Lawrence Berkeley National Lab scientists grow spiraling new Crystal material Which could yield unique optical, electronic and thermal properties, including super conductivity SuperChem

UC Berkeley and Berkeley Lab researchers created a new crystal built of a spiraling stack of atomically thin 

UC Berkeley and Berkeley Lab researchers created a new crystal built of a spiraling stack of atomically thin germanium sulfide sheets. Credit: UC Berkeley image by Yin Liu

With a simple twist of the fingers, one can create a beautiful spiral from a deck of cards. In the same way, scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory (Berkeley Lab) have created new inorganic crystals made of stacks of atomically thin sheets that unexpectedly spiral like a nanoscale card deck.

Their surprising structures, reported in a new study appearing online Wednesday, June 20, in the journal Nature, may yield unique optical, electronic and thermal properties, including superconductivity, the researchers say.

These helical crystals are made of stacked layers of germanium sulfide, a semiconductor material that, like graphene, readily forms sheets that are only a few atoms or even a single atom thick. Such “nanosheets” are usually referred to as “2-D materials.”

“No one expected 2-D materials to grow in such a way. It’s like a surprise gift,” said Jie Yao, an assistant professor of materials science and engineering at UC Berkeley. “We believe that it may bring great opportunities for materials research.”

While the shape of the crystals may resemble that of DNA, whose helical structure is critical to its job of carrying genetic information, their underlying structure is actually quite different. Unlike “organic” DNA, which is primarily built of familiar atoms like carbon, oxygen and hydrogen, these “inorganic” crystals are built of more far-flung elements of the periodic table—in this case, sulfur and germanium. And while organic molecules often take all sorts of zany shapes, due to unique properties of their primary component, carbon, inorganic molecules tend more toward the straight and narrow.

To create the twisted structures, the team took advantage of a crystal defect called a screw dislocation, a “mistake” in the orderly crystal structure that gives it a bit of a twisting force. This “Eshelby Twist,” named after scientist John D. Eshelby, has been used to create nanowires that spiral like pine trees. But this study is the first time the Eshelby Twist has been used to make crystals built of stacked 2-D layers of an atomically thin semiconductor.

The helical crystals may yield surprising new properties, like superconductivity. Credit: UC Berkeley image by Yin Liu

“Usually, people hate defects in a material—they want to have a perfect crystal,” said Yao, who also serves as a faculty scientist at Berkeley Lab. “But it turns out that, this time, we have to thank the defects. They allowed us to create a natural twist between the material layers.”

In a major discovery last year, scientists reported that graphene becomes superconductive when two atomically thin sheets of the material are stacked and twisted at what’s called a “magic angle.” While other researchers have succeeded at stacking two layers at a time, the new paper provides a recipe for synthesizing stacked structures that are hundreds of thousands or even millions of layers thick in a continuously twisting fashion.

“We observed the formation of discrete steps in the twisted crystal, which transforms the smoothly twisted crystal to circular staircases, a new phenomenon associated with the Eshelby Twist mechanism,” said Yin Liu, co-first author of the paper and a graduate student in materials science and engineering at UC Berkeley. “It’s quite amazing how interplay of materials could result in many different, beautiful geometries.”

By adjusting the material synthesis conditions and length, the researchers could change the angle between the layers, creating a twisted structure that is tight, like a spring, or loose, like an uncoiled Slinky. And while the research team demonstrated the technique by growing helical crystals of germanium sulfide, it could likely be used to grow layers of other materials that form similar atomically thin layers.

“The twisted structure arises from a competition between stored energy and the energy cost of slipping two material layers relative to one another,” said Daryl Chrzan, chair of the Department of Materials Science and Engineering and senior theorist on the paper. “There is no reason to expect that this competition is limited to germanium sulfide, and similar structures should be possible in other 2-D material systems.”

“The twisted behavior of these layered materials, typically with only two layers twisted at different angles, has already showed great potential and attracted a lot of attention from the physics and chemistry communities. Now, it becomes highly intriguing to find out, with all of these twisted layers combined in our new material, if will they show quite different material properties than regular stacking of these materials,” Yao said. “But at this moment, we have very limited understanding of what these properties could be, because this form of material is so new. New opportunities are waiting for us.”

Explore further

Research team discovers perfectly imperfect twist on nanowire growth

 

Plastic Gets a Do-Over: Breakthrough Discovery Recycles Plastic From the Inside Out

A 2015 investigation that estimates there are between 4.8 trillion and 12.7 trillion pieces of plastic entering the ocean every year.

Scientists from Berkeley Lab have made a next-generation plastic that can be recycled again and again into new materials of any color, shape, or form.

Plastic pollution in the world’s oceans may have a $2.5 trillion impact, negatively affecting “almost all marine ecosystem services,” including areas such as fisheries, recreation and heritage. But a breakthrough from scientists at Berkeley Lab could be the solution the planet needs for this eye-opening problem – recyclable plastics.

The study, published in Nature Chemistry, details how the researchers were able to discover a new way to assemble the plastics and reuse them “into new materials of any color, shape, or form.”

Most plastics were never made to be recycled,” said lead author Peter Christensen, a postdoctoral researcher at Berkeley Lab’s Molecular Foundry, in the statement. “But we have discovered a new way to assemble plastics that takes recycling into consideration from a molecular perspective.”

Known as poly(diketoenamine), or PDK, the new type of plastic material could help stem the tide of plastics piling up at recycling plants, as the bonds PDK forms are able to be reversed via a simple acid bath, the researchers believe.

Poly(diketoenamine)s ‘click’ together from a wide variety of triketones and aromatic or aliphatic amines, yielding only water as a by-product,” the study’s abstract reads.

“Recovered monomers can be re-manufactured into the same polymer formulation, without loss of performance, as well as other polymer formulations with differentiated properties. The ease with which poly(diketoenamine)s can be manufactured, used, recycled and re-used—without losing value—points to new directions in designing sustainable polymers with minimal environmental impact.”

Unlike conventional plastics, the monomers of PDK plastic could be recovered and freed from any compounded additives simply by dunking the material in a highly acidic solution. (Credit: Peter Christensen et al./Berkeley Lab)

A byproduct of petroleum, plastic is inherently made up of molecules known as polymers that are composed of carbon-containing compounds known as monomers. Once chemicals are added to the plastic for use and consumption, the monomers bind with the chemicals and make it difficult to be processed at recycling plants, the researchers said.

Circular plastics and plastics upcycling are grand challenges,” said Brett Helms, a staff scientist in Berkeley Lab’s Molecular Foundry, in the statement. “We’ve already seen the impact of plastic waste leaking into our aquatic ecosystems, and this trend is likely to be exacerbated by the increasing amounts of plastics being manufactured and the downstream pressure it places on our municipal recycling infrastructure.”

Though PDK only exists in the lab currently (meaning products won’t be available for purchase for some time), the researchers are nonetheless excited by what they’ve discovered and the potential positive impact it could have.

“With PDKs, the immutable bonds of conventional plastics are replaced with reversible bonds that allow the plastic to be recycled more effectively,” Helms added. “We’re interested in the chemistry that redirects plastic lifecycles from linear to circular. We see an opportunity to make a difference for where there are no recycling options.”

Plastic recycling figures are trending down, making breakthroughs in recyclable plastic all the more important. According to the latest publicly available data, only 9.1 percent of the plastic created in the U.S. in 2015 was recycled, down from 9.5 percent in 2014, according to the EPA.

Last month, a separate study estimated that the pollution caused by plastics in the world’s oceans amounted to a $2.5 trillion problem that every country in the world has to deal with. The estimate did not take into account the impact on sectors of the global economy such as tourism, transport, fisheries and human health, the researchers wrote.

An ecosystem impact analysis demonstrates that there is global evidence of impact with medium to high frequency on all subjects, with a medium to high degree of irreversibility,” the study’s abstract reads, with the researchers adding that they looked at nearly 1,200 data points to come up with their conclusions.

Despite several efforts of countries around the world to reduce or stop the use of plastic altogether, the amount of plastic in the world’s oceans is increasing, and spreading across the planet.

A separate study, published in Nature on April 16, is the first study “to confirm a significant increase in open ocean plastics in recent decades,” going back nearly 60 years. Researchers found a plastic bag that had been snared on Ireland’s coast since 1965 and is possibly the first piece of plastic pollution ever found, according to the BBC.

