Tag: catalysis

Catching “Hydrogen Spillover” onto a Catalytic Surface

Catching “Hydrogen Spillover” onto a Catalytic Surface

Researchers uncovered the precise mechanism of hydrogen spillover (H2 splitting and migration) onto a catalytic surface by watching it happen under various conditions at the Advanced Light Source (ALS).

The research lays the foundation for designing more efficient catalysts and storage materials essential for next-generation hydrogen energy technologies.

Hydrogen on the move

The splitting and migration of molecular hydrogen (H2) over a catalytic surface (a process known as “hydrogen spillover”) is a fundamental yet elusive phenomenon in catalysis that affects a wide range of uses, from hydrogenation (which can be used to upgrade or purify crude oil components) to energy storage (when bonded to a metal, hydrogen can be stored in the solid state). Despite its importance, direct experimental evidence capturing the real-time mechanistic steps of hydrogen spillover remains scarce.

In particular, tungsten oxide (WO3), a widely used catalytic material, exhibits dynamic interactions with hydrogen, yet the precise nature of these interactions has been a subject of long-standing debate, especially for distinguishing the chemical dynamics occurring on the surface from those in the bulk.

This research was driven by the need to resolve these ambiguities using ambient-pressure x-ray photoelectron spectroscopy (APXPS), which provides direct spectroscopic evidence of the spillover process as it unfolds. By integrating experimental observations with theoretical models, the researchers unlocked a comprehensive understanding of how hydrogen interacts with reducible oxide surfaces and influences their catalytic properties.

Operando APXPS at the ALS

This study focused on WO3 thin films “decorated” with Pt metal clusters that facilitate hydrogen activation and dissociation. To directly visualize the stepwise evolution of hydrogen spillover on WO3, the researchers employed APXPS at ALS Beamline 9.3.2, a technique pioneered at the ALS and uniquely suited for studying solid–gas interfaces in real time under realistic (“operando”) reaction conditions.

APXPS detected the oxidation states of tungsten and the presence of surface hydrogen species as the samples were exposed over time to hydrogen gas at various temperatures. The tunable incident photon energy allowed selective analysis of different elements (including differentiating between various hydrogen species—molecular, protonic, or hydride-like) at variable depths, enabling the researchers to track hydrogen-induced changes with high precision. The ability to collect real-time spectra while exposing the sample to hydrogen enabled the detection of intermediates that would be difficult to observe with other methods.

Furthermore, by combining the APXPS experimental observations with first-principles-based microkinetic modeling and simulations, the researchers gained a comprehensive understanding of the reaction mechanisms underlying hydrogen spillover.

Read more on ALS website

Image: Artistic depiction of a tungsten trioxide (WO3) surface (purple/red) “decorated” with a platinum nanocluster (metallic gray). Green arrows trace the evolution of hydrogen (white) from gas form (H2) to dissociation into H+ on the platinum, to spillover (migration) onto the WO3 surface, and, at elevated temperatures, desorption as water vapor (H2O) and diffusion into the bulk.

Aluminium made visible

Aluminium made visible

Zeolites are highly porous substances that facilitate numerous reactions in the chemical industry. In collaboration with the J. Heyrovský Institute of Physical Chemistry in Prague, PSI researchers have succeeded for the first time in precisely determining the position of the aluminium atoms in the zeolite lattice – an important step on the path to tailor-made catalysts. The study has now been published in the journal Science.

In cat litter they absorb unpleasant odours; in detergents they soften the water, protecting washing machines; and in refineries they help in the production of petrol – zeolites are used in many different places. We encounter them in our daily lives, and they are the most frequently used catalysts for promoting chemical reactions in industry. 

Their many useful properties stem from their porous, lattice-like structure. Silicon and aluminium atoms are linked by oxygen atoms to form a crystalline framework with numerous small pores and channels. Zeolites can capture molecules from gases or liquids, hold on to them and help to convert them into other molecules. But it is only now that PSI researchers have managed to draw a more precise picture of a zeolite structure: they have located the position within the lattice of the aluminium atoms that trigger the chemical reactions.

“Zeolites are extremely important materials, but we still don’t fully understand how they work,” says Jeroen van Bokhoven of PSI’s Center for Energy and Environmental Sciences. Previous methods were able to determine the position of the atoms in the lattice but could not distinguish aluminium from silicon. The aluminium atoms play a particularly important role, however: they form the active sites that allow certain reactions to take place. This is why scientists are particularly interested in locating them. 

