It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Sunday, November 05, 2023
POSTMODERN ALCHEMY
Charged “molecular beasts” the basis for new compounds
Researchers at Leipzig University use “aggressive” fragments of molecular ions for chemical synthesis
Developing new ways to break and reform chemical bonds is one of the main tasks of basic chemical research. “When a bond in a charged molecule is broken, the result is often a chemically ‘aggressive’ fragment, which we call a reactive fragment. These fragments are difficult to control using established methods of chemical synthesis. You can think of them as untamed beasts that attack anything in their path. In a mass spectrometer, there are many ways to break certain bonds and generate fragments,” says Dr Warneke, describing the processes in mass spectrometers. According to him, the “beasts” are kept under special conditions because there is a vacuum inside the mass spectrometer. This means that there is nothing for them to attack, thus preventing uncontrolled chemical reactions. “If we then offer a certain molecule, for example nitrogen, which is normally unreactive and doesn’t bind, the beast is satisfied with it because it has no other choice,” he says. In this way, molecules that are very difficult to bind, such as nitrogen, can be easily incorporated into a new substance,” Warneke continues.
In the past, the research team has used this approach to bring reactive fragments into very unusual reactions, for example, with noble gases, which are the most difficult of all chemical elements to bind. “The basic strategy of controlling chemical beasts in mass spectrometers is not new,” says Warneke. It has been used for decades to analyse the properties of reactive fragments. However, the new compounds found in this way could not be further used. Mass spectrometers show what is happening inside them, but the new substances are only produced in tiny quantities and cannot usually be extracted. They are often simply destroyed when the signal used for analyses is generated.
This is why researchers usually come away from experiments with mass spectrometers with “great knowledge” but “empty hands”. “They have the beast under control. Exactly what they were hoping for happens, they observe the new molecule with potentially fascinating properties, and then it’s gone,” says Warneke, describing chemical experiments in conventional mass spectrometers. The new publication could fundamentally change this view of chemical reactions in mass spectrometers. The research team produced a new substance from an aggressive fragment and unreactive nitrogen and collected it with preparative mass spectrometers in sufficient quantities so that it could be seen with the naked eye, handled and further experimented with.
The amount of substance produced by this method will remain limited to thin film technology applications for some time to come. However, preparative mass spectrometry could soon open up completely new possibilities for these applications, for example, in the production of microchips, solar cells or biologically active coatings. The junior research group has now reached an important milestone in its project, which has been funded by the Volkswagen Foundation’s Freigeist Fellowship since 2020.
MAX PLANCK INSTITUTE FOR THE STRUCTURE AND DYNAMICS OF MATTER
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INSIDE THE OPTICAL CAVITY, LIGHT PARTICLES EMERGE AND DISAPPEAR. THESE FLUCTUATIONS CAN CHANGE THE MAGNETIC ORDER OF Α-RUCL3 FROM A ZIGZAG ANTIFERROMAGNET INTO A FERROMAGNET.
Researchers in Germany and the USA have produced the first theoretical demonstration that the magnetic state of an atomically thin material, α-RuCl3, can be controlled solely by placing it into an optical cavity. Crucially, the cavity vacuum fluctuations alone are sufficient to change the material’s magnetic order from a zigzag antiferromagnet into a ferromagnet. The team’s work has been published in npj Computational Materials.
A recent theme in material physics research has been the use of intense laser light to modify the properties of magnetic materials. By carefully engineering the laser light’s properties, researchers have been able to drastically modify the electrical conductivity and optical properties of different materials. However, this requires continuous stimulation by high-intensity lasers and is associated with some practical problems, mainly that it is difficult to stop the material from heating up. Researchers are therefore looking for ways to gain similar control over materials using light, but without employing intense lasers.
Now theoreticians at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg, Germany, Stanford University and the University of Pennsylvania (both in the USA) have come up with a fundamentally different approach to change a real material’s magnetic properties in a cavity – without the use of any laser light. Their collaboration shows that the cavity alone is enough to turn the zigzag antiferromagnet α-RuCl3 into a ferromagnet.
Crucially, the team demonstrates that even in an apparently dark cavity, α-RuCl3 senses modifications of the electromagnetic environment and changes its magnetic state accordingly. This is a purely quantum mechanical effect, arising from the fact that within quantum theory the empty cavity (technically called the vacuum state) is never really empty. Instead, the light field fluctuates so that light particles pop in and out of existence which, in turn, affects the properties of the material.
