Graphene-based memory resistors show promise for brain-based computing

Graphene memristors open doors for biomimetic computing.

UNIVERSITY PARK, Pa. — As progress in traditional computing slows, new forms of computing are coming to the forefront. At Penn State, a team of engineers is attempting to pioneer a type of computing that mimics the efficiency of the brain’s neural networks while exploiting the brain’s analog nature.

Modern computing is digital, made up of two states, on-off or one and zero. An analog computer, like the brain, has many possible states. It is the difference between flipping a light switch on or off and turning a dimmer switch to varying amounts of lighting.

Neuromorphic or brain-inspired computing has been studied for more than 40 years, according to Saptarshi Das, the team leader and Penn State assistant professor of engineering science and mechanics.

What’s new is that as the limits of digital computing have been reached, the need for high-speed image processing, for instance for self-driving cars, has grown. The rise of big data, which requires types of pattern recognition for which the brain architecture is particularly well suited, is another driver in the pursuit of neuromorphic computing.

“We have powerful computers, no doubt about that, the problem is you have to store the memory in one place and do the computing somewhere else,” Das said.

The shuttling of this data from memory to logic and back again takes a lot of energy and slows the speed of computing. In addition, this computer architecture requires a lot of space. If the computation and memory storage could be located in the same space, this bottleneck could be eliminated.

“We are creating artificial neural networks, which seek to emulate the energy and area efficiencies of the brain,” explained Thomas Shranghamer, a doctoral student in the Das group and first author on a paper recently published in Nature Communications. “The brain is so compact it can fit on top of your shoulders, whereas a modern supercomputer takes up a space the size of two or three tennis courts.”

Like synapses connecting the neurons in the brain that can be reconfigured, the artificial neural networks the team is building can be reconfigured by applying a brief electric field to a sheet of graphene, the one-atomic-thick layer of carbon atoms. In this work they show at least 16 possible memory states, as opposed to the two in most oxide-based memristors, or memory resistors.

“What we have shown is that we can control a large number of memory states with precision using simple graphene field effect transistors,” Das said.

The team thinks that ramping up this technology to a commercial scale is feasible. With many of the largest semiconductor companies actively pursuing neuromorphic computing, Das believes they will find this work of interest.

In addition to Das and Shranghamer, the additional author on the paper, titled “Graphene Memristive Synapses for High Precision Neuromorphic Computing,” is Aaryan Oberoi, doctoral student in engineering science and mechanics.

The Army Research Office supported this work. The team has filed for a patent on this invention.

Globalized Economy making Water, Energy and Land Insecurity Worse a New Study by the University of Cambridge Shows …. Are We Surprised?

Credit: Pixabay/CC0 Public Domain

The first large-scale study of the risks that countries face from dependence on water, energy and land resources has found that globalisation may be decreasing, rather than increasing, the security of global supply chains.

Countries meet their needs for goods and services through domestic production and international trade. As a result, countries place pressures on natural resources both within and beyond their borders.

Researchers from the University of Cambridge used macroeconomic data to quantify these pressures. They found that the vast majority of countries and industrial sectors are highly exposed both directly, via domestic production, and indirectly, via imports, to over-exploited and insecure water, energy and land resources. However, the researchers found that the greatest resource risk is due to international trade, mainly from remote countries.

The researchers are calling for an urgent enquiry into the scale and source of consumed goods and services, both in individual countries and globally, as economies seek to rebuild in the wake of COVID-19. Their study, published in the journal Global Environmental Change, also invites critical reflection on whether globalisation is compatible with achieving sustainable and resilient supply chains.

Over the past several decades, the worldwide economy has become highly interconnected through globalisation: it is now not uncommon for each component of a particular product to originate from a different country. Globalisation allows companies to make their products almost anywhere in the world in order to keep costs down.

Many mainstream economists argue this offers countries a source of competitive advantage and growth potential. However, many nations impose demands on already stressed resources in other countries in order to satisfy their own high levels of consumption.

