Category Archives: graphene

Graphene-based nanoelectronics platform, a replacement for silicon?

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A December 31, 2022 news item on phys.org describes research into replacing silicon in the field of electronics, Note: Links have been removed,

A pressing quest in the field of nanoelectronics is the search for a material that could replace silicon. Graphene has seemed promising for decades. But its potential has faltered along the way, due to damaging processing methods and the lack of a new electronics paradigm to embrace it. With silicon nearly maxed out in its ability to accommodate faster computing, the next big nanoelectronics platform is needed now more than ever.

Walter de Heer, Regents’ Professor in the School of Physics at the Georgia Institute of Technology [Georgia Tech], has taken a critical step forward in making the case for a successor to silicon. De Heer and his collaborators have developed a new nanoelectronics platform based on graphene—a single sheet of carbon atoms. The technology is compatible with conventional microelectronics manufacturing, a necessity for any viable alternative to silicon.

In the course of their research, published in Nature Communications, 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.

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A January 3, 2023 Georgia Institute of Technology news release (also on EurekAlert but published December 21, 2022] by Catherine Barzler, which originated the news item, delves further into the work

“Graphene’s power lies in its flat, two-dimensional structure that is held together by the strongest chemical bonds known,” de Heer said. “It was clear from the beginning that graphene can be miniaturized to a far greater extent than silicon — enabling much smaller devices, while operating at higher speeds and producing much less heat. This means that, in principle, more devices can be packed on a single chip of graphene than with silicon.”

In 2001, de Heer proposed an alternative form of electronics based on epitaxial graphene, or epigraphene — a layer of graphene that was found to spontaneously form on top of silicon carbide crystal, a semiconductor used in high power electronics. At the time, researchers found that electric currents flow without resistance along epigraphene’s edges, and that graphene devices could be seamlessly interconnected without metal wires. This combination allows for a form of electronics that relies on the unique light-like properties of graphene electrons.

“Quantum interference has been observed in carbon nanotubes at low temperatures, and we expect to see similar effects in epigraphene ribbons and networks,” de Heer said. “This important feature of graphene is not possible with silicon.”

Building the Platform

To create the new nanoelectronics platform, the researchers created a modified form of epigraphene on a silicon carbide crystal substrate. In collaboration with researchers at the Tianjin International Center for Nanoparticles and Nanosystems at the University of Tianjin, China, they produced unique silicon carbide chips from electronics-grade silicon carbide crystals. The graphene itself was grown at de Heer’s laboratory at Georgia Tech using patented furnaces.

The researchers used electron beam lithography, a method commonly used in microelectronics, to carve the graphene nanostructures and weld their edges to the silicon carbide chips. This process mechanically stabilizes and seals the graphene’s edges, which would otherwise react with oxygen and other gases that might interfere with the motion of the charges along the edge.

Finally, to measure the electronic properties of their graphene platform, the team used a cryogenic apparatus that allows them to record its properties from a near-zero temperature to room temperature.

Observing the Edge State

The electric charges the team observed in the graphene edge state were similar to photons in an optical fiber that can travel over large distances without scattering. They found that the charges traveled for tens of thousands of nanometers along the edge before scattering. Graphene electrons in previous technologies could only travel about 10 nanometers before bumping into small imperfections and scattering in different directions.

“What’s special about the electric charges in the edges is that they stay on the edge and keep on going at the same speed, even if the edges are not perfectly straight,” said Claire Berger, physics professor at Georgia Tech and director of research at the French National Center for Scientific Research in Grenoble, France.

In metals, electric currents are carried by negatively charged electrons. But contrary to the researchers’ expectations, their measurements suggested that the edge currents were not carried by electrons or by holes (a term for positive quasiparticles indicating the absence of an electron). Rather, the currents were carried by a highly unusual quasiparticle that has no charge and no energy, and yet moves without resistance. The components of the hybrid quasiparticle were observed to travel on opposite sides of the graphene’s edges, despite being a single object.

The unique properties indicate that the quasiparticle might be one that physicists have been hoping to exploit for decades — the elusive Majorana fermion predicted by Italian theoretical physicist Ettore Majorana in 1937.

“Developing electronics using this new quasiparticle in seamlessly interconnected graphene networks is game changing,” de Heer said.

It will likely be another five to 10 years before we have the first graphene-based electronics, according to de Heer. But thanks to the team’s new epitaxial graphene platform, technology is closer than ever to crowning graphene as a successor to silicon.

Here’s a link to and a citation for the paper,

An epitaxial graphene platform for zero-energy edge state nanoelectronics by Vladimir S. Prudkovskiy, Yiran Hu, Kaimin Zhang, Yue Hu, Peixuan Ji, Grant Nunn, Jian Zhao, Chenqian Shi, Antonio Tejeda, David Wander, Alessandro De Cecco, Clemens B. Winkelmann, Yuxuan Jiang, Tianhao Zhao, Katsunori Wakabayashi, Zhigang Jiang, Lei Ma, Claire Berger & Walt A. de Heer. Nature Communications volume 13, Article number: 7814 (2022) DOI: https://doi.org/10.1038/s41467-022-34369-4 Published 19 December 2022

This paper is open access.

Graphene goes to the moon

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The people behind the European Union’s Graphene Flagship programme (if you need a brief explanation, keep scrolling down to the “What is the Graphene Flagship?” subhead) and the United Arab Emirates have got to be very excited about the announcement made in a November 29, 2022 news item on Nanowerk, Note: Canadians too have reason to be excited as of April 3, 2023 when it was announced that Canadian astronaut Jeremy Hansen was selected to be part of the team on NASA’s [US National Aeronautics and Space Administration] Artemis II to orbit the moon (April 3, 2023 CBC news online article by Nicole Mortillaro) ·

Graphene Flagship Partners University of Cambridge (UK) and Université Libre de Bruxelles (ULB, Belgium) paired up with the Mohammed bin Rashid Space Centre (MBRSC, United Arab Emirates), and the European Space Agency (ESA) to test graphene on the Moon. This joint effort sees the involvement of many international partners, such as Airbus Defense and Space, Khalifa University, Massachusetts Institute of Technology, Technische Universität Dortmund, University of Oslo, and Tohoku University.

The Rashid rover is planned to be launched on 30 November 2022 [Note: the launch appears to have occurred on December 11, 2022; keep scrolling for more about that] from Cape Canaveral in Florida and will land on a geologically rich and, as yet, only remotely explored area on the Moon’s nearside – the side that always faces the Earth. During one lunar day, equivalent to approximately 14 days on Earth, Rashid will move on the lunar surface investigating interesting geological features.

