Latest Research News
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Developing nanocatalysts to overcome limitations of water electrolysis technology
- Developing nanocatalysts that do not degrade at high temperatures above 600 degrees Celsius - More than doubling green hydrogen production with high-temperature water electrolysis cells Green hydrogen can be produced through water electrolysis technology, which uses renewable energy to split water into hydrogen and oxygen without emitting carbon dioxide. However, the production cost of green hydrogen is currently around $5 per kilogram, which is two to three times higher than gray hydrogen obtained from natural gas. For the practical use of green hydroten, the innovation in water electrolysis technology is required for the realization of hydrogen economy, especially for Korea where the utilization of renewable energy is limited owing to geographical reasons. Dr. Kyung Joong Yoon’s research team at the Energy Materials Research Center of the Korea Institute of Science and Technology (KIST) has developed a nanocatalyst for high-temperature water electrolysis that can retain a high current density of more than 1A/cm2 for a long time at temperatures above 600 degrees. While the degradation mechanisms of nanomaterials at high temperatures have been elusive thus far, the team identified the fundamental reasons of abnormal behavior of nanomateirals and successfully resolved issues, eventually improving performance and stability in realistic water electrolysis cells. The electrolysis technology can be classified into low- and high-temperature electrolysis. While low-temperature electrolysis operating at temperatures below 100 degrees Celsius has long been developed and is technologically more mature, high-temperature electrolysis operating above 600 degrees Celsius offers higher efficiency and is considered as a next-generation technology with a strong potential for further cost-down. However, its commercialization has been hindered by the lack of thermal stability and insufficient lifetime owing to high-temperature degradation, such as corrosion and structural deformation. In particular, nanocatalysts, which are widely used to improve the performance of low-temperature water electrolyzers, quickly deteriorate at high operating temperatures, making it difficult to effectively use them for high-temperature water electrolysis. To overcome this limitation, the team developed a new nanocatalyst synthetic techniques that suppresses the formation of harmful compounds causing high temperature degradation. By systematically analyzing the nanoscale phenomena using transmission electron microscopy, the researchers identified specific substances causing severe structural alterations, such as strontium carbonate and cobalt oxide and successfully removed them to achieve highly stable nanocatalysts in terms of chemical and physical properties. When the team applied the nanocatalyst to a high-temperature water electrolysis cell, it more than doubled hydrogen production rate and operated for more than 400 hours at 650 degrees without degradation. This technique was also sucessfully applied to a practical large-area water electrolysis cell, confirming its strong potential for scale-up and commercial use. "Our newly developed nanomaterials achieved both high performance ans stability for high-temperature water electrolysis technology, and it can contribute to lower the production cost of green hydrogen, making it economically competitive with gray hydrogen in the future," said Dr. Kyungjoong Yoon of KIST. "For commercialization, we plan to develop automated processing techniques for mass production in cooperation with industry cell manufacturers." [Figure 1] Manufacturing process and evaluation results of high temperature water electrolysis cell with nanomaterials ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ This research was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) through the KIST Major Project and Climate Change Response Technology Development Project (2020M1A2A2080862), and the results were published in the latest issue of the Chemical Engineering Journal (IF 15.1, top 3.2% in JCR), an international journal in the field of chemical engineering. Journal : Chemical Engineering Journal Title : In situ synthesis of extremely small, thermally stable perovskite nanocatalysts for high-temperature electrochemical energy devices Publication Date : 2023.10.24. DOI : https://doi.org/10.1016/j.cej.2023.146924
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- WriterDr.Yoon, Kyung Joong
- 작성일2024.01.09
- Views1125
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Artificial intelligence lowers the barrier to ultrasound brain disease treatment
- Developing real-time focused ultrasound simulation technology using generative AI models - Expected to improve the accuracy and safety of brain disease treatment with focused ultrasound Focused ultrasound technology is a non-invasive treatment method that focuses ultrasound energy on a few millimeters of the brain, including deep regions, to treat neurological disorders without opening the skull. It has been applied to the treatment of various intractable brain diseases such as depression and Alzheimer's disease because it minimizes the impact on the surrounding healthy tissue and reduces side effects such as complications and infections. However, its use has been limited so far because it is difficult to reflect the distortion of ultrasound waves caused by the different shapes of the skulls of different patients in real-time. A research team