Introduction Research
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Smart labs for bespoke synthesis of nanomaterials are emerging
- Smart labs powered by AI robots are 500x more efficient in material development than simple automation - Expect a new R&D paradigm to address the aging research workforce In the early 20th century, the development of a catalyst for ammonia synthesis by the Haber-Bosch method took more than 10,000 experiments before it was successful. The development of new materials is a time-consuming and costly process from design to commercialization. However, in recent years, researchers have been working to shorten the development period by using artificial intelligence (AI). When combined with robots, it is possible to conduct material development research 24 hours a day, 365 days a year without human intervention. The Korea Institute of Science and Technology (KIST) announced that Dr. Sang Soo, Han and Dr. Donghun, Kim of the Computational Science Research Center and Professor Kwan-Young Lee of the Department of Chemical Engineering and Biotechnology at Korea University (President Kim Dong-won) have developed a bespoke synthesis platform of nanomaterials using AI and robotics, called Smart Lab. The KIST-Korea University joint research team first developed an automated device that synthesizes nanoparticles based on a robotic arm and measures the optical properties of the synthesized nanoparticles. By combining AI technology with this, a smart laboratory for bespoke synthesis of nanomaterials was developed, with which researchers can readily synthesize nanomaterials that meet their requirements just by inputting the desired material properties. The AI technology applied to the Smart Lab platform combines a Bayesian optimization method with the early stopping technology to increase the efficiency for material discovery by more than 500 times compared to simple automated devices. Human experiments are often difficult to obtain reproducible results because the results are very sensitively dependent on the research environment and the proficiency of researchers; however, the developed smart lab has the advantage of producing consistent, high-quality data in large quantities. The researchers also developed an AI technology to ensure the safety of smart labs. Although there is no risk of injury to researchers in unmanned smart labs, it is difficult to prevent safety accidents such as malfunctions due to robot overload. The researchers developed an AI vision technology (DenseSSD) to detect and prevent such safety accidents in advance and installed it in the smart lab. DenseSSD detects various objects in the lab, including research equipment and materials, and notifies users of any abnormalities so that they can take appropriate measures. "The smart lab platform, which enables material development without human intervention, will be a new R&D paradigm that can solve the problem of declining research manpower due to aging," said Dr. Sang Soo, Han of KIST. "In the future, we plan to incorporate interactive language models such as ChatGPT to make it easier for non-experts to use the smart lab," said Dr. Donghun, Kim. The research team plans to expand the Smart Lab platform to various material fields such as catalysts, batteries, and displays. [Figure 1] KIST Computational Science Research Center Smart Lab development staff photo [Figure 2] Conceptualization of a closed-loop experimentation phase with AI robots [Figure 3] Illustration of quantitative efficiency of AI-powered experimental design versus traditional methodologies ### 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 Ministry of Science and ICT (Minister Lee Jong-ho) through the Korea Research Foundation's Nano and Materials Technology Development Project, and the results were published online March 6 and February 22 in the international journals Advanced Functional Materials and npj Computational Materials, respectively.
