X-ray nanotomography reveals 3D microstructure of graphite anodes for lithium-ion batteries

The optimisation of battery electrode architecture is a key aspect of improving battery performance, provided that precise characterisation of the complex battery microstructure is possible. In this work, X-ray nanotomography [1] was used at beamline ID16B [2] to obtain high-resolution images of the microstructure of graphite battery electrodes, providing 3D analysis and thorough quantification of the electrode/particle inner structure and porosity at the nanoscale.

A crucial step in the production of battery-grade natural graphite for lithium-ion batteries is the spheroidisation process: the morphological change that occurs in the electrode material during cycling or charging/discharging cycles. However, the low yield (30-50%) of this process results in a large quantity of wasted graphite fines that are not suitable for use in lithium-ion batteries due to their small particle size [3]. A method was devised to recycle waste graphite fines via a re-agglomeration process followed by a petroleum pitch coating in order to obtain aggregated graphite particles with sound mechanical strength and battery-suitable size to be used for electrode preparation. A compression step called ‘calendering’ was applied to the electrode’s coating to reduce its thickness and consequently increase its volumetric capacity.

X-ray nanotomography measurements carried out at beamline ID16B provided important microstructural details of the electrode-representative volumes (128 × 128 × 108 µm3 with 50 nm voxel size), along with statistical analysis of ~500 particles imaged in a single measurement. Data acquired on non-calendered and calendered pristine electrodes show that higher electrode density could be reached by calendering the electrode, without considerably affecting the active material accessibility through diffusion in the pore network. Despite the considerable morphological changes, no clear agglomerate fractures were observed, and particle integrity was preserved as individual agglomerate particles could still be distinguished. This highlights the fact that structural integrity is maintained from the electrode scale down to the particle level, and that the calendering process does not compromise the electrochemical performance.

Read more on ESRF website

Image: lectrode and particle porosity evolution with calendering in terms of (a) pore volume fraction and (b-e) microstructure. 3D rendering views of the (b) non-calendered and (c) calendered electrodes and (d,e) corresponding isolated graphite aggregated particles (with cross-section images).

Cement hydration in 4D: towards a reduction in emissions

Researchers led by the University of Málaga show the Portland cement early age hydration with microscopic detail and high contrast between the components. This knowledge may contribute to more environmentally friendly cements. The results are now published in Nature Communications.

Concrete is a fluid mass that strikingly sets and hardens in hours, even under water. This fabricated rock, which is made of cement, water, sand and gravel, is the basic building block of our civilization. Hence, it is not a surprise that it is the world’s largest manufactured commodity. The enormous production of Portland cement (PC), at 4 billion tonnes per year, results in 2.7 billion tonnes of CO2 emissions per year. If cement production were considered a country, it would be the third CO2 emitter in the world, just after China and USA. Therefore, reducing the CO2 footprint of cement, mortar and concrete is a societal need.

The main drawback of the current proposals for low-carbon cements is the slow hydration kinetics in the first 3 days. “Understanding the processes related to cement hydration as it takes place at its early stages is crucial”, explains Shiva Shirani, first author of the paper and PhD student at the University of Malaga. Despite a century of research, our understanding of cement dissolution and precipitation processes at early ages is very limited. “So we have developed a methodology to get a full picture of the hydration of Portland cement”, she adds.

The team, which is led by the University of Málaga and includes the ESRF, the Paul Scherrer Institute PSI (Switzerland) and the University Grenoble Alpes (France), carried out a tomographic study in the laboratory for an initial characterisation, followed by phase-contrast microtomography experiments with synchrotron radiation to take data very quickly and in large sample volumes, and finally experiments at the nanometric scale, using synchrotron ptychotomography.

Read more on the ESRF website

Image: Scientists followed the hydration process of cement in its early stages

Credit: Shiva Shirani

X-ray diffraction reveals ancient Egyptian illustration methods

The ancient Egyptians used papyrus as a medium for communication and illustration, with the first illustrations appearing in the fifth and sixth dynasties (2500 – 2100 B.C.). Funerary documents, such as the Book of the Dead, flourished during the New Kingdom period as they were considered essential for entering the afterlife.

