Brazilian Synchrotron Light Laboratory (LNLS)

Ptychographic computed X-ray tomography reveals structure of porous membranes on the nano scale

2023/11/162023/11/21

Article published in Communications Materials presents significant findings and discusses the possibilities offered by this technique combined with synchrotron light sources

Porous materials play key roles in a variety of contexts, from transporting water and nutrients in biological systems to storing oil and water in reservoirs of rock. And synthetic polymer membranes are essential to separation processes, as in the case of chromatography. They have well-established applications in water desalination, hemodialysis, and gas separation, and these uses are expanding into processes that filter out pollutants from contaminated water. Their benefits include energy efficiency, smaller carbon footprint, and compact design that provides a large area of membrane in a small volume.

Membranes that can fulfill technological objectives have complex porous structures that ensure the required selectivity, mechanical stability, and characteristics for rapid transport; the effectiveness and performance of these membranes is defined by characteristics such as porosity and interconnectivity, which can be particularly difficult to measure when they are brought down to the nano scale.

The limitations of electron microscopy and advantages of ptychographic X-ray computed tomography

Techniques such as scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM) have helped scientists better understand the transport mechanisms in these applications and develop membranes for different purposes. But even though they are powerful, these techniques also have significant limitations: the samples must be dehydrated and covered with a metallic layer, and must also remain in a vacuum during analysis, which can affect the structure of these membranes and hinder analysis under near-real conditions.

Furthermore, when the pores of the material reach the nano scale, the total sample volume must be significantly reduced in order to attain the resolution necessary for analysis. Within this context, X-ray tomography has emerged as a good alternative. This method not only offers non-destructive visualization, but samples can be analyzed in ambient conditions with significantly larger total sample volumes.

Conventional X-ray tomography, which analyzes different absorption in different parts of a sample, faces challenges related to resolution limits when analyzing less dense materials (such as membranes). But as new fourth-generation synchrotron light sources have recently come online and ptychographic X-ray tomography has been developed, images of these materials can be obtained with nanometric resolution.

Ptychographic X-ray computed tomography (PXCT) is a powerful phase-contrast imaging technique that uses a series of two-dimensional projections of the object from different angles to reconstruct its three-dimensional structure in high resolution, revealing information about porosities and interconnectivity.

Read more on CNPEM website

Sirius helps reveal previously unknown process of maturation for key protein in SARS-CoV-2 replication

2023/04/262023/06/06

Researchers at USP in São Carlos combined cutting-edge technologies and demonstrated that a molecule targeted by medications behaves differently than previously theorized.

A group of researchers from the University of São Paulo in São Carlos has just presented their findings from research indicating a new understanding of the maturation process and how inhibitors act upon the Mpro protein, an essential component in the life cycle of the Sars-CoV-2 virus and the target of various efforts to develop medications to treat Covid-19. Their results appear in an article entitled “An in-solution snapshot of SARS-COV-2 main protease maturation process and inhibition,” published in the journal Nature Communications (https://doi.org/10.1038/s41467-023-37035-5).

Mpro is an abbreviation for main protease, because of its importance to the virus. Today, two medications are available which interact with this molecule to treat covid-19. Still, some of the processes in this protein’s activity are not yet entirely understood, and this was the object of the study undertaken at Sirius.

As part of the role it plays in the life cycle of the Sars-CoV-2 virus, Mpro undergoes a series of modifications until it reaches its final form. Part of this process had already been described by the group from São Carlos, directed by Professor Glaucius Oliva.

André Godoy, who led the group, was one of the first external users of Sirius, the cutting- synchrotron light source planned and built by the Brazilian Center for Research in Energy and Materials (CNPEM), an organization overseen by the Ministry of Science, Technology and Innovation (MCTI).

In September 2020 he brought approximately 200 crystals containing proteins from the Sars-CoV-2 virus for analysis in the Manacá beamline, which was developed for experiments involving X-ray diffraction crystallography. “The Manacá beamline was the first research station to open at Sirius, as the result of a task-force effort at the CNPEM to support research exploring molecular mechanisms related to covid-19. This is one of the publications that resulted from this effort,” explains Harry Westfahl, Director of the Brazilian Synchrotron Light National Laboratory (LNLS).