Article Re-Posted from Chris Ciaccia of Fox Science News

Why Do Most Science Startups Fail? Here’s Why …

“We need to get a lot better at bridging that gap between discovery and commercialization”

G. Satell – Inc. Magazine

It seems like every day we see or hear about a breakthrough new discovery that will change everything. Some, like perovskites in solar cells and CRISPR are improvements on existing technologies. Others, like quantum computing and graphene promise to open up new horizons encompassing many applications. Still others promise breakthroughs in Exciting Battery Technology Breakthrough News — Is Any Of It Real? or Beyond lithium — the search for a better battery

Nevertheless, we are still waiting for a true market impact. Quantum computing and graphene have been around for decades and still haven’t hit on their “killer app.” Perovskite solar cells and CRISPR are newer, but haven’t really impacted their industries yet. And those are just the most prominent examples.

The problem isn’t necessarily with the discoveries themselves, many of which are truly path-breaking, but that there’s a fundamental difference between discovering an important new phenomenon in the lab and creating value in the marketplace.

“We need to get a lot better at bridging that gap. To do so, we need to create a new innovation ecosystem for commercializing science.”

The Valley Of Death And The Human Problem

The gap between discovery and commercialization is so notorious and fraught with danger that it’s been unaffectionately called the “Valley of Death.” Part of the problem is that you can’t really commercialize a discovery, you can only commercialize a product and those are two very different things.

The truth is that innovation is never a single event, but a process of discovery, engineering and transformation. After something like graphene is discovered in the lab, it needs to be engineered into a useful product and then it has to gain adoption by winning customers in the marketplace. Those three things almost never happen in the same place.

So to bring an important discovery to market, you first need to identify a real world problem it can solve and connect to engineers who can transform it into a viable product or service. Then you need to find customers who are willing to drop whatever else they’ve been doing and adopt it on a large scale. That takes time, usually about 30 years.

The reason it takes so long is that there is a long list of problems to solve. To create a successful business based on a scientific discovery, you need to get scientists to collaborate effectively with engineers and a host of specialists in other areas, such as manufacturing, distribution and marketing. Those aren’t just technology problems, those are human problems. Being able to collaborate effectively is often the most important competitive advantage.

Wrong Industry, Wrong Application

One of the most effective programs for helping to bring discoveries out of the lab is I-Corps. First established by the National Science Foundation (NSF) to help recipients of SBIR grants identify business models for scientific discoveries, it has been such an extraordinary success that the US Congress has mandated its expansion across the federal government.

Based on Steve Blank’s lean startup methodology, the program aims to transform scientists into entrepreneurs. It begins with a presentation session, in which each team explains the nature of their discovery and its commercial potential. It’s exciting stuff, pathbreaking science with real potential to truly change the world.

The thing is, they invariably get it wrong. Despite their years of work to discover something of significance and their further efforts to apply and receive commercialization grants from the federal government, they fail to come up with a viable application in an industry that wants what they have to offer. 

Ironically, much of the success of the I-Corps program is due to these early sessions. Once they realize that they are on the wrong track, they embark on a crash course of customer discovery, interviewing dozens — and sometimes hundreds — of customers in search of a business model that actually has a chance of succeeding.

What’s startling about the program is that, without it, scientists with important discoveries often wasted years trying to make a business work that never really had a chance in the first place.

The Silicon Valley Myth

Much of the success of Silicon Valley has been based on venture-funded entrepreneurship. Startups with an idea to change the world create an early stage version of the product they want to launch, show it to investors and get funding to bring it to market. Just about every significant tech company was started this way.

Yet most of the success of Silicon Valley has been based on companies that sell either software or consumer gadgets, which are relatively cheap and easy to rapidly prototype. Many scientific startups, however, do not fit into this category. Often, they need millions of dollars to build a prototype and then have to sell to industrial companies with long lead times.

The myth of Silicon Valley is that venture-funded entrepreneurship is a generalizable model that can be applied to every type of business. It is not. In fact, it is a specific model that was conceived in a specific place at a specific time to fund mature technologies for specific markets. It’s not a solution that fits every problem.

The truth is that venture funds are very adept with assessing market risk, but not so good at taking on technology risk, especially in hard sciences. That simply isn’t what they were set up to do.

We Need A New Innovation Ecosystem For Science Entrepreneurship

In 1945, Vannevar Bush delivered a report, Science, The Endless Frontier, to President Truman, in which he made the persuasive argument that expanding the nation’s scientific capacity will expand its economic capacity and well being. His call led, ultimately, to building America’s scientific infrastructure, including programs like the NSF and the National Institutes of Health (NIH).

It was Bush’s vision that made America a technological superpower. Grants from federal agencies to scientists enabled them to discover new knowledge. Then established businesses and, later, venture backed entrepreneurs would then take those discoveries to bring new products and services to market.

Look at any industry today and its most important technologies were largely shaped by investment from the federal government. Today, however, the challenges are evolving. We’re entering a new era of innovation in which technologies like genomics, nanotechnology and robotics are going to reshape traditional industries like energy, healthcare and manufacturing.

That’s exciting, but also poses new challenges, because these technologies are ill-suited to the Silicon Valley model of venture-funded entrepreneurship and need help to them get past the Valley of Death. So we need to build a new innovation ecosystem on top of the scientific architecture Bush created for the post-war world.

There have been encouraging signs. New programs like I-Corps, the Manufacturing Institutes, Cyclotron Road and Chain Reaction are beginning to help fill the gap.

Still much more needs to be done, especially at the state and local level to help build regional hubs for specific industries, if we are going to be nearly as successful in the 21st century as were were in the 20th.

Sugar-coated “nanosheets” selectively targets pathogens – Functions like flypaper selectively binding with viruses, bacteria, and other pathogens (Lawrence Berkeley Laboratory)

A molecular model of a peptoid nanosheet that shows loop structures in sugars (orange) that bind to Shiga toxin (shown as a five-color bound structure at upper right). Credit: Berkeley Lab

Researchers have developed a process for creating ultrathin, self-assembling sheets of synthetic materials that can function like designer flypaper in selectively binding with viruses, bacteria, and other pathogens.

In this way the new platform, developed by a team led by scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), could potentially be used to inactivate or detect pathogens.

The team, which also included researchers from New York University, created the synthesized nanosheets at Berkeley Lab’s Molecular Foundry, a nanoscale science center, out of self-assembling, bio-inspired polymers known as peptoids. The study was published earlier this month in the journal ACS Nano.

The sheets were designed to present simple sugars in a patterned way along their surfaces, and these sugars, in turn, were demonstrated to selectively bind with several proteins, including one associated with the Shiga toxin, which causes dysentery. Because the outside of our cells are flat and covered with sugars, these 2-D nanosheets can effectively mimic cell surfaces.

“It’s not just a ‘lock and key’ – it’s like Velcro, with a bunch of little loops that converge on the target protein together,” said Ronald Zuckermann, a scientist at the Molecular Foundry who led the study. “Now we can mimic a nanoscale feature that is ubiquitous in biology.”

3-D-printed model of a peptoid nanosheet, showing patterned rows of sugars. Credit: Berkeley Lab

He noted that numerous pathogens, from the flu virus to cholera bacteria, bind to sugars on cell surfaces. So picking the right sugars to bind to the peptoid nanosheets, in the right distributions, can determine which pathogens will be drawn to them.

“The chemistry we’re doing is very modular,” Zuckermann added. “We can ‘click on’ different sugars, and present them on a well-defined, planar surface. We can control how far apart they are from each other. We can do this with pretty much any sugar.”

The peptoid platform is also more rugged and stable compared to natural biomolecules, he said, so it can potentially be deployed into the field for tests of bioagents by military personnel and emergency responders, for example.

And peptoids – an analog to peptides in biology that are chains of amino acids – are cheap and easy-to-make polymers.

“The chemical information that instructs the molecules to spontaneously assemble into the sugar-coated sheets is programmed into each molecule during its synthesis,” Zuckermann said. “This work demonstrates our ability to readily engineer sophisticated biomimetic nanostructures by direct control of the polymer sequence.”

A 3-D ribbon model representing a protein subunit of the Shiga toxin. The bacteria-produced toxin causes dysentery in humans. Credit: Wikimedia Commons

The sugar-coated nanosheets are made in a liquid solution. Zuckermann said if the nanosheets are used to protect someone from becoming exposed to a pathogen, he could envision the use of a nasal spray containing the pathogen-binding nanosheets.

The nanosheets could also potentially be used in environmental cleanups to neutralize specific toxins and pathogens, and the sheets could potentially be scaled to target viruses like Ebola and bacteria like E. coli, and other pathogens.

In the latest study, the researchers confirmed that the bindings with the targeted proteins were successful by embedding a fluorescent dye in the sheets and attaching another fluorescent dye on the target proteins. A color change indicated that a protein was bound to the nanosheet.