This interconnectedness also increases the amount of risk at each step of a global supply chain. For example, the UK imports 50% of its food. A drought, flood or any severe weather event in another country puts these food imports at risk.

Now, the researchers have quantified the global water, land and energy use of189 countries and shown that countries which are highly dependent on trade are potentially more at risk from resource insecurity, especially as climate change continues to accelerate and severe weather events such as droughts and floods become more common.

“There has been plenty of research comparing countries in terms of their water, energy and land footprints, but what hasn’t been studied is the scale and source of their risks,” said Dr. Oliver Taherzadeh from Cambridge’s Department of Geography. “We found that the role of trade has been massively underplayed as a source of resource insecurity—it’s actually a bigger source of risk than domestic production.”

To date, resource use studies have been limited to certain regions or sectors, which prevents a systematic overview of resource pressures and their source. This study offers a flexible approach to examining pressures across the system at various geographical and sectoral scales.

“This type of analysis hasn’t been carried out for a large number of countries before,” said Taherzadeh. “By quantifying the pressures that our consumption places on water, energy and land resources in far-off corners of the world, we can also determine how much risk is built into our interconnected world.”

The authors of the study linked indices designed to capture insecure water, energy, and land resource use, to a global trade model in order to examine the scale and sources of national resource insecurity from domestic production and imports.

Countries with large economies, such as the US, China and Japan, are highly exposed to water shortages outside their borders due to their volume of international trade. However, many countries in sub-Saharan Africa, such as Kenya, actually face far less risk as they are not as heavily networked in the global economy and are relatively self-sufficient in food production.

In addition to country-level data, the researchers also examined the risks associated with specific sectors. Surprisingly, one of the sectors identified in Taherzadeh’s wider research that had the most high-risk water and land use—among the top 1% of nearly 15,000 sectors analysed—was dog and cat food manufacturing in the U.S., due to its high demand for animal products.

“COVID-19 has shown just how poorly-prepared governments and businesses are for a global crisis,” said Taherzadeh. “But however bad the direct and indirect consequences of COVID-19 have been, climate breakdown, biodiversity collapse and resource insecurity are far less predictable problems to manage—and the potential consequences are far more severe. If the ‘green economic recovery’ is to respond to these challenges, we need radically rethink the scale and source of consumption.”

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Explore furtherResearchers examine food supply chain resiliency in the Pacific during COVID-19 pandemic

Provided by University of Cambridge 

Harley-Davidson officially spins off new electric bicycle company with stunning first model

This is it. Harley-Davidson has been teasing us with the prospect of their own in-house electric bicycles for over two years. And today the bar-and-shield motorcycle manufacturer has finally announced its new dedicated electric bicycle brand known as Serial 1 Cycle Company.

The brand’s name is an homage to the very first motorcycle ever built by Harley-Davidson in 1903, named “Serial Number One.”

Back then, motorcycles were essentially just bicycles with a small engine placed in front of the pedals.

And so it is fitting that the company’s first electric bicycle is a nod to that very first H-D motorcycle. Check out both in the video below to see how well they nailed the tribute.

As Serial 1 Cycle Company’s brand director Aaron Frank explained in a statement provided to Electrek:

When Harley-Davidson first put power to two wheels in 1903, it changed how the world moved, forever. Inspired by the entrepreneurial vision of Harley-Davidson’s founders, we hope to once again change how cyclists and the cycling-curious move around their world with a Serial 1 eBicycle.

The new e-bike brand from H-D actually began life as a skunkworks project in Harley-Davidson’s Product Development Center.

As the company explained, they began with “a small group of passionate motorcycle and bicycle enthusiasts working with a single focus to design and develop an eBicycle worthy of the Harley-Davidson name.”

Ultimately, they decided along with H-D to spin off the brand into a dedicated electric bicycle company that could focus purely on delivering a premium e-bike product and experience.