Read more on the LNLS website

Image: Cryomicroscopy map of the Mpro dimer interacting with the N-terminal. Image obtained from analyses conducted at Diamond and Sirius by the USP São Carlos group

New biocatalyst could more efficiently split water molecules

2023/02/242023/03/03

Experiment carried out on Sirius shed light on reaction fundamental to the production of hydrogen fuel

A recent experiment at Sirius, the Brazilian synchrotron light source at the Brazilian Center for Research in Energy and Materials (CNPEM) in Campinas, São Paulo (see Pesquisa FAPESP issue 269) showed how a certain biological catalyst can more efficiently split water molecules (H₂O) using electrolysis. This reaction, an electrochemical process that uses electricity to break down water into the elements that comprise it, is very significant because it produces not only oxygen but also hydrogen, considered the fuel of the future by many specialists because it does not emit any polluting gases when it is utilized (see Pesquisa FAPESP issue 314).

“We discovered that when some enzymes present in nature like bilirubin oxidase (BOD) are manipulated in the lab, they can accelerate the reaction to split water,” states chemist Frank Nelson Crespilho, a professor at the University of São Paulo’s São Carlos Institute of Chemistry (IQSC-USP) who led the study. “We didn’t know why this happened; thanks to new equipment developed specifically for Sirius, we were able to observe how this enzyme, BOD, behaves during the process of oxidation in water. We found that the copper atoms within it are relevant to this reaction.”

Crespilho expects this advance to pave the way for science to get inspiration from the part of the enzyme that accelerated the reaction. “It is important for us to recognize the important regions of BOD, since today synthetic chemists that work in materials production can copy and synthesize this part of the enzyme in the laboratory. This will make the catalyst much more affordable, with a much broader range of potential applications,” he adds. Most of the catalysts used in this process utilize noble metals like platinum and iridium, making large-scale application unfeasible due to the cost involved. An article describing the experiment written by Crespilho’s team, which includes the researchers Graziela Sedenho, Rafael Colombo, Thiago Bertaglia, and Jessica Pacheco, was published in October in the journal Advanced Energy Materials. Scientists from the Brazilian Synchrotron Light National Laboratory (LNLS) also participated in the study.

Read more on the LNLS website

Image: Researcher manipulates electrochemical cell used in experiment

Researchers investigate the origins of superconductivity

2022/10/262022/11/11

The first scientific paper published with data obtained at the EMA beamline studied the relationship between skutterudite’s superconducting properties and the distance between their atoms.

In Brazil, about 7.5% of the electricity produced is lost in transmission and distribution. This happens because the materials that make up these systems are not perfect electrical conductors and dissipate part of the energy, for example, in the form of heat. Similarly, even though electric cars are much more efficient than combustion-engine vehicles, they can still lose up to 15 percent of their energy during the charging process.

Thus, the challenges of achieving sustainable development lie not only in the availability of abundant, clean, and cheap energy, but also in the development of new, efficient, and low-cost energy transport and storage systems.

In turn, these new systems require research into new materials with special properties, such as superconducting materials. Superconductivity is the property that allows certain materials to conduct electric current without resistance and therefore without energy loss. Currently, however, a major limitation for the large-scale use of superconducting materials is their need to be kept at very low temperatures, close to absolute zero (-273.15°C), which requires their association with large cooling infrastructures. In these conditions, superconductors have applications in MRI machines and other high-performance medical equipment, as well as in scientific research equipment, such as the super-magnets used in particle accelerators.

Although superconductivity has been known for more than a century, its origin is still a matter of intense debate in the scientific community. Why do certain materials exhibit superconductivity while others do not? Once this is known, it will be possible to build materials that are superconducting even under ambient temperature and pressure conditions, allowing a true technological revolution, not only in the transmission and storage of energy but also in all kinds of electrical equipment in everyday life.

The movement of electrons without resistance along a superconducting material is understood so far to be possible by the union of two electrons (called Cooper pairs) that, with the help of a deformation in the material’s lattice (called a phonon), can overcome Coulombian repulsion and start moving as a single particle.