The intensity of this color change can also guide researchers to improve them, and to discover new nanosheets that could target specific pathogens.

(From phys.org)

 Explore further: ‘Molecular Velcro’ may lead to cost-effective alternatives to natural antibodies

More information: Alessia Battigelli et al, Glycosylated Peptoid Nanosheets as a Multivalent Scaffold for Protein Recognition, ACS Nano (2018). DOI: 10.1021/acsnano.7b08018

Journal reference: ACS Nano  

Provided by: Lawrence Berkeley National Laboratory

 

America’s National Laboratories – 75 Breakthroughs We’ve Made that You May Not have Read About

America’s National Laboratories have been changing and improving the lives of millions of people for more than 75 years. Born at a time when the world faced a dire threat, the laboratories came together to advance science, safeguard the nation and protect our freedoms for generations to come. This network of Department of Energy Laboratories has grown into 17 facilities, working together as engines of prosperity and invention. As this list of breakthroughs attests, Laboratory discoveries have spawned industries, saved lives, generated new products, fired the imagination and helped to reveal the secrets of the universe. Rooted in the need to serve the public good and support the global community, the National Laboratories have put an American stamp on the last century of science. With equal ingenuity and tenacity, they are now engaged in innovating the future.

Download and read 75 Breakthroughs by America’s National Laboratories.

75 Breakthroughs

At America’s National Laboratories, we’ve …

Advanced supercomputing

The National Labs operate some of the most significant high performance computing resources available, including 32 of the 500 fastest supercomputers in the world. These systems, working at quadrillions of operations per second, model and simulate complex, dynamic systems – such as the nuclear deterrent – that would be too expensive, impractical or impossible to physically demonstrate. Supercomputers are changing the way scientists explore the evolution of our universe, climate change, biological systems, weather forecasting and even renewable energy.

Decoded DNA 

In 1990, the National Labs joined with the National Institutes of Health and other laboratories to kick off the Human Genome Project, an international collaboration to identify and map all of the genes of the human genome.

Brought the web to the United States 

National Lab scientists, seeking to share particle physics information, were first to install a web server in North America, kick-starting the development of the worldwide web as we know it.

Put eyes in the sky 

Vela satellites, first launched in 1963 to detect potential nuclear detonations, transformed the nascent U.S. space program. The satellites featured optical sensors and data processing, logic and power subsystems designed and created by National Labs.

Revolutionized medical diagnostics and treatment 

Researchers at the National Labs helped to develop the field of nuclear medicine, producing radioisotopes to diagnose and treat disease, designing imaging technology to detect cancer and developing software to target tumors while sparing healthy tissue.

Powered NASA spacecraft 

The National Labs built the enclosure for the radioisotope thermoelectric generators that fuel crafts such as Cassini and have begun producing plutonium-238 for future NASA missions.

Harnessed the power of the atom 

National Lab scientists and engineers have led the world in developing safe, efficient and emissions-free nuclear power. Starting with the first nuclear reactor to generate electricity, National Labs have been the innovation engine behind the peaceful use of nuclear energy. Today’s labs are supporting the next generation of nuclear power that will be available for the nation and world.

Brought safe water to millions 

Removing arsenic from drinking water is a global priority. A long-lasting particle engineered at a National Lab can now do exactly that, making contaminated water safe to drink. Another technology developed at a National Lab uses ultraviolet light to kill water-borne bacteria that cause dysentery, thus reducing child mortality in the developing world.

Filled the Protein Data Bank 

National Lab X-ray facilities have contributed a large portion of more than 100,000 protein structures in the Protein Data Bank. A protein’s structure reveals how it functions, helping scientists understand how living things work and develop treatments for disease. Almost all new medications that hit the market start with these data bank structures.

Invented new materials 

National Labs provide the theory, tools and techniques that offer industry revolutionary materials such as strong, lighter-weight metals and alloys that save fuel and maintenance costs and enable cleaner, more efficient engines.

Found life’s mystery messenger 

National Lab scientists discovered how genetic instructions are carried to the cell’s protein manufacturing center, where all of life’s processes begin. Subsequent light source research on the genetic courier, called messenger RNA, has revealed how the information is transcribed and how mistakes can cause cancer and birth defects.

Mapped the universe — and the dark side of the moon

Credit for producing 3D maps of the sky — and 400 million celestial objects — goes to National Lab scientists, who also developed a camera that mapped the entire surface of the moon.

Shed light on photosynthesis 

Ever wonder how plants turn sunlight into energy? National Lab scientists determined the path of carbon through photosynthesis, and today use X-ray laser technology to reveal how each step in the process is triggered by a single particle of light. This work helps scientists explore new ways to get sustainable energy from the sun.

Solved cultural mysteries 

The works of ancient mathematician Archimedes — written over by medieval monks and lost for millennia — were revealed to modern eyes thanks to the X-ray vision and light-source technology at National Labs. These studies also have revealed secrets of masterpiece paintings, ancient Greek vases and other priceless cultural artifacts.

Revolutionized accelerators 

A National Lab built and operated the first large-scale accelerator based on superconducting radio frequency technology. This more efficient technology now powers research machines for exploring the heart of matter, examining the properties of materials and providing unique information about the building blocks of life.

Revealed the secrets of matter 

Protons and neutrons were once thought to be indivisible. National Lab scientists discovered that protons and neutrons were made of even smaller parts, called quarks. Over time, experimenters identified six kinds of quarks, three types of neutrinos and the Higgs particle, changing our view of how the material world works.

Confirmed the Big Bang and discovered dark energy

National Lab detectors aboard a NASA satellite revealed the birth of galaxies in the echoes of the Big Bang. Dark energy — the mysterious something that makes up three-quarters of the universe and causes it to expand at an accelerating rate — also was discovered by National Lab cosmologists.

Discovered 22 elements 

The periodic table would be smaller without the National Labs. To date the National Labs have discovered: technetium, promethium, astatine, neptunium, plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium, lawrencium, rutherfordium, dubnium, seaborgium, flerovium, moscovium, livermorium, tennessine and oganesson.

Made refrigerators cool 

Next-generation refrigerators will likely put the freeze on harmful chemical coolants in favor of an environmentally friendly alloy, thanks to National Lab scientists.

Got the lead out 

Removing hazardous lead-based solders from the environment is a reality thanks to a lead-free alloy of tin-silver-copper developed at a National Lab. The lead-free solder has been licensed by more than 60 companies worldwide.

Invented a magic sponge to clean up oil spills

National Lab scientists used a nano technique to invent a new sponge that can absorb 90 times its own weight in oil from water. It can be wrung out to collect the oil and reused hundreds of times — and it can collect oil that has sunk below the surface, something previous technology couldn’t do.

Added the punch to additive manufacturing 

High-pressure gas atomization processing pioneered at a National Lab made possible the production of titanium and other metal-alloy powders used in additive manufacturing and powder metallurgy.

 

Created inexpensive catalysts 

Low-cost catalysts are key to efficient biomass refining. National Lab scientists created catalysts that are inexpensive and stable for biomass conversion. 

Created high-tech coatings to reduce friction 

National Lab scientists created ways to reduce wear and tear in machines from table fans to car engines all the way up to giant wind turbines, such as a diamond-like film that rebuilds itself as soon as it begins to break down — so that engines last longer and need fewer oil additives.

Put the jolt in the Volt 

Chevy’s Volt would not be able to cruise on battery power were it not for the advanced cathode technology that emerged from a National Lab. The same technology is sparking a revival of America’s battery manufacturing industry.

Cemented a new material 

National Lab scientists have developed a novel and versatile material that blends properties of ceramic and concrete to form a non-porous product that can do everything from seal oil w ells to insulate walls with extra fire protection. It even sets in cold weather.

Pioneered efficient power lines 

New kinds of power lines made from superconductors can carry electric current with no energy loss. Now deployed by National Lab scientists, these prototypes could usher in a new era of ultra-efficient power transmission.

Made early universe quark soup 

National Lab scientists used a particle collider to recreate the primordial soup of subatomic building blocks that last existed shortly after the Big Bang. The research is expanding scientists’ understanding of matter at extreme temperatures and densities.

Levitated trains with magnets 

Say goodbye to traffic jams. National Lab scientists developed a technology that uses the attractive and repulsive forces of magnets to levitate and propel trains. Maglev trains now ferry commuters in Japan and China and will be operational in other countries soon.

Developed efficient burners 

National Lab researchers developed cleaner-combusting oil burners, saving consumers more than $25 billion in fuel costs and keeping more than 160 megatons of carbon dioxide out of Earth’s atmosphere.