In addition to Aaron Frank, other major players from H-D’s in-house e-bike program that made the jump to Serial 1 Cycle Company include Jason Huntsman, president; Ben Lund, vice president; and Hannah Altenburg, lead brand marketing specialist.

Serial 1 will officially debut its first electric bicycle models for consumers in March 2021. For now, the company is showing off its first prototype model, which the brand describes as “a styling exercise, not necessarily intended for mass production.”

This prototype has been styled after that original 1903 Serial Number One motorcycle from Harley-Davidson. But interestingly, we can see that it shares the same frame as one of the original three electric bicycle prototypes that I spied last year at the 2019 EICMA Milan Motorcycle Show.

That means that while this specific styling likely won’t see showroom floors, the bike it is based on very well may be here this spring.

As we’ve previously seen, the design includes a mid-drive motor, a belt drive system that looks very much like a Gates Carbon Drive setup (which would make sense, as Harley-Davidson’s other belt-driven motorcycles including the all-electric LiveWire also uses belt drive systems from Gates), frame-integrated headlights and taillights, thru-axle wheel hubs, what appear to be Tektro dual-piston hydraulic disc brakes on 203 mm rotors, a Brooks leather saddle, and beautifully wrapped leather handgrips. 

I’m still left with many questions. Will these parts make it onto Serial 1 Cycle Company’s production models? What power level is the motor? What is the battery capacity? How much will the e-bikes cost?

For these questions and more, we still have no answers. But at least now we have a better idea of when to expect answers, and who we will be receiving them from. Stay tuned, because as soon as Serial 1 has more details for us, we’ll be back to share them with you.

FTC: We use income earning auto affiliate links. More.

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Researchers develop new atomic layer deposition process

Credit: CC0 Public Domain

A new way to deposit thin layers of atoms as a coating onto a substrate material at near room temperatures has been invented at The University of Alabama in Huntsville (UAH), a part of the University of Alabama System.

UAH postdoctoral research associate Dr. Moonhyung Jang got the idea to use an ultrasonic atomization technology to evaporate chemicals used in atomic layer deposition (ALD) while shopping for a home humidifier.

Dr. Jang works in the laboratory of Dr. Yu Lei, an associate professor in the Department of Chemical Engineering. The pair have published a paper on their invention that has been selected as an editor’s pick in the Journal of Vacuum Science & Technology A.

“ALD is a three-dimensional thin film deposition technique that plays an important role in microelectronics manufacturing, in producing items such as central processing units, memory and hard drives,” says Dr. Lei.

Each ALD cycle deposits a layer a few atoms deep. An ALD process repeats the deposition cycle hundreds or thousands of times. The uniformity of the thin films relies on a surface self-limiting reaction between the chemical precursor vapor and the substrates.

“ALD offers exceptional control of nanometer features while depositing materials uniformly on large silicon wafers for high volume manufacturing,” Dr. Lei says. “It is a key technique to produce powerful and small smart devices.”

While browsing online for a safe and easy-to-use home humidifier, Dr. Jang observed that humidifiers on the market use either direct heating at high temperature or ultrasonic atomizer vibration at room temperature to generate the water mist.

“Moon suddenly realized that the latter could be a safe and simple way to generate vapors for reactive chemicals that are thermally unstable,” says Dr. Lei.

“The next day, Moon came to discuss the idea and we designed the experiments to prove the concept in our research lab. The whole processes took almost a year. But the great idea came to Moon like a flash.”

ALD processes typically rely on heated gas-phase molecules that are evaporated from their solid or liquid form, similar to room humidifiers that use heat to vaporize water. Yet in that ALD process, some chemical precursors are not stable and can decompose before reaching a sufficient vapor pressure for ALD.

“In the past, many reactive chemicals were considered not suitable for ALD because of their low vapor pressure and because they are thermally unstable,” says Dr. Lei. “Our research found that the ultrasonic atomizer technique enabled evaporating the reactive chemicals at as low as room temperature.”