The question to which there is still no satisfactory answer is: what makes these electrons want to come together in pairs? Among the various hypotheses, one possibility is that this phenomenon would be connected to the distance between the atoms in the superconducting material.

Thus, in research published in the journal Materials, researchers from the Brazilian Center for Research in Energy and Materials (CNPEM), and collaborators from Germany, investigated two materials (LaPt₄Ge₁₂ and PrPt₄Ge₁₂) whose crystalline structure is known as skutterudite to test the hypothesis that superconductivity would be related to the distance between the atoms of the material. This was the first scientific paper published with data obtained at the EMA beamline of CNPEM’s synchrotron light source Sirius.

Read more on the LNLS website

Capybara gut holds valuable enzymes for biotechnology

2022/04/132022/06/23

Study elucidates unprecedented processes of herbivore metabolism involved in the efficient degradation of plant fibers

A group of researchers from the Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), an organization supervised by the Brazilian Ministry of Science, Technology and Innovations (MCTI), has published in the journal Nature Communications a study that explores some of the most modern resources of current science to reveal unprecedented and valuable details of the capybara’s digestive process.

The capybara, the largest rodent on the planet, is known for its ability to degrade very efficiently the biomass it consumes, but the details of the animal’s microbiota metabolism that contribute to this characteristic have not yet been elucidated. Researcher Mario Murakami recalls that, in Brazil, this animal is used to eating sugarcane. “Since Brazilian biodiversity is an invaluable source of biotechnological solutions, our hypothesis was that the microorganisms inhabiting capybaras’ intestines have, throughout evolution, developed highly effective molecular strategies for the degradation and use of this biomass of great industrial and economic importance. And that was demonstrated in our study.”

“Population and molecular inventory” of the gut microbiome

The meticulous and unprecedented work started with a complete survey of the bacteria present in the capybara’s intestine, in addition to the expressed genes and metabolites produced from plant fibers. To understand the processes of depolymerization of lignocellulosic fibers and the efficient transformation of sugars into energy, a vast combination of techniques, methodologies and resources, including synchrotron light at the MX2 and SAXS1 beamlines of the Brazilian Synchrotron Light Laboratory (LNLS), was required, from the population scale of microorganisms to the atomic and molecular level of enzymes.

Read more the the LNLS website

Advances in understanding superconducting material

2022/03/152022/03/24

Superconductivity has the potential to revolutionize technology, whether in lossless power transmission, more efficient electric motors and other applications. Recently these investigations have gained a new ally: Sirius

Imagine a future with batteries that don’t need charging, electric cars at more affordable prices, highly efficient electric motors and cheaper electricity due to ease in their transmission and storage. Gaining a deeper knowledge of the phenomenon of superconductivity is the key to this true technological revolution, which would have a potential impact on all types of electrical equipment.

This is because superconductivity is the property that allows certain materials to conduct electrical current without resistance and therefore without loss of energy. In Brazil, about 7.5% of electricity is lost in transmission and distribution, since the materials of these systems dissipate part of the energy, for example, in the form of heat. Also electric cars, even though they are much more efficient than ordinary combustion-powered cars, still lose up to 15% of the energy when charging batteries.

In view of the importance of this field, the National Center for Research in Energy and Materials (CNPEM), an organization supervised by the Ministry of Science, Technology of Innovations (MCTI), has been actively working to advance the understanding of the phenomenon of superconductivity. One of the research fronts in this area seeks to develop new tools for the experimental study of the physical phenomenon of superconductivity with the aid of superpotent X-rays generated by Sirius.

Read more on the Sirius website

Image: The Ema light line is one of the most advanced scientific tools for experiments seeking solutions for technologies involving superconductivity

Civil engineer plays key role in construction of Brazil’s light source

2021/12/162021/12/16

Sirius is the only light source in Latin America and is located at the Brazilian Center for Research in Energy and Materials. Mayara Adorno is a civil engineer and her role has been to oversee the technology control of the structures that house the synchrotron machine.