Improved automotive steel

A company with National Lab roots is pioneering a metal that weighs significantly less than regular steel, retains steel’s strength and malleability and can be fabricated without major modifications to the automotive manufacturing infrastructure.

Looked inside weapons

National Lab researchers created a device that could identify the contents of suspicious chemical and explosive munitions and containers, while minimizing risk to the people involved. The technology, which quickly identifies the chemical makeup of weapons, has been used to verify treaties around the world.

Pioneered nuclear safety modeling 

National Lab scientists began developing the Reactor Excursion and Leak Analysis Program (RELAP) to model nuclear reactor coolant and core behavior. Today, RELAP is used throughout the world and has been licensed for both nuclear and non-nuclear applications, including modeling of jet aircraft engines and fossil-fuel power plant components.

Identified good and bad cholesterol 

The battle against heart disease received a boost in the 1960s when National Lab research unveiled the good and bad sides of cholesterol. Today, diagnostic tests that detect both types of cholesterol save lives.

Unmasked a dinosaur killer 

Natural history’s greatest whodunit was solved in 1980 when a team of National Lab scientists pinned the dinosaurs’ abrupt extinction on an asteroid collision with Earth. Case closed.

Pitted cool roofs against carbon dioxide 

National Lab researchers and policy experts led the way in analyzing and implementing cool roofing materials, which reflect sunlight, lower surface temperature and slash cooling costs.

Squeezed fuel from microbes 

In a milestone that brings advanced biofuels one step closer to America’s gas tanks, National Lab scientists helped develop a microbe that can produce fuel directly from biomass.

Tamed hydrogen with nanoparticles 

To replace gasoline, hydrogen must be safely stored and easy to use, which has proven elusive. National Lab researchers have now designed a new pliable material using nanoparticles that can rapidly absorb and release hydrogen without ill effects, a major step in making fuel-cell powered cars a commercial reality.

Exposed the risk 

You can sleep easier thanks to National Lab research that quantified the health risk posed by radon gas in parts of the country. Subsequent EPA standards, coupled with radon detection and mitigation measures pioneered by a National Lab research team, prevent the naturally occurring gas from seeping into basements, saving thousands of lives every year.

Created a pocket-sized DNA sampler 

A tool that identifies the microbes in air, water and soil samples is fast becoming a workhorse in public health, medical and environmental cleanup projects. Developed by National Lab scientists, the credit-card-sized device pinpoints diseases that kill coral reefs and catalogs airborne bacteria over U.S. cities. It also was used to quickly categorize the oil-eating bacteria in the plumes of the Deepwater Horizon spill.

Fabricated the smallest machines

The world’s smallest synthetic motors — as well as radios, scales and switches that are 100,000 times finer than a human hair — were engineered at a National Lab. These and other forays into nanotechnology could lead to life-saving pharmaceuticals and more powerful computers.

Preserved the sounds of yesteryear 

National Lab scientists engineered a high-tech way to digitally reconstruct aging

sound recordings that are too fragile to play, such as Edison wax cylinders from the late 1800s. Archivists estimate that many of the millions of recordings in the world’s sound archives, including the U.S. Library of Congress, could benefit from the technology.

Exposed explosives 

A credit-card sized detector developed by National Lab scientists can screen for more than 30 kinds of explosives in just minutes. The detector, called ELITE, requires no po wer and is widely used by the military, law enforcement and security personnel.

Toughened airplanes 

A National Lab and industry technique for strengthening metal by bombarding it with laser pulses has saved the aircraft industry hundreds of millions of dollars in engine and aircraft maintenance expenses.

Simulated reality 

Trains, planes and automobiles — and thousands of other objects — are safer, stronger and better-designed thanks to computer simulation software, DYNA 3D, developed by National Lab researchers.

Detected the neutrino 

Starting with the Nobel-Prize winning discovery of the neutrino in 1956 by Fred Reines and Clyde Cowan Jr., National Lab researchers have made numerous contributions to neutrino physics and astrophysics.

Discovered gamma ray bursts

Sensors developed at the National Labs and placed aboard Vela satellites were used in the discovery of gamma-ray bursts (GRBs) in 1973. GRBs are extremely energetic explosions from distant galaxies. Scientists believe that most of these bursts consist of a narrow beam of intense radiation released when a rapidly rotating, high-mass star collapses to form a neutron star, a quark star or a black hole.

Created the first 100-Tesla magnetic field 

National Lab scientists achieved a 100.75-Tesla magnetic pulse in March 2012, setting a world record. The pulse was nearly 2 million times more powerful than Earth’s magnetic field. The 100-Tesla multi-shot magnet can be used over and over again without being destroyed by the force of the field it creates, and produces the most powerful non-destructive magnetic field in the world.

Froze smoke for hot uses 

National Labs researchers perfected aerogels, known as frozen smoke. They are one of the lightest solids ever made and have the highest heat resistance of any material tested. They also are fireproof and extraordinarily strong — able to support more than a thousand times their own weight. As a result of their heat resistance, aerogels are outstanding candidates for insulation in buildings, vehicles, filters and appliances.

Invented the cell sorter 

During the 1960s, a National Lab physicist invented a “cell sorter” — a novel device that works much like an ink jet printer, guiding a tiny flow of cell-containing droplets so cells of interest can be deflected for counting and study. Cell sorters are a vital tool for studying the biochemistry behind many diseases, including cancer and AIDS.

Ushered a domestic energy renaissance 

National Lab research jump-started the shale gas revolution by pointing the way to key technologies and methodologies for cost efficient extraction. An estimated $220 million in research and development expenditures on unconventional gas R&D from 1976 to 1992 have resulted in an estimated $100 billion in annual economic activity from shale gas production alone.

Enabled space exploration 

National Labs invented Laser-Induced Breakdown Spectroscopy (LIBS), the backbone of the device that allowed the Curiosity Rover to analyze material from Mars. Lab researchers also found the right combination of materials to make high-efficiency solar cells for spacecraft.

Sharply curtailed power plant air emissions 

National Lab scientists introduced some 20 innovative technologies — such as low nitrogen oxide (NOx) burners, flue gas desulfurization (scrubbers) and fluidized bed combustion — through the Clean Coal Technology Development Program that have deeply penetrated the marketplace, substantially controlled harmful power plant emissions and benefited energy production and air quality.

Made wind power mainstream 

Increasing wind turbine efficiency with high efficiency airfoils has reduced the cost of wind power by more than 80 percent over the last 30 years. Now deployed in wind farms nationwide, these turbines owe their existence to National Lab research.

Engineered smart windows 

National Lab scientists have created highly insulated windows that change color to modulate interior temperatures and lighting. If broadly installed, they could save about 5 percent of the nation’s total energy budget.

Delivered troops safely 

National Lab researchers have developed computer models that effectively manage the complex logistical tasks of deploying troops and equipment to distant destinations.

Channeled chips and hips 

Integrated circuits and artificial hips owe their success to a National Lab discovery that revealed how to change a material by injecting it with charged atoms, called ions. Ion channeling is now standard practice in industry and science.

Made 3D printing bigger and better 

A large-scale additive manufacturing platform developed by a National Lab and an industry partner printed 3D components 10 times larger and 200 times faster than previous processes. So far, the system has produced a 3D-printed sports car, SUV, house, excavator and aviation components.

Purified vaccines

National Lab researchers adapted nuclear separations technology to develop a zonal centrifuge used to purify vaccines, which reduces or eliminates unwanted side effects. Commercial centrifuges based on the invention produce vaccines for millions of people.

Built a better building 

A National Lab has built one of the world’s most energy efficient office buildings. The facility, operating as a living laboratory at a lab site, uses 50 percent less energy than required by commercial codes and only consumes energy produced by renewable power on or near the building.

Improved airport security 

Weapons, explosives, plastic devices and other concealed tools of terrorists are easier to detect thanks to technology developed at a National Lab and now installed in airports worldwide.

Improved grid resiliency 

A National Lab created an advanced battery that can store large amounts of energy from intermittent renewable sources — such as wind and solar — onto the power grid, while also smoothing over temporary disruptions to the grid. Several companies have licensed the technology and offer it as a commercial product.

Solved a diesel dilemma 

A National Lab insight into how catalysts behave paved the way for a new, “lean-burn” diesel engine that met emissions standards and improved fuel efficiency by 25 percent over conventional engines.

Harvested energy from air 

A miniature device — commercialized by private industry after a National Lab breakthrough — generates enough power from small temperature changes to power wireless sensors or radio frequency transmitters at remote sites, such as dams, bridges and pipelines.