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A November 29, 2022 Graphene Flagship press release (also on EurekAlert), which originated the news item, provides more details,

The Rashid rover wheels will be used for repeated exposure of different materials to the lunar surface. As part of this Material Adhesion and abrasion Detection experiment, graphene-based composites on the rover wheels will be used to understand if they can protect spacecraft against the harsh conditions on the Moon, and especially against regolith (also known as ‘lunar dust’).

Regolith is made of extremely sharp, tiny and sticky grains and, since the Apollo missions, it has been one of the biggest challenges lunar missions have had to overcome. Regolith is responsible for mechanical and electrostatic damage to equipment, and is therefore also hazardous for astronauts. It clogs spacesuits’ joints, obscures visors, erodes spacesuits and protective layers, and is a potential health hazard.  

University of Cambridge researchers from the Cambridge Graphene Centre produced graphene/polyether ether ketone (PEEK) composites. The interaction of these composites with the Moon regolith (soil) will be investigated. The samples will be monitored via an optical camera, which will record footage throughout the mission. ULB researchers will gather information during the mission and suggest adjustments to the path and orientation of the rover. Images obtained will be used to study the effects of the Moon environment and the regolith abrasive stresses on the samples.

This moon mission comes soon after the ESA announcement of the 2022 class of astronauts, including the Graphene Flagship’s own Meganne Christian, a researcher at Graphene Flagship Partner the Institute of Microelectronics and Microsystems (IMM) at the National Research Council of Italy.

“Being able to follow the Moon rover’s progress in real time will enable us to track how the lunar environment impacts various types of graphene-polymer composites, thereby allowing us to infer which of them is most resilient under such conditions. This will enhance our understanding of how graphene-based composites could be used in the construction of future lunar surface vessels,” says Sara Almaeeni, MBRSC science team lead, who designed Rashid’s communication system.

“New materials such as graphene have the potential to be game changers in space exploration. In combination with the resources available on the Moon, advanced materials will enable radiation protection, electronics shielding and mechanical resistance to the harshness of the Moon’s environment. The Rashid rover will be the first opportunity to gather data on the behavior of graphene composites within a lunar environment,” says Carlo Iorio, Graphene Flagship Space Champion, from ULB.

Leading up to the Moon mission, a variety of inks containing graphene and related materials, such as conducting graphene, insulating hexagonal boron nitride and graphene oxide, semiconducting molybdenum disulfide, prepared by the University of Cambridge and ULB were also tested on the MAterials Science Experiment Rocket 15 (MASER 15) mission, successfully launched on the 23rd of November 2022 from the Esrange Space Center in Sweden. This experiment, named ARLES-2 (Advanced Research on Liquid Evaporation in Space) and supported by European and UK space agencies (ESA, UKSA) included contributions from Graphene Flagship Partners University of Cambridge (UK), University of Pisa (Italy) and Trinity College Dublin (Ireland), with many international collaborators, including Aix-Marseille University (France), Technische Universität Darmstadt (Germany), York University (Canada), Université de Liège (Belgium), University of Edinburgh and Loughborough.

This experiment will provide new information about the printing of GMR inks in weightless conditions, contributing to the development of new addictive manufacturing procedures in space such as 3d printing. Such procedures are key for space exploration, during which replacement components are often needed, and could be manufactured from functional inks.

“Our experiments on graphene and related materials deposition in microgravity pave the way addictive manufacturing in space. The study of the interaction of Moon regolith with graphene composites will address some key challenges brought about by the harsh lunar environment,” says Yarjan Abdul Samad, from the Universities of Cambridge and Khalifa, who prepared the samples and coordinated the interactions with the United Arab Emirates.    

“The Graphene Flagship is spearheading the investigation of graphene and related materials (GRMs) for space applications. In November 2022, we had the first member of the Graphene Flagship appointed to the ESA astronaut class. We saw the launch of a sounding rocket to test printing of a variety of GRMs in zero gravity conditions, and the launch of a lunar rover that will test the interaction of graphene—based composites with the Moon surface. Composites, coatings and foams based on GRMs have been at the core of the Graphene Flagship investigations since its beginning. It is thus quite telling that, leading up to the Flagship’s 10th anniversary, these innovative materials are now to be tested on the lunar surface. This is timely, given the ongoing effort to bring astronauts back to the Moon, with the aim of building lunar settlements. When combined with polymers, GRMs can tailor the mechanical, thermal, electrical properties of then host matrices. These pioneering experiments could pave the way for widespread adoption of GRM-enhanced materials for space exploration,” says Andrea Ferrari, Science and Technology Officer and Chair of the Management Panel of the Graphene Flagship. 

Caption: The MASER15 launch Credit: John-Charles Dupin

A pioneering graphene work and a first for the Arab World

A December 11, 2022 news item on Alarabiya news (and on CNN) describes the ‘graphene’ launch which was also marked the Arab World’s first mission to the moon,

The United Arab Emirates’ Rashid Rover – the Arab world’s first mission to the Moon – was launched on Sunday [December 11, 2022], the Mohammed bin Rashid Space Center (MBRSC) announced on its official Twitter account.

The launch came after it was previously postponed for “pre-flight checkouts.”

The launch of a SpaceX Falcon 9 rocket carrying the UAE’s Rashid rover successfully took off from Cape Canaveral, Florida.

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The Rashid rover – built by Emirati engineers from the UAE’s Mohammed bin Rashid Space Center (MBRSC) – is to be sent to regions of the Moon unexplored by humans.

What is the Graphene Flagship?

In 2013, the Graphene Flagship was chosen as one of two FET (Future and Emerging Technologies) funding projects (the other being the Human Brain Project) each receiving €1 billion to be paid out over 10 years. In effect, it’s a science funding programme specifically focused on research, development, and commercialization of graphene (a two-dimensional [it has length and width but no depth] material made of carbon atoms).

You can find out more about the flagship and about graphene here.

Turning asphaltene into graphene

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Asphaltene (or asphaltenes are) is waste material that can be turned into graphene according to scientists at Rice University (Texas, US), from a November 18, 2022 news item on ScienceDaily,

Asphaltenes, a byproduct of crude oil production, are a waste material with potential. Rice University scientists are determined to find it by converting the carbon-rich resource into useful graphene.

Muhammad Rahman, an assistant research professor of materials science and nanoengineering, is employing Rice’s unique flash Joule heating process to convert asphaltenes instantly into turbostratic (loosely aligned) graphene and mix it into composites for thermal, anti-corrosion and 3D-printing applications.

The process makes good use of material otherwise burned for reuse as fuel or discarded into tailing ponds and landfills. Using at least some of the world’s reserve of more than 1 trillion barrels of asphaltene as a feedstock for graphene would be good for the environment as well.

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A November 17, 2022 Rice University news release (also on EurekAlert), which originated the news item, expands on this exciting news, Note: Links have been removed,

“Asphaltene is a big headache for the oil industry, and I think there will be a lot of interest in this,” said Rahman, who characterized the process as both a scalable and sustainable way to reduce carbon emissions from burning asphaltene.