The UAH scientists’ ultrasound invention makes it possible to use a wide range of reactive chemicals that are thermally unstable and not suitable for direct heating.

“Ultrasonic atomization, as developed by our research group, supplies low vapor pressure precursors because the evaporation of precursors was made through ultrasonic vibrating of the module,” Dr. Lei says.

“Like the household humidifier, ultrasonic atomization generates a mist consisting of saturated vapor and micro-sized droplets,” he says. “The micro-sized droplets continuously evaporate when the mist is delivered to the substrates by a carrier gas.”

The process uses a piezo-electric ultrasonic transducer placed in a liquid chemical precursor. Once started, the transducer starts to vibrate a few hundred thousand times per second and generates a mist of the chemical precursor. The small liquid droplets in the mist are quickly evaporated in the gas manifold under vacuum and mild heat treatment, leaving behind an even coat of the deposition material.

“Using the room-temperature ultrasonic atomization reported by our manuscript, new ALD processes could be developed using low volatility and unstable precursors,” Dr. Lei says. “It will open a new window to many ALD processes.”

In their paper, the UAH researchers demonstrate proof of concept by comparing titanium oxide ALD using thermally evaporated and room-temperature ultrasonic atomized chemical precursors, respectively.

“The TiO₂ thin film quality is comparable,” says Dr. Lei.

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New chemistry for ultra-thin gas sensors

Researchers prove titanate nanotubes composites enhance photocatalysis of hydrogen – Better?

The titanate nanotubes (TNTs) composites enhanced the photocatalytic selectivity for H₂ generation from formic acid better than Pt/TiO₂. In addition, intensified electronic interactions occur between the components of TNTs and the Pt atoms in terms of the strong metal-support interaction, consequently influencing the behavior of photocatalysts. Therefore, the photocatalyst formed by Pt and TNTs has higher photocatalytic performance than TiO₂ from a 20% v/v methanol solution under UV and visible light irradiation. Credit: World Scientific Publishing

In a paper published in NANO, researchers from National Taiwan University examined the photocatalytic performances of titanate nanotubes (TNTs) against commonly-used titanium dioxide (TiO₂) and discovered superior performance of TNTs.

In the study, TiO₂ was used as a reference support compared with TNTs synthesized by a facile method. The results showed that Platinum (Pt/)TNTs fabricated using the microwave heating process enhanced the hydrogen evolution from methanol to a greater extent than Pt/TiO₂. The high surface area of TNTs can improve adsorption of methanol on the active site and prevent the formation of agglomerated fine Pt particles.

Additionally, the high surface area led to an increased contact area between Pt and Ti atoms, which enhanced the strong metal-support interaction and increased H₂ production performance. This is due to the absorption spectra of TNTs shifting toward the visible light region to a greater extent after loading Pt, thereby improving the selectivity of formic acid decomposition to CO₂. Therefore, Pt/TNTs, which have considerably high photocatalytic efficiency, are viable in further applications as promising photocatalysts.

The titanate nanotubes (TNTs) composites enhanced the photocatalytic selectivity for H₂ generation from formic acid better than Pt/TiO₂. In addition, intensified electronic interactions occur between the components of TNTs and the Pt atoms in terms of the strong metal-support interaction, consequently influencing the behavior of photocatalysts. Therefore, the photocatalyst formed by Pt and TNTs has higher photocatalytic performance than TiO₂ from a 20% v/v methanol solution under UV and visible light irradiation.

TNTs offer higher active surface area than TiO₂ nanoparticles. The high surface area provides short diffusion paths for electrons and holes, prompting them to transfer to the surface and reducing the recombination of electrons and holes. Also, X-ray Photoelectron Spectroscopy (XPS) results of the paper showed negative shifts of the Pt binding energies and positive shifts of Ti binding energies due to the strong metal-support interaction between Pt and TNTs. Thus, the remarkably high photocatalytic efficiency of TNT composites facilitates their application as promising photocatalysts.