“The optical cavity confines the electromagnetic field to a very small volume, thereby enhancing the effective coupling between the light and the material,” explains lead author Emil Viñas Boström, a postdoctoral researcher in the MPSD Theory Group. “Our results show that carefully engineering the vacuum fluctuations of the cavity electric field can lead to drastic changes in a material’s magnetic properties.” As no light excitation is needed, the approach in principle circumvents the problems associated with continuous laser driving.
This is the first work demonstrating such cavity control over magnetism in a real material, and follows previous investigations into cavity control of ferroelectric and superconducting materials. The researchers hope that designing specific cavities will help them realize new and elusive phases of matter, and to better understand the delicate interplay between light and matter.
A NEWLY DEVELOPED CERAMIC FILLER MAY HELP ALLEVIATE LIMITATIONS OF COMPOSITE SOLID-STATE ELECTROLYTES. THE FILLER NOT ONLY MITIGATES INTERFACE BARRIERS BETWEEN THE COMPOSITE COMPONENTS, BUT IT ALSO PROVIDES AN ADDITIONAL LITHIUM-ION TRANSPORT PATHWAY, INCREASING THE NUMBER OF IONS AND THE SPEED WITH WHICH THEY MOVE THROUGH THE ELECTROLYTE.
CREDIT: ENERGY MATERIALS AND DEVICES, TSINGHUA UNIVERSITY PRESS
Lithium-ion batteries powered the device on which these words appear. From phones and laptops to electric vehicles, lithium-ion batteries are critical to the technology of the modern world — but they can also explode. Comprising negatively and positively charged electrodes and an electrolyte to transport ions across the divide, lithium-ion batteries are only as good as the limitations of their components. Liquid electrolytes are potentially volatile at high temperatures, and their efficiency can be limited by nonuniformity and instabilities in the other components.
Researchers are working toward developing safer, more efficient batteries with solid electrolytes, a significant change over the liquid version that currently transports ions in most commercially available batteries now. The challenge is that each solid-state material has as many drawbacks as advantages, according to a team based at the Shenzhen All-Solid-State Lithium Battery Electrolyte Engineering Research Center in Tsinghua Shenzhen International Graduate School’s Institute of Materials Research.
To solve this conundrum, the researchers combined two of the prime solid-state candidates — ceramic and polymer — into a new composite electrolyte.
“Composite solid-state electrolytes have received significant attention due to their combined advantages as inorganic and polymer electrolytes,” said co-first author Yu Yuan, who is also affiliated with Tsinghua Shenzhen International Graduate School. “However, conventional inorganic ceramic fillers offer limited ion conductivity enhancement for composite solid-state electrolytes due to the space-charge layer between the polymer matrix and ceramic phase.”
Inorganic ceramic electrolytes offer high conductivity, but they develop resistance when faced with another solid and are complicated to synthesize. Polymer electrolytes are easier to produce, more flexible and work better with electrodes, but their conductivity at room temperature is too low for commercial application. According to Yuan, combining the two should produce a highly conductive, flexible electrolyte that is easier to synthesize. In reality, however, when mixed, the composite solid-state electrolytes have a separation — called a space-charge layer — between their constituent parts that limits their conductivity.
To correct this, the researchers used lithium tantalate, which has a crystalline structure that lends itself to unique optical and electrical properties, as a functional filler to mitigate the space-charge layer. The ceramic ion conductor material is ferroelectric, mean it can reverse electric charge when a current is applied.
“Not only does the filler alleviate the space-charge layer, but it also provides an extra lithium-ion transport pathway,” said co-first author Likun Chen, who is also affiliated with Tsinghua Shenzhen International Graduate School.
The researchers experimentally demonstrated that the lithium tantalate filler eases the bottleneck for lithium-ion transport across the polymer-ceramic interface, resulting in lithium ions moving in both increased numbers and speed through the electrolyte.
The result, the researchers said, is an electrolyte with high conductivity and a long-cycling life — referring to how often the ions can be transported across the battery in charging and discharging cycles — even at low temperatures.
“This work proposes a novel strategy for designing integrated ceramic fillers with ferroelectric and ion-conductive properties to achieve high-throughput lithium-ion transport of composite-solid electrolytes for advances solid-state lithium metal batteries,” Yuan said. “Our approach sheds light on the design of functional ceramic fillers for composite solid-state electrolytes to effectively enhance ion conductivity and battery performance.”