The Champollion Museum in Vif, France, holds a collection of 280 papyrus fragments, many of which show scenes from the Book of the Dead. The colours used in these illustrations are typical of the Egyptian palette and include blue, green, red, pink, yellow and white, with different characters and elements of the illustrations outlined with a black line.

Researchers from the ESRF and the Néel Institute CNRS/UGA in Grenoble, France, with collaborators from the Champollion Museum, worked together to gain a deeper understanding of the illustration processs used in ancient Egypt. A combination of optical microscopy, synchrotron X-ray powder diffraction, X-ray fluorescence and Raman spectroscopy was used to identify the pigments and their overall distribution.

Two of the papyrus fragments of the collection (PAP-6 and PAP-12) were examined on beamline ID22, where X-ray fluorescence and X-ray diffraction experiments were carried out. Mixed Rietveld and Pawley refinement was carried out against the XRD data to quantify the fine fraction and to consider the heterogeneous microstructure of the pigments.

Read more on the ESRF website 

Environmental pollutants found incrusted in iron in endometriotic lesions

Scientists led by Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS), the Italian Research Hospital Burlo Garofolo in Trieste show that iron presence in endometriosis is associated to the accumulation of environmental metals, supporting the idea that the environment exposure to toxic chemicals plays a role in the disease.

Around 1 in 10 women in reproductive age around the world live with endometriosis, an inflammatory disease caused when tissue similar to the lining of the uterus grows outside the womb, such as in the ovaries and fallopian tubes. This causes pain and, in many cases, infertility. Even if women have always been affected by endometriosis, it is only since recently that the scientific community has started looking into it. 

The factors that may lead to endometriosis go from genetic predisposition to autoimmune diseases and environmental triggers. Now a team from Institute for Maternal and Child health IRCCS Burlo Garofolo in Trieste (Italy) has found the presence of iron clustered with environmental metals, such as lead, aluminium or titanium, using beamlines ID21 and id16B at the ESRF.

The accumulation of iron in endometriosis was already well documented. Iron deposits are common in endometrial lesions, indicating an altered iron metabolism. “We knew that iron can create oxidative stress and hence, inflammation, as it does in other conditions, such as asbestosis, so we wanted to know more about what chemical form it takes, how it is distributed and whether there are other environmental pollutants with it”, explains Lorella Pascolo, leader of the study. 

Pascolo and her team came to the ESRF to compare iron nanoaggregates in endometrial lesions of patients with normal endometrium samples of the same patients. “The ESRF beamlines are exceptional instruments to get a clear picture of the role of iron and how it transforms into endometrial lesions”, explains Pascolo. 

They used X-ray fluorescence (XRF) on beamline ID21 to track the presence and distribution of iron and environmental pollutants, and ID16B to fine-tune the findings and reveal additional heavy metals at the nano level. They also used X-ray spectroscopy to reveal the chemical state of the iron. 

Read more on the ESRF website

Unusual compound found in Rembrandt’s The Night Watch

An international team of scientists from the Rijksmuseum, the CNRS, the ESRF the European Synchrotron, the University of Amsterdam and the University of Antwerp, have discovered a rare lead compound (named lead formate) in Rembrandt’s masterpiece The Night Watch. This discovery, which is a first in the history of the scientific study of paintings, provides new insight into 17th-century painting technique and the conservation history of the masterpiece. The study is published in Angewandte Chemie – International edition.

The Night Watch, painted in 1642 and displayed today in the Rijksmuseum Amsterdam (The Netherlands), is one of Rembrandt’s most important masterpieces and largest work of art. In the framework of the 2019 Operation Night Watch, the largest research and conservation project ever undertaken for Rembrandt’s masterpiece, an international research team joined forces to study how the painting materials react chemically and with time.