In her #LightSource Selfie, Mayara explains how she was attracted by the opportunity to work on a large project, taking it from paper plans through to completion. As with all large scale science facility construction projects, there were daily challenges for Mayara and her engineering colleagues. She says, “I’ve learned a lot from the project and this was very important for my professional and personal growth. I would advise any young engineer not to give up on your dreams and, this way, become a person who always wants to be open to learn and teach.” “It makes me really proud to know that Sirius has turned into the great science infrastructure from the efforts and dedications of many professionals from different areas, including myself.”

Mayara Adorno, Civil Engineer, at Sirius

Channeling light into nanobelts

2021/05/072021/05/13

CNPEM/MCTI researchers and collaborators investigate the confinement of long infrared waves in tin oxide nanobelts.

Infrared light is a band of the electromagnetic spectrum whose waves have lengths ranging from 750 nanometers to 100 microns. Three sub-bands can be defined within this spectral range, called near, medium and far infrared. Near infrared is routinely applied to remote controls, presence sensors and other metrology tools while medium infrared is explored in sensors and heat cameras. Finally, far infrared, commonly referred to as terahertz radiation because it is close to these frequencies, is used in non-destructive probes and gas spectrometers.

Far infrared is a low-energy and non-destructive radiation, suitable for applications in biological materials. It also has a high penetration in materials allowing its use in the non-invasive inspection of goods and people. In addition, this band has the ability to excite vibrational and rotational modes of countless molecules in gases and liquids, which enables the identification and study of new materials. Despite these numerous unique properties, the far infrared band has long been a little explored field of science due to the limited availability of sources and detectors in this energy range. However, in recent years, advances in electronics and optics have made numerous advances in this area possible.

In phase with technological advances in the detection and emission of infrared radiation and driven by the arrival of two-dimensional materials, infrared nanophotonics has been dedicated to studying new materials, such as graphene, in order to explore their properties and their use in this energy range. In this context, nano-structured semiconductor oxides have gained relevance given the abundance of elements with chemical affinity with oxygen combined with the variety of ways in which they can be synthesized: nanoparticles (0D), nanowires (1D), nanofilms (2D), nanocubes (3D), among others. However, the confinement and manipulation of long waves in the infrared region in these materials remain poorly developed subjects.

As such, researchers from the Brazilian Center for Research in Energy and Materials (CNPEM), a private non-profit organization under supervision of the Brazilian Ministry of Science, Technology, and Innovations (MCTI), and collaborators from Brazil and abroad studied the confinement of long infrared waves in tin oxide (SnO₂) nanobelts. To this end, the group combined Infrared Nanospectroscopy experiments performed on synchrotron light sources, UVX from the Brazilian Synchrotron Light Laboratory (LNLS) and ALS from the Lawrence Berkeley National Laboratory (USA), and on the free electron laser from Helmholtz-Zentrum Dresden-Rossendorf (Germany).

Read more on the LNLS website

Image: Experimental scheme showing the far infrared beam illuminating a metallic atomic force microscopy tip (nano-antenna) for the nanospectroscopy experiment. Infrared radiation is confined to the apex of the tip in a region of 25 nm

FIRST EXPERIMENTS ARE CARRIED OUT ON SIRIUS

2020/07/112020/07/16

The new Brazilian synchrotron light source, Sirius, from the Brazilian Synchrotron Light Laboratory (LNLS) at the Brazilian Center for Research in Energy and Materials (CNPEM), carried out the first experiments on one of its beamlines this week. The first research station to start operating, still in the commissioning stage, can reveal details of the structure of biological molecules, such as viral proteins. These first experiments are part of an effort by CNPEM to provide a cutting-edge tool to the Brazilian scientific community working in SARS-CoV-2 research.

In these initial analyses, CNPEM researchers observed crystals of a coronavirus protein, essential for the development of COVID-19. The first results reveal details of the structure of this protein, important for understanding the biology of the virus and supporting research that seeks new drugs against the disease.

>Read more on the LNLS website

First x-ray microtomography images obtained at Sirius

2019/12/192019/12/20

Two days after storing electrons in Sirius’ storage ring, the CNPEM´s team have performed the first x-ray microtomography analysis at the new Brazilian synchrotron light source. Through a simple proof of concept experiment, using less than ten thousandth of the expected power, it was possible to observe the arrival of synchrotron light for the first time in one of Sirius’ future experimental stations. This is a major milestone for the project, and a victory for Brazil’s science and technology.

