water – Lightsources.org

Electrocatalysis – Iron and Cobalt Oxyhydroxides examined

2023/02/162023/02/23

A team led by Dr. Prashanth W. Menezes (HZB/TU-Berlin) has now gained insights into the chemistry of one of the most active anode catalysts for green hydrogen production. They examined a series of Cobalt-Iron Oxyhydroxides at BESSY II and were able to determine the oxidation states of the active elements in different configurations as well as to unveil the geometrical structure of the active sites. Their results might contribute to the knowledge based design of new highly efficient and low cost catalytical active materials.

Very soon, we need to become fossil free, not only in the energy sector, but as well in industry. Hydrocarbons or other raw chemicals can be produced in principle using renewable energy and abundant molecules such as water and carbon dioxide with the help of electrocatalytically active materials. But at the moment, those catalyst materials either consist of expensive and rare materials or lack efficiency.

Key reaction in water splitting

A team led by Dr. Prashanth W. Menezes (HZB/TU-Berlin) has now gained insights into the chemistry of one of the most active catalysts for the anodic oxygen evolution reaction (OER), which is a key reaction to supply electrons for the hydrogen evolution reaction (HER) in water splitting. The hydrogen can then be processed into further chemical compounds, e.g., hydrocarbons. Additionally, in the direct electrocatalytic carbon dioxide reduction to alcohols or hydrocarbons, the OER also plays a central role.

Read more on the HZB website

Image: LiFe_x-1Co_x Borophosphates have been used as inexpensive anodes for the production of green hydrogen. Their dynamic restructuring during OER as well as their catalytically active structure, have been elucidated via X-ray absorption spectroscopy.

Credit: © P. Menezes / HZB /TU Berlin

Water improves material’s ability to capture CO2

2020/02/272020/03/12

With the help of the Advanced Light Source (ALS), researchers from UC Berkeley and ExxonMobil fine-tuned a material to capture CO₂ in the presence of water.

About 65% of anthropogenic greenhouse gas emissions comes from the combustion of fossil fuels in power plants. So far, efforts to capture CO₂ from power-plant flue gases and sequester it underground have mainly focused on coal-fired power plants. However, in the United States, natural gas has surpassed coal in the amount CO₂ released, despite the fact that natural gas emits approximately half as much CO₂ per unit of electricity. Therefore, new materials are urgently needed to address this situation.

Not all combustion is alike

Compared to coal-fired power plants, natural gas combined cycle (NGCC) plants produce flue gases with low CO₂ concentrations. This reduces the carbon footprint, but increases the technical difficulty of CO₂ capture. Also, materials capable of adsorbing such low concentrations of CO₂ often require high temperatures to release it for sequestration, an important part of the cycle that offsets initial low-carbon benefits. NGCC emissions also have a higher concentration of O₂, which has a corrosive effect on adsorbent materials, and both NGCC and coal flue streams are saturated in water, which can both degrade materials and reduce efficiency. Thus, an effective NGCC CO₂-capture material must selectively bind low-concentration CO₂ under humid conditions while being thermally and oxidatively stable.

Image: Single-crystal x-ray diffraction enables the precise determination of the positions of the atoms in metal–organic frameworks (MOFs), highly porous materials capable of soaking up vast quantities of a specific gas molecule, such as CO₂. This structure represents 2-ampd–Zn₂(dobpdc), a MOF with the same structure as 2-ampd–Mg₂(dobpdc), the subject of this study. Light blue, blue, red, gray, and white spheres represent Zn, N, O, C, and H atoms, respectively.

Scientists observe ultrafast birth of free radicals in water

2020/01/092020/01/23

What they learned could lead to a better understanding of how ionizing radiation can damage material systems, including cells.

Understanding how ionizing radiation interacts with water—like in water-cooled nuclear reactors and other water-containing systems—requires glimpsing some of the fastest chemical reactions ever observed.

In a new study conducted at the Department of Energy’s SLAC National Accelerator Laboratory, researchers have witnessed for the first time the ultrafast proton transfer reaction following ionization of liquid water. The findings, published today in Science, are the result of a world-wide collaboration led by scientists at the DOE’s Argonne National Laboratory, Nanyang Technological University, Singapore (NTU Singapore) and the German research center DESY.

The proton transfer reaction is a process of great significance to a wide range of fields, including nuclear engineering, space travel and environmental remediation. This observation was made possible by the availability of ultrafast X-ray free electron laser pulses, and is basically unobservable by other ultrafast methods. While studying the fastest chemical reactions is interesting in its own right, this observation of water also has important practical implications.

