Category: Advanced Light Source (ALS)

Keeping Water-Treatment Membranes from Fouling Out

Keeping Water-Treatment Membranes from Fouling Out

When you use a membrane for water treatment, junk builds up on the membrane surface—a process called fouling—which makes the treatment less efficient. In this work, researchers studied how membranes are fouled by interactions between natural organic matter and positively charged ions (such as calcium cations) that are commonly found in water from dissolved minerals and salts.

“Fouling has been studied since membranes emerged for use in water purification decades ago, but it still remains one of the largest challenges in water treatment,” said the study’s first author, Matthew Landsman, an ALS collaborative postdoctoral fellow from the University of Texas at Austin’s Center for Materials for Water and Energy Systems (M-WET), a DOE Energy Frontier Research Center (EFRC). “Our research aimed to understand the molecular-level mechanisms that influence membrane fouling by natural organic matter so that we can establish design rules for making better membranes.”

After running laboratory fouling experiments on membranes at UT Austin, the team used synchrotron characterization techniques at the Advanced Light Source (ALS) and Brookhaven’s National Synchrotron Light Source II (NSLS-II) to analyze the surface and bulk compositions of the fouled membranes. At ALS Beamline 7.3.3, wide angle x-ray scattering (WAXS) was used to see if any inorganic contaminants, such as calcium carbonate, were precipitating on the membranes. At NSLS-II, soft and tender x-ray scattering experiments determined the distribution of calcium in the fouling layers.

Read more on the BNL website

Image: Top: Water-treatment facilities use arrays of cylindrical elements containing rolled-up membranes to filter contaminants from water. Bottom inset: In this experiment, such membranes were used to filter water containing ions (reddish spheres) and natural organic matter (green-brown blobs). The fouled membranes were analyzed using various x-ray probes, revealing (for example) how calcium cations form bridges between organic molecules, causing them to aggregate and reduce flow through the membrane.

Vestiges of the Early Solar System in Ryugu Asteroid

Vestiges of the Early Solar System in Ryugu Asteroid

Samples returned to Earth from the asteroid Ryugu, analyzed in part at the Advanced Light Source (ALS), revealed that the building blocks of life formed 4.6 billions years ago in the extreme cold of space, followed by reaction with water.

The dark, coal-like organic matter in the carbonaceous asteroid could have contributed to the formation of habitable planetary environments.

In 2014, the Japan Aerospace Exploration Agency (JAXA) launched the Hayabusa2 spacecraft. Its mission: to collect and return samples from the near-Earth asteroid, Ryugu. Asteroids are excellent time capsules, preserving material sourced from the early solar system in pristine condition. With such samples, scientists aim to learn more about how extraterrestrial organic compounds were formed and modified, and whether this material could have eventually seeded life on Earth. Although meteorites can provide valuable information along these lines, they are subject to terrestrial weathering and other contamination from a planet teeming with life.

Hayabusa2 returned to Earth in 2020 to drop off a capsule containing about 5 grams of extraterrestrial material. The spacecraft then left Earth orbit for an extended mission to a smaller asteroid, called 1998 KY26. The samples it left behind were carefully curated and distributed to teams around the world for study.

In the portion of the sample analysis described here, an international team of 130 researchers, led by Hikaru Yabuta at Hiroshima University, received a share of the irreplaceable Ryugu particles for studies of their organic (carbon-based) content. They examined intact Ryugu grains and insoluble carbonaceous residues isolated by acid treatment.

At ALS Beamline 5.3.2.2, the researchers used scanning transmission x-ray microscopy (STXM) to identify discrete grains of organic material (about 200 nm in size) for further examination by x-ray absorption near-edge structure (XANES) spectroscopy. The beamline enables the acquisition of elemental maps and functional group compositions in submicron-sized sample areas with a spatial resolution below 30 nm.