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- WriterDr. Han Sang Soo
- 작성일2024.05.07
- Views52
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Developing thermal radiation controllable epsilon-near-zero material that can withstand extreme environments
- Unlike conventional refractory conductimaterials, it not oxidizeand maintains performance at temperatures up to 1,000°C in air - Expected to be used in a wide range of extreme environments, including space, aerospace and thermophotovoltaic(TPV) system. Thermal radiation is electromagnetic radiation emitted by all objects with temperature and most representatively, there is the solar radiation spectrum that enters the Earth and causes the greenhouse effect. Controlling and utilizing the thermal radiation energy emitted from solar power, thermal power generation, and residual heat in industrial sites can reduce the cost of electricity production. Therefore, interest in radiation spectrum controlling technology is increasing in areas such as cooling, heat dissipation, and energy production. Until now, radiation spectrum control technology has been mainly used in general environmental conditions, but recently, materials that can withstand extreme environments such as space, aviation and TPV system are needed. Korea Institute of Science and Technology (KIST) announced that a team led by senior researcher Jongbum Kim at the Nanophotonics Research Center has developed a refractory material for controlling thermal radiation spectrum that maintains optical properties even at high temperatures of 1,000°C in air atmosphere and strong ultraviolet illumination. The team fabricated lanthanum-doped barium stannate oxide ("LBSO") as a nanoscale thin film with no lattice strain by pulsed laser deposition. Unlike conventional refractory conducting materials such as tungsten, nickel, and titanium nitride, which are easily oxidized at high temperatures, the LBSO material maintained its performance even when exposed to high temperatures of 1,000°C and intense ultraviolet light of 9 MW/cm2. The researchers then fabricated a thermal emitter based on a multilayer structure with high spectral selectivity in the infrared band using LBSO, and found that the multilayer structure was stable to heat and light as with the single layer thin film, confirming its applicability to TPV power generation technology. The LBSO material allows thermal radiation to be transferred to the PV cell without any additional methods to prevent it from oxidizing in contact with air. "As an alternative to solar and wind renewable energy, whose electricity production varies depending on the weather, eco-friendly thermoelectric power generation technology that uses radiant energy emitted by the Sun and high-temperature environments to generate electricity is gaining attention," said KIST senior researcher Jongbum Kim. "LBSO will contribute to addressing to climate change and the energy crisis by accelerating the commercialization of thermoelectric power generation." The researchers expect that LBSO can be applied not only to thermoelectric power generation technology and recycling of waste heat from industrial equipment, but also to technology for managing heat generated by exposure to and absorption of strong sunlight in extreme environments such as space and aviation, as it is highly resistant to UV exposure. [Fig 1] Schematic diagram of the application of LBSO thermal emitter in TPV energy conversion technology This diagram illustrates the effects of applying LBSO thermal emitter to TPV technology. In the case of a typical blackbody, when it absorbs heat, it emits radiant energy over a very broad wavelength range. However, this results in the emission of radiation energy at wavelengths that cannot be utilized by TPV cells, leading to reduced efficiency. By applying LBSO thermal emitters, it can selectively emit heat in the wavelength range where the TPV cells have the highest efficiency, increasing the overall energy generation efficiency. [Fig 2] Thermal durability of LBSO thin film and LBSO thermal emitter (Above) Changes in the crystal structure and optical properties of LBSO thin films before and after heat exposure. Metal oxides like ITO and AZO, which have similar properties with LBSO, exhibit changes in optical properties such as plasma frequency and damping coefficient when exposed to temperatures below 400 degrees. In contrast, LBSO maintains stable performance even up to 1000 degrees. (Below) Scanning electron microscope image and crystal structure of a multilayer structure including LBSO. The thermal emitter shows minimal changes in its characteristics when exposed to high temperatures and intense ultraviolet laser illumination in the air, as with the single layer. [Fig 3] Surface changes of LBSO thin films before and after heat treatment Surface changes of the thin film at various temperatures and laser intensities during heat exposure. It was observed that fine nanostructures formed on the surface; however, it was experimentally confirmed that these particles did not affect the material's linear optical properties. Semiconductor materials absorb light with higher energy than their bandgap, and exposure to intense ultraviolet light can induce changes in material properties. However, experimental evidence shows that LBSO material remains unchanged in its characteristics even when exposed to intense UV excimer laser, strong enough for the thin film to be etched. ### 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 Jong-ho Lee) through the Information and Communication Technology Development Project and Standard Development Support Project (RS-2023-00223082) and the KIST Future Source Research Project, was published in the international journal Advanced Science (IF: 15.1, JCR(%): 6.2) was published on Nov. 23. Journal : Nature Communications Title : Perovskite Lanthanum-Doped Barium Stannate: A Refractory Near-Zero-Index Material for High-Temperature Energy Harvesting Systems Publication Date : 2023.11.23. DOI : https://doi.org/10.1002/advs.202302410