The exact position of the aluminium atoms determines how effective the zeolite in question is as a catalyst and for which chemical reactions. Different zeolite structures are used for different reactions. The PSI researchers used their method to investigate the zeolite ZSM-5, a particularly important industrial catalyst with an unusually complex structure. “We reckoned that if we could do this with ZSM-5, the other zeolites wouldn’t be a problem,” says Jeroen van Bokhoven.

The SLS as a large microscope

The question of where exactly the aluminium atoms are located in the zeolite structure has long vexed scientists. “The new method we have developed solves a problem that previously seemed unsolvable,” says Przemyslaw Rzepka, first author of the study. Rzepka, who used to work with Jeroen van Bokhoven at PSI as a postdoc, is now a scientist at the J. Heyrovský Institute of Physical Chemistry in Prague. 

Until now, scientists have used ordinary X-rays to look inside zeolites and learn about the structure of their pores and channels. The X-rays are scattered by the atoms and the resulting diffraction pattern allows conclusions to be drawn about the three-dimensional structure of the material. The problem is that the elements silicon and aluminium are right next to each other in the periodic table, and this means that in experiments using ordinary X-rays they look more or less identical. Spectroscopic methods, on the other hand, rely on the way a material absorbs radiation or alters it. Because aluminium and silicon absorb radiation differently, the two types of atoms can be distinguished – however, such methods cannot determine their positions in space, only the number and type of atoms in a material.

The PSI scientists’ solution was to combine the two techniques. They directed soft X-rays, which have comparatively low energies, at the materials at the Swiss Light Source SLS. “The pattern created when the X-rays are scattered by the material tells us the position of the atoms. We then examine these positions using spectroscopic methods to identify the particular type of atom that is sitting there,” explains Przemyslaw Rzepka. 

This clever combination was made possible by the unique X-ray diffractometer for soft X-rays at the SLS Phoenix beamline. The researchers were able to see, for the first time, a difference between silicon and aluminium atoms and determine the exact location of the active sites where the reaction takes place.

Read more on PSI website

Image: Jeroen van Bokhoven (left) and his team at the Paul Scherrer Institute PSI in Villigen are carrying out research into zeolites. His research group has succeeded for the first time in determining the position of the aluminium atoms that are crucial to the catalytic properties of the materials. This was possible thanks to the Swiss Light Source SLS, where scientist Thomas Huthwelker (right) works.

Credit: Paul Scherrer Institute PSI/Markus Fischer

Structure of next-generation catalysts

Structure of next-generation catalysts

In a study published in Molecular Catalysis researchers from West Pomeranian University of Technology in Szczecin, Warsaw University of Technology, Graz University of Technology, and National Synchrotron Radiation Centre SOLARIS explored the structure of next-generation catalysts for ammonia synthesis. Only the combination of standard laboratory measurements with possibilities of synchrotron XANES/EXAFS allowed understanding mechanisms leading to the active form of the synthesised material.

To meet the demand from agriculture, the ammonia industry consumes ca. 2% of world energy production, which is a consequence of the high temperature (400-500°C) and high pressure (10-30 MPa) required for the Haber-Bosch process ongoing on widely used iron-based catalysts. The development of new-generation catalysts is essential to lower the operating costs and reduce the CO2 emission of this process. Ammonia is also positioned as a potential form of synthetic fuel of the future. As a result, research and development initiatives focusing on the production of so-called green ammonia, which is produced using hydrogen from water electrolysis powered by renewable energy sources, are gaining momentum.


Development of the new catalyst is high-throughput work, based on screening tests, which allow for the selection of e.g. the optimal carrier, deposition method of the active phase, and load of the active phase. After several dozens of tests, we have designed a promising new catalyst, obtained by impregnation of the γ-Al2O3 with the cobalt and molybdenum compounds, followed by the activation process. The catalytic activity and stability of the obtained catalysts, tested in a laboratory fixed bed reactor under atmospheric pressure at 500 °C, were promising compared to the reference state-of-art Co3Mo3N and the commercial iron-based catalyst. However, the determination of the active phase structure, necessary to fully understand the nature of the catalyst, with standard laboratory methods was ambiguous. Thus, selected obtained catalysts were examined with the help of powerful synchrotron XANES/EXAFS measurements at the ASTRA beamline. 

Read more on SOLARIS website

Image: Scheme of the catalyst synthesis protocol including wet impregnation of support and activation of precursor in ammonia, resulting in highly active and stable catalyst.