Gone grid friendly 

Regulating the energy use of household appliances — especially at peak times — could slash energy demand and avoid blackouts. A National Lab appliance-control device senses grid stress and responds instantly to turn off machines and reduce end-use demand, balancing the system so that the power stays on.

Put the digital in DVDs 

The optical digital recording technology behind music, video and data storage originated at a National Lab nearly 40 years ago.

Locked nuclear waste in glass 

Disposal of U.S. Cold War waste is safer thanks to National Lab scientists who developed and deployed a process to lock it into glass to keep it from leaching into the environment.

Cleaned up anthrax 

Scientists at a National Lab developed a non-toxic foam that neutralizes chemical and biological agents. This foam was used to clean up congressional office buildings and mail rooms exposed to anthrax in 2001.

Removed radiation from Fukushima seawater 

After a tsunami damaged the Fukushima Daiichi nuclear power plant in 2011, massive amounts of seawater cooled the reactor. A molecular sieve engineered by National Lab scientists was used to extract radioactive cesium from tens of millions of gallons of seawater.11

Sped up Ebola detection 

In 2014, researchers from a National Lab modeled the Liberian blood sample transport system and made recommendations to diagnose patients quicker. This minimized the amount of time people were waiting together, reducing the spread of Ebola.

Prevented unauthorized use of a nuclear weapon 

In 1960, National Lab scientists invented coded electromechanical locks for all U.S. nuclear weapons. The switch blocks the arming signal until it receives the proper presidential authorization code.

Launched the LED lighting revolution 

In the 1990s, scientists at a National Lab saw the need for energy-efficient solid-state lighting and worked with industry to develop white LEDs. Today, white LEDs are about 30 percent efficient, with the potential to reach 70 percent to 80 percent efficiency. Fluorescent lighting is about 20 percent efficient and incandescent bulbs are 5 percent.

Mastered the art of artificial photosynthesis 

National Lab scientists engineered and synthesized multi-layer semiconductor structures in devices that directly convert sunlight to chemical energy in hydrogen by splitting water at efficiencies greater than 15 percent. This direct conversion of sunlight to fuels paves the way for use of solar energy in applications beyond the electrical grid.

Advanced fusion technology

From the first fusion test reactor to briefly produce power at the megawatt scale, and the world’s largest and most energetic laser creating extreme conditions mimicking the Big Bang, the interiors of planets and stars and thermonuclear weapons, to the international experiment to generate industrial levels of fusion energy from burning plasmas, fusion science and applications are advancing because of the National Labs.

Made the first molecular movie 

National Lab scientists have used ultrafast X-rays to capture the first molecular movies in quadrillionths-of-a-second frames. These movies detail the intricate structural dances of molecules as they undergo chemical reactions.

The National Laboratory System: Protecting America Through Science and Technology

For more than 75 years, the Department of Energy’s National Laboratories have solved important problems in science, energy and national security. This expertise keeps our nation at the forefront of science and technology in a rapidly changing world. Partnering with industry and academia, the laboratories also drive innovation to advance economic competitiveness and     ensure our nation’s future prosperity.

Oak Ridge National Laboratory – Demystifying Quantum Dot Conundrums – A ‘Titan’ Task at Lawrence Berkeley National Laboratory

Complete atomistic model of the colloidal lead sulfide nanoparticle, also known as a quantum dot, passivated with oleic acid, oleyl amine and hydroxyl ligands.

Berkeley researchers use Titan to seek solutions to decades-old nanocrystal mysteries

Since their discovery over two decades ago [ Rice – Smalley – Curly Institute – “Buckyballs” ] they have gone relatively unnoticed until recently. Now they are showing up in our TVs, smart phones, solar panels, and even our bodies. For something so small, we are beginning to see them everywhere.

Nanocrystals (NCs) are making a significant impact in materials sciences, resulting in better, more energy-efficient products, and in many cases at lower costs. This is because small is different; in other words, at nanoscale the relevant material properties and phenomena behave in interesting and useful ways—differently from how they behave at a scale, say, visible to the human eye.

The benefits of NC technologies are well known; however, on the atomic level, many of the characteristics and behaviors that make them so beneficial remain a mystery.

But thanks to the high-performance computing resources at the Oak Ridge Leadership Computing Facility (OLCF), they’re becoming less mysterious with the help of the Titan supercomputer, a Cray XK7 capable of 27 petaflops, or 27 quadrillion calculations per second. After completing a 3-year project, researchers from Lawrence Berkeley National Laboratory (LBNL) recently published two articles in the journal Science, revealing new insights into the NC atomic structure.

“Understanding more of the fundamental physics in different nanosystems, like how they grow, how the electrons behave, or how different molecules affect the system, allows us to utilize some control,” said lead investigator Lin-Wang Wang, a senior staff scientist at LBL. “And if we can control things like the crystal’s size and shape, we will be able to further advance their usefulness.”

The crystal soup concoction

When thinking about NCs, mind the scale—nanoscale is crazy small.

Picture a strand of hair: 1 nanometer is approximately 100,000 times smaller. Furthermore, each atom inside the crystals—arranged in a repeating, orderly 3D pattern—is 10 times smaller still. The structures Wang and his researchers deal with are typically about 5 nanometers, units with about 2,000 atoms each, called quantum dots (QDs).

It sounds intimidating, but surprisingly, synthesizing QDs is relatively simple; controlling their structure, however, is not.

“We call it a chemical cocktail,” Wang said. “Traditionally, laboratory experimentalists add ingredients like salt and acid [precursors] to organic solvents, or ‘soup,’ which, done under the right conditions, will cause the crystals to grow.”

Once that process is performed, within a matter of minutes a new crystal is formed. But saying “new crystal,” however, isn’t entirely accurate. NCs have the innate ability to regenerate. That is, if an NC is cut into smaller pieces, those smaller pieces will in fact grow back to their original shape during synthesis. Another way of describing it would be to say that once an NC reaches approximately 5 nanometers, growth in some cases abruptly stops.

But why do they do that? How do they do that? What’s happening on the NC surface that we can’t see? Are other molecules playing a role we don’t know about?

“At the atomic level, these were questions no one really had any answers to,” Wang said. “So the details of the atomic structure during passivation have for many, many years been like a black box.”

And according to him, a better understanding of what goes on during passivation is the key to opening that box.

“Imagine it like this,” said Danylo Zherebetskyy, a postdoctoral researcher in Wang’s group. “During passivation, organic molecules act like builders delivering bricks [atoms] to the particles’ surfaces. The molecules form extensions from the crystal’s center, almost like hairs that guide the atoms where to land, growing the crystal brick by brick.”

Those hairs are known as ligands, and not only are they responsible for growth, but they also influence how QDs interact with light, electrical charges, and other materials. And learning how to control ligand passivation, Zherebetskyy said, is critical in advancing nanotech applications.

Dissecting dots

Through an allocation from the OLCF’s Innovative and Novel Computational Impact on Theory and Experiment program, Wang and his team sought to answer those questions via a series of simulations, using Titan to calculate the surface energies and passivation patterns of lead sulfide and platinum nanocrystals.

Whereas laboratory experiments and various imaging methods could offer only hypotheses, for the first time Titan gave researchers precise predictions about NC surface development. Using the density functional theory codes VASP, LS3DF, and PEtot—quantum mechanics-based applications used to calculate the electronic and structural properties of molecules in many-body systems—researchers were able to develop an accurate, testable model, revealing an up-close examination of how each atom arranges itself within the system and how each of those molecules binds with other elements during passivation.

Because NC growth happens layer by layer, outward from the center, understanding the strange, abrupt stoppage in growth required the team to work from the outside in by slicing off sections of the NC surfaces. This process creates additional surfaces, each having different molecular arrangements and energies.

Wang explained: “For simplicity’s sake, let’s just look at two different surfaces. According to the old theory, based on principles in thermodynamics, the surface with the higher energy should grow the most because a higher energy means it’s more active, giving us an energetics picture. But what we find is just the opposite.”

As it turns out, the real secret to NC growth, Titan found, is ligand mobility.

“It takes a certain level of energy to displace a ligand on the surface, and that energy defines the ligand’s mobility,” Zherebetskyy said. “And the more energy it costs to displace the ligand, the more immobile it becomes.”

For growth to happen, he said, once a builder lays a brick, that ligand has to move out of the way so another atom can land next to it. Titan’s simulations made it clear, showing surfaces with lower energies facilitating the process, whereas higher energies actually create such a strong bond between the NC surface and the ligand molecules that passivation becomes completely blocked. Hence, NC growth abruptly stops.

“People have suspected this to be the case,” Wang said, “but until Titan, they never had the evidence to confirm that kinetic processes play a more important role than previously believed.”