led by Dr. Kim, Hyungmin of the Bionics Research Center at the Korea Institute of Science and Technology (KIST) has developed a real-time acoustic simulation technology based on generative AI to predict and correct the distortion of the ultrasound focus position caused by the skull in real-time during focused ultrasound therapy. Until now, the clinical applicability of AI simulation models in the field of non-invasive focused ultrasound therapy technology has not been validated. To predict the location of the invisible acoustic focus, navigation systems based on medical images taken before treatment are currently utilized, which provide information about the relative position of the patient and the ultrasound transducer. However, they are limited by their inability to account for the distortion of ultrasound waves caused by the skull, and while various simulation techniques have been used to compensate for this, they still require significant computational time, making them difficult to apply in actual clinical practice. The research team developed a real-time focused ultrasound simulation technology through an artificial intelligence model based on a generative adversarial neural network (GAN), a deep learning model widely used for image generation in the medical field. The technology reduces the update time of three-dimensional simulation information reflecting changes in ultrasound acoustic waves from 14 s to 0.1 s, while showing an average maximum acoustic pressure error of less than 7% and a focal position error of less than 6mm, both of which are within the error range of existing simulation technologies, increasing the possibility of clinical application. The research team also developed a medical image-based navigation system to verify the performance of the developed technology in order to rapidly deploy it to real-world clinical practice. The system can provide real-time acoustic simulations at the rate of 5 Hz depending on the position of the ultrasound transducer, and succeeded in predicting the position of the ultrasound energy and focus within the skull in real-time during focused ultrasound therapy. Previously, due to the long calculation time, the ultrasound transducer had to be precisely positioned in a pre-planned location to utilize the simulation results. However, with the newly developed simulation-guided navigation system, it is now possible to adjust the ultrasound focus based on the acoustic simulation results obtained in real-time. In the future, it is expected to improve the accuracy of focused ultrasound and provide safe treatment for patients by being able to quickly respond to unexpected situations that may occur during the treatment process. "As the accuracy and safety of focused ultrasound brain disease treatment has been improved through this research, more clinical applications will emerge," said Dr. Kim, Hyungmin of KIST. "For practical use, we plan to verify the system by diversifying the ultrasound sonication environment, such as multi-array ultrasound transducers." [Figure 1] Simulation-Guided Navigation Systems [Figure 2] Clinical Application Examples for Simulation-Guided Navigation ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ This research was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) under the Creative Convergence Research Project (CAP-18014-000) of the National Research Council of Korea. The research results were published on October 14 in the top international journal NeuroImage (top 3.6% in JCR). Journal : NeuroImage Title : Real-Time Acoustic Simulation Framework for tFUS: A Feasibility Study Using Navigation System Publication Date : 2023.10.14. DOI : https://doi.org/10.1016/j.neuroimage.2023.120411
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- WriterDr. Kim, Hyungmin
- 작성일2024.01.09
- Views1108
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Investigation of degradation mechanism for all-solid-state batteries takes another step toward commercialization
- New findings reveal how degradation of all-solid-state batteries occurs at the cathode under low-pressure operation - Clues to accelerate commercialization of all-solid-state batteries Often referred to as the ‘dream batteries’, all-solid-state batteries are the next generation of batteries that many battery manufacturers are competing to bring to market. Unlike lithium-ion batteries, which use a liquid electrolyte, all components, including the electrolyte, anode, and cathode, are solid, reducing the risk of explosion, and are in high demand in markets ranging from automobiles to energy storage systems (ESS). However, devices that maintain the high pressure (tens of MPa) required for stable operation of all-solid-state batteries have problems that reduce the battery performance, such as energy density and capacity, and must be solved for commercialization. Dr. Hun-Gi Jung and his team at the Energy Storage Research Center at the Korea Institute of Science and Technology (KIST) have newly identified degradation factors that cause rapid capacity degradation and shortened lifespan when operating all-solid-state batteries at pressures similar to those of lithium-ion batteries. Unlike previous studies, the researchers confirmed for the first time that degradation can occur inside the cathode as well as outside, showing that all-solid-state batteries can be operated reliably even in low-pressure environments in the future. [Figure 1] Comparison of cathode volume changes in all-solid-state cells under low-pressure operated In all-solid-state batteries, the cathode and anode have a volume change during