A Greener Route to Gold Nanoparticles

A Greener Route to Gold Nanoparticles

High-resolution scanning transmission electron microscopy confirms a new, mild approach to metal nanoparticle synthesis

Gold nanoparticles (NPs) are used in a variety of applications including catalysis, drug delivery, biosensing, and electronics. Traditional methods for producing gold NPs often involve harsh conditions and tend to produce larger NPs (10-200 nm). Smaller gold NPs (less than 10 nm) are more desirable for catalysis, because their higher surface area to volume ratio offers a higher number of catalytically active surface sites, and hence greater reactivity. There is, therefore, a need to develop more sustainable methods of synthesising metal nanoparticles that allow precise control over their size and shape. However, bio-based synthesis methods using plant extracts or microorganisms often result in poor uniformity. In addition, there is a lack of sustainable methods for synthesising core-shell NPs, which are composed of two or more materials. In work recently published in Angewandte Chemie, researchers from the University of Oxford demonstrated a mild synthesis method that produced NPs with high uniformity of size and shape. Using high-resolution scanning transmission electron microscopy (HR-STEM) at the electron Physical Science Imaging Centre (ePSIC), they showed that the synthesis could also form core-shell Au@Pt nanoparticles. Their results suggest that this approach could be used to develop a new type of self-synthesised chemo-biocatalyst with wide-ranging applications in biotechnology.

Overcoming challenges in green nanoparticle synthesis

Metal nanoparticles have a wide variety of uses, from drug delivery to catalysis. Smaller NPs are more desirable for catalysis due to their greater reactivity, and gold is often combined with platinum group metals in core-shell NPs to improve reactivity and stability. As traditional synthesis methods rely on harmful chemicals or high temperatures, there is a need to develop more sustainable processes. However, bio-based strategies using plant extracts or micro-organisms struggle to produce NPs with the high uniformity required.

In this work, a research team from the University of Oxford developed a more sustainable method for synthesising metal nanoparticles using an isolated enzyme, NAD+ reductase (NRase), to achieve better control over size, shape, and catalytic activity.

They used NRase to reduce gold (Au) salts, in a process that involves the oxidation of NADH at the enzyme’s active site, which releases electrons used for the reduction of the metal salts. The new process resulted in the formation of highly uniform, spherical gold nanoparticles. By varying the concentration of NRase, the researchers were able to precisely control the size of the resulting nanoparticles; higher concentrations of NRase led to smaller nanoparticles, indicating that the enzyme acts as a template for nanoparticle formation.

The team was also able to use the process to synthesise core-shell NPs. After forming a gold NP, they found that adding platinum salts and more NADH resulted in the deposition of a platinum (Pt) shell over the gold core.

HR-STEM confirms nanoparticle structures

The team used several imaging techniques to characterise the synthesised nanoparticles, including UV and visible light spectroscopy to monitor the formation of nanoparticles and to estimate their average diameter and transmission electron microscopy (TEM) to directly observe the size, shape, and structure of the nanoparticles. Using HR-STEM at ePSIC allowed them to confirm the core-shell structure of Au@Pt NPs, with the results showing a higher ratio of platinum in the outer layers and gold (Au) in the centre.

Christopher Allen, Principal Electron Microscopist at ePSIC commented:

At ePSIC, the ability to simultaneously acquire atomic resolution images – which tells us where the atoms are – with energy dispersive X-ray spectroscopy – which tells us what the atoms are – is an incredibly powerful tool. This enables us to develop a fundamental understanding of the chemistry that is occurring during a catalytic process, which in turn can help us to develop increasingly efficient catalyst materials. The work by Professor Vincent’s group at ePSIC is a great example of how information about atomic structure can enable us to understand the macroscopic properties of materials.

Read more on Diamond website

Users of ALBA create the most porous zeolite to date

Users of ALBA create the most porous zeolite to date

A team from the Materials Science Institute of Madrid -CSIC) leads an international research that synthetized a zeolite with extra-large pores by expanding and connecting silica chains. This material has applications in water and gas decontamination and catalysis. Experiments carried out at the MSPD beamline of the ALBA Synchrotron had a key role in determining the structure of the zeolite.

A team from the Materials Science Institute of Madrid (ICMM-CSIC) leads an international research that has succeeded in creating the world’s most porous zeolite. The study, published yesterday in the journal Nature, opens up new avenues for water and gas decontamination and “demonstrates that it is possible to make more porous materials that are stable,” says Miguel Camblor, researcher at the ICMM-CSIC and lead author of the study.

Zeolites are microporous crystalline silicates. These are materials with applications in decontamination, catalysis, gas adsorption, and cation exchange. For decades, obtaining stable zeolites with greater porosity and, therefore, capacity for absorption and processing of large molecules, has been an important scientific goal. However, this is not a simple challenge: “until recently, it challenged our synthetic capacity,” indicates Camblor.