Read more on the ALS website

Image: Artwork showing the Hayabusa2 spacecraft retrieving a sample from the surface of asteroid Ryugu

Credit: Akihiro Ikeshita

Dimitri Argyriou Named Next Director of Berkeley Lab’s Advanced Light Source

Dimitri Argyriou Named Next Director of Berkeley Lab’s Advanced Light Source

Dimitri Argyriou, an accomplished physicist and Associate Director for In-Kind Management at the European Spallation Source, has been selected to serve as the next director of the Advanced Light Source (ALS) at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). His appointment is expected to begin this June. The announcement follows an international search.

“I am very pleased that Dimitri is joining us to become the next director of the Advanced Light Source,” said Berkeley Lab Director Mike Witherell. “With his expertise and leadership experience at some of the world’s leading research laboratories, he is well suited to ensure the ALS and its community will continue to advance science for the benefit of society.”

The ALS is an X-ray synchrotron scientific user facility that produces extremely bright X-ray, infrared, and extreme ultraviolet light for more than 1,800 visiting scientists each year. Up to 40 experiments can be performed simultaneously using the synchrotron, resulting in nearly 900 peer-reviewed scientific articles each year across a range of fields, from chemistry and materials sciences to biology and environmental sciences.

In addition, the ALS is undergoing a major upgrade, called ALS-U, which will take advantage of state-of-the-art technologies to endow the ALS with light more than 100 times brighter than the facility offers today, opening the door to new realms of scientific study and keeping the ALS’s world-leading capabilities.

Read more on the ALS website

Image: Dimitri Argyriou

Credit: European Spallation Source

How a record-breaking copper catalyst converts CO2 into liquid fuels

How a record-breaking copper catalyst converts CO2 into liquid fuels

Researchers at Berkeley Lab, collaborating with CHESS scientists at the PIPOXS beamline, have made the first real-time movies of copper nanoparticles as they evolve to convert carbon dioxide and water into renewable fuels and chemicals. Their new insights could help advance the next generation of solar fuels.

Since the 1970s, scientists have known that copper has a special ability to recycle carbon dioxide into valuable chemicals and fuels. But for many years, scientists have struggled to understand how this common metal works as an electrocatalyst, a mechanism that uses energy from electrons to chemically transform molecules into different products.

Now, a research team led by Lawrence Berkeley National Laboratory (Berkeley Lab) has gained new insight by capturing the world’s first real-time movies of copper nanoparticles (copper particles engineered at the scale of a billionth of a meter) as they convert CO2 and water into renewable fuels and chemicals: ethylene, ethanol, and propanol, among others. The work was reported in the journal Nature.

“This is very exciting. After decades of work, we’re finally able to show – with undeniable proof – how copper electrocatalysts excel in CO2 reduction,” said Peidong Yang, a senior faculty scientist in Berkeley Lab’s Materials Sciences and Chemical Sciences Divisions who led the study. Yang is also a professor of chemistry and materials science and engineering at UC Berkeley. “Knowing why copper is such an excellent electrocatalyst brings us steps closer to turning CO2 into new, renewable solar fuels through artificial photosynthesis.”

Read more on the CHESS website

Image: Artist’s rendering of a copper nanoparticle as it evolves during CO2 electrolysis: Copper nanoparticles (left) combine into larger metallic copper “nanograins” (right) within seconds of the electrochemical reaction, reducing CO2 into new multicarbon products.

Credit: Yao Yang/Berkeley Lab

First direct measurement of elusive Donnan potential

First direct measurement of elusive Donnan potential

Scientific achievement

At the Advanced Light Source (ALS), researchers performed the first direct measurement of the Donnan electrical potential, which arises from an imbalance of charges at membrane-solution interfaces.

Significance and impact

Considered unmeasurable for over a century, the Donnan potential is relevant to a wide range of fields, from cell biology to energy storage and water desalination.

A breakthrough with great potential

The Donnan electrical potential arises from an imbalance of charges at the interface of a charged membrane and a liquid, and for more than a century it stubbornly eluded direct measurement. Many researchers had even written off such a measurement as impossible. Now, using ambient-pressure x-ray photoelectrion spectroscopy (APXPS) at the ALS, scientists directly measured the Donnan potential for the first time.