repeated charging and discharging, resulting in interfacial degradation such as side reaction and contact loss between active materials and solid electrolytes, which increase the interfacial resistance and worsen cell performance. To solve this problem, external devices are used to maintain high pressure, but this has the disadvantage of reducing energy density as the weight and volume of the battery increase. Recently, research is being conducted on the inside of the all-solid-state cell to maintain the performance of the cell even in low-pressure environments. [Figure 2] Schematic image of cathode degradation in all-solid-state battery under low-pressure operation The research team analyzed the cause of performance degradation by repeatedly operating a coin-type all-solid-state battery with a sulfide-based solid electrolyte in a low-pressure environment of 0.3 MPa, similar to that of a coin-type Li-ion battery. After 50 charge-discharge cycles, the NCM cathode layer had expanded in volume by about two times, and cross-sectional image analysis confirmed that severe cracks had developed between the cathode active material and the solid electrolyte. This newly revealed that in addition to the interfacial contact loss, cracking of the cathode material and irreversible cathode phase transformation are the causes of degradation in low-pressure operation. Furthermore, after replacing the lithium in the cathode with an isotope (6Li) to distinguish it from the lithium present in the solid electrolyte, the team used time-of-flight secondary ion mass spectrometry (TOF-SIMS) to identify for the first time the mechanism by which lithium consumption in the cathode contributes to the overall cell capacity reduction. During repeated charge-discharge cycles, sulfur, a decomposed product of the solid electrolyte, infused the cracks in the cathode material to form lithium sulfide, a byproduct that is non-conductive. This depleted the active lithium ions and promoted cathode phase transformation, reducing the capacity of the all-solid-state batteries. [Figure 3] The front cover image By clearly identifying the cause of the degradation of all-solid-state batteries in low-pressure operating environments, these analytical methods provide a clue to solving the problem of poor cycling characteristics compared to conventional lithium-ion batteries. If this problem is solved, it is expected that the economics of all-solid-state batteries can be secured by eliminating external auxiliary devices, which have been a major cause of rising production costs. "For the commercialization of all-solid-state batteries, it is essential to develop new cathode and anode materials that can be operated in a pressure-free or low-pressure environment rather than the current pressurized environment," said Dr. Hun-Gi Jung of KIST. "When applying low-pressure-working all-solid-state batteries to medium and large-scale applications such as electric vehicles, it will be expected to make full use of established lithium-ion battery manufacturing facilities." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ This research was supported by the Korea Institute of Science and Technology institutional program funded by the Ministry of Science and ICT of Korea (Minister Lee Jong-ho), by the Development Program of Core Industrial Technology funded by the Ministry of Trade, Industry and Energy (Minister Bang, Moon Kyu), and by the Technology Development Program to Solve Climate Changes funded by the National Research Foundation (President Lee, Kwang-bok). The research results were published as a front cover article in the latest issue of Advanced Energy Materials (IF 27.8, top 2.5% in JCR), an international journal in the field of energy materials. Journal : Advanced Energy Materials Title : New Consideration of Degradation Accelerating of All-Solid-State Batteries under a Low-Pressure Condition Publication Date : 27-Oct-2023 DOI : https://doi.org/10.1002/aenm.202301220
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- WriterDr. Jung, Hun-Gi
- 작성일2023.12.04
- Views1317
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Safely removing nanoplastics from water using 'Prussian blue', a pigment used to dye jeans
- Microplastics can be removed by 99% with flocculants alone, without any additional equipment, by irradiating them with sunlight. Plastic waste breaks down over time into microplastics (<0.1 μm). Microplastics smaller than 20 μm cannot be removed in currently operating water treatment plants and must be agglomerated to a larger size and then removed. Iron (Fe) or aluminum (Al) based flocculants are used for this purpose, but they are not the ultimate solution as they remain in the water and cause severe toxicity to humans, requiring a separate treatment process. Dr. Jae-Woo Choi of the Center for Water Cycle Research at the Korea Institute of Science and Technology (KIST) has developed an eco-friendly metal-organic skeleton-based solid flocculant that can effectively aggregate nanoplastics under visible light irradiation. Prussian blue, a metal-organic frameworks-based substance made by adding iron (III) chloride to a potassium ferrocyanide solution, is the first synthetic pigment used to dye jeans a deep blue color and has recently been used to adsorb cesium, a radioactive element, from Japanese nuclear plant wastewater. While conducting experiments on the removal of radioactive materials from water using Prussian blue, the KIST research team discovered that Prussian blue effectively aggregates microplastics under visible light irradiation. [Figure 1] NANOPLASTIC TREATMENT