The not-so-mysterious molecule

“I talk about size changing or controlling the properties, but the shape can also change the properties,” Wang said. “Different shapes will have different electronic structures and therefore will have different surfaces. Likewise, different surfaces require different methods of passivation.

“For almost 20 years we have been synthesizing inorganic [lead sulfide] quantum dots. But nevertheless, on the atomic level, no one has been able to figure out how the molecules attach to the particles’ surfaces.”

The reason, he explained, is that during passivation, a myriad of chemical reactions are taking place, making it impossible for physical testing or even advanced microscopy methods to identify every actor involved.

This was evidenced when the team placed a lead sulfide NC particle—recognized for its natural symmetry and its ability to form distinct facets—passivated with Oleic acid under Titan’s microscope to focus on unmasking unknown agents. By simulating the experiment, researchers can easily add or remove various molecules such as hydrogen and oxygen to observe their effects on passivation.

Consequently, because hydrogen and oxygen are two key ingredients of the Earth’s most valuable resource, it wasn’t entirely surprising when Titan revealed water to be the masked culprit behind the scenes of so many molecular mysteries. It was thought not possible because part of the synthesis process requires heating the precursor to 110°C (230°F), presumably eliminating any trace of water.

They found that water molecules occur as a byproduct of decomposition during crystal synthesis. Titan showed that water molecules, previously thought to exist only as a free-floating molecule within the soup, actually were a vital component in surface passivation.

“In the past, different experiments have revealed different features about surface passivation, from the amount of ligand molecules to the lead and sulfur atom ratios, but no one had ever put them together to agree with a single atomic model,” Wang said. “This is the first time all those observations actually fit.”

Truth be told

Titan’s findings subsequently aided the team in reproducing their experiments in the lab, giving them the physical confirmation needed to disprove several controversial theories.

The team produced large amounts of data by parallelizing their codes to take advantage of a significant number of Titan’s approximately 300,000 cores. Generated data sets were efficiently managed by routing them through the OLCF’s High Performance Storage System, a tape-based archiving tool.

“Without Titan our calculations would have taken forever, if not been outright impossible,” Zherebetskyy said.

“Our ability to simulate research has become a very powerful technique,” Wang added. “If you cannot do a simulation to get your result, then you probably still don’t fully understand your problem.”

Thanks to Titan and the many resources offered at the OLCF, a US Department of Energy Office of ScienceUser Facility, the team was able to combine computations with various methods of physical testing to produce groundbreaking results in the advancement of new nanomaterials studies.

“I think these projects are just the beginning,” Wang said. “We now have a complete model. So that, I think, will open the door for future investigations into the surface states for more realistic calculations for the QD.”

—Jeremy Rumsey

Oak Ridge National Laboratory is supported by the US Department of Energy’s Office of Science. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Berkeley Lab – DOE – Argonne – “Holy Grail” for Batteries: Solid-State Magnesium Battery a Big Step Closer

 

Berkeley Lab leads discovery of the fastest magnesium-ion solid-state conductor to date.

 

A team of Department of Energy (DOE) scientists at the Joint Center for Energy Storage Research (JCESR) has discovered the fastest magnesium-ion solid-state conductor, a major step towards making solid-state magnesium-ion batteries that are both energy dense and safe.

Argonne scientist Baris Key, shown on left at work in his nuclear magnetic resonance lab, worked with researchers at Berkeley Lab on the discovery of the fastest ever magnesium-ion solid-state conductor. (Credit: Argonne National Laboratory)

The electrolyte, which carries charge back and forth between the battery’s cathode and anode, is a liquid in all commercial batteries, which makes them potentially flammable, especially in lithium-ion batteries. A solid-state conductor, which has the potential to become an electrolyte, would be far more fire-resistant.

Researchers at DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Argonne National Laboratory were working on a magnesium battery, which offers higher energy density than lithium, but were stymied by the dearth of good options for a liquid electrolyte, most of which tend to be corrosive against other parts of the battery. “Magnesium is such a new technology, it doesn’t have any good liquid electrolytes,” said Gerbrand Ceder, a Berkeley Lab Senior Faculty Scientist. “We thought, why not leapfrog and make a solid-state electrolyte?”

The material they came up with, magnesium scandium selenide spinel, has magnesium mobility comparable to solid-state electrolytes for lithium batteries. Their findings were reported in Nature Communications in a paper titled, “High magnesium mobility in ternary spinel chalcogenides.”JCESR, a DOE Innovation Hub, sponsored the study, and the lead authors are Pieremanuele Canepa and Shou-Hang Bo, postdoctoral fellows at Berkeley Lab.

“With the help of a concerted effort bringing together computational materials science methodologies, synthesis, and a variety of characterization techniques, we have identified a new class of solid conductors that can transport magnesium ions at unprecedented speed,” Canepa said.

Collaboration with MIT and Argonne

The research team also included scientists at MIT, who provided computational resources, and Argonne, who provided key experimental confirmation of the magnesium scandium selenide spinel material to document its structure and function.

Co-author Baris Key, a research chemist at Argonne, conducted nuclear magnetic resonance (NMR) spectroscopy experiments. These tests were among the first steps to experimentally prove that magnesium ions could move through the material as rapidly as the theoretical studies had predicted.

“It was crucial to confirm the fast magnesium hopping experimentally. It is not often that the theory and the experiment agree closely with each other,” Key said. “The solid state NMR experiments for this chemistry were very challenging and would not be possible without dedicated resources and a funding source such as JCESR.

As we’ve shown in this study, an in-depth understanding of short- and long-range structure and ion dynamics will be the key for magnesium ion battery research.”

NMR is akin to magnetic resonance imaging (MRI), which is routinely used in medical settings, where it shows hydrogen atoms of water in human muscles, nerves, fatty tissue, and other biological substances. But researchers can also tune NMR frequency to detect other elements, including the lithium or magnesium ions that are found in battery materials.

The NMR data from the magnesium scandium selenide material, however, involved material of unknown structure with complex properties, making them challenging to interpret.

Canepa noted the challenges of testing materials that are so new. “Protocols are basically non-existent,” he said. “These findings were only possible by combining a multi-technique approach (solid-state NMR and synchrotron measurements at Argonne) in addition to conventional electrochemical characterization.”

Doing the impossible

The team plans to do further work to use the conductor in a battery. “This probably has a long way to go before you can make a battery out of it, but it’s the first demonstration you can make solid-state materials with really good magnesium mobility through it,” Ceder said. “Magnesium is thought to move slowly in most solids, so nobody thought this would be possible.”

Additionally, the research identified two related fundamental phenomena that could significantly affect the development of magnesium solid electrolytes in the near future, namely, the role of anti-site defects and the interplay of electronic and magnesium conductivity, both published recently in Chemistry of Materials.

Bo, now an assistant professor at Shanghai Jiao Tong University, said the discovery could have a dramatic effect on the energy landscape. “This work brought together a great team of scientists from various scientific disciplines, and took the first stab at the formidable challenge of building a solid-state magnesium battery,” he said. “Although currently in its infancy, this emerging technology may have a transformative impact on energy storage in the near future.”

Gopalakrishnan Sai Gautam, another co-author who was an affiliate at Berkeley Lab and is now at Princeton, said the team approach made possible by a DOE hub such as JCESR was critical. “The work shows the importance of using a variety of theoretical and experimental techniques in a highly collaborative environment to make important fundamental discoveries,” he said.

Ceder was excited at the prospects for the finding but cautioned that work remains to be done. “There are enormous efforts in industry to make a solid-state battery. It’s the holy grail because you would have the ultimate safe battery. But we still have work to do. This material shows a small amount of electron leakage, which has to be removed before it can be used in a battery.”

Funding for the project was provided by the DOE Office of Science through the Joint Center for Energy Storage Research, a Department of Energy Innovation Hub. The Advanced Photon Source, a DOE Office of Science User Facility at Argonne, added vital data to the study regarding the structure of the solid conductor.

The National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility at Berkeley Lab, provided computing resources. Other co-authors on the paper are Juchaun Li of Berkeley Lab, William Richards and Yan Wang of MIT, and Tan Shi and Yaosen Tian of UC Berkeley.

# # #

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel Prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state, and municipal agencies to help them solve their specific problems, advance America’s scientific leadership, and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

The Joint Center for Energy Storage Research (JCESR), a DOE Energy Innovation Hub, is a major partnership that integrates researchers from many disciplines to overcome critical scientific and technical barriers and create new breakthrough energy storage technology. Led by the U.S. Department of Energy’s Argonne National Laboratory, partners include national leaders in science and engineering from academia, the private sector, and national laboratories. Their combined expertise spans the full range of the technology-development pipeline from basic research to prototype development to product engineering to market delivery.