The ability to probe the characteristics of this potential at membrane-solution interfaces could yield new insights in biology, energy science, and materials science. For example, the Donnan potential plays a critical role in biological functions ranging from muscle contractions to neural signaling. Energy storage and water purification using ion exchange membranes (IEMs) are also important applications involving the Donnan potential.

Read more on the ALS website

Image: Left: Schematic of the x-ray experiment. Right: The presence of fixed ions inside a membrane generates an electrochemical potential gradient (the Donnan potential) that leads to more counter-ions (with charge opposite that of the fixed ions) diffusing from the solution to the membrane relative to co-ions (which have the same charge as the fixed ions).

Advanced Light Source upgrade approved to start construction

Advanced Light Source upgrade approved to start construction

Berkeley Lab’s biggest project in three decades now moves from planning to execution. The ALS upgrade will make brighter beams for research into new materials, chemical reactions, and biological processes.

The Advanced Light Source (ALS), a scientific user facility at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), has received federal approval to start construction on an upgrade that will boost the brightness of its X-ray beams at least a hundredfold.

“The ALS upgrade is an amazing engineering undertaking that is going to give us an even more powerful scientific tool,” said Berkeley Lab Director Michael Witherell. “I can’t wait to see the many ways researchers use it to improve the world and tackle some of the biggest challenges facing society today.”

Scientists will use the upgraded ALS for research spanning biology; chemistry; physics; and materials, energy, and environmental sciences. The brighter, more laser-like light will help experts better understand what’s happening at extremely small scales as reactions and processes take place. These insights can have a huge array of applications, such as improving batteries and clean energy technologies, creating new materials for sensors and computing, and investigating biological matter to develop better medicines.

“That’s the wonderful thing about the ALS: The applications are so broad and the impact is so profound,” said Dave Robin, the project director for the ALS upgrade. “What really excites me every day is knowing that, when it’s complete, the ALS upgrade will enable researchers to make scientific advances in many different areas for the next 30 to 40 years.”

The DOE approval, known as Critical Decision 3 (CD-3), formally releases funds for purchasing, building, and installing upgrades to the ALS. This includes constructing an entirely new storage ring and accumulator ring, building four feature (two new and two upgraded) beamlines, and installing seismic and shielding upgrades for the concrete structure housing the equipment. The $590 million project is the biggest investment at Berkeley Lab since the ALS was built in 1993.

Read more on the Berkeley Laboratory website

Image: The upgrade to the Advanced Light Source at Berkeley Lab will add two new particle accelerator rings within the iconic building’s footprint. 

Credit: Thor Swift/Berkeley Lab

Watching nanoparticle chemistry and structure evolve

Watching nanoparticle chemistry and structure evolve

Using a multimodal approach developed at the Advanced Light Source (ALS), researchers learned how chemical properties correlate with structural changes during nanoparticle growth.

The work will enable a greater understanding of the mechanisms affecting the durability of nanoparticles used to catalyze a broad range of chemical reactions, including clean-energy reactions.

Catalyzing technological progress

In applications ranging from chemical synthesis to energy storage, catalysts enable chemical reactions to run at more favorable temperatures, pressures, or in general, with lower energy requirements. For example, catalysts enable the efficient splitting of water to generate hydrogen, which can then be used as a clean, decarbonized fuel.

For such applications, nanoparticles on the surface of a transition-metal oxide work well as catalysts, but they are susceptible to coarsening, agglomeration, and other forms of degradation, shortening their usable lifetime. In this work, researchers applied a technique they developed at the ALS to simultaneously study the chemistry and structure of catalyst materials as they form, a capability that will help scientists identify strategies for improving nanoparticle durability.

