Electromagnetic Properties of Graphene-Boron Nitride Materials

Houston, TX (Scicasts) — Developing novel materials from the atoms up goes faster when some of the trial and error is eliminated. A new Rice University and Montreal Polytechnic study aims to do that for graphene and boron nitride hybrids.

Rice materials scientist Rouzbeh Shahsavari and Farzaneh Shayeganfar, a postdoctoral researcher at Montreal Polytechnic, designed computer simulations that combine graphene, the atom-thick form of carbon, with either carbon or boron nitride nanotubes.

Their hope is that such hybrids can leverage the best aspects of their constituent materials. Defining the properties of various combinations would simplify development for manufacturers who want to use these exotic materials in next-generation electronics. The researchers found not only electronic but also magnetic properties that could be useful.

Their results appear in the journal Carbon.

Shahsavari’s lab studies materials to see how they can be made more efficient, functional and environmentally friendly. They include macroscale materials like cement and ceramics as well as nanoscale hybrids with unique properties.

“Whether it’s on the macro- or microscale, if we can know specifically what a hybrid will do before anyone goes to the trouble of fabricating it, we can save cost and time and perhaps enable new properties not possible with any of the constituents,” Shahsavari said.

His lab’s computer models simulate how the intrinsic energies of atoms influence each other as they bond into molecules. For the new work, the researchers modeled hybrid structures of graphene and carbon nanotubes and of graphene and boron nitride nanotubes.

“We wanted to investigate and compare the electronic and potentially magnetic properties of different junction configurations, including their stability, electronic band gaps and charge transfer,” he said. “Then we designed three different nanostructures with different junction geometry.”

Two were hybrids with graphene layers seamlessly joined to carbon nanotubes. The other was similar but, for the first time, they modeled a hybrid with boron nitride nanotubes. How the sheets and tubes merged determined the hybrid’s properties. They also built versions with nanotubes sandwiched between graphene layers.

Graphene is a perfect conductor when its atoms align as hexagonal rings, but the material becomes strained when it deforms to accommodate nanotubes in hybrids. The atoms balance their energies at these junctions by forming five-, seven- or eight-member rings. These all induce changes in the way electricity flows across the junctions, turning the hybrid material into a valuable semiconductor.

The researchers’ calculations allowed them to map out a number of effects. For example, it turned out the junctions of the hybrid system create pseudomagnetic fields.

“The pseudomagnetic field due to strain was reported earlier for graphene, but not these hybrid boron nitride and carbon nanostructures where strain is inherent to the system,” Shahsavari said. He noted the effect may be useful in spintronic and nano-transistor applications.

“The pseudomagnetic field causes charge carriers in the hybrid to circulate as if under the influence of an applied external magnetic field,” he said. “Thus, in view of the exceptional flexibility, strength and thermal conductivity of hybrid carbon and boron nitride systems, we propose the pseudomagnetic field may be a viable way to control the electronic structure of new materials.”

All the effects serve as a road map for nanoengineering applications, Shahsavari said.

“We’re laying the foundations for a range of tunable hybrid architectures, especially for boron nitride, which is as promising as graphene but much less explored,” he said. “Scientists have been studying all-carbon structures for years, but the development of boron nitride and other two-dimensional materials and their various combinations with each other gives us a rich set of possibilities for the design of materials with never-seen-before properties.”

Shahsavari is an assistant professor of civil and environmental engineering and of materials science and nanoengineering.

Graphene 3D Lab Inc. (TSXV:GGG) Introduces Graphene Flex Foam Product

Graphene 3D Lab Inc. (TSXV: GGG) (“Graphene 3D” or the “Company”) is pleased to announce the release of a new commercial product ‘Graphene Flex Foam’, a Multilayer Freestanding Flexible Graphene Foam. This material is a combination of highly conductive three-dimensional Chemical Vapor Disposition (“CVD”) ultra-light graphene foam and conductive elastomer composite.

“We have the ability to manufacture Graphene Flex Foam in basically any shape or size, but it is the flexibility of the product which we believe will capture the attention of innovative manufacturers who will want to evaluate the potential of commercializing this material into their products.” stated Elena Polyakova, Co-CEO of Graphene 3D. “Any company interested in a freestanding, stable, ultralight, highly conductive material that can flex with their product and fit into any space, will be interested in this innovation.”