USING FEHCF NANOBOTS UNDER VISIBLE-LIGHT IRRADIATION The research team developed a material that can effectively remove microplastics by adjusting the crystal structure to maximize the aggregation efficiency of Prussian blue. When the developed material is irradiated with visible light, microplastics with a diameter of about 0.15 μm (150 nm), which are difficult to remove using conventional filtration technology, can be agglomerated to a size about 4,100 times larger, making them easier to remove. In experiments, the researchers found that they were able to remove up to 99% of microplastics from water. The developed material is also capable of flocculating microplastics more than three times its own weight, outperforming the flocculation efficiency of conventional flocculants using iron or aluminum by about 250 times. [Figure 2] Schematics of the preparation of the FeHCH nanobots and process for NP removal The material not only uses Prussian blue, which is harmless to the human body, but is also a solid flocculant, making it easy to recover residues in water. It also uses natural light as an energy source, enabling a low-energy process. "This technology has a high potential for commercialization as a candidate material that can be applied to general rivers, wastewater treatment facilities, and water purification plants," said Dr. Choi of KIST. "The developed material can be utilized not only for nanoplastics in water, but also to clean up radioactive cesium, thus providing safe water." Meanwhile, Dr. Youngkyun Jung, the first author of the paper, said, "The principle of this material can be utilized to remove not only microplastics, but also a variety of contaminants in water systems." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ The research, which was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) through the Material Innovation Leading Project (2020M3H4A3106366) and the KIST Institutional Project (2E32442), was published on October 1 in the international journal Water Research*. Journal : Water Research Title : Visible-light-induced Self-propelled Nanobots Against Nanoplastics Publication Date : 1-October-2023 DOI :https://doi.org/10.1016/j.watres.2023.120543
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- WriterDr. Choi, Jae Woo
- 작성일2023.10.20
- Views2665
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Using AI to develop hydrogen fuel cell catalysts more efficiently and economically
- Development of a new ternary alloy (Cu-Au-Pt) catalyst that is cheaper and more efficient than traditional platinum (Pt) catalysts Proton exchange membrane hydrogen fuel cells (PEMFCs) used in hydrogen vehicles use expensive platinum catalysts to facilitate the oxygen reduction reaction at the anode. There are a vast number of elemental combinations and compositions that need to be explored to develop more efficient and cost-effective catalyst materials than platinum, and researchers are still doing a lot of trial and error in the lab. The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) announced that Dr. Donghun Kim and Dr. Sang Soo Han of the Computational Science Research Center, Dr. Jong Min Kim of the Materials Architecturing Research Center, and Prof. Hyuck Mo Lee of the Department of Materials Science and Engineering at the Korea Advanced Institute of Science and Technology (KAIST, President Kwang Hyung Lee) have presented a new artificial intelligence-based catalyst screening methodology and succeeded in developing a new catalytic material based on a ternary element-based alloy (Cu-Au-Pt) that is cheaper and performs more than twice as well as pure platinum catalysts. [Figure 1] GRAPHICAL ABSTRACT OF MACHINE LEARNING-DRIVEN HYDROGEN FUEL CELL CATALYST DESIGN The team developed Slab Graph Convolutional Neural Network (SGCNN) artificial intelligence model to accurately predict the binding energy of adsorbates on the catalyst surface. This is not the first application of AI to materials discovery. The SGCNN model was developed by evolving the CGCNN model, which is specialized in predicting bulk properties of solid materials, to predict surface properties of catalytic materials. However, there is a big difference between predicting bulk properties and surface properties. When you can quickly and accurately predict the surface properties of a catalyst, you can more efficiently screen for catalysts that meet the triple bottom line of material stability, performance, and cost. In fact, when developing fuel cell anode reaction catalysts using this methodology, we were able to explore the potential of nearly 3,200 ternary candidate materials in just one day, a scale that would have taken years using the density functional theory (DFT) adsorption energy simulation calculations traditionally used to predict catalyst properties. [Figure 2] Machine learning-driven material screening workflow for each anode and cathode of fuel cell The researchers developed a novel ternary (Cu-Au-Pt) alloy catalyst through experimental validation of 10 catalysts with the potential to outperform platinum catalysts out of approximately 3,200 candidate materials. The catalyst uses only 37% of the element platinum compared to pure platinum catalysts, but the kinetic current density is more than twice as high as that of pure platinum catalysts. The catalyst also exhibits excellent durability, with little degradation after 5,000 stability tests. "In the future, we plan to continue to build high-quality adsorption energy data and perform more sophisticated AI modeling, which will further improve the success rate of catalytic material development," said Dr. Kim of KIST. The new methodology has the advantage of being immediately applicable not only to catalysts for hydrogen fuel cells, but also to various catalytic reactions such as water electrolysis-based hydrogen production, which is essential for the realization of the hydrogen economy. The team plans to further reduce the unit cost and improve the performance of the developed catalysts through material and system optimization. ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ The research was supported by the Samsung Future Technology Fostering Project (SRFC-MA1801-03) of Samsung Electronics (CEO Kye-hyun Kyung) and the Materials Research Data Platform Project of the Ministry of Science and ICT (Minister Jong-ho Lee), and was published in the international journal Applied Catalysis B: Environmental. Journal : Applied Catalysis B: Environmental Title : Machine learning filters out efficient electrocatalysts in the massive ternary alloy space for fuel cells Publication Date : 24-July-2023 DOI :https://doi.org/10.1016/j.apcatb.2023.123128
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- WriterDr. Kim, Donghun
- 작성일2023.10.18
- Views1645
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Ushering in the era of light-powered 'multi-level memories'
- KIST Developed technology to store and manipulate electronic states in quantum dots measuring 10 nanometers or less. We live in an era of data deluge. The data centers that are operated to store and process this flood of data use a lot of electricity, which has been called a major contributor to environmental pollution. To overcome this situation, polygonal computing systems with lower power consumption and higher computation speed are being researched, but they are not able to handle the huge demand for data processing because they operate with electrical signals, just like conventional binary computing systems. The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) announced that Dr. Do Kyung Hwang of the Center for Opto-Electronic Materials & Devices and Professor Jong-Soo Lee of the Department of Energy Science & Engineering at Daegu Gyeongbuk Institute of Science and Technology (DGIST, President Young Kuk) has jointly developed a new zero-dimensional and two-dimensional (2D-0D) semiconductor artificial junction material and observed the effect of a next-generation memory powered by light. Transmitting data between the computing and storage parts of a multi-level computer using light rather than electrical signals can dramatically increase processing speed. [Figure 1] 2D-0D HYBRID OPTICAL MEMORY DEVICES The research team has fabricated a new 2D-0D semiconductor artificial junction material by joining quantum dots in a core-shell structure with zinc sulfide (ZnS) on the surface of cadmium selenide (CdSe) and a molybdenum sulfide (MoS2) semiconductor. The new material enables the storage and manipulation of electronic states within quantum dots measuring 10 nm or less. When light is applied to the cadmium selenide core, a certain number of electrons flow out of the molybdenum sulfide semiconductor, trapping holes in the core and making it conductive. The electron state inside cadmium selenide is also quantized. Intermittent light pulses trap electrons in the electron band one after the other, inducing a change in the resistance of the molybdenum sulfide through the field effect, and the resistance changes in a cascading manner depending on the number of light pulses. This process makes it possible to divide and maintain more than 0 and 10 states, unlike conventional memory, which has only 0 and 1 states. The zinc sulfide shell also prevents charge leakage between neighboring quantum dots, allowing each single quantum dot to function as a memory. [Figure 2] Electron micrographs of the 2D-0D hybrid surface implemented in this study (top left), memory characteristics generated by light pulses (top right), and polynomial memory characteristics generated by multiple light pulses (bottom). While quantum dots in conventional 2D-0D semiconductor artificial junction structures simply amplify signals from light sensors, the team's quantum dot structure perfectly mimics the floating gate memory structure, confirming its potential for use as a next-generation optical memory. The researchers verified the effectiveness of the polynomial memory phenomenon with neural network modeling using the CIFAR-10 dataset and achieved a 91% recognition rate. Dr. Hwang of KIST said, "The new multi-level optical memory device will contribute to accelerating the industrialization of next-generation system technologies such as artificial intelligence systems, which have been difficult to commercialize due to technical limitations arising from the miniaturization and integration of existing silicon semiconductor devices." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ This research was supported by the Ministry of Science and ICT (Minister Jong-ho Lee) as a mid-career researcher project and a major project of KIST, and the results were published in the international journal Advanced Materials (IF: 29.4). Journal : Advanced Materials Title : Probing optical multi-level memory effects in single core-shell quantum dots and application through 2D-0D hybrid inverters Publication Date : 19-July-2023 DOI :https://doi.org/10.1002/adma.202303664
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- WriterDr. Hwang, Do Kyung
- 작성일2023.10.17
- Views1327
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A cheaper, safer alternative to lithium-ion batteries: aqueous rechargeable batteries.