>Read more on the LCLS at SLAC website

Image: X-rays capture the ultrafast proton transfer reaction in ionized liquid water, forming the hydroxyl radical (OH) and the hydronium (H3O+) ion. Credit: Argonne National Laboratory

Record-shattering underwater sound

2019/05/162019/05/23

Researchers produced an underwater sound with an intensity that eclipses that of a rocket launch while investigating what happens when they blast tiny jets of water with X-ray laser pulses.

A team of researchers has produced a record-shattering underwater sound with an intensity that eclipses that of a rocket launch. The intensity was equivalent to directing the electrical power of an entire city onto a single square meter, resulting in sound pressures above 270 decibels. The team, which included researchers from the Department of Energy’s SLAC National Accelerator Laboratory, published their findings on April 10 in Physical Review Fluids.
Using the Linac Coherent Light Source (LCLS), SLAC’s X-ray laser, the researchers blasted tiny jets of water with short pulses of powerful X-rays. They learned that when the X-ray laser hit the jet, it vaporized the water around it and produced a shockwave. As this shockwave traveled through the jet, it created copies of itself, which formed a “shockwave train” that alternated between high and low pressures. Once the intensity of underwater sound crosses a certain threshold, the water breaks apart into small vapor-filled bubbles that immediately collapse. The pressure created by the shockwaves was just below this breaking point, suggesting it was at the limit of how loud sound can get underwater.

>Read more on the LCLS at SLAC website

Image: After blasting tiny jets of water with an X-ray laser, researchers watched left- and right-moving trains of shockwaves travel away from microbubble filled regions.
Credit: Claudiu Stan/Rutgers University Newark

Illuminating Water Filtration

2019/03/272019/03/29

Researchers using ultrabright x-rays reveal the molecular structure of membranes used to purify seawater into drinking water.

For the first time, a team of researchers from Stony Brook University and the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have revealed the molecular structure of membranes used in reverse osmosis. The research is reported in a recently published paper in ACS Macro Letters, a journal of the American Chemical Society (ACS).
Reverse osmosis is the leading method of converting brackish water or seawater into potable or drinking water, and it is used to make about 25,000 million gallons of fresh water a day globally according to the International Water Association.
“Most of the earth’s water is in the oceans and only three percent is fresh water, so water purification is an essential tool to satisfy the increasing demand for drinking water,” said Brookhaven Lab senior scientist Benjamin Ocko. “Reverse osmosis is not a new technology; however, the molecular structure of many of the very thin polymer films that serve as the barrier layer in reverse osmosis membranes, despite its importance, was not previously known.”

>Read more on the NSLS-II website

Image: Qinyi Fu, Francisco J. Medellin-Rodriguez, Nisha Verma, and Benjamin Ocko (from left to right) prepare to mount the membrane samples that mimic the membranes used in reverse osmosis for the measurements in the Complex Materials Scattering (CMS) beamline at the National Synchrotron Light Source II (NSLS-II).

HIPPIE provides a closer look at water filtration

2019/03/222019/03/22

Clean fresh water is a scarce resource. Areas of the world suffering from drought have to filter the salt out of seawater to make it drinkable. In other areas, the water may instead have a high content of toxic compounds, such as arsenic.
If you think about a water filter as a kind of strainer with tiny holes through it, you would assume that since it does a pretty good job of filtering out the small ions of normal table salt, sodium, and chloride, from seawater it would work even better for the larger arsenic compounds. This is however not the case when it comes to desalination – the technology for producing fresh water from seawater; quite the opposite actually. While sodium and chloride are removed effectively, other, much larger contaminants pass through the filtration materials that are typically used. That indicates there must be another mechanism at work here.

Scientists develop printable water sensor

2019/03/042019/03/04

X-ray investigation reveals functioning of highly versatile copper-based compound

A new, versatile plastic-composite sensor can detect tiny amounts of water. The 3d printable material, developed by a Spanish-Israeli team of scientists, is cheap, flexible and non-toxic and changes its colour from purple to blue in wet conditions. The researchers lead by Pilar Amo-Ochoa from the Autonomous University of Madrid (UAM) used DESY’s X-ray light source PETRA III to understand the structural changes within the material that are triggered by water and lead to the observed colour change. The development opens the door to the generation of a family of new 3D printable functional materials, as the scientists write in the journal Advanced Functional Materials (early online view).

Image: When dried, for example in a water-free solvent, the sensor material turns purple.
Credit: UAM, Verónica García Vegas

Water is more homogeneous than expected

2019/02/202019/02/21

In order to explain the known anomalies in water, some researchers assume that water consists of a mixture of two phases even under ambient conditions.