The team already developed in recent years two zeolites with “extra-large” pores in the three spatial directions that also exhibited high stability. On this occasion, they have created a stable aluminosilicate zeolite with extra-large pores open through rings of more than 12 tetrahedra, capable of processing even larger molecules.

“The structure of this zeolite presents unprecedented characteristics and demonstrates that with different methods, things that were believed impossible can be found, such as this world record in porosity,” highlights Camblor, who indicates that they have already used the zeolite for the absorption of volatile organic compounds.

To determine the structure of the zeolite, the research team has combined electron diffraction techniques and powder X-ray diffraction, the latter available at the MSPD beamline of the ALBA Synchrotron. The X-rays produced at the ALBA’s accelerator provided crucial information on the position of the atoms in the zeolite structure.

Read more on the ALBA website

Image: Structure of the zeolite called ZEO-5

Credit: Nature

Unveiling finer details in the physics of materials

Unveiling finer details in the physics of materials

Scientists at the European XFEL’s SCS instrument routinely use a technique called transient X-ray absorption spectroscopy (XAS) to investigate materials that have applications in data storage and processing, catalysis, or in the search for room temperature superconductors. Investigating very small changes in the motion of electrons within a material’s structure on ultrashort timescales provides scientists with fingerprints of the complex processes at play within them. This helps them characterise samples that are important for energy and materials research.

Using the European XFEL’s brilliant pulses, researchers can overcome some of the issues of conventional transient XAS—such as long measurement times—but the varying intensity of European XFEL’s pulses provides its own challenges. Now, scientists at SCS have implemented a new sampling scheme for improving the efficiency of such measurements.

Read more on the European XFEL website

Image: The X-ray beam is split into three copies. Two of these copies are passed through identical samples of the material under investigation, with one of these samples also being illuminated by a laser (‘optical laser’ in the figure). This transforms it into a new state, interesting to researchers. From this, scientists are able to ‘subtract’ detrimental noise, revealing the finest details of the sample under investigation.

Graphene coated nickel foams for hydrogen storage

Graphene coated nickel foams for hydrogen storage

Hybrid composites where graphene (Gr) and other 2D materials replicate the meso-and micro-structure of 3D porous substrates have shown innovative functionalities in catalysis and energy-related fields. Concerning hydrogen storage, the high surface-to-volume ratio exhibited by both 2D and 3D components of the hybrid material is expected to increase the efficiency of surface chemisorption and bulk absorption of hydrogen in comparison to the flat counterparts. To explore this possibility, we have grown single layer Gr on porous nickel foams and have investigated the interaction with H atoms as a function of the temperature by using X-ray photoelectron spectroscopy and thermal programmed desorption (TPD) at the SuperESCA beamline of Elettra.

The growth of Gr on the Ni foam was obtained by exposing the sample at 773 K to ethylene. Selected C 1s spectra taken at increasing growth time are shown in Fig.1a. Upon exposure to ethylene, the carbide phases (N1-N4 components) observed in the pristine sample disappear, while new Gr components (labeled C0 and C1) progressively increase in intensity and eventually saturate. The component C0 is attributed to GrS regions grown on the (111) foam grains, where the interaction with the support is as strong as that between Gr and the ordered Ni(111) surface; C1 is attributed to GrW regions that are rotated with respect to (111) grains, or are grown on Ni grains exposing different orientations, and therefore, are interacting weakly with the support.

Read more on the Elettra website

Figure 1: a) C 1s spectra measured during the Gr growth after 0, 3,10,16 and 44 minutes of exposure to ethylene at 773 K and (bottom) at RT after growth; b) C 1s spectra acquired on the Gr/foam hydrogenated with the same H dose at the indicated temperatures TH and c) TPD curves measured during sample annealing.

Fig. 1b shows the C 1s spectra measured on the Gr/foam exposed to a flux of H atoms at temperatures TH between 78 and 298 K. Starting from TH=98 K, the C 1s line shapes appear broadened on the high binding energy (BE) side, due to the appearance of a component (labeled A) at 285.0 eV, and also on the low BE side, due to another component (labeled B) at 284.1 eV. A and B are ascribed to C atoms directly bonded to H atoms and to their first neighbors, and therefore indicate the occurrence of H chemisorption on Gr. From 198 K, some intensity is transferred from C0 to C1, because at this temperature the H atoms start to intercalate below GrS, which detaches gradually from the substrate. The intercalation under the nearly free-standing GrW remains undetected, because here the penetration of H underneath does not cause any measurable extra-shift of the C1 component.