Rahman is a lead corresponding author of the paper in Science Advances co-led by Rice chemist James Tour, whose lab developed flash Joule heating, materials scientist Pulickel Ajayan and Md Golam Kibria, an assistant professor of chemical and petroleum engineering at the University of Calgary, Canada.

Asphaltenes are 70% to 80% carbon already. The Rice lab combines it with about 20% of carbon black to add conductivity and flashes it with a jolt of electricity, turning it into graphene in less than a second. Other elements in the feedstock, including hydrogen, nitrogen, oxygen and sulfur, are vented away as gases.

“We try to keep the carbon black content as low as possible because we want to maximize the utilization of asphaltene,” Rahman said.

“The government has been putting pressure on the petroleum industries to take care of this,” said Rice graduate student and co-lead author M.A.S.R. Saadi. “There are billions of barrels of asphaltene available, so we began working on this project primarily to see if we could make carbon fiber. That led us to think maybe we should try making graphene with flash Joule heating.”

Assured that Tour’s process worked as well on asphaltene as it did on various other feedstocks, including plastic, electronic waste, tires, coal fly ash and even car parts, the researchers set about making things with their graphene. 

Saadi, who works with Rahman and Ajayan, mixed the graphene into composites, and then into polymer inks bound for 3D printers. “We’ve optimized the ink rheology to show that it is printable,” he said, noting the inks have no more than 10% of graphene mixed in. Mechanical testing of printed objects is forthcoming, he said.

Rice graduate student Paul Advincula, a member of the Tour lab, is co-lead author of the paper. Co-authors are Rice graduate students Md Shajedul Hoque Thakur, Ali Khater, Jacob Beckham and Minghe Lou, undergraduate Aasha Zinke and postdoctoral researcher Soumyabrata Roy; research fellow Shabab Saad, alumnus Ali Shayesteh Zeraati, graduate student Shariful Kibria Nabil and postdoctoral associate Md Abdullah Al Bari of the University of Calgary; graduate student Sravani Bheemasetti and Venkataramana Gadhamshetty, an associate professor, at the South Dakota School of Mines and Technology and its 2D Materials of Biofilm Engineering Science and Technology Center; and research assistant Yiwen Zheng and Aniruddh Vashisth, an assistant professor of mechanical engineering, of the University of Washington.

The research was funded by the Alberta Innovates for Carbon Fiber Grand Challenge programs, the Air Force Office of Scientific Research (FA9550-19-1-0296), the U.S. Army Corps of Engineers (W912HZ-21-2-0050) and the National Science Foundation (1849206, 1920954).  

Here’s a link to and a citation for the paper,

Sustainable valorization of asphaltenes via flash joule heating by M.A.S.R. Saadi, Paul A. Advincula, Md Shajedul Hoque Thakur, Ali Zein Khater, Shabab Saad, Ali Shayesteh Zeraati, Shariful Kibria Nabil, Aasha Zinke, Soumyabrata Roy, Minghe Lou, Sravani N. Bheemasetti, Md Abdullah Al Bari, Yiwen Zheng, Jacob L. Beckham, Venkataramana Gadhamshetty, Aniruddh Vashisth, Md Golam Kibria, James M. Tour, Pulickel M. Ajayan, and Muhammad M. Rahman. Science Advances 18 Nov 2022 Vol 8, Issue 46 DOI: 10.1126/sciadv.add3555

This paper is open access.

Graphene can be used in quantum components

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A November 3, 2022 news item on phys.org provides a brief history of graphene before announcing the latest work from ETH Zurich,

Less than 20 years ago, Konstantin Novoselov and Andre Geim first created two-dimensional crystals consisting of just one layer of carbon atoms. Known as graphene, this material has had quite a career since then.

Due to its exceptional strength, graphene is used today to reinforce products such as tennis rackets, car tires or aircraft wings. But it is also an interesting subject for fundamental research, as physicists keep discovering new, astonishing phenomena that have not been observed in other materials.

The right twist

Bilayer graphene crystals, in which the two atomic layers are slightly rotated relative to each other, are particularly interesting for researchers. About one year ago, a team of researchers led by Klaus Ensslin and Thomas Ihn at ETH Zurich’s Laboratory for Solid State Physics was able to demonstrate that twisted graphene could be used to create Josephson junctions, the fundamental building blocks of superconducting devices.

Based on this work, researchers were now able to produce the first superconducting quantum interference device, or SQUID, from twisted graphene for the purpose of demonstrating the interference of superconducting quasiparticles. Conventional SQUIDs are already being used, for instance in medicine, geology and archaeology. Their sensitive sensors are capable of measuring even the smallest changes in magnetic fields. However, SQUIDs work only in conjunction with superconducting materials, so they require cooling with liquid helium or nitrogen when in operation.

In quantum technology, SQUIDs can host quantum bits (qubits); that is, as elements for carrying out quantum operations. “SQUIDs are to superconductivity what transistors are to semiconductor technology—the fundamental building blocks for more complex circuits,” Ensslin explains.

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A November 3, 2022 ETH Zurich news release by Felix Würsten, which originated the news item, delves further into the work,

The spectrum is widening

The graphene SQUIDs created by doctoral student Elías Portolés are not more sensitive than their conventional counterparts made from aluminium and also have to be cooled down to temperatures lower than 2 degrees above absolute zero. “So it’s not a breakthrough for SQUID technology as such,” Ensslin says. However, it does broaden graphene’s application spectrum significantly. “Five years ago, we were already able to show that graphene could be used to build single-electron transistors. Now we’ve added superconductivity,” Ensslin says.

What is remarkable is that the graphene’s behaviour can be controlled in a targeted manner by biasing an electrode. Depending on the voltage applied, the material can be insulating, conducting or superconducting. “The rich spectrum of opportunities offered by solid-state physics is at our disposal,” Ensslin says.

Also interesting is that the two fundamental building blocks of a semiconductor (transistor) and a superconductor (SQUID) can now be combined in a single material. This makes it possible to build novel control operations. “Normally, the transistor is made from silicon and the SQUID from aluminium,” Ensslin says. “These are different materials requiring different processing technologies.”

An extremely challenging production process

Superconductivity in graphene was discovered by an MIT [Massachusetts Institute of Technology] research group five years ago, yet there are only a dozen or so experimental groups worldwide that look at this phenomenon. Even fewer are capable of converting superconducting graphene into a functioning component.

The challenge is that scientists have to carry out several delicate work steps one after the other: First, they have to align the graphene sheets at the exact right angle relative to each other. The next steps then include connecting electrodes and etching holes. If the graphene were to be heated up, as happens often during cleanroom processing, the two layers re-align the twist angle vanishes. “The entire standard semiconductor technology has to be readjusted, making this an extremely challenging job,” Portolés says.