Understanding nanoparticle exsolution

A process called “exsolution” has shown significant promise for controlling nanoparticle size, shape, distribution, and stability. Briefly, the process involves causing dopant atoms in a host matrix to migrate to the surface and gather to form nanoparticles. This is done by heating the host material under reducing conditions (i.e., in a reducing gas such as hydrogen). Exsolution from metal oxide hosts produces highly stable metal nanoparticles that are often partially embedded in the oxide surface and show high activity for the oxygen evolution reaction (OER), a key step in many electrochemical reactions, including water splitting.

Here, the samples studied were thin films of SrTi0.9Nb0.05Ni0.05O3-δ (STNNi). When STNNi is heated in H2 gas, the Ni atoms migrate to the surface and form nanoparticles. Before the reducing treatment, such samples are inactive with respect to the OER. After treatment, the system becomes active, despite a relatively small amount of Ni doping.

Read more on the ALS website

Image: Atomic force microscope images of nickel- and niobium-co-doped strontium titanate, before (left) and after (right) thermal treatment in a reducing (H2) atmosphere. After treatment, bright features consistent with the formation of nickel nanoparticles are observed.

#SynchroLightAt75 – From the Ribosome to CRISPR

#SynchroLightAt75 – From the Ribosome to CRISPR

Structural Biology at the ALS: From the Ribosome to CRISPR

Since the first protein crystallography beamline came online here in 1997, thousands of protein structures have been solved at the Advanced Light Source (ALS). One of the earliest high-profile structures was that of the full ribosome complex, where all the proteins necessary for life are produced based on RNA blueprints. The results reinforced the impression that the ribosome is a dynamic molecular machine with moving parts and a very complicated mechanism of action. More recently, the ALS has contributed to a greater understanding of programmable CRISPR proteins such as Cas9. In contrast to earlier genome-editing tools, Cas9 transforms the complicated and expensive process of gene editing into something simpler and more routine, like applying a genetic plug-in. In 2020, Jennifer Doudna and Emmanuelle Charpentier were awarded the Nobel Prize in Chemistry for “the development of a method for genome editing.”

Read more in the links below:

Publications:

J.H. Cate et al., Science 285, 2095 (1999)

M. Jinek et al., Science 343, 1247997 (2014)

Press release: The Nobel Prize in Chemistry 2020

ALS highlights:

Solving the Ribosome Puzzle
Intriguing DNA Editor (CAS9) Has a Structural Trigger

Jennifer Doudna and the Nobel Prize: The Advanced Light Source Perspective

Multilayer stack opens door to low-power electronics

Multilayer stack opens door to low-power electronics

Researchers found that a stack of ultrathin materials, characterized in part at the Advanced Light Source (ALS), exhibits a phenomenon called negative capacitance, which reduces the voltage required for transistor operation.

The material is fully compatible with today’s silicon-based technology and is capable of reducing power consumption without sacrificing transistor size or performance.

High efficiency, low disruption

Microelectronics is expected to account for about 5% of total electricity production by 2030 thanks to ever-increasing demands for information processing. Maintaining progress will require a fundamental shift toward more efficient devices, with an emphasis on materials compatible with state-of-the-art silicon technology.

The phenomenon of negative capacitance represents one possible solution, promising to significantly reduce power consumption in electronic devices while fitting seamlessly into current semiconductor protocols. In this work, researchers took a key step toward integrating negative capacitance into advanced transistors, with support from various government and industrial groups including Samsung, Intel, SK hynix, Applied Materials, and DARPA.

Inside the gate

A transistor is essentially an on-off switch for the flow of current through a semiconductor, activated by a small voltage from a “gate” electrode. A thin insulating layer (the gate oxide) separates the semiconductor from the gate. Increasing the gate oxide’s ability to store charge (i.e., its capacitance) lowers the transistor’s operating voltage and thus reduces overall power consumption.

In advanced silicon transistors, the gate oxide is a combination of silicon oxide (SiO2) and hafnium oxide (HfO2). In this work, researchers replaced the HfO2 with a multilayered stack that displays negative capacitance—a counterintuitive effect in which decreasing the gate voltage increases the stored charge on the gate oxide, thus maintaining performance at reduced power.