The team of scientists combined multi-scale imaging methods in order to chemically study the materials used by Rembrandt in The Night Watch. A X-ray scanning instrument developed at the University of Antwerp (Belgium) was applied directly to the painting, while tiny fragments taken from the painting were studied with synchrotron micro X-ray probes, at the ESRF, the European Synchrotron (France), and PETRA-III facility (Germany). These two types of analyses revealed the presence of an unexpected organo-metallic compound: lead formates. This compound had never been detected before in historic paintings: “In paintings, lead formates have only been reported once in 2020, but in model paintings (mock-up, fresh paints). And there lies the surprise: not only do we discover lead formates, but we identify them in areas where there is no lead pigment, white, yellow. We think that probably they disappear fast, this is why they were not detected in old master paintings until now”, explains Victor Gonzalez, CNRS researcher at the Supramolecular and Macromolecular Photophysics and Photochemistry (PPSM) laboratory (CNRS/ENS Paris-Saclay) and first author of the paper.

Read more on the ESRF website

Image: The Night Watch, Rembrandt van Rijn, 1642

Credit: Rijskmuseum Amsterdam

Scientists find the presence of fluids derived from subducted slab in the lower mantle

A team of scientists, led by University College Cork (Ireland) and Bayreuth Geoinstitute (Germany), has found proof of subducted slab fluids in the lower mantle by studying inclusions in diamonds using the ESRF.

In the Juína region, in the west of Brazil, a volcanic eruption brought diamonds from the interior of the Earth to the surface around 93 millions of years ago. Diamonds form perfect capsules so they retain the exact chemistry of material from the part of the Earth where they formed. Scientists are therefore studying these minerals to get information on the composition of the deep upper mantle, the transition zone and lower mantle.

Now a team led by University College Cork (Ireland) and Bayreuth Geoinstitute (Germany) has found that subducted material has penetrated into the sublithosperic mantle (below 250 km) by testing the oxidation state of several diamonds from the Juína region using the ESRF.

The oxidation state of the Earth’s mantle controls important parameters and processes, such as magma generation, speciation and mobility of fluids and melts in the Earth’s interior, deep carbon cycle, recycling of oceanic crust back into the mantle, chemical differentiation of the planet and many others.

It is generally considered that the main three layers of the Earth – its crust, mantle and core, represent profound changes in the oxidation state of iron from ferric (Fe3+) at the surface to mostly Fe2+ in the silicate minerals in the upper mantle, transition zone and the lower mantle and ultimately, to the Fe0 in the core. In short, the surface is very oxidised and the core is metallic so it is very reduced.

Read more on the ESRF website

Image: Georgios Aprilis, ESRF postdoc at ID18 beamline

Long COVID and pulmonary fibrosis better understood thanks to innovative techniques

An international team of researchers has revealed how scarring occurs in Long-COVID and pulmonary fibrosis using innovative blood biomarkers and X-ray technology. This study, published in The Lancet – eBioMedicine, contributes to the knowledge on the pathophysiology of severe COVID-19 and thus its treatment.

Long-COVID syndrome, or the origin of the long-term consequences of SARS-CoV-2 infection, is still not fully understood, more than two years after the onset of the pandemic. In particular, the long-term changes in lung tissue following severe COVID-19 disease pose significant limitations for many patients. Some of these patients continue to develop post-COVID pulmonary fibrosis, which is characterised by rapid scarring of the lung tissue.

Until now, the scientific community didn’t understand the underlying mechanisms of this scarring and of specific blood markers that can predict this process. Now, an international research team led by doctors and researchers at the Institute of Pathology at the RWTH Aachen University Hospital, the Hannover Medical School (MHH), HELIOS University Hospital in Wuppertal, and the University Medical Center Mainz, in collaboration with scientists at University College London (UCL) and the European Synchrotron (ESRF), has uncovered the mechanism that modifies the connective tissue of the lung in severe COVID-19. By combining the latest in imaging and molecular biology techniques this multidisciplinary team uncovered a mechanism by which the connective tissue of the lung is modified in severe COVID-19. They have demonstrated how COVID-19 changes the structure of the finest blood vessels in the lung and found molecular markers of this damage in the blood of patients that might ultimately help diagnose and treat the condition.