However, new X-ray spectroscopic analyses at BESSY II, ESRF and Swiss Light Source show that this is not the case. At room temperature and normal pressure, the water molecules form a fluctuating network with an average of 1.74 ± 2.1% donor and acceptor hydrogen bridge bonds per molecule each, allowing tetrahedral coordination between close neighbours.
Water at ambient conditions is the matrix of life and chemistry and behaves anomalously in many of its properties. Since Wilhelm Conrad Röntgen, two distinct separate phases have been argued to coexist in liquid water, competing with the other view of a single-phase liquid in a fluctuating hydrogen bonding network – the continuous distribution model. Over time, X-ray spectroscopic methods have repeatedly been interpreted in support of Röntgen’s postulate.

Image: Water molecules are excited with X-ray light (blue). From the emitted light (purple) information on H-bonds can be obtained.
Credit: T. Splettstoesser/HZB

A timely solution for the photosynthetic oxygen evolving clock

2019/01/252019/01/31

XFEL Hub collaboration reveals the intermediates of the photosynthetic water oxidation clock

A large international collaborative effort aided by the XFEL Hub at Diamond Light Source has generated the most detailed time-resolved studies to date of a key protein involved in photosynthesis. The pioneering work, recently published in Nature, shows how photosystem II harnesses light energy to produce oxygen – insights that could direct a next generation of photovoltaic cells.
>Read more on the Diamond Light Source website

Image: this figure is issued from a video you can watch here.

Know your ennemy

2018/12/212019/01/08

Light source identifies a key protein interaction during E. coli infection

Escherichia coli is a common source for contaminated water and food products, causing the condition known as gastroenteritis with symptoms that include diarrhea, vomiting, fever, loss of energy, and dehydration. In fact, for children or individuals with weakened immune systems, this bacterial infection in the gut can be life-threatening.

One of the microbes responsible for gastroenteritis, known formally as enteropathogenic E. coli (EPEC), causes infections by directing a pointed, needle-like projection into the human intestinal tract, releasing toxins that make people sick.

“Enteropathogenic E. coli can fire toxic proteins from inside the bacterium right into the cells of your gut lining,” says Dustin Little, a post-doctoral researcher in the Brian Coombes lab at McMaster University’s Department of Biochemistry and Biomedical Sciences.

Image: Dustin Little and Brian Coombes in the lab.
Credit: Dustin Little.

World’s fastest water heater

2018/05/142018/05/22

Scientists explore exotic state of liquid with X-ray laser

Scientists have used a powerful X-ray laser to heat water from room temperature to 100,000 degrees Celsius in less than a tenth of a picosecond (millionth of a millionth of a second). The experimental set-up, that can be seen as the world’s fastest water heater, produced an exotic state of water, from which researchers hope to learn more about the peculiar characteristics of Earth’s most important liquid. The observations also have practical use for the probing biological and many other samples with X-ray lasers. The team of Carl Caleman from the Center for Free-Electron Laser Science (CFEL) at DESY and Uppsala University (Sweden) reports its findings in the journal Proceedings of the National Academy of Sciences (PNAS).

The researchers used the X-ray free-electron laser Linac Coherent Light Source LCLS at the SLAC National Accelerator Laboratory in the U.S. to shoot extremely intense and ultra-short flashes of X-rays at a jet of water. “It is certainly not the usual way to boil your water,” said Caleman. “Normally, when you heat water, the molecules will just be shaken stronger and stronger.” On the molecular level, heat is motion – the hotter, the faster the motion of the molecules. This can be achieved, for example, via heat transfer from a stove, or more directly with microwaves that make the water molecules swing back and forth ever faster in step with the electromagnetic field.

Image: After about 70 femtoseconds (quadrillionths of a second) most water molecules have already split into hydrogen (white) and oxygen (red).
Credit: Carl Caleman, DESY/Uppsala University

Study suggests water may exist in Earth’s lower mantle

2018/03/162018/03/16

Water on Earth runs deep – very deep. The oceans have been measured to a maximum depth of 7 miles, though water is known to exist well below the oceans. Just how deep this hidden water reaches, and how much of it exists, are the subjects of ongoing research.

Now a new study suggests that water may be more common than expected at extreme depths approaching 400 miles and possibly beyond – within Earth’s lower mantle. The study, which appeared March 8 in the journal Science, explored microscopic pockets of a trapped form of crystallized water molecules in a sampling of diamonds from around the world.