“These early rock microtomography demonstrate the functionality of this great machine, designed and built by Brazilians to bring our science to a new level. Sirius is still in the early stages of commissioning, but these early tests that allowed X-ray images to be made ensure that the future will be very bright! We are very excited about the possibility to provide to the Brazilian scientific community a new level of experimental techniques as soon as possible”, said Antonio José Roque da Silva, Director General of CNPEM and the Sirius Project.
The first images were taken at one of the beamlines set up for testing, using X-ray tomography imaging techniques. These analyses mark another important milestone in the Sirius commissioning process. The team is now dedicated to achieving higher and higher currents needed to produce synchrotron light of enough intensity for the first scientific experiments.

>Read more on the LNLS website

Image: (screenshot) Projection of a carbonate rock sample, which has the same composition of the rocks from the Brazilian pre-salt reservoirs.

Sirius reaches his first stored electron beam

2019/12/172019/12/19

The new Brazilian synchrotron light source continues its successful commissioning

On Saturday, December 14th, CNPEM’s team stored electrons in Sirius’s storage ring for several hours. This is a prerequisite for producing synchrotron light, and it happens only a few weeks after the first electron loop around the main accelerator was achieved.
In addition, on Monday, December 16th, with the connection of the accelerator to one of the beamlines set up for testing, it was possible to receive the first X-ray pulse, still discrete due to the small number of circulating electrons.
The achievement came after an intense and thorough work of adjusting hundreds of equipment parameters, another very important milestone in the Sirius commissioning process. The team is now dedicated to achieving higher and higher currents needed to produce synchrotron light of enough intensity for the first scientific experiments.
Sirius is the largest and most complex scientific infrastructure ever built in Brazil and one of the first 4th generation synchrotron light source to be built in the world and it was designed to put Brazil at the forefront of this type of technology.

>Read more on the LNLS website

One of Sirius’ most important steps: first electron loop around the storage ring

2019/11/282019/12/02

This is one of the most important stages of the largest scientific project in Brazil .

The Sirius project has just completed one of its most important steps: the first electron loop around its main particle accelerator, called the Storage Ring. In this large structure, 518 meters in circumference, the electrons accelerated to very high energies produce synchrotron light: a very bright light used in scientific experiments that could revolutionize knowledge in health, energy, materials and more.
The first loop demonstrates that thousands of components such as magnets, ultra-high-vacuum chambers and sensors are working in sync, and that the entire structure, with parts weighing hundreds of kilograms, have been aligned to micrometer standards (up to five times smaller than a strand of hair) needed to guide the trajectory of the particles.
Sirius is the largest and most complex scientific infrastructure ever built in Brazil and one of the first 4th generation synchrotron light source to be built in the world and it was designed to put Brazil at the forefront of this type of technology.

The next steps of the project include concluding the assembly of the first beamlines: the research stations where scientists conduct their experiments. These stations allow researchers to study the structure of virtually any organic and inorganic materials, such as proteins, viruses, rocks, plants, soil, alloys, among many others, in the atomic and molecular scale with very high resolution and speed.

>Read more on the LNLS (CNPEM) website

Picture: first loop around the storage ring.

Monitoring food safety of marine fishes

2019/08/282019/09/19

Research investigates ways to convert titanium dioxide into a new photoactive material in the visible light range.

The search for clean and renewable energy sources has intensified in recent years due to the increase in atmospheric concentration of greenhouse gases and the consequent increase in the average temperature of the planet. One such alternative source is the conversion of sunlight into electricity through photovoltaic panels. The efficiency in this conversion depends on the intrinsic properties of the materials used in the manufacturing of the panels, and it increases year by year with the discovery of new and better materials. As such, solar energy is expected to become one of the main sources of electric energy by the middle of this century, according to the International Energy Agency (IEA).

