difficult to take advantage of these properties. Figuring out how to assemble nanostructures into functional macroscale assemblies is one of the key challenges that nanoscientists around the world are faced with. In the area of nanowires, this has led to researchers exploring various nanowire assembly techniques ranging from Langmuir Blodgett alignment to electrospinning. Researchers have now developed a novel approach for assembling nanowires into macroscopic yarns that consist of millions of nanowires bundled together. The team found that light can be used to charge inorganic semiconducting nanowires. Once charged, the nanowires can be manipulated with electric fields.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

See-Through Memory Devices

Combining silicon oxide and graphene yields transparent memory devices

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

More Materials Go 2-D

Graphene is joined by a growing collection of ultrathin crystals with new properties and applications

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Visionary transparent memory a step closer to reality

Rice University making reliable 3-D memories from silicon oxide and graphene.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Measuring individual chemical bonds with noncontact-AFM

Noncontact AFM with a carbon monoxide-functionalized tip was used to image C-C bonds of different length and bond order in a nanographene molecule. The molecules used were synthesized by Centro de Investigacion en Quimica Bioloxica e Materiais Moleculares (CIQUS) at the Universidade de Santiago de Compostela and Centre National de la Recherche Scientifique (CNRS) in Toulouse. (Credit: IBM Research-Zurich)

Scanning probe microscopy (SPM) is one of the principal paths to atomically precise manufacturing (molecular manufacturing). One of the varieties of SPM that shows great promise is noncontact atomic force microscopy (NC-AFM). In a significant milestone, a team of scientists at IBM has greatly expanded the capabilities of NC-AFM by providing unprecedented information about the length and strength of individual chemical bonds within molecules. A hat tip to ScienceDaily for reprinting this IBM press release “IBM Scientists First to Distinguish Individual Molecular Bonds“:

IBM (NYSE: IBM) scientists have been able to differentiate the chemical bonds in individual molecules for the first time using a technique known as noncontact atomic force microscopy (AFM).

The results push the exploration of using molecules and atoms at the smallest scale and could be important for studying graphene devices, which are currently being explored by both industry and academia for applications including high-bandwidth wireless communication and electronic displays.

“We found two different contrast mechanisms to distinguish bonds. The first one is based on small differences in the force measured above the bonds. We expected this kind of contrast but it was a challenge to resolve,” said IBM scientist Leo Gross. “The second contrast mechanism really came as a surprise: Bonds appeared with different lengths in AFM measurements. With the help of ab initio calculations we found that the tilting of the carbon monoxide molecule at the tip apex is the cause of this contrast.”

As reported in the cover story of the September 14th issue of Science magazine [abstract], IBM Research scientists imaged the bond order and length of individual carbon-carbon bonds in C60, also known as a buckyball for its football shape and two planar polycyclic aromatic hydrocarbons (PAHs), which resemble small flakes of graphene. The PAHs were synthesized by Centro de Investigacion en Quimica Bioloxica e Materiais Moleculares (CIQUS) at the Universidade de Santiago de Compostela and Centre National de la Recherche Scientifique (CNRS) in Toulouse.

The individual bonds between carbon atoms in such molecules differ subtly in their length and strength. All the important chemical, electronic, and optical properties of such molecules are related to the differences of bonds in the polyaromatic systems. Now, for the first time, these differences were detected for both individual molecules and bonds. This can increase basic understanding at the level of individual molecules, important for research on novel electronic devices, organic solar cells, and organic light-emitting diodes (OLEDs). In particular, the relaxation of bonds around defects in graphene as well as the changing of bonds in chemical reactions and in excited states could potentially be studied.

As in their earlier research (Science 2009, 325, 1110, abstract) the IBM scientists used an atomic force microscope (AFM) with a tip that is terminated with a single carbon monoxide (CO) molecule. This tip oscillates with a tiny amplitude above the sample to measure the forces between the tip and the sample, such as a molecule, to create an image. The CO termination of the tip acts as a powerful magnifying glass to reveal the atomic structure of the molecule, including its bonds. This made it possible to distinguish individual bonds that differ only by 3 picometers or 3 × 10-12 meters, which is about one-hundredth of an atom’s diameter. …

The images made soon after AFM was invented in 1986 did not achieve atomic resolution, so the achievement of picometer-level resolution is indeed an impressive accomplishment. It will be interesting to see if greater precision in imaging will lead to greater precision in manipulation of atoms and individual chemical bonds.
—James Lewis, PhD

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Scientists differentiate chemical bonds in individual molecules for first time using noncontact atomic force microscopy

IBM scientists have been able to differentiate the chemical bonds in individual molecules for the first time using a technique known as noncontact atomic force microscopy (AFM). The results push the exploration of using molecules and atoms at the smallest scale and could be important for studying graphene devices, which are currently being explored by both industry and academia for applications including high-bandwidth wireless communication and electronic displays.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Angstron Materials to Exhibit, Deliver Technical Presentation at NanoKorea 2012

Angstron Materials Inc., will demonstrate its capability to produce ultra-thin graphene along with its technology advances for applications in graphene-based thermal dissipation sheets, nano-composites and other uses.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)

Physicists explore properties of electrons in revolutionary material

Scientists have found a new way to examine certain properties of electrons in graphene – a very thin material that may hold the key to new technologies in computing and other fields.

VN:F [1.9.17_1161]
Rating: 0.0/10 (0 votes cast)
VN:F [1.9.17_1161]
Rating: 0 (from 0 votes)
Username: 0...