The vision of hybrid systems

Ensslin is thinking one step ahead. Quite a variety of different qubit technologies are currently being assessed, each with its own advantages and disadvantages. For the most part, this is being done by various research groups within the National Center of Competence in Quantum Science and Technology (QSIT). If scientists succeed in coupling two of these systems using graphene, it might be possible to combine their benefits as well. “The result would be two different quantum systems on the same crystal,” Ensslin says.

This would also generate new possibilities for research on superconductivity. “With these components, we might be better able to understand how superconductivity in graphene comes about in the first place,” he adds. “All we know today is that there are different phases of superconductivity in this material, but we do not yet have a theoretical model to explain them.”

Here’s a link to and a citation for the paper,

A tunable monolithic SQUID in twisted bilayer graphene by Elías Portolés, Shuichi Iwakiri, Giulia Zheng, Peter Rickhaus, Takashi Taniguchi, Kenji Watanabe, Thomas Ihn, Klaus Ensslin & Folkert K. de Vries. Nature Nanotechnology volume 17, pages 1159–1164 (2022) Issue Date: November 2022 DOI: https://doi.org/10.1038/s41565-022-01222-0 Published online: 24 October 2022

This paper is behind a paywall.

Neuromorphic (brainlike) computing and your car (a Mercedes Benz Vision AVTR concept car)

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If you’ve ever fantasized about a batmobile of your own, the dream could come true soon,

Mercedes Berz VISION AVTR [downloaded from https://www.mercedes-benz.com/en/innovation/concept-cars/vision-avtr/]

It was the mention of neuromorphic computing in a television ad sometime in September 2022 that sent me on a mission to find out what Mercedes Benz means when they use neuromorphic computing to describe a feature found in their Vision AVTR concept car. First, a little bit about the car (from the Vision AVTR webpage accessed in October 2022),

VISION AVTR – inspired by AVATAR.

The name of the groundbreaking concept vehicle stands not only for the close collaboration in developing the show car together with the AVATAR team but also for ADVANCED VEHICLE TRANSFORMATION. This concept vehicle embodies the vision of Mercedes-Benz designers, engineers and trend researchers for mobility in the distant future.

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Organic battery technology.

The VISION AVTR was designed in line with its innovative electric drive. This is based on a particularly powerful and compact high-voltage battery. For the first time, the revolutionary battery technology is based on graphene-based [emphasis mine] organic cell chemistry and thus completely eliminates rare, toxic and expensive earths such as metals. Electromobility thus becomes independent of fossil resources. An absolute revolution is also the recyclability by composting, which is 100% recyclable due to the materiality. As a result, Mercedes-Benz underlines the high relevance of a future circular economy in the raw materials sector.

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Masterpiece of efficiency.

At Mercedes-Benz, the consideration of efficiency goes far beyond the drive concept, because with increasing digitalisation, the performance of the large number of so-called secondary consumers also comes into focus – along with their efficient energy supply, without negatively affecting the drive power of the vehicle itself. Energy consumption per computing operation is already a key target in the development of new computer chips. This trend will continue in the coming years with the growth of sensors and artificial intelligence in the automotive industry. The neuro-inspired approach of the VISION AVTR, including so-called neuromorphic hardware, promises to minimise the energy requirements of sensors, chips and other components to a few watts. [emphasis mine] Their energy supply is provided by the cached current of the integrated solar plates on the back of the VISION AVTR. The 33 multi-directionally movable surface elements act as “bionic flaps”.

Interior and exterior merge.

For the first time, Mercedes-Benz has worked with a completely new design approach in the design of the VISION AVTR. The holistic concept combines the design disciplines interior, exterior and UX [user experience] from the first sketch. Man and human perception are the starting point of a design process from the inside out. The design process begins with the experience of the passengers and consciously focuses on the perception and needs of the passengers. The goal was to create a car that prolongs the perception of its passengers. It was also a matter of creating an immersive experience space in which passengers connect with each other, with the vehicle and the surrounding area [emphasis mine ] in a unique way.

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Intuitive control.

The VISION AVTR already responds to the approach of the passengers by visualising the energy and information flow of the environment with digital neurons that flow through the grille through the wheels to the rear area. The first interaction in the interior between man and vehicle happens completely intuitively via the control unit: by placing the hand on the centre console, the interior comes to life and the vehicle recognises the driver by his breathing. This is made visible on the instrument panel and on the user’s hand. The VISION AVTR thus establishes a biometric connection with the driver [emphasis mine] and increases his awareness of the environment. The digital neurons flow from the interior into the exterior and visualise the flow of energy and information. For example, when driving, the neurons flow over the outside of the vehicle. [emphasis mine] When changing direction, the energy flows to the corresponding side of the vehicle.

The vehicle as an immersive experience space.

The visual connection between passengers and the outside world is created by the curved display module, which replaces a conventional dashboard. The outside world around the vehicle and the surrounding area is shown in real-time 3D graphics and at the same time shows what is happening on the road in front of the vehicle. Combined with energy lines, these detailed real-time images bring the interior to life and allow passengers to discover and interact with the environment in a natural way with different views of the outside world. Three wonders of nature – the Huangshan Mountains of China, the 115-metre-high Hyperion Tree found in the United States and the pink salt Lake Hillier from Australia – can be explored in detail. Passengers become aware of various forces of nature that are not normally visible to the human eye, such as magnetic fields, bioenergy or ultraviolet light.

The curved display module in the Mercedes-Benz VISION AVTR – inspired by AVATAR
[downloaded from https://www.mercedes-benz.com/en/innovation/concept-cars/vision-avtr/]

Bionic formal language.

When the boundaries between vehicle and living beings are lifted, Mercedes-Benz combines luxury and sustainability and works to make the vehicles as resource-saving as possible. With the VISION AVTR, the brand is now showing how a vehicle can blend harmoniously into its environment and communicate with it. In the ecosystem of the future, the ultimate luxury is the fusion of human and nature with the help of technology. The VISION AVTR is thus an example of sustainable luxury in the field of design. As soon as you get in, the car becomes an extension of your own body and a tool to discover the environment much as in the film humans can use avatars to extend and expand their abilities.

A few thoughts

The movie, Avatar, was released in 2009 and recently rereleased in movie houses in anticipation of the sequel, Avatar: The Way of Water to be released in December 2022 (Avatar [2009 film] Wikipedia entry). The timing, Avatar and AVTR, is interesting, oui?

Moving onto ‘organic’, which means carbon-based in this instance and, specifically, graphene. Commercialization of graphene is likely top-of-mind for the folks (European Commission) who bet 1B Euros in 2013 with European Union money to fund the Graphene Flagship project. This battery from German company Mercedes Benz must be exciting news for the funders and for people who want to lessen dependency on rare earths. Your battery can be composted safely (according to the advertising).