Other co-authors include Yuhang Li, Xufei An, Jianshuai Lv, Shaoke Guo, Xing Cheng, Yang Zhao, Ming Liu, Yan-Bing He and Feiyu Kang. Li, An, Lv, Guo, Cheng, Zhao and Kang are also affiliated with Tsinghua Shenzhen International Graduate School.
The National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Shenzhen Outstanding Talents Training Fund, All-Solid-State Lithium Battery Electrolyte Engineering Research Center and Shenzheng Technical Plan Project supported this research.
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Networked intelligent devices and sensors can improve the energy efficiency of consumer products and buildings by monitoring their consumption in real time. Miniature devices like these being developed under the concept of the Internet of Things require energy sources that are as compact as possible in order to function autonomously. Monolithically integrated batteries that simultaneously generate, convert, and store energy in a single system could be used for this purpose. A team of scientists at the University of Freiburg’s Cluster of Excellence Living, Adaptive, and Energy-Autonomous Materials Systems (livMatS) has developed a monolithically integrated photo battery consisting of an organic polymer-based battery and a multi-junction organic solar cell. The battery, presented by Rodrigo Delgado Andrés andDr. Uli Würfel, University Freiburg, and Robin Wessling and Prof. Dr. Birgit Esser, University of Ulm, is the first monolithically integrated photo battery made of organic materials to achieve a discharge potential of 3.6 volts. It is thus among the first systems of this kind capable of powering miniature devices. The team published their results in the journal Energy & Environmental Science.
Combination of a multi-junction solar cell and a dual-ion battery
The researchers developed a scalable method for the photo battery which allows them to manufacture organic solar cells out of five active layers. “The system achieves relatively high voltages of 4.2 volts with this solar cell,” explains Wessling. The team combined this multi-junction solar cell with a so-called dual-ion battery, which is capable of being charged at high currents, unlike the cathodes of conventional lithium batteries. With careful control of illumination intensity and discharge rates, a photo battery constructed in this way is capable of rapid charging in less than 15 minutes at discharge capacities of up to 22 milliampere hours per gram (mAh g-1). In combination with the averaged discharge potential of 3.6 volts, the devices can provide an energy density of 69 milliwatt hours per gram (mWh g-1) and a power density of 95 milliwatts per gram (mW g-1). “Our system thus lays the foundation for more in-depth research and further developments in the area of organic photo batteries,” says Wessling.
About the Cluster of Excellence livMatS
The vision of the Cluster of Excellence Living, Adaptive, and Energy-Autonomous Materials Systems (livMatS) is to combine the best of both worlds – nature and technology. livMatS develops lifelike materials systems inspired by nature. These systems adapt autonomously to their environment, harvest clean energy from their surroundings, and are insensitive to or able to recover from damage.
Original publication:Andrés, R. D., Wessling, R., Büttner, J., Pap, L., Fischer, A., Esser, B., & Würfel, U. (2023). Organic photo-battery with high operating voltage using a multi-junction organic solar cell and an organic redox-polymer-based battery. Energy & Environmental Science. DOI: 10.1039/d3ee01822a
Prof. Dr. Birgit Esser heads the Chair in Organic Chemistry at the Institute of Organic Chemistry II and Advanced Materials at the University of Ulm. She is a member of the Clusters of Excellence Post Lithium Storage (POLiS) at Ulm University and Living, Adaptive, and Energy-Autonomous Materials Systems (livMatS) at the University of Freiburg.
Dr. Uli Würfel leads the group “Organic and Perovskite Solar Cells” at FMF and FIT at the University of Freiburg and is a member of the Cluster of Excellence livMatS at the University of Freiburg. In addition, he is head of the research topic “Organic and Perovskite Photovoltaics” at the Fraunhofer Institute for Solar Energy Systems (ISE).
Rodrigo Delgado Andrés is pursuing a doctorate under Dr. Uli Würfel at the Cluster of Excellence livMatS.
Robin Wessling is pursuing a doctorate under Prof. Dr. Birgit Esser at the Cluster of Excellence livMatS.
The study was funded by the German Research Foundation (DFG) (livMatS – EXC 2193).
UNIVERSITY OF VIRGINIA SCHOOL OF ENGINEERING AND APPLIED SCIENCE
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ASHISH VENKAT, AN ASSISTANT PROFESSOR OF COMPUTER SCIENCE AND CYBERSECURITY EXPERT, HAS RECEIVED AN NSF CAREER AWARD TO DEVELOP A HARDWARE AND SOFTWARE SYSTEM ENABLING RAPID, SECURE MITIGATION OF CYBERATTACKS, INCLUDING ZERO-DAY EVENTS.