Read more on the ESRF website

Image: Two of the co-authors, Claire Walsh and Paul Tafforeau, during the scans and experiments at the ESRF, the European Synchrotron.

The history of one of the oldest objects in the Solar system unveiled

An international team of scientists have unveiled details of the history of the asteroid Ryugu, a truly ancient object in the Solar system, after the Hayabusa2 mission brought samples from this asteroid back to Earth. The ESRF was one of the institutes involved in sample characterization, on ID15A. The results are published in Science.

The asteroid Ryugu, located at 200 million kilometres from the Earth, is one of the most primitive objects of the solar system. The Japanese spacecraft Hayabusa2 explored it from 2018 until it came back to Earth two years later with minuscule multiple samples from the asteroid.

Two years later, and thanks to the international collaboration of institutes led by the Japan Aerospace Exploration Agency (JAXA), the first results on the analysis of the samples shed light on the history of Ryugu, from its formation to its collisional destruction.

Researchers used cosmochemical and physical methods at universities and institutes, including the ESRF and four other synchrotron radiation facilities in Japan, United States, and Europe.

The results combined with computer simulation have allowed scientists to picture the origins of Ryugu:  the Ryugu parent body accumulated about 2 million years after the formation of the solar system, and then heated up to about 50°C over the next 3 million years, resulting in chemical reactions between water and rock. The size of the impactor that destroyed the Ryugu parent body, which is about 100 km in diameter, is at most 10 km in diameter, and that the present-day Ryugu is composed of material from a region far from the impact point.

What the data explain

In particular, the seventeen Ryugu samples analysed contain particles (such as Ca- and Al-rich inclusions) that were formed in high-temperature environments (>1000°C). These high-temperature particles are thought to have formed near the Sun and then migrated to the outer solar system, where Ryugu was formed. This indicates that large-scale mixing of materials occurred between the inner and outer solar system at the time of its birth.

Based on the detection of the magnetic field left in the Ryugu samples, it is highly likely that the original asteroid from which the current Ryugu descended (Ryugu’s parent body) was born in the darkness of nebular gas, far from the Sun, where sunlight cannot reach.

The scientists also discovered liquid water trapped in a crystal in a sample. This water was carbonated water containing salts and organic matter, which was once present in the Ryugu parent body. Crystals shaped as coral reefs grew from the liquid water that existed inside Ryugu’s parent body. Rocks that were deeper underground contained more water than those in the surface.

Read more on the ESRF website

Image: A coloured view of the C-type asteroid 162173 Ryugu, seen by the ONC-T camera on board of Hayabusa2.

Credit: JAXA Hayabusa 2

New insight into how mammal ancestors became warm-blooded

The shapes of the ear canals of mammal ancestors reveal when warm-bloodedness evolved. The study published in Nature demonstrates that mammal ancestors became warm-blooded later than previously thought – nearly 20 million years later-, and that the acquisition of endothermy seems to have occurred very quickly in geological terms, in less than a million years. The international team of scientists, led by London’s Natural History Museum, the University of Lisbon’s Instituto Superior Técnico, the Field Museum in Chicago, and including the University of Witwatersrand, used the ESRF bright X-rays to scan delicate and dense fossils.

Read more on the ESRF website

Image: Comparison of bony labyrinth shape in two examples of warm-blooded (left) and cold-blooded (right) prehistoric mammal ancestors. © Romain David and Ricardo Araújo.

Antibody rigidity regulates immune activity

Scientists at the University of Southampton have gained unprecedented new insight into the key properties of an antibody needed to stimulate immune activity to fight off cancer, using the ESRF’s structural biology beamlines, among others.