- Automatic conversion of hydrogen gas into water makes batteries safer - A breakthrough technology for the commercialization of cheaper, safer aqueous rechargeable batteries This summer, the planet is suffering from unprecedented heat waves and heavy rainfalls. Developing renewable energy and expanding associated infrastructure has become an essential survival strategy to ensure the sustainability of the planet in crisis, but it has obvious limitations due to the volatility of electricity production, which relies on uncertain variables like labile weather conditions. For this reason, the demand for energy storage systems (ESS) that can store and supply electricity as needed is ever-increasing, but lithium-ion batteries (LIBs) currently employed in ESS are not only highly expensive, but also prone to potential fire, so there is an urgent need to develop cheaper and safer alternatives. A research team led by Dr. Oh, Si Hyoung of the Energy Storage Research Center at the Korea Institute of Science and Technology (KIST) has developed a highly safe aqueous rechargeable battery that can offer a timely substitute that meets the cost and safety needs. Despite of lower energy density achievable, aqueous rechargeable batteries have a significant economic advantage as the cost of raw materials is much lower than LIBs. However, inveterate hydrogen gas generated from parasitic water decomposition causes a gradual rise in internal pressure and eventual depletion of the electrolyte, which poses a sizeable threat on the battery safety, making commercialization difficult. [Figure 1] CAUSES OF HYDROGEN GENERATION AND INCESSANT ACCUMULATION WITHIN THE CELL IN THE AQUEOUS RECHARGEABLE BATTERIES Until now, researchers have often tried to evade this issue by installing a surface protection layer that minimizes the contact area between the metal anode and the electrolyte. However, the corrosion of the metal anode and accompanying decomposition of water in the electrolyte is inevitable in most cases, and incessant accumulation of hydrogen gas can cause a potential detonation in long-term operation. [Figure 2] Proposed strategy for securing safety of the aqueous rechargeable batteries via water-regeneration To cope with this critical issue, the research team has developed a composite catalyst consisting of manganese dioxide and palladium, which is capable of automatically converting hydrogen gas generated inside the cell into water, ensuring both the performance and safety of the cell. Manganese dioxide does not react with hydrogen gas under normal circumstances, but when a small amount of palladium is added, hydrogen is readily absorbed by the catalysts, being regenerated into water. In the prototype cell loaded with the newly developed catalysts, the internal pressure of the cell was maintained well below the safety limit, and no electrolyte depletion was observed. [Figure 3] Role of composite catalysts in activating water-regeneration chemical reaction The results of this research effectively solves one of the most concerning safety issues in the aqueous batteries, making a major stride towards commercial application to ESS in the future. Replacing LIBs by cheaper and safer aqueous batteries can even trigger a rapid growth of global market for ESS. "This technology pertains to a customized safety strategy for aqueous rechargeable batteries, based on the built-in active safety mechanism, through which risk factors are automatically controlled." said Dr. Oh, Si Hyoung of KIST. "Moreover, it can be applied to various industrial facilities where hydrogen gas leakage is one of major safety concerns (for instance, hydrogen gas station, nuclear power plant etc) to protect public safety." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ This research was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) through the Nano Future Material Source Technology Development Project and the Mid-Career Researcher Support Project, and the results were published on August 1 in the international journal Energy Storage Materials (IF 20.4). Journal : Energy Storage Materials Title : Highly safe aqueous rechargeable batteries via electrolyte regeneration using Pd-MnO2 catalytic cycle Publication Date : 1-August-2023 DOI :https://doi.org/10.1016/j.ensm.2023.102881
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- WriterDr. Oh, Si Hyoung
- 작성일2023.10.16
- Views1952
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New technology for customized air purification of toxic gases
- KIST's iron oxide-graphene oxide heterostructure improves removal efficiency of harmful volatile organic compounds by up to 15 times Volatile organic compounds (VOCs) in daily products such as paints, adhesives, furniture, cosmetics, and deodorants make our lives easier. However, constant exposure can cause serious health problems such as respiratory illness, headaches, dermatitis, and cancer. Natural ventilation is the most effective way to reduce VOCs in indoor air, but recently, air purifiers have become a common method to maintain indoor air quality due to the frequent extreme outdoor condition (e.g. high concentration of fine dust, heat waves, and extreme cold). Generally, air purifiers remove VOCs by adsorption using activated carbon, which has a non-polar carbon surface and a large specific surface area. This activated carbon can effectively remove non-polar substances such as toluene and benzene, but cannot remove polar substances such as ketones and aldehydes. The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) announced that Dr. Jiwon Lee and Dr. Youngtak Oh from the Center for Sustainable Environment Research have developed a new adsorbent technology that can efficiently adsorb amphiphilic VOCs, which have both hydrophilic and hydrophobic properties and are difficult to remove with existing activated carbon technology. [Figure 1] ADSORPTION MECHANISM AND ADSORPTION PERFORMANCE GRAPH OF IRON OXIDE GRAPHENE ADSORBENT FOR POLAR VOCS The KIST research team synthesized a graphene-iron oxide heterostructure by precisely controlling the surface oxidation of graphite and iron, resulting in a high adsorption capacity for amphiphilic VOCs due to the increase of oxygen functional groups and iron oxide on the surface. This unique adsorbent showed up to 15 times better adsorption efficiency for amphiphilic VOCs than conventional activated carbon adsorbents. They also found that precise oxygen functional groups and iron oxides control of the adsorbent can offer flexible surface optimization freedom for a desirable nature of the pollutant. By testing four different ketones that are difficult to control with activated carbon adsorbents, the researchers found the correlation between the length of carbon chains and the adsorption efficiency; by optimizing the content of oxygen functional groups and iron oxides in the adsorbent, they were able to bring the maximum removal efficiency for the ketones. The researchers also analyzed the sub-nanometer electron transfer phenomenon between the adsorbent and VOC molecules; they found a link between the geometric shape of the pollutant and its adsorption trend for the first time. This is expected to enable the development of customized detection and control technologies for various air pollutants in our environment. "Unlike previous studies that focused on mere improvement of the adsorption performance and regeneration efficiency of adsorbents, we succeeded in developing a breakthrough material that exceeds the limits of existing adsorbents using accessible materials such as graphite and iron, which have high commercialization potential," said Dr. Jiwon Lee. ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ The research, which was conducted as a major project of KIST (Air Environment Research Program) with support from the Ministry of Science and ICT (Minister Jong-ho Lee), was published on October 1 in the Chemical Engineering Journal. Journal : Chemical Engineering Journal Title : Effect of adsorbate geometry and hydrogen bonding on the enhanced adsorption of VOCs by an interfacial Fe3O4?rGO heterostructure Publication Date : 9-August-2023 DOI : https://doi.org/10.1016/j.cej.2023.145346
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- WriterDr. Lee, Jiwon, Dr. Oh, Youngtak
- 작성일2023.10.12
- Views1143
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Make diagnosing serious geriatric diseases as easy as measuring blood sugar
- Developed a new biosensor for measuring glutamine with greater convenience and accuracy than before - Successfully monitored real-time changes in the concentration of glutamine in living cells In 2023, life expectancy in Korea will be 83.6 years, the third highest among OECD countries, and it is steadily increasing every year. As the proportion of the elderly population increases, the social cost of treating various geriatric diseases is also increasing rapidly, and there is a growing interest in early diagnosis of diseases. Among the various diagnostic methods, researchers are actively conducting research on measuring glutamine as an indicator of geriatric diseases by finding that the concentration of glutamine in the cells and blood of patients with serious diseases such as cancer, diabetes, and dementia is significantly changed compared to normal people. Dr. Seo, Moon-Hyeong of the Natural Product Research Center at the Korea Institute of Science and Technology (KIST), together with Dr. Park, Keunwan of the Natural Product Informatics Research Center, have developed a technology that can quickly and accurately measure glutamine concentrations without complicated measurement processes and expensive analytical equipment through the principle of 'ligand-induced protein assembly'. [Figure 1] SCHEMATIC OF Q-SHINE SENSOR DEVELOPMENT BASED ON THE PRINCIPLE OF 'LIGAND-INDUCED PROTEIN ASSEMBLY' THROUGH SPLIT AND STABILIZATION DESIGN OF A GLUTAMINE-BINDING PROTEIN Glutamine is an amino acid in the blood that is used by cells to synthesize proteins or as an energy source, and its rapid fluctuation in certain situations makes it a useful biomarker for the treatment and early diagnosis of disease. For this reason, researchers are actively studying glutamine metabolism in the body to diagnose metabolic and degenerative diseases, including cancer treatment by inhibiting the metabolism of glutamine, which is also a nutrient for cancer cells. Until now, the measurement of glutamine concentration in the body has relied on expensive specialized analytical equipment such as amino acid analyzers, which cannot measure changes in glutamine concentration in living cells in real time. In the case of relatively low-cost research kits, cumbersome pre-treatment processes such as protein removal in biological samples were required, resulting in long measurement times and low accuracy. The team developed a sensor protein for measuring glutamine based on the principle of "ligand-induced protein assembly" that can easily measure the concentration of glutamine in the blood. By separating a glutamine binding protein into two artificial proteins and then binding to the sample, and named it Q-SHINE by combining Q, the symbol for glutamine, and SHINE, which means brightly glowing. Experiments showed that the Q-SHINE sensor was highly selective, not responding to amino acids with similar structure such as glutamic acid and D-glutamine. The lowest concentration of glutamine that can be measured is 1 micromolar (µM, one millionth of a molar), which is 20 times lower than the enzymatic assay most commonly used in research kits. In addition, the sensor protein can be easily produced in E. coli, making it possible for a research kit to analyze glutamine concentrations at the same level as analytical instruments worth hundreds of millions of dollars. [Figure 2] Glutamine concentration measurement results using the Q-SHINE sensor The team also used the Q-SHINE sensor to monitor changes in glutamine concentration in the cytoplasm and mitochondria of living cells in real time. In particular, by verifying the difference in glutamine concentration between cancer cells and normal cells, it is expected to speed up the development of anticancer drugs by inhibiting glutamine metabolism. "The Q-SHINE sensor developed by KIST will enable easy monitoring of glutamine concentration, similar to the self-monitoring of blood glucose by diabetics," said Dr. Seo, Moon-Hyeong. "If used for glutamine metabolism research, it will greatly contribute to early diagnosis and identification of causes of severe geriatric diseases such as cancer, diabetes, and dementia, as well as development of cancer drugs that regulate glutamine metabolism." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ The research, which was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) through the KIST Major Project and the Korea Research Foundation's Excellent New Research Project, was published in the latest issue of the international journal Sensors and Actuators, B: Chemical (IF=8.4, top 0.8% in JCR). Journal : Sensors and Actuators: B. Chemical Title : Q-SHINE: A versatile sensor for glutamine measurement via ligand-induced dimerization Publication Date : 1-September-2023 DOI : https://doi.org/10.1016/j.snb.2023.133951
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- WriterDr. Seo, Moon-Hyeong
- 작성일2023.10.11
- Views856
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A 130g soft robot gripper lifts 100kg?