They’re called “zero-day attacks” and they’re what keeps cybersecurity experts like Ashish Venkat up at night.
These are the cyberattacks that disable large-scale computer programs, catching their victims off guard. In recent years, they’ve been happening more often and have become increasingly difficult to fix.
“The term zero-day attack means that a developer didn’t know about the flaw beforehand giving them zero days to fix it,” said Venkat, the William Wulf Career Enhancement Assistant Professor in the Department of Computer Science at the University of Virginia School of Engineering and Applied Science. “A new attack is discovered every 17 days and it takes an average of 15 days to patch these vulnerabilities.”
Vulnerabilities Are Costly to Patch
Companies large and small as well as individuals spend far too much time and money fixing these flaws. And, Venkat said, they end up introducing more vulnerabilities while they’re trying to patch old ones.
Venkat recently received a CAREER Award from the National Science Foundation with the goal of solving these urgent issues. It’s one of the NSF’s most prestigious awards in support of early-career faculty who have the potential to lead advances from within their field. Venkat joined the University of Virginia in 2018 shortly after obtaining his Ph.D. from the University of California San Diego.
His fix could both reduce attack response time and protect programs from other attacks while an issue is being mitigated. Venkat’s team will develop a “decoupled” security response, which means designing a holistic security-centric hardware software stack that allows technicians to go into a computer system to fix a vulnerability through a separate security entrance, on demand and in the field.
Innovation Could Lead to Faster Response Time
“As long as computer systems have flaws, cybercriminals will try to exploit them,” said Sandhya Dwarkadas, the Walter N. Munster Professor and chair of computer science at UVA. “Ashish’s proposed stack is an innovative use of integrated hardware and software components dedicated to security functions. His project addresses a critical need and I look forward to following his progress.”
Venkat’s system could help him stop emerging zero-day cyberattacks within 24 to 48 hours, 13 days faster than the average response time today. His solution also could reduce the significant time and dollar costs of frequent patching, redeployment and hardware upgrades.
When cybersecurity experts are trying to reach the site of a problem, they often leave doors open behind them on the way. Venkat’s decoupled approach will create a security tunnel running through the system so that in the midst of a cyberattack, technicians can rapidly locate the vulnerable component and enforce an appropriate security policy to fix it without opening new entry points for bad actors.
“The decoupled hardware software stack allows security policies to be defined in software, but enforced in hardware, enabling versatility, flexibility and efficiency at the same time,” Venkat said. “In fact, the project’s second objective is to design new computer hardware to enforce emerging cybersecurity measures against a range of attacks without compromising efficiency.”
The third objective is to enable the new hardware to continuously track the flow of information for precise enforcement of software-defined security policies.
Building a Cyber Workforce for the Future
The CAREER Award, which totals over half a million dollars, also has an educational component. As computer software gets more complicated and is made up of increasingly specialized components, it’s getting harder to train the next generation of cyberexperts — both technicians to work on the systems and researchers to assess impending threats.
The goal, Venkat said, is to improve cybersecurity curricula and awareness for high school, vocational and college students. As part of the project, his team will establish a mentorship program for undergraduate students, including groups traditionally underrepresented in engineering and computer science, to help build a cybersecurity workforce for the future.
Finally, Venkat isn’t limiting his approach to cybersecurity defense — he’s also using offensive tactics, known as ethical or “white hat” hacking. The practice uses a team of highly trained ethical hackers to examine a system before a hack occurs.
“You teach students how to ethically hack a system with the goal of better understanding potential vulnerabilities and to improve the security of modern systems,” Venkat said.
His research group earned significant press attention in 2021 for discovering a security vulnerability that impacted millions of computers with Intel and AMD processors. Subsequent efforts to discover vulnerabilities includes their work on hardware Trojan attacks, which has been nominated for a best paper award at DATE 2023, the Design, Automation and Test in Europe conference.
Real-World Implications for Real People
Venkat is also concerned about building protections against global threats such as the WannaCry ransomware attack in 2017. Exploiting a vulnerability in the Microsoft Windows operating system, WannaCry spread to more than 200,000 computers in 150 countries within days — harming large and small organizations, including hospitals. The malware, which can self-propagate across networks, encrypted the computers’ data and demanded cryptocurrency payments in exchange for returning control of the computers to their owners.