Diamond samples from locations in Africa and China were studied through a variety of techniques, including a method using infrared light at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). Researchers used Berkeley Lab’s Advanced Light Source (ALS), and Argonne National Laboratory’s Advanced Photon Source, which are research centers known as synchrotron facilities.

Photo: Oliver Tschauner, professor of research in the Department of Geoscience at the University of Nevada, Las Vegas, holds a diamond sample during a recent round of experiments at Berkeley Lab’s Advanced Light Source.
Credit: Marilyn Chung/Berkeley Lab

Structure and Catalytic Activity of Copper Nanoparticles

2018/01/222018/01/28

Research investigates the addition of ceria on the activity of catalysts for the water-gas shift reaction

Catalysts are substances that promote and accelerate chemical reactions without being consumed during the process and are widely used in industrial processes to produce various chemicals.

Catalysts based on copper nanoparticles dispersed in an oxide support benefit various reactions, such as the synthesis of methanol, the alcohol dehydrogenation, or the water gas shift (WGS) reaction which is one of the main processes for hydrogen production on an industrial scale. In this reaction, carbon monoxide reacts with water to produce carbon dioxide $C O_{2}$ and hydrogen gas $H_{2}$ .

>Read more on the LNLS website

Figure 1: Correlation between the bond length of $C u — O$ and the catalyst turnover frequency (TOF) for the catalysts analyzed under WGS conditions with different proportions of copper and ceria.

Extraterrestrial Oceans

2018/01/092018/01/15

Exploring the solar system does not need spacecraft

One of the amazing things scientists can do at Diamond is to recreate conditions of other parts of the Universe. Recently they used this remarkable ability to peer into the salty waters hidden underneath kilometres of ice on Enceladus, one of Saturn’s moons.

In September, NASA ended the Cassini mission in spectacular fashion, crashing the spacecraft into Saturn. For twenty years, Cassini brought us closer to our gas giant neighbour and its moons. The probe made astonishing discoveries about one of them: Enceladus. This small moon has plumes of gas erupting from its surface, it has a rocky core covered in a thick layer of ice, and in between lies a deep, salty ocean. It is one of the most promising places to look for extraterrestrial life. Enceladus is one of the few places in the Solar System where liquid water is known to exist.

Spacecraft aren’t our only way of exploring the solar system, and Stephen leads a team of experimental astrophysicists based at Diamond and Keele University (UK), who have been recreating the conditions in Enceladus’s salty ocean right here in Harwell. They have been using Diamond’s astoundingly bright light to investigate one of the more mysterious properties of water – its ability to form clathrates when water is cooled under pressure. Clathrates are ice-like structures that behave like tiny cages, and can trap molecules such as carbon dioxide and methane.

Image Credit: LPG-CNRS-U. Nantes/Charles U., Prague.

Researchers explore ways to remove antibiotics polluting lakes and rivers

2017/10/112017/10/16

Pre-treated barley straw is showing promise as an environmentally-friendly material.

Pre-treated barley straw could be used to help soak up certain types of antibiotics polluting waterways. Pharmaceuticals, including antibiotics, are an increasingly common pollutant in water systems, says Catherine Hui Niu, associate professor in the Department of Chemical and Biological Engineering at the University of Saskatchewan.

After pharmaceuticals are used in humans and animals, traces are excreted and end up in sewage and, from there, into the environment. Their presence in waterways has raised concerns about potential risks to human health and ecosystems. To date there has been no effective way to remove them from water sources.

There are some materials that attract pharmaceutical pollutants to them in a process called adsorption, and could hypothetically be used to help remove them from water, says Niu. But their adsorption capacities need to be enhanced to make them useful for large scale clean-up efforts.

>Read More

High-Speed Movie Aids Scientists Who Design Glowing Molecules

2017/09/202017/10/12

A research team captured ultrafast changes in fluorescent proteins between “dark” and “light” states.

The crystal jellyfish swims off the coast of the Pacific Northwest and can illuminate the waters when disturbed. That glow comes from proteins that absorb energy and then release it as bright flashes.

To track many of life’s activities, biologists took a cue from this same jellyfish.

Scientists collected one of the proteins found in the sea creatures, green fluorescent protein (GFP), and engineered a molecular light switch that would glow or remain dark depending on specific experimental conditions. The glowing labels are attached to molecules in living cells so researchers can highlight them during imaging experiments. They use these fluorescent markers to understand how a cell responds to changes in its environment, identify which molecules interact within a cell and track the effects of genetic mutations.