- Developing a soft robotic gripper that mimics a woven structure - Achieve high performance, cost-effectiveness, and process efficiency in a soft robotic gripper Utilizing soft, flexible materials such as cloth, paper, and silicone, soft robotic grippers is an essential device that acts like a robot's hand to perform functions such as safely grasping and releasing objects. Unlike conventional rigid material grippers, they are more flexible and safe, and are being researched for household robots that handle fragile objects such as eggs, or for logistics robots that need to carry various types of objects. However, its low load capacity makes it difficult to lift heavy objects, and its poor grasping stability makes it easy to lose the object even under mild external impact. [Figure 1] GRIPPER SCHEMATIC WITH WEAVE STRUCTURE Dr. Song, Kahye of the Intelligent Robotics Research Center at the Korea Institute of Science and Technology (KIST), along with Professor Lee, Dae-Young of the Department of Aerospace Engineering at the Korea Advanced Institute of Science and Technology (KAIST), have jointly developed a soft gripper with a woven structure that can grip objects weighing more than 100 kg with 130 grams of material. To increase the loading capacity of the soft robot gripper, the research team applied a new structure inspired by textiles, as opposed to the conventional method of developing new materials or reinforcing the structure. The weaving technique they focused on involves tightly intertwining individual threads to create a strong fabric, which can reliably support heavy objects and has been used for centuries in clothing, bags, and industrial textiles. The team used thin PET plastic The grippers were designed to allow the strips to intertwine and unwind into a woven structure. [Figure 2] Gripper behavior and performance The resulting woven gripper weighs 130 grams and can grip an object weighing 100 kilograms. Conventional grippers of the same weight can lift no more than 20 kilograms at most, and considering that a gripper that can lift the same weight weighs 100 kilograms, the team succeeded in increasing the load capacity relative to its own weight. Also, the soft robot gripper developed by the research team uses plastic, which costs only a few thousand won per unit of material, and can be used as a universal gripper that can grip objects of various shapes and weights, making it highly competitive in price. In addition, since the soft robot gripper can be manufactured by simply fastening a plastic strip, the manufacturing process can be completed in less than 10 minutes, and it is easy to replace and maintain, so the process efficiency is excellent. [Figure 3] Comparison of gripper weight to payload (maximum weight the robot can lift) for the woven gripper, soft gripper, and rigid gripper In addition to PET, which is the main material used by the research team, the gripper can also be made of various materials such as rubber and compounds that possess elasticity, allowing the team to customize and utilize grippers suitable for industrial and logistics sites that require strong gripping performance or various environments that need to withstand extreme conditions. "The woven structure gripper developed by KIST and KAIST has the strengths of a soft robot but can grasp heavy objects at the level of a rigid gripper," said Dr. Song. It can be manufactured in a variety of sizes, from coins to cars, and can grip objects of various shapes and weights, from thin cards to flowers, so it is expected to be used in fields such as industry, logistics, and housework that require soft grippers." ### KIST was established in 1966 as the first government-funded research institute in Korea. KIST now strives to solve national and social challenges and secure growth engines through leading and innovative research. For more information, please visit KIST’s website at https://eng.kist.re.kr/ KAIST is the first and top science and technology university in Korea. KAIST has been the gateway to advanced science and technology, innovation, and entrepreneurship, and our graduates have been key players behind Korea’ innovations. KAIST will continue to pursue advances in science and technology as well as the economic development of Korea and beyond. (https://www.kaist.ac.kr/en) The research was supported by the Ministry of Science and ICT (Minister Lee Jong-ho) through the KIST Major Project and the Korea Research Foundation Basic Research Program, the Overseas Advanced Scientist Invitation Program, and the Basic Research Laboratory Support Program. The results of the study were published on August 2 in the international journal Nature Communications (IF:16.6, top 8.2% in JCR) and were selected as Editors' Highlights, which introduces the best 50 papers in each field. Journal : Nature Communications Title : Grasping through dynamic weaving with entangled closed loops Publication Date : 2-August-2023 DOI : https://doi.org/10.1038/s41467-023-40358-y
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- WriterDr. Song, Kahye
- 작성일2023.10.06
- Views1754