Besides, it is worth noting that one mole of HCOOH decomposes into one mole of CO₂ and one mole of H₂, or one mole of CO and one mole of H₂O. Thus, it is important to increase the selectivity of formic acid decomposition for CO₂ evolution. The results show bare TNTs and Pt/TNTs resulted in lower CO generation than bare TiO₂ and Pt/TiO₂. This result may be attributed to the inability of CO to diffuse into the pores of TNTs because of the diameter difference, because the kinetic diameter of CO (0.38 nm) is larger than that of CO₂ (0.33 nm).

Will the different structure of the photocatalyst promote the photocatalytic selectivity of formic acid to H₂? The researchers prove tubular TNTs composites enhanced the photocatalytic hydrogen generation better than TiO₂.

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When the structure of tunneling nanotubes (TNTs) challenges the very concept of cell

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More information: Hsiu-Yu Chen et al, Microwave-Assisted Synthesis of Titanate Nanotubes Loaded with Platinum with Enhanced Selectivity for Photocatalytic H2 Evolution from Methanol, Nano (2020). DOI: 10.1142/S1793292020501295

Provided by World Scientific Publishing

Engineers create nanoparticles that deliver gene-editing tools to specific tissues and organs

Credit: CC0 Public Domain

One of the most remarkable recent advances in biomedical research has been the development of highly targeted gene-editing methods such as CRISPR that can add, remove, or change a gene within a cell with great precision. The method is already being tested or used for the treatment of patients with sickle cell anemia and cancers such as multiple myeloma and liposarcoma, and today, its creators Emmanuelle Charpentier and Jennifer Doudna received the Nobel Prize in chemistry.

While gene editing is remarkably precise in finding and altering genes, there is still no way to target treatment to specific locations in the body. The treatments tested so far involve removing blood stem cells or immune system T cells from the body to modify them, and then infusing them back into a patient to repopulate the bloodstream or reconstitute an immune response—an expensive and time-consuming process.

Building on the accomplishments of Charpentier and Doudna, Tufts researchers have for the first time devised a way to directly deliver gene-editing packages efficiently across the blood brain barrier and into specific regions of the brain, into immune system cells, or to specific tissues and organs in mouse models. These applications could open up an entirely new line of strategy in the treatment of neurological conditions, as well as cancer, infectious disease, and autoimmune diseases.

A team of Tufts biomedical engineers, led by associate professor Qiaobing Xu, sought to find a way to package the gene editing “kit” so it could be injected to do its work inside the body on targeted cells, rather than in a lab.

They used lipid nanoparticles (LNPs)—tiny “bubbles” of lipid molecules that can envelop the editing enzymes and carry them to specific cells, tissues, or organs. Lipids are molecules that include a long carbon tail, which helps give them an “oily” consistency, and a hydrophilic head, which is attracted to a watery environment.

There is also typically a nitrogen, sulfur, or oxygen-based link between the head and tail. The lipids arrange themselves around the bubble nanoparticles with the heads facing outside and the tails facing inward toward the center.

Xu’s team was able to modify the surface of these LNPs so they can eventually “stick” to certain cell types, fuse with their membranes, and release the gene-editing enzymes into the cells to do their work.

Making a targeted LNP takes some chemical crafting.

By creating a mix of different heads, tails, and linkers, the researchers can screen— first in the lab—a wide variety of candidates for their ability to form LNPs that target specific cells. The best candidates can then be tested in mouse models, and further modified chemically to optimize targeting and delivery of the gene-editing enzymes to the same cells in the mouse.

“We created a method around tailoring the delivery package for a wide range of potential therapeutics, including gene editing,” said Xu. “The methods draw upon combinatorial chemistry used by the pharmaceutical industry for designing the drugs themselves, but instead we are applying the approach to designing the components of the delivery vehicle.”