Fig. 1c shows H2 TPD curves measured while heating the Gr/foam hydrogenated at increasing TH. The desorption of H atoms chemisorbed on Gr originates solely the weak peak G at ~ 650 K.  Hence, all other TPD features correspond to the desorption of H atoms intercalated below Gr and residing at the Ni foam surface or even diffused into the Ni bulk. Hence, differently from GrS, where H atoms intercalate only for TH ~ 198 K, intercalation below GrW occurs at much lower temperatures. The TPD curves up to TH=173 K are dominated by the D peak, due to the desorption of H atoms penetrated in metastable subsurface sites of the Ni foam. The H2 release at higher temperatures is related to the slower desorption of bulk H atoms and to the release of H atoms chemisorbed on the Ni surface. It turns out that the highest quantity of loaded hydrogen is detected for TH= 113 K and amounts to ~ 5 times the quantity which saturates the Ni (111) surface with equivalent macroscopic lateral dimension.

Success from widening access to basic science research tools and synchrotron expertise in Africa

Success from widening access to basic science research tools and synchrotron expertise in Africa

A focus of UNESCO’s International Year of Basic Sciences for Sustainable Development is ‘enhancing inclusive participation in science’. Diamond Light Source was a key partner in START, a collaborative project that sought to foster the development of Synchrotron Techniques for African Research and Technology (START), which ran from 2018 to 2021 with a £3.7 M grant from the Global Challenges Research Fund (GCRF) provided by the UK’s Science and Technology Facilities Council (STFC). Today on World Science Day for Peace and Development, we are highlighting health and energy research enabled by START.

Diamond played a pivotal role in the project, providing African scientists with crucial access to world class synchrotron techniques, beamtime, training and mentoring. Research focused on structural biology and energy materials to address key United Nations’ Sustainable Development Goals for health (SDG 3), energy (SDG 7), climate (SDG 13), and life-long learning (SDG 4).

Addressing worldwide energy challenges

Catalysis is essential for the development of a sustainable world and was a focus of the energy materials arm of the grant, along with solar energy, which is a well-recognised sustainable energy solution. These are just two areas in the physical sciences that were investigated as part of START.

Working towards better renewable energy solutions

Catalysis has many applications in renewable energy, where waste biomass is converted to liquid biofuels, or waste CO2 is converted to high value chemicals that can be used in our daily life, or as an alternative to fossil fuels. These applications rely on catalysts but to make this process more sustainable and efficient, advanced techniques are required to understand how the catalysts work under operating conditions. A group of START collaborators used Diamond to understand more about catalyst materials. They were investigating furfural, a bio-derived molecule that can be converted to many useful products that can be used for renewable energy. However, bio-derived compounds are highly functionalised – many parts of the molecular structure can undergo chemical change. Palladium (Pd) nanoparticles are widely used as an active component in furfural hydrogenation – a specific type of reaction that involves the addition of hydrogen to a compound – however, selectivity to specific products is a big challenge. Using X-ray absorption spectroscopy at Diamond, the team demonstrated that a Pd/NiO catalyst can hydrogenate furfural using a dual site process. This work has significant implications for the upgrading of bioderived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals.

Read more on the Diamond website

Image: START logo

High entropy alloys: structural disorder and magnetic properties

High entropy alloys: structural disorder and magnetic properties

High-entropy alloys (HEAs) are promising materials for catalysis and energy storage, and at the same time they are extremely hard, heat resistant and demonstrate great variability in their magnetic behaviour. Now, a team at BESSY II in collaboration with Ruhr University Bochum, BAM, Freie Universität Berlin and University of Latvia has gained new insights into the local environment of a so-called high-entropy Cantor alloy made of chromium, manganese, iron, cobalt and nickel, and has thus also been able to partially explain the magnetic properties of a nanocrystalline film of this alloy.

High entropy alloys or HEAs consist of five or more different metallic elements and are an extremely interesting class of materials with a great diversity of potential applications. Since their macroscopic properties are strongly dependent on interatomic interactions, it is utterly interesting to probe the local structure and structural disorder around each individual element by element-specific techniques. Now, a team has examined a so called Cantor alloy – a model system to study the high-entropy effects on the local and macroscopic scales.

Read more on the HZB website

Image: The Cantor alloy under study consists of chromium (grey), manganese (pink), iron (red), cobalt (blue), and nickel (green). X-ray methods allow to probe each individual component in an element-specific way.