Read more on the Berkeley Laboratory website

Image: Artistic rendering of a multilayered structure that exhibits negative capacitance, integrated onto a silicon chip. Incorporating this material into advanced silicon transistors could make devices more energy efficient.

Credit: Ella Maru Studio/UC Berkeley

A new leap in understanding nickel oxide superconductors

A new leap in understanding nickel oxide superconductors

Researchers discover they contain a phase of quantum matter, known as charge density waves, that’s common in other unconventional superconductors. In other ways, though, they’re surprisingly unique.

BY GLENNDA CHUI

A new study shows that nickel oxide superconductors, which conduct electricity with no loss at higher temperatures than conventional superconductors do, contain a type of quantum matter called charge density waves, or CDWs, that can accompany superconductivity.

The presence of CDWs shows that these recently discovered materials, also known as nickelates, are capable of forming correlated states – “electron soups” that can host a variety of quantum phases, including superconductivity, researchers from the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University reported in Nature Physics today.

“Unlike in any other superconductor we know about, CDWs appear even before we dope the material by replacing some atoms with others to change the number of electrons that are free to move around,” said Wei-Sheng Lee, a SLAC lead scientist and  investigator with the Stanford Institute for Materials and Energy Science (SIMES) who led the study.

“This makes the nickelates a very interesting new system – a new playground for studying unconventional superconductors.”

Nickelates and cuprates

In the 35 years since the first unconventional “high-temperature” superconductors were discovered, researchers have been racing to find one that could carry electricity with no loss at close to room temperature. This would be a revolutionary development, allowing things like perfectly efficient power lines, maglev trains and a host of other futuristic, energy-saving technologies.

But while a vigorous global research effort has pinned down many aspects of their nature and behavior, people still don’t know exactly how these materials become superconducting.

So the discovery of nickelate’s superconducting powers by SIMES investigators three years ago was exciting because it gave scientists a fresh perspective on the problem. 

Since then, SIMES researchers have explored the nickelates’ electronic structure – basically the way their electrons behave – and magnetic behavior. These studies turned up important similarities and subtle differences between nickelates and the copper oxides or cuprates – the first high-temperature superconductors ever discovered and still the world record holders for high-temperature operation at everyday pressures.

Since nickel and copper sit right next to each other on the periodic table of the elements, scientists were not surprised to see a kinship there, and in fact had suspected that nickelates might make good superconductors. But it turned out to be extraordinarily difficult to construct materials with just the right characteristics.

“This is still very new,” Lee said. “People are still struggling to synthesize thin films of these materials and understand how different conditions can affect the underlying microscopic mechanisms related to superconductivity.”

Read more on the SLAC website

Image: An illustration shows a type of quantum matter called charge density waves, or CDWs, superimposed on the atomic structure of a nickel oxide superconductor. (Bottom) The nickel oxide material, with nickel atoms in orange and oxygen atoms in red. (Top left) CDWs appear as a pattern of frozen electron ripples, with a higher density of electrons in the peaks of the ripples and a lower density of electrons in the troughs. (Top right) This area depicts another quantum state, superconductivity, which can also emerge in the nickel oxide. The presence of CDWs shows that nickel oxides are capable of forming correlated states – “electron soups” that can host a variety of quantum phases, including superconductivity.

Credit: Greg Stewart/SLAC National Accelerator Laboratory

Copper doping improves sodium-ion battery performance

Copper doping improves sodium-ion battery performance

Although lithium-ion batteries currently drive the electronic world, sodium-ion batteries are gaining ground. A big plus is that sodium is more earth-abundant than lithium, which lowers costs and eases environmental and supply-chain concerns. As a result, enormous research efforts are underway to improve the energy density and cycling longevity of sodium-ion batteries.

One promising strategy to enhance energy density is to exploit additional sources of a key chemical reaction—oxidation reduction (redox)—in the battery’s cathode. In cathodes made of layered transition-metal oxides (the sodium ions move in and out from between the layers), it turns out that the oxygen component in the layers unexpectedly contributes to redox activity. Unfortunately, oxygen redox is frequently accompanied by irreversible oxygen behavior, resulting in both voltage and capacity decays.