In an ingenious bit of chemical modeling, Xu and his team used a neurotransmitter at the head of some lipids to assist the particles in crossing the blood-brain barrier, which would otherwise be impermeable to molecule assemblies as large as an LNP.

The ability to safely and efficiently deliver drugs across the barrier and into the brain has been a long-standing challenge in medicine. In a first, Xu’s lab delivered an entire complex of messenger RNAs and enzymes making up the CRISPR kit into targeted areas of the brain in a living animal.

Some slight modifications to the lipid linkers and tails helped create LNPs that could deliver into the brain the small molecule antifungal drug amphotericin B (for treatment of meningitis) and a DNA fragment that binds to and shuts down the gene producing the tau protein linked to Alzheimer’s disease.

More recently, Xu and his team have created LNPs to deliver gene-editing packages into T cells in mice. T cells can help in the production of antibodies, destroy infected cells before viruses can replicate and spread, and regulate and suppress other cells of the immune system.

The LNPs they created fuse with T cells in the spleen or liver—where they typically reside—to deliver the gene-editing contents, which can then alter the molecular make-up and behavior of the T cell. It’s a first step in the process of not just training the immune system, as one might do with a vaccine, but actually engineering it to fight disease better.

Xu’s approach to editing T cell genomes is much more targeted, efficient, and likely to be safer than methods tried so far using viruses to modify their genome.

“By targeting T cells, we can tap into a branch of the immune system that has tremendous versatility in fighting off infections, protecting against cancer, and modulating inflammation and autoimmunity,” said Xu.

Xu and his team explored further the mechanism by which LNPs might find their way to their targets in the body. In experiments aimed at cells in the lungs, they found that the nanoparticles picked up specific proteins in the bloodstream after injection.

The proteins, now incorporated into the surface of the LNPs, became the main component that helped the LNPs to latch on to their target. This information could help improve the design of future delivery particles.

While these results have been demonstrated in mice, Xu cautioned that more studies and clinical trials will be needed to determine the efficacy and safety of the delivery method in humans.

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Explore furtherNovel drug delivery particles use neurotransmitters as a ‘passport’ into the brain

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More information: Xuewei Zhao et al. Imidazole‐Based Synthetic Lipidoids for In Vivo mRNA Delivery into Primary T Lymphocytes, Angewandte Chemie International Edition (2020). DOI: 10.1002/anie.202008082Journal information:Angewandte Chemie International EditionProvided by Tufts University

Graphene microbubbles make perfect lenses – And Much More … Drug Delivery .. Water Treatment

In situ optical microscopic images showing the process of the microbubble generation and elimination. Credit: H. Lin et al

Tiny bubbles can solve large problems. Microbubbles—around 1-50 micrometers in diameter—have widespread applications. They’re used for drug delivery, membrane cleaning, biofilm control, and water treatment. They’ve been applied as actuators in lab-on-a-chip devices for microfluidic mixing, ink-jet printing, and logic circuitry, and in photonics lithography and optical resonators. And they’ve contributed remarkably to biomedical imaging and applications like DNA trapping and manipulation.

Given the broad range of applications for microbubbles, many methods for generating them have been developed, including air stream compression to dissolve air into liquid, ultrasound to induce bubbles in water, and laser pulses to expose substrates immersed in liquids. However, these bubbles tend to be randomly dispersed in liquid and rather unstable.

According to Baohua Jia, professor and founding director of the Centre for Translational Atomaterials at Swinburne University of Technology, “For applications requiring precise bubble position and size, as well as high stability—for example, in photonic applications like imaging and trapping—creation of bubbles at accurate positions with controllable volume, curvature, and stability is essential.” Jia explains that, for integration into biological or photonic platforms, it is highly desirable to have well controlled and stable microbubbles fabricated using a technique compatible with current processing technologies.