The other piece of good news, is the neuromorphic computing,

“The neuro-inspired approach of the VISION AVTR, including so-called neuromorphic hardware, promises to minimise the energy requirements of sensors, chips and other components to a few watts.”

On the other hand and keeping in mind the image above (a hand with what looks like an embedded object), it seems a little disconcerting to merge with one’s car, “… passengers connect with each other, with the vehicle and the surrounding area …” which becomes even more disconcerting when this appears in the advertising,

… VISION AVTR thus establishes a biometric connection with the driver … The digital neurons flow from the interior into the exterior and visualise the flow of energy and information. For example, when driving, the neurons flow over the outside of the vehicle.

Are these ‘digital neurons’ flowing around the car like a water current? Also, the car is visualizing? Hmm …

I did manage to find a bit more information about neuromorphic computing although it’s for a different Mercedes Benz concept car (there’s no mention of flowing digital neurons) in a January 18, 2022 article by Sally Ward-Foxton for EE Times (Note: A link has been removed),

The Mercedes Vision EQXX concept car, promoted as “the most efficient Mercedes-Benz ever built,” incorporates neuromorphic computing to help reduce power consumption and extend vehicle range. To that end, BrainChip’s Akida neuromorphic chip enables in-cabin keyword spotting as a more power-efficient way than existing AI-based keyword detection systems.

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“Working with California-based artificial intelligence experts BrainChip, Mercedes-Benz engineers developed systems based on BrainChip’s Akida hardware and software,” Mercedes noted in a statement describing the Vision EQXX. “The example in the Vision EQXX is the “Hey Mercedes” hot-word detection. Structured along neuromorphic principles, it is five to ten times more efficient than conventional voice control,” the carmaker claimed.

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That represents validation of BrainChip’s technology by one of its early-access customers. BrainChip’s Akida chip accelerates spiking neural networks (SNNs) and convolutional neural networks (via conversion to SNNs). It is not limited to a particular application, and also run [sic] person detection, voice or face recognition SNNs, for example, that Mercedes could also explore.

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This January 6, 2022 article by Nitin Dahad for embedded.com describes what were then the latest software innovations in the automotive industry and segues into a description of spiking neural networks (Note: A link has been removed),

The electric vehicle (EV) has clearly become a key topic of discussion, with EV range probably the thing most consumers are probably worried about. To address the range concern, two stories emerged this week – one was Mercedes-Benz’ achieving a 1,000 km range with its VISION EQXX prototype, albeit as a concept car, and General Motors announcing during a CES [Consumer Electronics Show] 2022 keynote its new Chevrolet Silverado EV with 400-mile (640 km) range.

In briefings with companies, I often hear them talk about the software-defined car and the extensive use of software simulation (or we could also call it a digital twin). In the case of both the VISION EQXX and the Silverado EV, software plays a key part. I also spoke to BlackBerry about its IVY platform and how it is laying the groundwork for software-defined vehicles.

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Neuromorphic computing for infotainment

This efficiency is not just being applied to enhancing range though. Mercedes-Benz also points out that its infotainment system uses neuromorphic computing to enable the car to take to “take its cue from the way nature thinks”.

Mercedes-Benz VISION EQXXMercedes-Benz VISION EQXX

The hardware runs spiking neural networks, in which data is coded in discrete spikes and energy only consumed when a spike occurs, reducing energy consumption by orders of magnitude. In order to deliver this, the carmaker worked with BrainChip, developing the systems based on its Akida processor. In the VISION EQXX, this technology enables the “Hey Mercedes” hot-word detection five to ten times more efficiently than conventional voice control. Mercedes-Benz said although neuromorphic computing is still in its infancy, systems like these will be available on the market in just a few years. When applied on scale throughout a vehicle, they have the potential to radically reduce the energy needed to run the latest AI technologies.

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For anyone curious about BrainChip, you can find out more here.

It took a little longer than I hoped but I’m glad that I found out a little more about neuromorphic computing and one application in the automotive industry.

Synaptic transistors for brainlike computers based on (more environmentally friendly) graphene

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An August 9, 2022 news item on ScienceDaily describes research investigating materials other than silicon for neuromorphic (brainlike) computing purposes,

Computers that think more like human brains are inching closer to mainstream adoption. But many unanswered questions remain. Among the most pressing, what types of materials can serve as the best building blocks to unlock the potential of this new style of computing.

For most traditional computing devices, silicon remains the gold standard. However, there is a movement to use more flexible, efficient and environmentally friendly materials for these brain-like devices.

In a new paper, researchers from The University of Texas at Austin developed synaptic transistors for brain-like computers using the thin, flexible material graphene. These transistors are similar to synapses in the brain, that connect neurons to each other.

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An August 8, 2022 University of Texas at Austin news release (also on EurekAlert but published August 9, 2022), which originated the news item, provides more detail about the research,

“Computers that think like brains can do so much more than today’s devices,” said Jean Anne Incorvia, an assistant professor in the Cockrell School of Engineering’s Department of Electrical and Computer Engineer and the lead author on the paper published today in Nature Communications. “And by mimicking synapses, we can teach these devices to learn on the fly, without requiring huge training methods that take up so much power.”

The Research: A combination of graphene and nafion, a polymer membrane material, make up the backbone of the synaptic transistor. Together, these materials demonstrate key synaptic-like behaviors — most importantly, the ability for the pathways to strengthen over time as they are used more often, a type of neural muscle memory. In computing, this means that devices will be able to get better at tasks like recognizing and interpreting images over time and do it faster.

Another important finding is that these transistors are biocompatible, which means they can interact with living cells and tissue. That is key for potential applications in medical devices that come into contact with the human body. Most materials used for these early brain-like devices are toxic, so they would not be able to contact living cells in any way.

Why It Matters: With new high-tech concepts like self-driving cars, drones and robots, we are reaching the limits of what silicon chips can efficiently do in terms of data processing and storage. For these next-generation technologies, a new computing paradigm is needed. Neuromorphic devices mimic processing capabilities of the brain, a powerful computer for immersive tasks.

“Biocompatibility, flexibility, and softness of our artificial synapses is essential,” said Dmitry Kireev, a post-doctoral researcher who co-led the project. “In the future, we envision their direct integration with the human brain, paving the way for futuristic brain prosthesis.”

Will It Really Happen: Neuromorphic platforms are starting to become more common. Leading chipmakers such as Intel and Samsung have either produced neuromorphic chips already or are in the process of developing them. However, current chip materials place limitations on what neuromorphic devices can do, so academic researchers are working hard to find the perfect materials for soft brain-like computers.