To enhance oxygen redox reversibility, researchers doped a sodium-ion cathode material (Na0.6Mg0.3Mn0.7O2, or NMMO) with copper ions (Na0.6Mg0.15Mn0.7Cu0.15O2, or NMMCO). To understand how this affects the oxygen redox activity, they used a technique developed at Beamline 8.0.1 of the Advanced Light Source (ALS), called mapping of resonant inelastic x-ray scattering (mRIXS), to measure the effect of the copper doping at different states of charge.

“The mRIXS technique is one of the most powerful characterization tools available for detecting oxygen redox activities in battery electrodes,” said Liang Zhang, a professor at Soochow University and co-corresponding author of the published work. “With mRIXS, it’s also possible to quantify the reversibility of the oxygen redox reaction, which could greatly help us understand the oxygen evolution process during electrochemical cycling.”

Read more on the ALS website

Image: The partial substitution of Mg ions in the cathode with Cu ions, which possess similar ionic radii but distinct electronic states, led to strong Cu–O bonds (i.e., modulated transition metal (TM)–O covalency), which helped stabilize the lattice during repeated cycles. Light blue = Cu, dark green = Na, red = O, dark yellow = Mn, blue = Mg

Safely studying dangerous infections just got a lot easier

Safely studying dangerous infections just got a lot easier

An extremely fast new 3D imaging method can show how cells respond to infection and to possible treatments

To combat a pandemic, science needs to move quickly. With safe and effective vaccines now widely available and a handful of promising COVID-19 treatments coming soon, there’s no doubt that many aspects of biological research have been successfully accelerated in the past two years.

Now, researchers from Lawrence Berkeley National Laboratory (Berkeley Lab) and Heidelberg University in Germany have cranked up the speed of imaging infected cells using soft X-ray tomography, a microscopic imaging technique that can generate incredibly detailed, three-dimensional scans.

Their approach takes mere minutes to gather data that would require weeks of prep and analysis with other methods, giving scientists an easy way to quickly examine how our cells’ internal machinery responds to SARS-CoV-2, or other pathogens, as well as how the cells respond to drugs designed to treat the infection.

“Prior to our imaging technique, if one wanted to know what was going on inside a cell, and to learn what changes had occurred upon an infection, they’d have to go through the process of fixing, slicing, and staining the cells in order to analyze them by electron microscopy. With all the steps involved, it would take weeks to get the answer. We can do it in a day,” said project co-lead Carolyn Larabell, a Berkeley Lab faculty scientist in the Biosciences Area. “So, it really speeds up the process of examining cells, the consequences to infection, and the consequences of treating a patient with a drug that may or may not cure or prevent the disease.”

Taking cellular freeze frames

Larabell is a professor of anatomy at UC San Francisco and director of the National Center for X-Ray Tomography, a facility based at Berkeley Lab’s Advanced Light Source (ALS). The facility’s staff developed soft X-ray tomography (SXT) in the early 2000s to fill in the gaps left by other cellular imaging techniques. They currently offer the SXT to investigators worldwide and continue to refine the approach. As part of a study published in Cell Reports Methods late last year, she and three colleagues performed SXT on human lung cell samples prepared by their colleagues at Heidelberg University and the German Center for Infection Research.

Read more on the Berkeley Lab website

Image: Digital images of cells infected with SARS-CoV-2, created from soft X-ray tomography taken of chemically fixed cells at the Advanced Light Source

Credit: Loconte et al./Berkeley Lab

Metal-Organic Frameworks can capture toxic air pollutants

Metal-Organic Frameworks can capture toxic air pollutants

The air that we breathe

According to the World Health Organisation1 (WHO), 92% of people worldwide live in places with poor air quality, and outdoor air pollution causes 4.2 million deaths a year, with another 3.8 million caused by indoor air pollution.