New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2

Brookhaven Lab chemists Ping Liu and José Rodriguez helped to characterize structural and mechanistic details of a new low-temperature catalyst for producing high-purity hydrogen gas from water and carbon monoxide.

Low-temperature “water gas shift” reaction produces high levels of pure hydrogen for potential applications, including fuel cells

UPTON, NY—Scientists have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO). The discovery—described in a paper set to publish online in the Journal Science — could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

“This catalyst produces a purer form of hydrogen to feed into the fuel cell,” said José Rodriguez, a chemist at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory. Rodriguez and colleagues in Brookhaven’s Chemistry Division—Ping Liu and Wenqian Xu—were among the team of scientists who helped to characterize the structural and mechanistic details of the catalyst, which was synthesized and tested by collaborators at Peking University in an effort led by Chemistry Professor Ding Ma.

“This catalyst produces a purer form of hydrogen to feed into fuel cells.”

— José Rodriguez

Because the catalyst operates at low temperature and low pressure to convert water (H₂O) and carbon monoxide (CO) to hydrogen gas (H₂) and carbon dioxide (CO₂), it could also lower the cost of running this so-called “water gas shift” reaction.

“With low temperature and pressure, the energy consumption will be lower and the experimental setup will be less expensive and easier to use in small settings, like fuel cells for cars,” Rodriguez said.

The gold-carbide connection

The catalyst consists of clusters of gold nanoparticles layered on a molybdenum-carbide substrate. This chemical combination is quite different from the oxide-based catalysts used to power the water gas shift reaction in large-scale industrial hydrogen production facilities.

“Carbides are more chemically reactive than oxides,” said Rodriguez, “and the gold-carbide interface has good properties for the water gas shift reaction; it interacts better with water than pure metals.”

Wenqian Xu and José Rodriguez of Brookhaven Lab and Siyu Yao, then a student at Peking University but now a postdoctoral research fellow at Brookhaven, conducted operando x-ray diffraction studies of the gold-molybdenum-carbide catalyst over a range of temperatures (423 Kelvin to 623K) at the National Synchrotron Light Source (NSLS) at Brookhaven Lab. The study revealed that at temperatures above 500K, molybdenum-carbide transforms to molybdenum oxide, with a reduction in catalytic activity.

 

“The group at Peking University discovered a new synthetic method, and that was a real breakthrough,” Rodriguez said. “They found a way to get a specific phase—or configuration of the atoms—that is highly active for this reaction.”

Brookhaven scientists played a key role in deciphering the reasons for the high catalytic activity of this configuration. Rodriguez, Wenqian Xu, and Siyu Yao (then a student at Peking University but now a postdoctoral research fellow at Brookhaven) conducted structural studies using x-ray diffraction at the National Synchrotron Light Source (NSLS) while the catalyst was operating under industrial or technical conditions. These operandoexperiments revealed crucial details about how the structure changed under different operating conditions, including at different temperatures.

With those structural details in hand, Zhijun Zuo, a visiting professor at Brookhaven from Taiyuan University of Technology, China, and Brookhaven chemist Ping Liu helped to develop models and a theoretical framework to explain why the catalyst works the way it does, using computational resources at Brookhaven’s Center for Functional Nanomaterials (CFN).

“We modeled different interfaces of gold and molybdenum carbide and studied the reaction mechanism to identify exactly where the reactions take place—the active sites where atoms are binding, and how bonds are breaking and reforming,” she said.

Additional studies at Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences (CNMS), the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory, and two synchrotron research facilities in China added to the scientists’ understanding.

“This is a multipart complex reaction,” said Liu, but she noted one essential factor: “The interaction between the gold and the carbide substrate is very important. Gold usually bonds things very weakly. With this synthesis method we get stronger adherence of gold to molybdenum carbide in a controlled way.”

That configuration stabilizes the key intermediate that forms as the reaction proceeds, and the stability of that intermediate determines the rate of hydrogen production, she said.

The Brookhaven team will continue to study this and other carbide catalysts with new capabilities at the National Synchrotron Light Source II (NSLS-II), a new facility that opened at Brookhaven Lab in 2014, replacing NSLS and producing x-rays that are 10,000 times brighter. With these brighter x-rays, the scientists hope to capture more details of the chemistry in action, including details of the intermediates that form throughout the reaction process to validate the theoretical predictions made in this study.

The work at Brookhaven Lab was funded by the U.S. DOE Office of Science.

Additional funders for the overall research project include: the National Basic Research Program of China, the Chinese Academy of Sciences, National Natural Science Foundation of China, Fundamental Research Funds for the Central Universities of China, and the U.S. National Science Foundation.

NSLS, NSLS-II, CFN, CNMS, and ALS are all DOE Office of Science User Facilities.

Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy.  The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time.  For more information, please visit science.energy.gov.

‘Magnesium Mystery’ for (Lithium-Based) Rechargeable Batteries Solved: DOE

Molecular models shows the initial state of battery chemistry that leads to instability in a test cell featuring a magnesium anode

Rechargeable batteries based on magnesium, rather than lithium, have the potential to extend electric vehicle range by packing more energy into smaller batteries. But unforeseen chemical roadblocks have slowed scientific progress.
And the places where solid meets liquid – where the oppositely charged battery electrodes interact with the surrounding chemical mixture known as the electrolyte – are the known problem spots.

Now, a research team at the U.S. Department of Energy’s Joint Center for Energy Storage Research, led by scientists at Lawrence Berkeley National Laboratory (Berkeley Lab), has discovered a surprising set of chemical reactions involving magnesium that degrade battery performance even before the battery can be charged up.

The findings could be relevant to other battery materials, and could steer the design of next-generation batteries toward workarounds that avoid these newly identified pitfalls.

The team used X-ray experiments, theoretical modeling, and supercomputer simulations to develop a full understanding of the chemical breakdown of a liquid electrolyte occurring within tens of nanometers of an electrode surface that degrades battery performance. Their findings are published online in the journal Chemistry of Materials (“Instability at the Electrode/Electrolyte Interface Induced by Hard Cation Chelation and Nucleophilic Attack”).

The battery they were testing featured magnesium metal as its negative electrode (the anode) in contact with an electrolyte composed of a liquid (a type of solvent known as diglyme) and a dissolved salt, Mg(TFSI)2.

While the combination of materials they used were believed to be compatible and nonreactive in the battery’s resting state, experiments at Berkeley Lab’s Advanced Light Source (ALS), an X-ray source called a synchrotron, uncovered that this is not the case and led the study in new directions.

These molecular models show the initial state of battery chemistry that leads to instability in a test cell featuring a magnesium (Mg) anode. (Credit: Berkeley Lab)

“People had thought the problems with these materials occurred during the battery’s charging, but instead the experiments indicated that there was already some activity,” said David Prendergast, who directs the Theory of Nanostructured Materials Facility at the Molecular Foundry and served as one of the study’s leaders.

“At that point it got very interesting,” he said. “What could possibly cause these reactions between substances that are supposed to be stable under these conditions?”

Molecular Foundry researchers developed detailed simulations of the point where the electrode and electrolyte meet, known as the interface, indicating that no spontaneous chemical reactions should occur under ideal conditions, either. The simulations, though, did not account for all of the chemical details.

“Prior to our investigations,” said Ethan Crumlin, an ALS scientist who coordinated the X-ray experiments and co-led the study with Prendergast, “there were suspicions about the behavior of these materials and possible connections to poor battery performance, but they hadn’t been confirmed in a working battery.”

Commercially popular lithium-ion batteries, which power many portable electronic devices (such as mobile phones, laptops, and power tools) and a growing fleet of electric vehicles, shuttle lithium ions – lithium atoms that become charged by shedding an electron – back and forth between the two battery electrodes. These electrode materials are porous at the atomic scale and are alternatively loaded up or emptied of lithium ions as the battery is charged or discharged.

In this type of battery, the negative electrode is typically composed of carbon, which has a more limited capacity for storing these lithium ions than other materials would.

So increasing the density of stored lithium by using another material would make for lighter, smaller, more powerful batteries. Using lithium metal in the electrode, for example, can pack in more lithium ions in the same space, though it is a highly reactive substance that burns when exposed to air, and requires further research on how to best package and protect it for long-term stability.

Magnesium metal has a higher energy density than lithium metal, meaning you can potentially store more energy in a battery of the same size if you use magnesium rather than lithium.