Titanium dioxide ( $T i O_{2}$ ) is an abundant, nontoxic, biologically inert and chemically stable material, known primarily as a white pigment used in paints, cosmetics and even toothpastes. $T i O_{2}$ is also often used in sunscreens since it is especially capable of absorbing radiation in the ultraviolet region. However, this same property severely limits the use of $T i O_{2}$ for solar energy conversion, since the ultraviolet emission comprises only 5 to 8% of the total energy of the solar light. Can this $T i O_{2}$ property be extended to the visible light region to increase the conversion of sunlight into electricity? To answer this question, Maria Pilar de Lara-Castells et al. [1] conducted an innovative research in which they discuss how a special treatment can change the optical properties of $T i O_{2}$ .

>Read more on the LNLS website

Image: Joakant (Pixabay)

Enhancing solar energy production

2019/07/102019/09/20

Research investigates ways to convert titanium dioxide into a new photoactive material in the visible light range.

Can this $T i O_{2}$ property be extended to the visible light region to increase the conversion of sunlight into electricity? To answer this question, Maria Pilar de Lara-Castells et al. [1] conducted an innovative research in which they discuss how a special treatment can change the optical properties of $T i O_{2}$ .

Analyzing the structural disorder of nanocrystals

2019/05/222019/05/28

Research applies unprecedented technique in Brazil for the investigation of crystalline nanoparticles

The development of faster and more efficient electronic devices, better catalysts for the chemical industry, alternative energy sources, and so many other technologies depends increasingly on the in-depth understanding of the behavior of materials at the nanometer scale.
The properties of particles on this scale may be completely different from the properties of the same material in its macroscopic version. In addition, nanoparticles of different sizes and shapes can have completely different characteristics, even though they are formed by the same material.
The possibility of regulating the optical and electrical properties of nanoparticles by controlling their composition, shapes and sizes opens the door to an immense variety of applications. In this context, nanocrystals – nanometric particles that have a crystalline structure – have attracted great interest.
A crystal is a type of solid whose atoms or molecules are arranged in a well-defined three-dimensional pattern that repeats itself in space on a regular basis. The optical and electrical properties of crystalline materials depend not only on the atoms or molecules that constitute them but also on the way they are distributed. Therefore, defects or impurities present during crystal formation cause a disorder in the crystal structure. The consequent modification in the electronic structure of the crystal can lead to changes in its properties.

>Read more on the Brazilian Light Source Laboratory website
Image: PDF analysis obtained from electron diffraction data for nanocrystals before (ZrNC-Benz) and after ligand exchange (ZrNC-OLA).
Credit: Reprinted with permission from J. Phys. Chem. Lett. 2019, 10, 7, 1471-1476. Copyright 2019 American Chemical Society.

Control of light at the nanoscale

2019/05/092019/05/27

Research evaluates combination of graphene and hexagonal boron nitride for opto-electronic devices of the future

Photonics is the science that investigates phenomena related to light, such as its generation, transmission and detection. Its applications can be found in a wide range of technologies that directly impact our daily life: lasers used in surgery, fiber optics for data transmission, and screens of high definition TVs and smartphones. These advances are only possible by the in-depth knowledge of the interaction of light with supercompact electronic components.
The latest frontier of photonics is the production of nanoscale devices capable of transmitting information by means of light signals, called nanophotonic or optoelectronic devices. When compared to the already established electronic components, the new nanodevices will carry a greater volume of information at a faster pace.
Today, several research groups around the world are dedicated to building ultrathin photonic devices with outstanding performance. However, such development requires materials that have appropriate characteristics, besides being efficient and inexpensive.
One of the materials of interest is graphene, formed by a single layer of carbon atoms obtained from graphite. Graphene is a conductor with excellent properties that can be easily altered by applying electric fields or light. In addition, several other interesting structural, electronic and optical properties can be obtained by combining graphene with other materials. One of these combinations under study is the system formed by graphene in contact with a hexagonal boron nitride crystal (hBN), also a few molecules thick. This system allows the control of light transport on a nanometer scale.

Image: Schematics of the Graphene-hBN and the experimental analysis using infrared nanospectroscopy. Reprinted with permission from Nano Lett. 2019, 19, 2, 708-715.
Copyright 2019 American Chemical Society.