“These attacks can go after anyone, not just huge corporations,” Venkat said. “They can put mom-and-pop companies out of business, they can impact your grandmother. “When companies aren’t able to invest in cybersecurity, sometimes they just go out of business because their insurance premiums become so inflated.”
Venkat’s goal is to create a set of cybersecurity fixes that are economical for individuals and small businesses alike.
“There’s an urgent need for systems that are designed to be secure from inception and to tighten security around already deployed systems vulnerable to attack,” he said. “I’m passionate about this work because, in the end, it’s people who are harmed by zero-day and other cyberattacks.”
H2
What is ‘white hydrogen’? The pros and cons of Europe’s latest clean energy source
Angela Symons Sun, 5 November 2023
Hydrogen has been touted as the ‘fuel of the future’. It only emits heat and water when it burns, making it an appealing alternative to fossil fuels.
But the majority of hydrogen production currently relies on gas or coal, in processes that emit a lot of CO2.
‘Green’ hydrogen, which is made using renewable energy, offers a promising - but expensive - alternative. So what if there was a way to cut out these production processes altogether?
Earth holds vast supplies of natural hydrogen that could be extracted from the ground.
A huge discovery of this so-called ‘white’ hydrogen in France earlier this year sparked excitement that it could become a clean, cheap and renewable energy source.
Switzerland soon joined the search, finding natural hydrogen in the Graubünden canton in spring. In summer, the country began probing rocks in Valais for further deposits.
Could white hydrogen hold the key to safe and clean energy, and why is it only just being explored?
What is white hydrogen?
Hydrogen is the most abundant chemical element on Earth and occurs naturally in everything from water to plants.
Until recently, however, significant quantities of hydrogen gas in its pure form were not thought to be present within the earth.
An accidental discovery was made in Mali in 2012. A borehole drilled for a well decades earlier was found to be emitting almost pure natural hydrogen.
Since then, geologists have increasingly been experimenting with extracting supplies of this natural gas - thought to form through water-mineral reactions - from beneath the earth’s surface.
Unlike fossil fuel stores, which take millions of years to form, natural or ‘white’ hydrogen is continuously replenished.
It isn’t yet clear exactly how white hydrogen deposits form, and whether they are commercially exploitable.
Startups and scientists are exploring this possibility - with some promising results.
“The earth has many locations where the right conditions co-exist to naturally produce and accumulate hydrogen, which can then be extracted for societal use,” Dr Michael Webber, a professor in energy resources at the University of Texas, Austin, USA, tells Euronews Green.
“The good news is that by letting the earth do the work for us, this source of hydrogen is likely much cleaner to produce than current methods of gasifying coal, reforming methane, or electrolysing water.”
Although most natural hydrogen is likely to be found in unreachable offshore locations, deposits have been discovered in Australia, eastern Europe, France, Oman, Spain and the US, as well as in Mali, West Africa.
In May, a large deposit of natural hydrogen was accidentally discovered in the Lorraine region of France. A research team from the University of Lorraine’s GeoRessources Lab, France’s National Centre for Scientific Research (CNRS) and energy producer La Française de l'Energie found it while testing methane levels in the soil.
They are currently drilling deeper to find out exactly how much hydrogen there is, but estimate that there could be around 46 million tonnes - the equivalent of more than half of the world’s current annual production of grey hydrogen - according to CNRS.
Meanwhile in northeast Spain, exploration company Helios Aragón says it has located a reservoir of over one million tonnes of hydrogen, which it aims to start drilling in 2024.
It shows promise as a cheap alternative to green hydrogen, which currently costs roughly €5 per kilogram. White hydrogen costs just €0.50 per kilogram, news and research outlet Science reports. What are the problems with hydrogen energy?
White hydrogen may not be a silver bullet for the energy crisis, however.
Some scientists say the lack of data on hydrogen leaks and the potential harm they could cause is an issue for the emerging industry.
If hydrogen seeps into the atmosphere, it can reduce the concentration of molecules that destroy the greenhouse gases there, counteracting its environmental benefits.
With a lack of technology to monitor hydrogen leaks, this could be a major blind spot.
“As with other sources of hydrogen, [natural hydrogen] needs to be handled with care to reduce safety risks and avoid leaks,” says Dr Webber.
But it may not be as significant an environmental risk as some believe.