Magnesium is also more stable than lithium. Its surface forms a self-protecting “oxidized” layer as it reacts with moisture and oxygen in the air. But within a battery, this oxidized layer is believed to reduce efficiency and shorten battery life, so researchers are looking for ways to avoid its formation.

To explore the formation of this layer in more detail, the team employed a unique X-ray technique developed recently at the ALS, called APXPS (ambient pressure X-ray photoelectron spectroscopy). This new technique is sensitive to the chemistry occurring at the interface of a solid and liquid, which makes it an ideal tool to explore battery chemistry at the surface of the electrode, where it meets the liquid electrolyte.

Simulations show the weakening of a bond in a liquid solvent due to the presence of free-floating hydroxide ions, which contain a single oxygen atom bound to a hydrogen atom. In this illustration, atoms are color-coded: hydrogen (white), oxygen (red), carbon (light blue), magnesium (green), nitrogen (dark blue), sulfur (yellow), fluorine (brown). This process degrades battery performance. (Credit: Berkeley Lab)

Even before a current was fed into the test battery, the X-ray results showed signs of chemical decomposition of the electrolyte, specifically at the interface of the magnesium electrode. The findings forced researchers to rethink their molecular-scale picture of these materials and how they interact.

What they determined is that the self-stabilizing, thin oxide surface layer that forms on the magnesium has defects and impurities that drive unwanted reactions.

“It’s not the metal itself, or its oxides, that are a problem,” Prendergast said. “It’s the fact you can have imperfections in the oxidized surface. These little disparities become sites for reactions. It feeds itself in this way.”

A further round of simulations, which proposed possible defects in the oxidized magnesium surface, showed that defects in the oxidized surface layer of the anode can expose magnesium ions that then act as traps for the electrolyte’s molecules.

If free-floating hydroxide ions – molecules containing a single oxygen atom bound to a hydrogen atom that can be formed as trace amounts of water react with the magnesium metal – meet these surface-bound molecules, they will react.

This wastes electrolyte, drying out the battery over time. And the products of these reactions foul the anode’s surface, impairing the battery’s function.

It took several iterations back and forth, between the experimental and theoretical members of the team, to develop a model consistent with the X-ray measurements. The efforts were supported by millions of hours’ worth of computing power at the Lab’s National Energy Research Scientific Computing Center.

Researchers noted the importance of having access to X-ray techniques, nanoscale expertise, and computing resources at the same Lab.

The results could be relevant to other types of battery materials, too, including prototypes based on lithium or aluminum metal. Prendergast said, “This could be a more general phenomenon defining electrolyte stability.”

Crumlin added, “We’ve already started running new simulations that could show us how to modify the electrolyte to reduce the instability of these reactions.” Likewise, he said, it may be possible to tailor the surface of the magnesium to reduce or eliminate some of the unwanted chemical reactivity.

“Rather than allowing it to create its own interface, you could construct it yourself to control and stabilize the interface chemistry,” he added. “Right now it leads to uncontrollable events.”

Source: By Glenn Roberts Jr., Lawrence Berkeley National Laboratory

 

 

Solar-to-Fuel System Recycles CO2 to Make Ethanol and Ethylene: Berkeley National Lab

Schematic of a solar-powered electrolysis cell which converts carbon dioxide into hydrocarbon and oxygenate products with an efficiency far higher than natural photosynthesis. Power-matching electronics allow the system to operate over a range of sun conditions. (Credit: Clarissa Towle/Berkeley Lab)

Berkeley Lab advance is first demonstration of efficient, light-powered production of fuel via artificial photosynthesis

Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have harnessed the power of photosynthesis to convert carbon dioxide into fuels and alcohols at efficiencies far greater than plants. The achievement marks a significant milestone in the effort to move toward sustainable sources of fuel.

Many systems have successfully reduced carbon dioxide to chemical and fuel precursors, such as carbon monoxide or a mix of carbon monoxide and hydrogen known as syngas. This new work, described in a study published in the journal Energy and Environmental Science, is the first to successfully demonstrate the approach of going from carbon dioxide directly to target products, namely ethanol and ethylene, at energy conversion efficiencies rivaling natural counterparts.

The researchers did this by optimizing each component of a photovoltaic-electrochemical system to reduce voltage loss, and creating new materials when existing ones did not suffice.

“This is an exciting development,” said study principal investigator Joel Ager, a Berkeley Lab scientist with joint appointments in the Materials Sciences and the Chemical Sciences divisions. “As rising atmospheric CO2 levels change Earth’s climate, the need to develop sustainable sources of power has become increasingly urgent. Our work here shows that we have a plausible path to making fuels directly from sunlight.”

That sun-to-fuel path is among the key goals of the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub established in 2010 to advance solar fuel research. The study was conducted at JCAP’s Berkeley Lab campus.

The initial focus of JCAP research was tackling the efficient splitting of water in the photosynthesis process. Having largely achieved that task using several types of devices, JCAP scientists doing solar-driven carbon dioxide reduction began setting their sights on achieving efficiencies similar to those demonstrated for water splitting, considered by many to be the next big challenge in artificial photosynthesis.

Another research group at Berkeley Lab is tackling this challenge by focusing on a specific component in a photovoltaic-electrochemical system. In a study published today, they describe a new catalyst that can achieve carbon dioxide to multicarbon conversion using record-low inputs of energy.

Not just for noon

For this JCAP study, researchers engineered a complete system to work at different times of day, not just at a light energy level of 1-sun illumination, which is equivalent to the peak of brightness at high noon on a sunny day. They varied the brightness of the light source to show that the system remained efficient even in low light conditions.

When the researchers coupled the electrodes to silicon photovoltaic cells, they achieved solar conversion efficiencies of 3 to 4 percent for 0.35 to 1-sun illumination. Changing the configuration to a high-performance, tandem solar cell connected in tandem yielded a conversion efficiency to hydrocarbons and oxygenates exceeding 5 percent at 1-sun illumination.

Copper-Silver Cathode

At left is a surface view of a bimetallic copper-silver nanocoral cathode taken from a scanning electron micrograph. To the right is an energy-dispersive X-ray image of the cathode with the copper (in pink/red) and silver (in green) highlighted. (Credit: Gurudayal/Berkeley Lab)

“We did a little dance in the lab when we reached 5 percent,” said Ager, who also holds an appointment as an adjunct professor at UC Berkeley’s Materials Science and Engineering Department.

Among the new components developed by the researchers are a copper-silver nanocoral cathode, which reduces the carbon dioxide to hydrocarbons and oxygenates, and an iridium oxide nanotube anode, which oxidizes the water and creates oxygen.

“The nice feature of the nanocoral is that, like plants, it can make the target products over a wide range of conditions, and it is very stable,” said Ager.

The researchers characterized the materials at the National Center for Electron Microscopy at the Molecular Foundry, a DOE Office of Science User Facility at Berkeley Lab. The results helped them understand how the metals functioned in the bimetallic cathode. Specifically, they learned that silver aids in the reduction of carbon dioxide to carbon monoxide, while the copper picks up from there to reduce carbon monoxide further to hydrocarbons and alcohols.

Seeking better, low-energy breakups

Because carbon dioxide is a stubbornly stable molecule, breaking it up typically involves a significant input of energy.
“Reducing CO2 to a hydrocarbon end product like ethanol or ethylene can take up to 5 volts, start to finish,” said study lead author Gurudayal, postdoctoral fellow at Berkeley Lab. “Our system reduced that by half while maintaining the selectivity of products.”

Notably, the electrodes operated well in water, a neutral pH environment.

“Research groups working on anodes mostly do so using alkaline conditions since anodes typically require a high pH environment, which is not ideal for the solubility of CO2,” said Gurudayal. “It is very difficult to find an anode that works in neutral conditions.”

The researchers customized the anode by growing the iridium oxide nanotubes on a zinc oxide surface to create a more uniform surface area to better support chemical reactions.

“By working through each step so carefully, these researchers demonstrated a level of performance and efficiency that people did not think was possible at this point,” said Berkeley Lab chemist Frances Houle, JCAP deputy director for Science and Research Integration, who was not part of the study. “This is a big step forward in the design of devices for efficient CO2 reduction and testing of new materials, and it provides a clear framework for the future advancement of fully integrated solar-driven CO2-reduction devices.”

Other co-authors on the study include James Bullock, a Berkeley Lab postdoctoral researcher in materials sciences, who was instrumental in engineering the system’s photovoltaic and electrolysis cell pairing. Bullock works in the lab of study co-author Ali Javey, Berkeley Lab senior faculty scientist and a UC Berkeley professor of electrical engineering and computer sciences.

This work is supported by the DOE Office of Science.

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel Prizes. 
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