The interdisciplinary study, published in Science Immunology, revealed how changing the flexibility of the antibody could stimulate a stronger immune response. The findings have enabled the team to design antibodies to activate important receptors on immune cells to “fire them up” and deliver more powerful anti-cancer effects. The researchers believe their findings could pave the way to improve antibody drugs that target cancer, as well as automimmune diseases.

In the study, the team investigated antibody drugs targeting the receptor CD40 for cancer treatment. Clinical development has been hampered by a lack of understanding of how to stimulate the receptors to the right level. The problem being that if antibodies are too active they can become toxic. Previous research by the same team had shown that a specific type of antibody called IgG2 is uniquely suited as a template for pharmaceutical intervention, since it is more active than other antibody types. However, the reason why it is more active had not been determined. What was known, however, is that the structure between the antibody arms, the so called hinges, changes over time.

This latest research harnesses this property of the hinge and explains how it works: the researchers call this process “disulfide-switching”. In their study, the team analysed the effect of modifying the hinge and used a combination of biological activity assays, structural biology, and computational chemistry to study how disulfide switching alters antibody structure and activity.

Read more on the ESRF website

Image: Flexibility of the monoclonal antibody F(ab) arms is conferred by the hinge region disulphide structure

Credit: C. Orr

It sucked to be the prey of ancient cephalopods

The Jurassic cephalopod Vampyronassa rhodanica, thought to be the oldest known ancestor of the modern-day vampire squid (Vampyroteuthis infernalis), was likely an active hunter – a mode of life that is in contrast with its opportunistic descendant. Scientists led by Sorbonne University came to this conclusion after analysing microtomographic data of this rare fossil, acquired at the ESRF and the Muséum national d’Histoire naturelle in Paris. The results are published today in Scientific Reports.

Vampyronassa rhodanica is thought to be one of the oldest relatives of the modern-day vampire squid (Vampyroteuthis infernalis), which is the only remaining living species of its family. This modern form lives in extreme deep ocean environments, often with little oxygen, and feeds on drifting organic matter. Like V. infernalis, the body of V. rhodanica was mostly made of soft tissue. As this rarely fossilises, little is known about the physical characteristics and evolutionary history of this family.

Despite the scarcity of fossil material from this family, Alison Rowe, from Sorbonne University and colleagues were able to study 3 well-preserved V. rhodanica specimens from La Voulte-sur-Rhône (Ardèche, France), dating to more than 164 million years ago. The eight-armed specimens were small, measuring around 10 cm in length, and had elongated oval-shaped bodies with two small fins.

They took them to the ESRF for non-destructive 3-D imaging: “We used synchrotron tomography at the ESRF in order to better identify the outlines of the various anatomical features”, says Rowe. However, the task was challenging, as Vincent Fernández, scientist at the ESRF, explains: “The fossils are on small slabs, which are very difficult to scan. On top of that, soft tissues are preserved but we needed phase contrast imaging to visualise the faint density variation in the data. The coherence of beamline ID19 was therefore very important to perform propagation phase-contrast computed-tomography and track all the minute details, such as the suckers and small fleshy extensions, called cirri”. 

Read more on the ESRF website

Image: Hypothesised reconstruction of Vampyronassa rhodanica

Credit: A. Lethiers, CR2P-SU

Scientists synthesise new materials at terapascal pressures for the first time

A team led by the University of Bayreuth (Germany) has synthesized, for the first time, new materials at terapascal pressures, using the ESRF’s ID11 and a unique diamond anvil cell. The results are published in the journal Nature.

Matter changes with variations of pressure and temperature, which allows the tuning of many material properties. These possibilities can shed light onto scientific questions, such as the fundamental understanding of the Universe or lead to targeted design of advanced materials. For example, today super-abrasive cubic Boron Nitride is used for grinding high-quality tool steels and artificial diamonds created using high temperature and high pressure are more prevalent than natural ones.