“It’s still a big open space when it comes to materials; it hasn’t been narrowed down to the next big solution to try,” Incorvia said. “And it might not be narrowed down to just one solution, with different materials making more sense for different applications.”

The Team: The research was led by Incorvia and Deji Akinwande, professor in the Department of Electrical and Computer Engineering. The two have collaborated many times together in the past, and Akinwande is a leading expert in graphene, using it in multiple research breakthroughs, most recently as part of a wearable electronic tattoo for blood pressure monitoring.

The idea for the project was conceived by Samuel Liu, a Ph.D. student and first author on the paper, in a class taught by Akinwande. Kireev then suggested the specific project. Harrison Jin, an undergraduate electrical and computer engineering student, measured the devices and analyzed data.

The team collaborated with T. Patrick Xiao and Christopher Bennett of Sandia National Laboratories, who ran neural network simulations and analyzed the resulting data.

Here’s a link to and a citation for the ‘graphene transistor’ paper,

Metaplastic and energy-efficient biocompatible graphene artificial synaptic transistors for enhanced accuracy neuromorphic computing by Dmitry Kireev, Samuel Liu, Harrison Jin, T. Patrick Xiao, Christopher H. Bennett, Deji Akinwande & Jean Anne C. Incorvia. Nature Communications volume 13, Article number: 4386 (2022) DOI: https://doi.org/10.1038/s41467-022-32078-6 Published: 28 July 2022

This paper is open access.

Artificial graphene with buckyballs

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A July 21, 2022 news item on Nanowerk describes graphene in its ‘natural’ state and explains what ‘artificial’ graphene is although there is no mention of why variants are a hot topic,

Graphene consists of carbon atoms that crosslink in a plane to form a flat honeycomb structure. In addition to surprisingly high mechanical stability, the material has exciting electronic properties: The electrons behave like massless particles, which can be clearly demonstrated in spectrometric experiments.

Measurements reveal a linear dependence of energy on momentum, namely the so-called Dirac cones – two lines that cross without a band gap – i.e. an energy difference between electrons in the conduction band and those in the valence bands.

Variants in graphene architecture

Artificial variants of graphene architecture are a hot topic in materials research right now. Instead of carbon atoms, quantum dots of silicon have been placed, ultracold atoms have been trapped in the honeycomb lattice with strong laser fields, or carbon monoxide molecules have been pushed into place on a copper surface piece by piece with a scanning tunneling microscope, where they could impart the characteristic graphene properties to the electrons of the copper.

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A July 21, 2022 Helmholtz-Zentrum Berlin (HZB) press release (also on EurekAlert), which originated the news item, describes research into whether or not layering buckyballs onto gold would result in artificial graphene,

Artificial graphene with buckyballs?

A recent study suggested that it is infinitely easier to make artificial graphene using C60 molecules called buckyballs [or buckminsterfullerenes or, more generically, fullerenes]. Only a uniform layer of these needs to be vapor-deposited onto gold for the gold electrons to take on the special graphene properties. Measurements of photoemission spectra appeared to show a kind of Dirac cone.

Analysis of band structures at BESSY II

“That would be really quite amazing,” says Dr. Andrei Varykhalov, of HZB, who heads a photoemission and scanning tunneling microscopy group. “Because the C60 molecule is absolutely nonpolar, it was hard for us to imagine how such molecules would exert a strong influence on the electrons in the gold.” So Varykhalov and his team launched a series of measurements to test this hypothesis.

In tricky and detailed analyses, the Berlin team was able to study C60 layers on gold over a much larger energy range and for different measurement parameters. They used angle-resolved ARPES spectroscopy at BESSY II [third-generation synchrotron radiation source], which enables particularly precise measurements, and also analysed electron spin for some measurements.

Normal behavior

“We see a parabolic relationship between momentum and energy in our measured data, so it’s a very normal behavior. These signals come from the electrons deep in the substrate (gold or copper) and not the layer, which could be affected by the buckyballs,” explains Dr. Maxim Krivenkov, lead author of the study. The team was also able to explain the linear measurement curves from the previous study. “These measurement curves merely mimic the Dirac cones; they are an artifact, so to speak, of a deflection of the photoelectrons as they leave the gold and pass through the C60 layer,” Varykhalov explains. Therefore, the buckyball layer on gold cannot be considered an artificial graphene.

Caption: Measurement data from BESSY II before and after deposition of C60 molecules demonstrate the replication of the band structure and the emergence of cone-like band crossings. A scanning electron microscopy of the buckyballs on gold is superimposed in the centre. Credit: HZB

Here’s a link to and a citation for the paper,

On the problem of Dirac cones in fullerenes on gold by M. Krivenkov, D. Marchenko, M. Sajedi, A. Fedorov, O. J. Clark, J. Sánchez-Barriga, E. D. L. Rienks, O. Rader and A. Varykhalov. Nanoscale, 2022,14, 9124-9133 First published: 23 May 2022

This paper is open access.

Could buckyballs and carbon nanotubes come from the dust and gas of dying stars?

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In this picture of the Spirograph Nebula, a dying star about 2,000 light-years from Earth, NASA’s Hubble Space Telescope revealed some remarkable textures weaving through the star’s envelope of dust and gas. UArizona researchers have now found evidence that complex carbon nanotubes could be forged in such environments.. Credit: NASA and The Hubble Heritage Team (STScI/AURA)

It’s always interesting to come across different news releases announcing the same research. In this case I have two news releases, one from the US National Science Foundation (NSF) and one from the University of Arizona. Let’s start with the July 19, 2022 news item on phys.org (originated by the US NSF),

Astronomers at the University of Arizona have developed a theory to explain the presence of the largest molecules known to exist in interstellar gas.

The team simulated the environment of dying stars and observed the formation of buckyballs (carbon atoms linked to three other carbon atoms by covalent bonds) and carbon nanotubes (rolled up sheets of single-layer carbon atoms). The findings indicate that buckyballs and carbon nanotubes can form when silicon carbide dust — known to be proximate to dying stars — releases carbon in reaction to intense heat, shockwaves and high energy particles.

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Here’s the rest of the July 18, 2022 NSF news release, Note: A link has been removed,

“We know from infrared observations that buckyballs populate the interstellar medium,” said Jacob Bernal, who led the research. “The big problem has been explaining how these massive, complex carbon molecules could possibly form in an environment saturated with hydrogen, which is what you typically have around a dying star.”

Rearranging the structure of graphene (a sheet of single-layer carbon atoms) could create buckyballs and nanotubes. Building on that, the team heated silicon carbide samples to temperatures that would mimic the aura of a dying star and observed the formation of nanotubes.

“We were surprised we could make these extraordinary structures,” Bernal said. “Chemically, our nanotubes are very simple, but they are extremely beautiful.”