Credit: © A. Kuzmin/University of Latvia and A. Smekhova/HZB

European Young Chemists’ Award for Sebastian Weber

European Young Chemists’ Award for Sebastian Weber

In recognition of Sebastian’s PhD thesis on hard X-ray microscopy, tomography, and application of synchrotron radiation in catalysis research

Sebastian Weber, a recent PhD graduate at the Institute for Chemical Technology and Polymer Chemistry (ITCP) / Institute for Catalysis Research and Technology (IKFT) at Karlsruhe Institute of Technology (KIT), was awarded the Gold Medal in the PhD category of the European Young Chemists‘ Award. The award is presented every two years during the EuChemS Chemistry Congress on behalf of the Società Chimica Italiana (SCI) and the European Chemical Society (EuChemS). The prize highlights excellent research from young / early stage researchers across all fields of chemistry and chemical sciences. During his PhD phase, Sebastian Weber studied materials used in heterogeneous catalysis with a broad range of spatially-resolved X-ray characterisation methods, in order to gain a deeper understanding of the structure and function of catalysts. The project made extensive use of synchrotron radiation, specifically X-ray microscopy and tomography as emerging methods in catalysis research. This success on the European level highlights the leading role which synchrotron science has to play in the study of matter.

Catalysis plays a crucial role in sustainable chemical production, chemical energy conversion and storage, among many others, and is a key technology area in synchrotron radiation research. During his PhD work at Karlsruhe Institute of Technology, Sebastian Weber studied catalysts for CO2 methanation using spatially-resolved characterisation tools including X-ray microscopy and tomography. These diverse X-ray imaging methods were exploited to study the 3D structure of catalytic materials over a range of length scales, addressing various levels of hierarchical structural features which are critical to understanding catalyst performance. This topic is a special focus of the Young Investigator Group of Dr. Thomas Sheppard at KIT, who supervised and secured funding for the project, within the wider group of Prof. Jan-Dierk Grunwaldt.

Only a handful of research groups worldwide are currently active in the field of X-ray microscopy applied to catalysis research, highlighting the emerging role of this vibrant research field. During his PhD work, Sebastian Weber in particular worked to develop applications of hard X-ray ptychography and ptychographic X-ray tomography (PXCT) to study catalyst pore structures, structural evolution under reaction conditions, and the effects of catalyst deactivation. These methods routinely reach spatial resolution below 50 nanometres (0.001 x diameter of a human hair), and have been applied so far on samples up to 50 micron in diameter (ca. the diameter of a human hair). The further development of ptychography holds excellent potential for catalysis and materials research, particularly in the age of fourth generation light sources with improved coherence and decreased source emittance. The project resulted in several high quality publications in leading chemistry and materials journals, reflecting the knowledge gained regarding 3D structure of catalysts, and the potential for development of improved catalysts in future.

Sebastian Weber recently completed his doctorate with the title “Revealing Porosity and Structure of Ni-based Catalysts for Dynamic CO2 Methanation with Hard X-rays”, earning a distinction from KIT. Now his work was further recognised by securing the Gold Medal of the European Young Chemists’ Award at PhD level. The award is presented every two years during the EuChemS Chemistry Congress on behalf of the Società Chimica Italiana (SCI) and the European Chemical Society (EuChemS). The prize highlights excellent research from young / early stage researchers across all fields of chemistry and chemical sciences, and is therefore a highly competitive prize. After a pre-selection phase based on scientific excellence, the six finalists each held a presentation at the EuChemS Chemistry Congress in Lisbon, Portugal. The award not only highlights the excellent contribution of Sebastian Weber to the field of chemical sciences, but promotes in front a broad audience the essential role of synchrotron radiation in delivering future insights and innovations across the field of natural sciences.

Related articles on this research can be found in the Diamond Annual Review 2021-2022, “X-ray ptychography investigates coking of solid catalysts in 3D”, p.66-67, and on the DESY website

Image: Award ceremony during the 8th EuChemS Chemistry Congress in Lisbon, Portugal, Sebastian Weber (KIT, left), Prof. Floris Rutjes (President of the European Chemical Society, middle) and Prof. Angela Agostiano (Chair of the EYCA Award Committee, right).

Graphics: EYCA

#SynchroLightAt75 – Historical perspective of catalysis at Elettra

#SynchroLightAt75 – Historical perspective of catalysis at Elettra

“Catalysis, is a strange principle of chemistry which works in ways more mysterious than almost any other of the many curious phenomena of science” New York Times: June 8, 1923

Heterogeneous catalysis is one of the most extensively studied functional systems since it is in the heart of chemical industry, fuel, energy production and storage and also is part in the devices for environmental protection.

