Technical / Research

Graphene used to grow the world's smallest microLEDs and highest-density microLED arrays

Researchers from MIT, in collaboration with researchers from other Universities in the US and Korea, have used graphene (and hBN) to develop full-color vertically-stacked microLEDs  - that achieve the highest array density (5100 PPI) and the smallest size (4 µm) reported to date.

The researchers developed a 2D-materials based layer transfer (2DLT) technique - that involves growing the LEDs on 2D material-coated substrates, removing the LEDs, and then sttacking them. For the red LEDs, the researchers used graphene, coated on a GaAs wafer, while for the green and blue LEDs, they used hBN on sapphire wafers. The graphene red LEDs were transferred using remote epitaxy, while the hBN blue and green ones were removed using Van der Waals epitaxy.

Read the full story Posted: Feb 02,2023

Researchers find superconductivity that can be turned on and off in "magic angle" graphene

Researchers at MIT and National Institute for Materials Science in Tsukuba, Japan, have found a new and intriguing property of “magic-angle” graphene: superconductivity that can be turned on and off with an electric pulse, much like a light switch.

The discovery could lead to ultrafast, energy-efficient superconducting transistors for neuromorphic devices — electronics designed to operate in a way similar to the rapid on/off firing of neurons in the human brain.

Read the full story Posted: Jan 29,2023

Researchers develop improved method for producing graphene-based gas sensors

Researchers from Penn State and University of Electronic Science and Technology of China recently enhanced their gas sensor manufacturing process through an in situ laser-assisted manufacturing approach, improving on their previous method of drop casting (dropping materials one by one onto a substrate using a pipette. 

Flexible gas sensors can be used as medical devices to identify health conditions by detecting oxygen or carbon dioxide levels in the breath or sweat. They are also useful for monitoring air quality in indoor or outdoor environments by detecting gas, biomolecules and chemicals. 

Read the full story Posted: Jan 27,2023

Researchers deepen understanding of graphene growth on liquid metal catalysts

Liquid metal catalysts have recently been attracting attention for synthesizing high-quality 2D materials facilitated via the catalysts’ perfectly smooth surface. However, the microscopic catalytic processes occurring at the surface are still largely unclear because liquid metals escape the accessibility of traditional experimental and computational surface science approaches. 

An EU-funded collaboration of researchers that included teams from Fritz Haber Institute of the Max Planck Society, The European Synchrotron- ESRF, Technical University of Munich (TUM), Aarhus University,  Leiden University and Université Grenoble Alpes used novel in situ and in silico techniques to achieve an atomic-level characterization of the graphene adsorption height above liquid Cu, reaching quantitative agreement within 0.1 Å between experiment and theory.

Read the full story Posted: Jan 24,2023

Researchers develop graphene-based olfactory sensors to detect odor molecules

Researchers at Tokyo Institute of Technology (Tokyo Tech) and Toshiba Corporation recently demonstrated how graphene-based olfactory sensors could detect odor molecules depending on the design of peptide sequences. They showed that graphene field-effect transistors (GFETs) functionalized with designable peptides could be utilized to develop electronic devices that imitate olfactory receptors and then emulate the sense of smell by selectively detecting odor molecules.

Olfactory sensing is an integral part of many industries like food, cosmetics, healthcare, and environmental monitoring. Currently, most commonly utilized methods for detecting and evaluating odor molecules is called gas chromatography–mass spectrometry (GC–MS). While GC–MS is effective, it has certain limitations like confined sensitivity and heavy setup. As a result, researchers are in the search of user-friendly and highly sensitive alternatives.

Read the full story Posted: Jan 21,2023

Graphene helps NIST team to improve its flagship device for measuring mass

The National Institute of Standards and Technology (NIST) houses a room-sized electromechanical machine called the NIST-4 Kibble balance. The instrument can already measure the mass of objects of roughly 1 kilogram as accurately as any device in the world. But now, NIST researchers have used graphene to further improved their Kibble balance’s performance by adding to it a custom-built device that provides an exact definition of electrical resistance.

The device is called the quantum Hall array resistance standard (QHARS), and it consists of a set of several smaller devices that use a quirk of quantum physics to generate extremely precise amounts of electrical resistance. The improvement should help scientists use their balances to measure masses smaller than 1 kilogram with high accuracy, something no other Kibble balance has done before.

Read the full story Posted: Jan 19,2023

Graphene-silicon dioxide composite enables optical tractor beam that can pull macroscopic objects via laser light

Researchers from QingDao University of Science and Technology have created a proof-of-concept optical tractor beam that can pull macroscopic objects via laser light. 

In the study, the research team essentially amplified the force with which light can pull objects. They accomplished this by developing a composite structure made of graphene-silicon dioxide that, when irradiated with a laser, creates a reverse temperature difference—in other words, the side facing away from the laser warms up. This causes the gas molecules on their back side to receive more energy, pushing the object toward the laser’s source. When conducted in a rarified gas environment, the force was strong enough to move macroscopic objects.

Read the full story Posted: Jan 15,2023

All-Canadian Project Arrow concept unveiled at CES, with graphene battery tech by VoltaXplore

Project Arrow, a collaboration between nearly 60 different companies in Canada that is led by the Automotive Parts Manufacturers’ Association (APMA), aims to develop an all-Canadian electric SUV. A few days ago, at the CES (Consumer Electronics Show) event in Las Vegas, a fully operational prototype was unveiled.

Reports suggest that the Canadian government contributed CAD$5 million (over USD$3.7 million) toward the electric compact SUV’s development. Ontario pledged CAD$1.8 million (over USD$1.3 million) and Quebec said it would allocate CAD$1.4 million (over USD$1 million) over 18 months to small- and medium-sized businesses that make connected or autonomous zero-emission automotive components and systems, including those looking to get involved with Project Arrow.

Read the full story Posted: Jan 08,2023

New material made from a covalent network of fullerenes dubbed "grapehene's cousin"

A team of researchers from Columbia University, University of Virginia, University of Rhode Island, Amherst College, Barnard College and Harvard University have discovered a new type of carbon material: graphullerene.

The material is a new 2D form of carbon made up of layers of linked fullerenes peeled into ultrathin thin flakes from a larger graphullerite crystal—similarly to the way graphene is peeled from crystals of graphite.

Read the full story Posted: Jan 07,2023

Researchers take a step towards graphene electronics

Researchers from Georgia Institute of Technology, National High Magnetic Field Laboratory, Tianjin University, CNRS and Kwansei Gakuin University have developed a new graphene-based nanoelectronics platform compatible with conventional microelectronics manufacturing, potentially paving the way for a successor to silicon.
    
Walter de Heer, Regents' Professor in the School of Physics at the Georgia Institute of Technology, and his collaborators, have developed a new nanoelectronics platform based on graphene. The technology is compatible with conventional microelectronics manufacturing, a necessity for any viable alternative to silicon. In the course of their research, the team may have also discovered a new quasiparticle. Their discovery could lead to manufacturing smaller, faster, more efficient, and more sustainable computer chips, and has potential implications for quantum and high-performance computing.

Read the full story Posted: Dec 22,2022