A team of scientists led by the University of Bayreuth has synthesized new materials at terapascal pressures using laser heating for the first time. The team used rhenium-nitrogen compounds as models to show that studies at pressures three times higher than pressure in the center of the Earth are now possible. Natalia Dubrovinskaya, professor at the University of Bayreuth and one of the corresponding authors of the paper, explains the relevance of these compounds:  “These novel rhenium-nitrogen compounds showed that at ultra-high pressures we can make materials that cannot be made at lower pressures/temperatures, and uncover fundamental rules of physics and chemistry. We found, for example, that due to a huge compression, rhenium behaves chemically in a similar way to iron”.

Read more on the ESRF website

Image: Schematic illustration of the Diamond Anvil Cell assembly

Credit: Timofey Fedotenko

What drives rechargeable battery decay?

How quickly a battery electrode decays depends on properties of individual particles in the battery – at first. Later on, the network of particles matters more.

Rechargeable lithium-ion batteries don’t last forever – after enough cycles of charging and recharging, they’ll eventually go kaput, so researchers are constantly looking for ways to squeeze a little more life out of their battery designs.

Now, researchers at the Department of Energy’s SLAC National Accelerator Laboratory and colleagues from Purdue University, Virginia Tech, and the European Synchrotron Radiation Facility have discovered that the factors behind battery decay actually change over time. Early on, decay seems to be driven by the properties of individual electrode particles, but after several dozen charging cycles, it’s how those particles are put together that matters more.

“The fundamental building blocks are these particles that make up the battery electrode, but when you zoom out, these particles interact with each other,” said SLAC scientist Yijin Liu, a researcher at the lab’s Stanford Synchrotron Radiation Lightsource and a senior author on the new paper. Therefore, “if you want to build a better battery, you need to look at how to put the particles together.”

Read more on the SLAC website

Image: A piece of battery cathode after 10 charging cycles. A machine-learning feature detection and quantification algorithm allowed researchers to automatically single out the most severely damaged particles of interest, which are highlighted in the image.

Credit: Courtesy Yijin Liu/SLAC National Accelerator Laboratory

Everyone remembers their 1st day at a light source

Light sources around the world share a common quality. They all have the ability to deliver a ‘wow factor’ when people first step inside. From young, bright eyed, tech-savvy children; scientists embarking on their first experiments; right through to retired visitors who spent their younger years without telephones or TVs. Synchrotron and X-ray Free Electron Lasers (XFELs) deliver science and technology on a grand scale. In this #LightSourceSelfie, Ida, a Phd Student at the ESRF, and Michael, who undertakes experiments at the European XFEL, both recall their first day. The words they use include exciting, overwhelming, exhilarating, busy and fascinating. Michael remembers feeling slightly in the way but, at a certain point, he started to ask questions. From that first day he learnt to, “Always ask questions. You can’t ask enough questions!”

The reign of the dinosaurs ended in spring

The asteroid that killed nearly all dinosaurs struck Earth during springtime.  An international team of scientists from the Vrije Universiteit (VU) Amsterdam (The Netherlands), Uppsala University (Sweden), Vrije Universiteit Brussel (Belgium) and the ESRF, the European Synchrotron (France), have determined when the meteorite crashed onto the Earth, after analysing the remains of fish that died just after the impact. Their results are published in the journal Nature today.

Around 66 million years ago, the Chicxulub meteorite crashed into the Earth, in what today is the Yucatán peninsula in Mexico, marking the demise of dinosaurs and end of the Cretaceous period. This mass extinction still puzzles scientists today, as it was one of the most selective in the history of life: all non-avian dinosaurs, pterosaurs, ammonites, and most marine reptiles disappeared, whilst mammals, birds, crocodiles, and turtles survived.

A team of scientists from the Vrije Universiteit, Uppsala University, and the ESRF have now shed light on the circumstances surrounding the diverse extinction across the different groups. The answers came from the bones of fish that died moments after the meteorite struck.

Read more on the ESRF website

Image: Melanie During points to a section of a Paddlefish dentary showing high bone cell density (i.e. summer)

Credit: Melanie During