The key processes in heterogeneous catalysis occur at dynamic reactant/catalyst surface interfaces. Since these processes involve coupling between different electronic, structural and mass transport events at time scales from fs to days, and space scales from nm to mm, we are still far from full comprehension how to design and control the catalysts performance. In this respect the ultrabright and tunable light, generated at the synchrotron facilities, has opened unique opportunities for using powerful spectroscopy, spectromicroscopy, scattering and imaging methods for exploring the morphology and chemical composition of complex catalytic systems at relevant length and time scales and correlate them to the fabrication or operating conditions.

The very demanded for catalysis studies is the surface sensitive PhotoElectron Spectroscopy (PES), based on the photoelectric effect, for which Einstein won the 1921 Nobel Prize in Physics, and demonstrated for the first time in 1957 by Kai Siegbahn who was awarded the Nobel Prize in 1981. PES has overcome its time and space limitations for studies of catalytic surface reactions thanks to the synchrotron light, which also added the opportunity for complementary use of X-ray absorption spectroscopy. At Elettra, the first time resolved PES studies with model metal catalyst systems were carried out at SuperESCA beamline in 1993 and few years later PES microscopy instruments, Scanning PhotoElelectron Microscope (SPEM) and X-ray PhotoElectron Emission Microscope (XPEEM) at ESCAMicroscopy and Nanospectroscopy beamlines have allowed for sub-mm space resolved studies, including imaging of dynamic surface mass transport processes as well.

Implementation in the last decade of operando experimental set-ups at APE, BACH and ESCAMicroscopy experimental stations for bridging the pressure gap of PES investigations has led to significant achievements in monitoring in-situ chemical, electrochemical and morphology evolution of all types catalytic systems under reaction conditions. Further complementary studies using X-ray absorption spectroscopy in photon-in/photon-out mode, ongoing at the XAFS and TwinMic beamlines are filling some remaining knowledge gaps for paving the road towards knowledge-based design and production of these complex and very desired functional materials.

M. Amati, L. Bonanni, L. Braglia, F. Genuzio, L. Gregoratti, M. Kiskinova, A. Kolmakov, A.Locatelli, E. Magnano, A. A. Matruglio, T. O. Menteş, S. Nappini, P. Torelli, P. Zeller,” Operando photoelectron emission spectroscopy and microscopy at Elettra soft X-ray beamlines: from model to real functional systems”, J. Electr. Spectr. Rel. Phenom. (2019) doi: 10.1016/j.elspec.2019.146902.

For first SUPERESCA – A. Baraldi, G. Comelli, S. Lizzit, M. Kiskinova, G. Paolucci “Real-Time X-Ray Photoelectron Spectroscopy of Surface Reactions” Surf. Sci. Reports 49, Nos. 6-8 (2003) 169.

For XPEEM A. Locatelli and M. Kiskinova “Imaging with Chemical Analysis: Adsorbed Structures Formed during Surface Chemical Reactions” A European Journal of Chemistry, 12 (2006) 8890.

Image: From model to real catalysts: structural and chemical complexity

Lightsources.org virtual symposium recording

Lightsources.org virtual symposium recording

Lightsources.org was delighted to welcome over 500 attendees to our live virtual symposium to mark the 75th Anniversary of the first direct observation of synchrotron light in a laboratory. The event, which was chaired by Sandra Ribeiro, Chair of lightsources.org and Communications Advisor for the Canadian Light Source, was held on the 28th April 2022 and you can watch the recording via the YouTube link below.

We received some lovely feedback after the live event, including this comment from Jeffrey T Collins at the Advanced Photon Source, Argonne National Laboratory in Illinois.

 “I have worked at the Advanced Photon Source for over 32 years and I learned many things during this event that I never knew before.  It was quite informative.  I look forward to re-watching the entire event.”

Jeffrey T Collins, Mechanical Engineering & Design Group Leader at Argonne National Laboratory

The symposium began with a historical introduction from Roland Pease, freelance science broadcaster who has been an enthusiastic support of light sources for many years.

Roland’s talk was followed by experts from the field giving talks on their perspectives of synchrotron light related achievements that have been made since the 1st laboratory observation on the 24th April 1947.

Speakers were:

• Nobel Laureate Prof. Ada Yonath (Weizmann Institute of Science)

• Prof. Sir Richard Catlow (University College London)

• Prof. Henry Chapman (DESY)

• Dr Paul Tafforeau (ESRF)

• Dr Gihan Kamel (SESAME and member of the AfLS Executive Committee).

There followed a panel discussion with special guests who all made huge contributions to the development of the field. Our special guests were:

Herman Winick – Prof. of Applied Physics (Research) Emeritus at SLAC)

Ian Munro – Initiator of synchrotron radiation research at Daresbury Laboratory ,Warrington UK in 1970

Giorgio Margaritondo – one of the pioneers in the use of synchrotron radiation and free electron lasers

Gerd Materlik – former CEO of Diamond Light Source, the UK’s synchrotron science facility

Lightsources.org is hugely grateful to all the speakers, special guests and attendees who contributed to this event and made it such a special anniversary celebration for the light source community.