Buckyballs are the largest molecules currently known to occur in interstellar space. It is now known that buckyballs containing 60 to 70 carbon atoms are common.

“We know the raw material is there, and we know the conditions are very close to what you’d see near the envelope of a dying star,” study co-author Lucy Ziurys said. “Shock waves pass through the envelope, and the temperature and pressure conditions have been shown to exist in space. We also see buckyballs in planetary nebulae — in other words, we see the beginning and the end products you would expect in our experiments.”

A June 16, 2022 University of Arizona news release by Daniel Stolte (also on EurekAlert) takes a context-rich approach to writing up the proposed theory for how buckyballs and carbon nanotubes (CNTs) form (Note: Links have been removed),

In the mid-1980s, the discovery of complex carbon molecules drifting through the interstellar medium garnered significant attention, with possibly the most famous examples being Buckminsterfullerene, or “buckyballs” – spheres consisting of 60 or 70 carbon atoms. However, scientists have struggled to understand how these molecules can form in space.

In a paper accepted for publication in the Journal of Physical Chemistry A, researchers from the University of Arizona suggest a surprisingly simple explanation. After exposing silicon carbide – a common ingredient of dust grains in planetary nebulae – to conditions similar to those found around dying stars, the researchers observed the spontaneous formation of carbon nanotubes, which are highly structured rod-like molecules consisting of multiple layers of carbon sheets. The findings were presented on June 16 [2022] at the 240th Meeting of the American Astronomical Society in Pasadena, California.

Led by UArizona researcher Jacob Bernal, the work builds on research published in 2019, when the group showed that they could create buckyballs using the same experimental setup. The work suggests that buckyballs and carbon nanotubes could form when the silicon carbide dust made by dying stars is hit by high temperatures, shock waves and high-energy particles, leaching silicon from the surface and leaving carbon behind.

The findings support the idea that dying stars may seed the interstellar medium with nanotubes and possibly other complex carbon molecules. The results have implications for astrobiology, as they provide a mechanism for concentrating carbon that could then be transported to planetary systems.

“We know from infrared observations that buckyballs populate the interstellar medium,” said Bernal, a postdoctoral research associate in the UArizona Lunar and Planetary Laboratory. “The big problem has been explaining how these massive, complex carbon molecules could possibly form in an environment saturated with hydrogen, which is what you typically have around a dying star.”

The formation of carbon-rich molecules, let alone species containing purely carbon, in the presence of hydrogen is virtually impossible due to thermodynamic laws. The new study findings offer an alternative scenario: Instead of assembling individual carbon atoms, buckyballs and nanotubes could result from simply rearranging the structure of graphene – single-layered carbon sheets that are known to form on the surface of heated silicon carbide grains.

This is exactly what Bernal and his co-authors observed when they heated commercially available silicon carbide samples to temperatures occurring in dying or dead stars and imaged them. As the temperature approached 1,050 degreesCelsius, small hemispherical structures with the approximate size of about 1 nanometer were observed at the grain surface. Within minutes of continued heating, the spherical buds began to grow into rod-like structures, containing several graphene layers with curvature and dimensions indicating a tubular form. The resulting nanotubules ranged from about 3 to 4 nanometers in length and width, larger than buckyballs. The largest imaged specimens were comprised of more than four layers of graphitic carbon. During the heating experiment, the tubes were observed to wiggle before budding off the surface and getting sucked into the vacuum surrounding the sample.

“We were surprised we could make these extraordinary structures,” Bernal said. “Chemically, our nanotubes are very simple, but they are extremely beautiful.”

Named after their resemblance to architectural works by Richard Buckminster Fuller, fullerenes are the largest molecules currently known to occur in interstellar space, which for decades was believed to be devoid of any molecules containing more than a few atoms, 10 at most. It is now well established that the fullerenes C60 and C70, which contain 60 or 70 carbon atoms, respectively, are common ingredients of the interstellar medium.

One of the first of its kind in the world, the transmission electron microscope housed at the Kuiper Materials Imaging and Characterization Facility at UArizona is uniquely suited to simulate the planetary nebula environment. Its 200,000-volt electron beam can probe matter down to 78 picometers – the distance of two hydrogen atoms in a water molecule – making it possible to see individual atoms. The instrument operates in a vacuum closely resembling the pressure – or lack thereof – thought to exist in circumstellar environments.

While a spherical C60 molecule measures 0.7 nanometers in diameter, the nanotube structures formed in this experiment measured several times the size of C60, easily exceeding 1,000 carbon atoms. The study authors are confident their experiments accurately replicated the temperature and density conditions that would be expected in a planetary nebula, said co-author Lucy Ziurys, a UArizona Regents Professor of Astronomy, Chemistry and Biochemistry.

“We know the raw material is there, and we know the conditions are very close to what you’d see near the envelope of a dying star,” she said. “There are shock waves that pass through the envelope, so the temperature and pressure conditions have been shown to exist in space. We also see buckyballs in these planetary nebulae – in other words, we see the beginning and the end products you would expect in our experiments.”

These experimental simulations suggest that carbon nanotubes, along with the smaller fullerenes, are subsequently injected into the interstellar medium. Carbon nanotubes are known to have high stability against radiation, and fullerenes are able to survive for millions of years when adequately shielded from high-energy cosmic radiation. Carbon-rich meteorites, such as carbonaceous chondrites, could contain these structures as well, the researchers propose.

According to study co-author Tom Zega, a professor in the UArizona Lunar and Planetary Lab, the challenge is finding nanotubes in these meteorites, because of the very small grain sizes and because the meteorites are a complex mix of organic and inorganic materials, some with sizes similar to those of nanotubes.

“Nonetheless, our experiments suggest that such materials could have formed in interstellar space,” Zega said. “If they survived the journey to our local part of the galaxy where our solar system formed some 4.5 billion years ago, then they could be preserved inside of the material that was left over.”

Zega said a prime example of such leftover material is Bennu, a carbonaceous near-Earth asteroid from which NASA’s UArizona-led OSIRIS-REx mission scooped up a sample in October 2020. Scientists are eagerly awaiting the arrival of that sample, scheduled for 2023.  

“Asteroid Bennu could have preserved these materials, so it is possible we may find nanotubes in them,” Zega said.

Here’s a link to and a citation for the paper,

Destructive Processing of Silicon Carbide Grains: Experimental Insights into the Formation of Interstellar Fullerenes and Carbon Nanotubes by Jacob J. Bernal, Thomas J. Zega, and Lucy M. Ziurys. J. Phys. Chem. A 2022, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acs.jpca.2c01441 Publication Date:June 27, 2022 © 2022 American Chemical Society

This paper is behind a paywall.