This revolutionary product preserves all the remarkable properties of graphene foam such as superior electrical, with an added remarkable flexibility and ease of handling in an extremely lightweight and highly porous architecture.

“Graphene Flex Foam is an excellent substrate candidate in the manufacture of electrodes of lithium-ion batteries.” said Daniel Stolyarov, Co-CEO of Graphene 3D. “Wearable electronics is an obvious application as the electronics, sensors and conductive properties will all need to be flexible with the wearable material. “We also believe that this innovative product has a bright future for the next generation of flexible batteries and supercapacitors. Graphene Flex Foam offers energy storage as well as catalyst support in numerous organic synthesis reactions, gas sensors, flexible and ultrasonic acoustic device fabrication.”

The product will be available through Graphene Supermarket(r), an e-commerce site operated by Graphene Laboratories. Graphene 3D is currently acquiring Graphene Laboratories as a wholly-owned subsidiary (see new release dated August 24, 2015).

Read more

Angstron Increasing Graphene Production From 300 to 1000 Tonnes

During remarks at GrapChina 2015 in Qingdao, China, Dr. Bor Jang, chief executive officer and co-founder of Angstron Materials Inc. (AMI) unveiled a two-pronged plan he says will raise production capacity and lower pricer, jump starting market growth.

“We are ramping up production of graphene from 300 metric tons a year to 1000 metric tons a year in 2016,” says Jang. “Inability to source commercial scale quantities of graphene has historically hampered the growth and implementation of graphene-enabled and graphene-enhanced applications such as next-generation energy technologies, composites, water treatment, and corrosion protection. Increased production means we can bring market costs down too, giving companies previously priced out of the graphene market access to the material’s unique performance advantages.”

Read more

Graphene Materials Company Talga Resources Ltd. and Tata Steel UK Ltd. Sign Deal

Advanced materials company, Talga Resources Ltd (ASX: TLG or Talga), is pleased to advise that is has signed a Collaboration Agreement (“Agreement”) with Tata Steel UK Limited (“Tata”) to jointly explore opportunities across graphene supply, processing and development of graphene applications.

Highlights of Talga Resources Ltd. (ASX:TLG) Partnership with Tata Steel UK Ltd.:

  • Formal collaboration agreement executed with UK steel arm of global conglomerate Tata Group
  • Links Talga’s emerging industrial scale graphene production to Tata’s growing large volume graphene coating innovations
  • Graphene and graphitic carbon nano-materials from Talga pilot production to supply Tata coatings product development across diverse applications
  • Supports Talga’s focus on graphene additives for the global paint & coatings market currently consuming >40 Mt of materials per annum

Initial work will see Talga supply graphene and graphitic carbon materials for use across applications in various Tata research programs including, but not limited to, anti-corrosion pigments and conductive, formable, barrier and thermal coatings.

Read more

PEN Inc. (OTCQB:PENC) Develops Graphene-Based Product for Use in Medical Imaging

PEN Inc. (OTCQB: PENC) (“PEN” or “the Company”), a global leader in enhanced performance products enabled by nanotechnology to solve everyday problems, today announced the launch of a new graphene-based product for use in the production of nuclear pharmaceuticals used as diagnostic imaging biomarkers. Patients are given these pharmaceuticals when undergoing Positron Emission Tomography (PET) which is a molecular imaging system that provides clinicians detailed information about diseases such as cancer, neurological disorders and cardiovascular disease.

The new product is a thin carbon foil made of layers of graphene for use in cyclotron accelerators that produce nuclear pharmaceuticals. Developed at the Company’s Applied Nanotech Inc. subsidiary in Austin, Texas, the new graphene foils were part of a DOE Phase II SBIR effort to develop carbon foils for next generation ion beam accelerators. The graphene foils can serve as either stripper foils or extraction foils, both of which are integral to the operation of ion beam accelerators.

“Our new graphene foils are a perfect example of how Applied Nanotech is leveraging research supporting U.S. government priorities into new business opportunities,” said Dr. Scott Rickert, CEO of PEN Inc. Dr. Richard Fink, President of Applied Nanotech noted: “Our team has over 15 years of experience and know-how in the field, including our US Patent No. 6,819,034 that describes the application of graphene in the form of carbon flakes.”

Read more