Balloons in graphene

Jia and fellow researchers from Swinburne University of Technology recently teamed up with researchers from National University of Singapore, Rutgers University, University of Melbourne, and Monash University, to develop a method to generate precisely controlled graphene microbubbles on a glass surface using laser pulses. Their report is published in the peer-reviewed, open-access journal, Advanced Photonics.

Photonic jet focused by a graphene oxide microbubble lens. Credit: H. Lin et al., doi 10.1117/1.AP.2.5.055001

The group used graphene oxide materials, which consist of graphene film decorated with oxygen functional groups. Gases cannot penetrate through graphene oxide materials, so the researchers used laser to locally irradiate the graphene oxide film to generate gases to be encapsulated inside the film to form microbubbles—like balloons. Han Lin, Senior Research Fellow at Swinburne University and first author on the paper, explains, “In this way, the positions of the microbubbles can be well controlled by the laser, and the microbubbles can be created and eliminated at will. In the meantime, the amount of gases can be controlled by the irradiating area and irradiating power. Therefore, high precision can be achieved.”

Such a high-quality bubble can be used for advanced optoelectronic and micromechanical devices with high precision requirements.

The researchers found that the high uniformity of the graphene oxide films creates microbubbles with a perfect spherical curvature that can be used as concave reflective lenses. As a showcase, they used the concave reflective lenses to focus light. The team reports that the lens presents a high-quality focal spot in a very good shape and can be used as light source for microscopic imaging.

Lin explains that the reflective lenses are also able to focus light at different wavelengths at the same focal point without chromatic aberration. The team demonstrates the focusing of a ultrabroadband white light, covering visible to near-infrared range, with the same high performance, which is particularly useful in compact microscopy and spectroscopy.

Jia remarks that the research provides “a pathway for generating highly controlled microbubbles at will and integration of graphene microbubbles as dynamic and high precision nanophotonic components for miniaturized lab-on-a-chip devices, along with broad potential applications in high resolution spectroscopy and medical imaging.”

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Monolayer transition metal dichalcogenide lens for high resolution imaging

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More information: Han Lin et al, Near-perfect microlenses based on graphene microbubbles, Advanced Photonics (2020). DOI: 10.1117/1.AP.2.5.055001

Provided by SPIE

Mainstream EV Adoption: 5 Speedbumps to Overcome

** Article from the Visual Capitalist **

Many would agree that a global shift to electric vehicles (EV) is an important step in achieving a carbon-free future. However, for various reasons, EVs have so far struggled to break into the mainstream, accounting for just 2.5% of global auto sales in 2019. 

To understand why, this infographic from Castrol identifies the five critical challenges that EVs will need to overcome. All findings are based on a 2020 survey of 10,000 consumers, fleet managers, and industry specialists across eight significant EV markets. 

The Five Challenges to EV Adoption

Cars have relied on the internal combustion engine (ICE) since the early 1900s, and as a result, the ownership experience of an EV can be much more nuanced. This results in the five critical challenges we examine below. 

Challenge #1: Price

The top challenge is price, with 63% of consumers believing that EVs are beyond their current budget. Though many cheaper EV models are being introduced, ICE vehicles still have the upper hand in terms of initialaffordability. Note the emphasis on “initial”, because over the long term, EVs may actually be cheaper to maintain. 

Taking into account all of the running and maintenance costs of [an EV], we have already reached relative cost parity in terms of ownership.

—President, EV consultancy, U.S.

For starters, an EV drivetrain has significantly fewer moving parts than an ICE equivalent, which could result in lower repair costs. Government subsidies and the cost of electricity are other aspects to consider. 

So what is the tipping price that would convince most consumers to buy an EV? According to Castrol, it differs around the world. 

Country	EV Adoption Tipping Price ($)
Japan	$42,864
China	$41,910
Germany	$38,023
Norway	$36,737
U.S.	$35,765
France	$31,820
India	$30,572
UK	$29,883
Global Average	$35,947

Many budget-conscious buyers also rely on the used market, in which EVs have little presence. The rapid speed of innovation is another concern, with 57% of survey respondents citing possible depreciation as a factor that prevented them from buying an EV. 