Figures published by Public Health England2 showed that the health and social care costs of air pollution in England alone were £42.88 million in 2017 and could reach £5.3 billion by 2035.

There are many different types of air pollution, which arise from a wide range of sources. In the UK, five types are of particular concern: 

  1. The mixture of liquid droplets and solid particles found in the air is called particulate matter (PM). Some PM comes from natural sources (e.g., pollen, sea spray and desert dust), but it also includes dust from car exhausts, brakes and tyres and smoke. PM is classified according to size, with PM2.5 (particles less than 2.5 micrometres across) able to reach and damage the lungs and other organs.
  2. Volatile organic compounds (VOCs) are a range of organic molecules that display similar behaviour in the atmosphere. These include vapours from household products such as air fresheners, cleaning products and perfumes, as well as petrol and solvents.
  3. Ammonia (NH3) gas is mainly released from agricultural sources such as slurry, other rotting farm waste and fertilisers.
  4. Nitrogen oxide (NOx) gases, including nitrogen dioxide (NO2), are mainly created by burning fossil fuels. 
  5. Sulphur dioxide (SO2) is an acidic gas that can irritate airways, particularly in people with asthma.

SO2 and NO2 are both reactive, corrosive gases. Removing them from the air is challenging but would have enormous benefits for human health. 

Can we clean up our act with MOFs?

Metal-Organic Frameworks (MOFs) are sponge-like materials that can adsorb and hold “guest” molecules. By fine-tuning their properties – pore size and geometry, framework topology and chemical functionality – they can be tailored for specific applications, including gas adsorption, separation, catalysis, substrate binding and delivery. MOFs containing open metal sites (OMSs), in particular, can provide highly selective adsorption of target gases. 

However, stable MOFs with OMSs are rare, as are MOF materials that can reversibly adsorb SO2 and NO2. While there are already over 100,000 known MOFs (and over half a million structures have so far been predicted), screening each one individually for its suitability for this application would be time-consuming and costly. A far better approach is to improve our understanding of the mechanism of active sites within capture materials so that we can design or discover new functional MOF materials. This in itself is a challenging task, as host-guest interactions are often dynamic processes, where multiple binding sites of similar energies affect the movement of guest molecules in the pores.

Using synchrotron techniques, an international team of researchers has described the synthesis, crystal structure and gas adsorption and separation properties of a unique {Ni12}- wheel-based MOF that exhibits high isothermal uptake of SO2 and NO2.

Using single crystal X-ray diffraction (SCXRD) at the Advanced Light Source in California and infrared (IR) single crystal micro-spectroscopy at Diamond’s B22 beamline, the team performed dynamic breakthrough experiments that confirmed the selective retention of SO2 and NO2 at low concentrations under dry conditions. Their results show, at a crystallographic resolution, a detailed molecular mechanism with reversible coordination of SO2 and NO2 at the six open Ni(II) sites on the {Ni12}-wheel and at oxygen atom and ligand sites. 

Read more on the Diamond website

Image: Artist’s impression of the unique {Ni12}- wheel-based MOF in action, exhibiting high isothermal uptake of SO2 and NO2.


Credit: Dr Sihai Yang

More to life than light

More to life than light

The #LightSourceSelfies video campaign highlights the dedication and enthusiasm that is felt by those working in this field. To maintain a sense of physical and mental wellbeing, it is also important to make time for non-work related things like family, hobbies and interests. This montage, with contributors from the ESRF, ALS, MAX IV and Diamond, gives a flavour of the wide range of activities that those in the light source community enjoy when they are not working.

Nights!

Nights!

Experimental time at light sources is very precious. When a synchrotron or X-ray Free Electron Laser (XFEL) is in operating mode the goal is to allocate as many experimental shifts to external scientists and in-house research as possible. This includes night shifts! So, how do light source users survive the night shifts? #LightSourceSelfies brings you top tips from scientists based at, or using, 5 light sources in our collaboration – the ESRF, Advanced Light Source (ALS), ANSTO’s Australian Synchrotron, CHESS and the PAL XFEL.