If you have any feedback or memories to share, please do contact Silvana Westbury, Project Manager, at webmaster@lightsources.org

For news, jobs, events and proposal deadlines, please visit the homepage

Science’s great strength is the universal language

Science’s great strength is the universal language

SSRL’s #LightSourceSelfie

Forrest Hyler is a PhD student at the University of California Davis and regular user of the Stanford Synchrotron Lightsource (SSRL). Forrest’s research involves exploring the structural and electronic properties of materials that are used as catalysts for carbon dioxide reduction in the lab. In his #LightSourceSelfie, Forrest describes his work as all encompassing as it involves studying materials related to a broad range of applications such as batteries, catalysis and the storage of radioactive materials. Forrest’s journey has involved a large range of scientists and he says, “The greatest part about science is that it’s kind of that universal language. You get to interact with people around the globe working together for a common goal to push science beyond the boundaries that we’ve ever been at before.”

Developing new alloys for hydrogen fuel and catalysis

Developing new alloys for hydrogen fuel and catalysis

An alloy is a metal that contains two or three different elements. Steel, for instance, is an alloy of iron and carbon that offers increased strength as a building material.

By mixing more elements together, scientists hope to create new and improved alloys with increased strength and improved corrosion resistance, which could help many industry sectors to reduce costs.

“The trouble is that when you try to make a traditional alloy with more than a couple of elements, the elements tend to separate from each other and clump together,” said David Morris, a PhD student in the Department of Chemistry at the Dalhousie University.

That’s why his research team is interested in alloys with five or more elements that have a highly disordered nature. This chaotic property causes the elements to disperse throughout the mixture and prevent clumping. “You can get alloys with elements that wouldn’t usually go together,” he said.

Morris and his colleagues, including Liangbing Hu’s group from the University of Maryland who synthesized the samples using a special carbothermal shock method, are investigating two alloy samples, one made of five elements and another with fifteen.

“Early experiments suggested that the five-element alloy has high catalytic activity for ammonia decomposition, a process used to make hydrogen fuel, but they potentially have all kinds of applications,” he said.

The team gathered data at the Advanced Photon Source (APS) in Illinois, thanks to the facility’s partnership with the Canadian Light Source (CLS) at the University of Saskatchewan. Using synchrotron light, Morris could analyze each element in their samples separately and spot the differences in the structures of the two alloys.

The researchers discovered that the fifteen-element alloy had some elements that showed oxidation and the length of some of the bonds between them increased. These properties, however, were not found in the five-element alloy, indicating the properties of these special alloys are highly dependent on their compositions.

“Increased oxidation means they are less stable, which could potentially increase the activity for catalysis,” said Morris. “And unusual bond lengths can change the properties and maybe make a more promising catalytic pathway.”

The group’s next step will be to try and link the changes in structure seen in this experiment to the alloys’ catalytic activity. “If we are able to find certain structural properties that are associated with a high catalytic activity, that would allow us to design more effective catalysts in the future,” said Morris.

Read more on the CLS website

Image: APS

Transition-metal dichalcogenide NiTe2: an ambient-stable material for catalysis and nanoelectronics

Transition-metal dichalcogenide NiTe2: an ambient-stable material for catalysis and nanoelectronics

Recently, transition-metal dichalcogenides hosting topological states have attracted considerable attention for their potential implications for catalysis and nanoelectronics. The investigation of their chemical reactivity and ambient stability of these materials is crucial in order to assess the suitability of technology transfer. With this aim, an international team of researchers from Italy, Russia, China, USA, India, and Taiwan has studied physicochemical properties of NiTe2 by means of several experimental techniques and density functional theory. Surface chemical reactivity and ambient stability were followed by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy (XAS) experiments at the BACH beamline, while the electronic band structure was probed by spin- and angle-resolved photoelectron spectroscopy (spin-ARPES) at the APE-LE beamline. 

Read more on the Elettra website

Image: a) Ni-3p core-level spectra collected from as-cleaved NiTe2 (black curves) and from the same surface exposed to 2·104 L of CO (red curves), H2O (green curves) and O2 (blue curves).  Credit: Adapted from “S. Nappini et al., Adv. Funct. Mater. 30, 2000915 (2020); DOI: 10.1002/adfm.202000915” with permission from Wiley (Copyright 2020) with license 4873681106527