“Our research at UT Austin, which was presented [on Wednesday] at the ASME IMECE conference in New Orleans, concludes that the indirect global warming impact of fugitive hydrogen emissions is actually quite small compared to other life cycle greenhouse gas impacts, so the greenhouse risks from unwanted hydrogen leaks is minor.”
Leaks aren’t the only concern when transporting hydrogen, though. It takes up a lot of space in gas form and requires a temperature of -253°C to be liquified, which could be prohibitively expensive.
There is also a lack of pipelines and distribution systems for hydrogen. The fossil fuel industry hopes that it could eventually move through existing infrastructure, such as gas pipelines. However, scientists say that hydrogen can corrode metal pipes and lead to cracking.
Not only are hydrogen molecules much smaller and lighter than those in methane, making them harder to contain, but they are also far more explosive than natural gas - raising safety concerns.
These are some of the reasons heat pumps and battery powered EVs won out over hydrogen-based alternatives, according to Science.
The fuel could be better suited to heavy-duty vehicles which can’t easily use batteries, such as trucks, ships and planes, as well as the steel industry and chemical processes like fertiliser production.
New approach to water electrolysis for green hydrogen
Originally, the term "Sherpa" denoted a hill-tribe of Tibetan descent, but it has since become synonymous with guides on Mount Everest, the world's highest and most rugged mountain. Much like these Sherpas, research into the demanding task of developing catalysts for hydrogen production is making substantial progress and has earned recognition as the featured cover article in a prominent international journal.
Professor Yong-Tae Kim from the Department of Materials Science and Engineering and the Graduate Institute of Ferrous & Eco Materials Technology, and Kyu-Su Kim, a doctoral student from the Department of Materials Science and Engineering at Pohang University of Science and Technology (POSTECH), collaborated on a research project that offers a promising direction for the future development of catalysts for water electrolysis. Their study has garnered considerable academic attention and was showcased as the cover article in ACS Catalysis, an international journal in the field of chemistry.
Water electrolysis, a method for producing hydrogen from the abundant resource of water, emerges as an environmentally friendly technology that produces no carbon dioxide emissions. However, this process faces limitations due to its reliance on precious metal catalysts such as iridium (Ir), rendering it economically unfeasible. Researchers are actively exploring the development of catalysts in the form of metal alloys to address this challenge.
In the field of water electrolysis catalysis research, the primary catalysts under scrutiny are iridium, ruthenium (Ru), and osmium (Os). Iridium, despite its high stability, exhibits low activity and comes at a steep price. Conversely, ruthenium displays commendable activity and is a more cost-effective option compared to iridium, although it lacks the same level of stability. Osmium, on the other hand, readily dissolves under various electrochemical conditions, leading to the formation of nanostructures with an expanded electrochemical active surface area, thereby enhancing geometrical activity.
Initially, the research team developed catalysts using both iridium and ruthenium. By combining these metals, they successfully preserved the excellent attributes of each, resulting in catalysts that demonstrated improvements in both activity and stability. Catalysts incorporating osmium exhibited high activity due to the expanded electrochemical active surface area achieved through nanostructure formation. These catalysts retained the advantageous properties of iridium and ruthenium.
Subsequently, the team expanded their experimentation to include all three metals. The results showed a moderate increase in activity, but the dissolution of osmium had a detrimental effect, significantly compromising the structural integrity of iridium and ruthenium. In this series, the agglomeration and corrosion of nanostructures were accelerated, leading to a decline in the balance of catalytic performance.
Based on these findings, the research team has proposed several avenues for further catalyst research. First and foremost, they stress the need for a metric that can simultaneously evaluate both activity and stability. This metric, known as the activity-stability factor, was initially introduced by Kim's research group in an international journal in 2017.
Additionally, the team advocates for the retention of superior catalyst properties even after the formation of nanostructures, in order to enhance the electrochemical active surface area of the electrocatalyst. They also highlight the importance of carefully selecting candidate materials that can effectively synergize when alloyed with other metals. The essence of this study lies not in presenting specific outcomes like the development of new catalysts, but rather in offering essential considerations for catalyst design.
Professor Yong-Tae Kim, who spearheaded the research, remarked, "This research marks the beginning of our journey, not the conclusion." He shared his vision by stating, "We are dedicated to the continuous development of efficient water electrolysis catalysts based on the insights gained from this research."
The study received support from the Future Materials Discovery Program of the National Research Foundation of Korea.