Challenge #2: Charge Time

Most ICE vehicles can be refueled in a matter of minutes, but there is much more uncertainty when it comes to charging an EV. 

Using a standard home charger, it takes 10-20 hours to charge a typical EV to 80%. Even with an upgraded fast charger (3-22kW power), this could still take up to 4 hours. The good news? Next-gen charging systems capable of fully charging an EV in 20 minutes are slowly becoming available around the world. 

Similar to the EV adoption tipping price, Castrol has also identified a charge time tipping point—the charge time required for mainstream EV adoption. 

Country	Charge Time Tipping Point (minutes)
India	35
China	34
U.S.	30
UK	30
Norway	29
Germany	29
Japan	29
France	27
Global Average	31

If the industry can achieve an average 31 minute charge time, EVs could reach $224 billion in annual revenues across these eight markets alone. 

Challenge #3: Range

Over 70% of consumers rank the total range of an EV as being important to them. However, today’s affordable EV models (below the average tipping price of $35,947) all have ranges that fall under 200 miles. 

Traditional gas-powered vehicles, on the other hand, typically have a range between 310-620 miles. While Tesla offers several models boasting a 300+ mile range, their purchase prices are well above the average tipping price. 

For the majority of consumers to consider an EV, the following range requirements will need to be met by vehicle manufacturers.

Country	Range Tipping Point (miles)
U.S.	321
Norway	315
China	300
Germany	293
France	289
Japan	283
UK	283
India	249
Global Average	291

Fleet managers, those who oversee vehicles for services such as deliveries, reported a higher average EV tipping range of 341 miles. 

Challenge #4: Charging Infrastructure

Charging infrastructure is the fourth most critical challenge, with 64% of consumers saying they would consider an EV if charging was convenient.

Similar to charge times, there is much uncertainty surrounding infrastructure. For example, 65% of consumers living in urban areas have a charging point within 5 miles of their home, compared to just 26% for those in rural areas. 

Significant investment in public charging infrastructure will be necessary to avoid bottlenecks as more people adopt EVs. China is a leader in this regard, with billions spent on EV infrastructure projects. The result is a network of over one million charging stations, providing 82% of Chinese consumers with convenient access. 

Challenge #5: Vehicle Choice

The least important challenge is increasing the variety of EV models available. This issue is unlikely to persist for long, as industry experts believe 488 unique models will exist by 2025. 

Despite variety being less influential than charge times or range, designing models that appeal to various consumer niches will likely help to accelerate EV adoption. Market research will be required, however, because attitudes towards EVs vary by country.

Country	Consumers Who Believe EVs Are More Fashionable Than ICE Vehicles (%)
India	70%
China	68%
France	46%
Germany	40%
UK	40%
Japan	39%
U.S.	33%
Norway	31%
Global Average	48%

A majority of Chinese and Indian consumers view EVs more favorably than traditional ICE vehicles. This could be the result of a lower familiarity with cars in general—in 2000, for example, China had just four million cars spread across its population of over one billion. 

EVs are the least alluring in the U.S. and Norway, which coincidentally have the highest GDP per capita among the eight countries surveyed. These consumers may be accustomed to a higher standard of quality as a result of their greater relative wealth. 

So When Do EVs Become Mainstream?

As prices fall and capabilities improve, Castrol predicts a majority of consumers will consider buying an EV by 2024. Global mainstream adoption could take slightly longer, arriving in 2030. 

Caution should be exhibited, as these estimates rely on the five critical challenges being solved in the short-term future. This hinges on a number of factors, including technological change, infrastructure investment, and a shift in consumer attitudes. 

New challenges could also arise further down the road. EVs require a significant amount of minerals such as copper and lithium, and a global increase in production could put strain on the planet’s limited supply.