Efficient hydrogen evolution reaction with graphene-based NiSe2 nanocrystalline array

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Should this work make its way from the laboratory to the market it could prove helpful in the drive to move away from fossil fuels, from a July 15, 2022 news item on Nanowerk,

In the face of low electrolytic water splitting catalytic activity, the development of efficiency and stable electrolytic catalyst for hydrogen evolution reaction is critical necessary. Moreover, the rather high price with insufficient supply of noble mental namely platinum and palladium has become the obstacle of their large-scale applications.

A research group of Lixu Lei from Southeast University [China] and Fajun Li from Suzhou University just reported a novel graphene based NiSe2 [nickel diselenide] nanocrystalline array prepared through a two-step microwave and subsequent selenization treatment. They found their unique structural advantages —— the ultrafine uniform dispersion of NiSe2 nanocrystallines in the reduced graphite oxide as substrate has an additional synergistic effect on promoting the conductivity and stability.

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A July 15, 2022 Higher Education Press news release on EurekAlert, which originated the news item, provides more detail about the work,

Nickel selenide electrocatalysts for hydrogen evolution reaction with high efficiency and low-cost, has favorable potential future application prospect. Nevertheless, the high overpotential and poor stability limited their practical applications. Carbon materials including graphene, carbon nanotubes etc. possess extraordinary thermal stability and electric conductivity, can be ideal protective skeleton structures of electrocatalysts. By combining the NiSe2 nanoparticles with graphene sheet in an in-situ growth manner assisted with microwave irradiation, the electrocatalytic performance of hydrogen evolution reaction was optimized remarkably in this work.

The electrocatalytic activity for hydrogen evolution reaction of the composite proven can reach up to 158 mV overpotential at 10 mA/cm2 and has an extremely stable performance in the 100 h H2 production test. These results provide a useful idea for the development of newly high efficiency electrocatalyst for hydrogen evolution reaction.

About Higher Education Press

Founded in May 1954, Higher Education Press Limited Company (HEP), affiliated with the Ministry of Education, is one of the earliest institutions committed to educational publishing after the establishment of P. R. China in 1949. After striving for six decades, HEP has developed into a major comprehensive publisher, with products in various forms and at different levels. Both for import and export, HEP has been striving to fill in the gap of domestic and foreign markets and meet the demand of global customers by collaborating with more than 200 partners throughout the world and selling products and services in 32 languages globally. Now, HEP ranks among China’s top publishers in terms of copyright export volume and the world’s top 50 largest publishing enterprises in terms of comprehensive strength.

The Frontiers Journals series published by HEP includes 28 English academic journals, covering the largest academic fields in China at present. Among the series, 13 have been indexed by SCI, 6 by EI, 2 by MEDLINE, 1 by A&HCI. HEP’s academic monographs have won about 300 different kinds of publishing funds and awards both at home and abroad.

About Frontiers in Energy

Frontiers in Energy, a peer-reviewed international journal launched in January 2007, presents a unique platform for reporting the most advanced research and strategic thinking on energy technology. The Journal publishes review and mini-review articles, original research articles, perspective, news & highlights, viewpoints, comments, etc. by individual researchers and research groups. The journal is strictly peer-reviewed and accepts only original submissions in English. The scope of the Journal covers (but not limited to): energy conversion and utilization; renewable energy; energy storage; hydrogen and fuel cells; carbon capture, utilization and storage; advanced nuclear technology; smart grids and microgrids; power and energy systems; power cells and electric vehicles; building energy conservation, energy and environment; energy economy and policy, etc. Interdisciplinary papers are encouraged.

Here’s a link to and a citation for the paper,

In situ growth of NiSe2 nanocrystalline array on graphene for efficient hydrogen evolution reaction by Shuai Ji, Changgan Lai, Huan Zhou, Helin Wang, Ling Ma, Cong Wang, Keying Zhang, Fajun Li & Lixu Lei. Frontiers in Energy (2022) DOI: https://doi.org/10.1007/s11708-022-0827-7 Published 10 June 2022

This paper is behind a paywall.

Extending a wig’s life with a nanocomposite

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A June 13, 2022 American Chemical Society (ACS) news release (also on EurekAlert) announces a nanocomposite that could make wigs last longer,

For some people, wigs are a fun and colorful fashion accessory, but for those with hair loss from alopecia or other conditions, they can provide a real sense of normalcy and boost self-confidence. Whether made from human or synthetic strands, however, most hairpieces lose their luster after being worn day after day. Now, researchers in ACS Applied Materials & Interfaces report a new way to make wigs more durable and long lasting.

Wigs come in all colors of the rainbow and in every style imaginable. Some cover the whole head, while others are “extensions,” sections of hair that clip onto existing locks to make them look fuller or longer. Hairpieces can be made of real human strands or synthetic materials, but either way, washing, UV exposure from the sun and repeated styling can cause these products to become dry and brittle. To extend the wearable life of wigs, some researchers have spray-coated a layer of graphene oxide on them, whereas other teams have immersed wig hairs in a keratin/halloysite nanocomposite. Because it’s difficult to cover an entire hairpiece with these methods, Guang Yang, Huali Nie and colleagues wanted to see if a nanocomposite applied with a tried-and-true approach for coating surfaces with ultrathin films — known as the Langmuir-Blodgett (LB) technique — could improve coverage and increase durability.

The researchers first developed a keratin and graphene oxide nanocomposite as the coating material. To coat hairs with the LB method, they dipped a few human or synthetic hairs into water in a special apparatus with moveable side barriers. After the nanocomposite was spread on the water’s surface with an atomizer, the barriers were moved inward to compress the film— like the trash compactor that almost crushed the heroes in the movie Star Wars. After 30 minutes, the researchers lifted the hairs out of the water, and as they did so, the film coated the locks.

Compared to the immersion technique, the LB method provided more coverage. In addition, hairs treated with the LB approach sustained less UV damage, were less prone to breakage and could hold more moisture than those that were simply immersed in the nanocomposite. They also dissipated heat better and generated less static electricity when rubbed with a rubber sheet. The researchers say that the method can be scaled up for use by companies that manufacture wigs.

The authors acknowledge funding from the Fundamental Research Funds for the Central Universities, the Shanghai Natural Science Foundation, the Shanghai Pujiang Program, the Natural Science Foundation of Shandong Province, and the Shanghai International Cooperative Project of the Belt and Road.

Here’s a link to and a citation for the paper,

High-Performance Wigs via the Langmuir–Blodgett Deposition of Keratin/Graphene Oxide Nanocomposite by Shan Du, Tiantian He, Huali Nie, and Guang Yang. ACS Appl. Mater. Interfaces 2022, 14, 23, 27233–27241 DOI: https://doi.org/10.1021/acsami.2c05965 Publication Date:June 3, 2022 Copyright © 2022 American Chemical Society

This paper is behind a paywall.