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- WriterDr. Kim, Jongbum
- 작성일2024.02.06
- Views221
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Development of real-time trace hydrogen gas leakage via a novel terahertz-wave optical platform
- Novel approach for real-time detection of ultra-low levels of hydrogen gas leakageusing palladium materials embedded in Terahertz Metamaterials. - Successfully elucidation of underlying mechanism of metal-light interaction during a genesis of nano-water film Hydrogen gas is the smallest and lightest of all known molecules, and its colorless and odorless nature makes it easy to leak. Also when concentrated above 4% in a confined space, it poses a risk of ignition or explosion. In order for hydrogen to become a major player in the future energy industry, it is essential to ensure the safety issues via ultra-sensitive gas detection technology over the entire gas-dealing processes such as gas production, storage, and transportation. However, conventional gas-leakage sensors using electric signals are prone to yield electrical sparks, which can cause an explosion of leaked hydrogen gas. In addition, the mainstream electrode-based contact sensors affect the effective signal stability depending on the device's contact state showing weak signal fidelity. Thus, it is desirable for achieving stable, non-explosive via non-contact mode detection for removing any possible dangers have been spiring to develop a secure device that does not lead to disaster situations. The Korea Institute of Science and Technology (KIST) announced that a team led by Dr. Minah Seo of the Sensor Systems Research Center & KU-KIST Graduate School and Prof. Yong-Sang Ryu of School of Biomedical Engineering, College of Health Sciences, Korea University, has developed a non-contact terahertz light sensor. This can detect hydrogen gas leaks as small as 0.25% in real-world environments at room temperature and pressure, which is the world-top level of limit-of-detection performance via optical detection methods. Spectroscopy is the non-contact observation method measuring changes in the value of optical constants of an analytic sample. In this method, changes in the reacting substance are observed non-invasively, by measuring variations in the optical properties when the reacting substance encounters hydrogen gas. Terahertz electromagnetic waves have a very wide frequency band, which makes them sensitive to the natural vibrations of gas molecules, and can be utilized in spectroscopy to resolve minute unique information and differences in molecules such as various gases, DNA, and amino acids. However, due to the low probability of interaction with trace amounts of hydrogen gas and the lack of technology to amplify the signal of terahertz waves, it has been difficult to utilize in practice. The research team focused on the property of hydrogen permeating into palladium metal, and devised a research strategy to address this through the interaction of light and matter. The researchers developed a gas-detection sensing platform that can sensitively measure changes in terahertz optical signals caused by trace amounts of gas using metamaterials that have the ability to amplify signals in specific bands of electromagnetic waves. The team first developed a terahertz metamaterial that can amplify signals in the gas-sensitive terahertz band, and then uniformly applied palladium to the metamaterial to create an extremely narrow 14 nm space to maximize the sensitivity of the terahertz signal. The palladium plays bifunctional roles in not only the catalytic reaction of adsorbed hydrogen and oxygen to produce water molecules on the surface, but also in the hydrogen storage. For mimicry of real-world environments (80 % of Nitrogen, 20 % of Oxygen), Hydrogen and oxygen gases were then injected into the developed sensing chamber and exposed to the terahertz sensing platform. The results showed great responsibility with respect to exposed hydrogen gas via significant optical signal variation, and these were scientifically analyzed in a real-time fashion. The usage of ultra-thin palladium together with ultra-sensitive optical band width (the terahertz) provided synergetic performance enabling to detect under 1% of hydrogen gas leakage to the real-time detection level. Not only for the superior detection performance, but also the reusability of the detection platforms was considered during platform designing process. In general, metal hydrides such as palladium are difficult to reuse because they are irreversible, meaning they cannot return to their original state after a phase change, but the KIST-Korea University research team secured the reusability of the sample through special processing technology. They also succeeded in developing a technology to contactlessly track the mechanism of hydrogen desorption at the nanometer scale in real time through optical signals. "Existing light sensors have very limited reliability in normal temperature, pressure, and humidity environments, but this is a promising technology that can detect and screen not only gases but also various biochemical substances in extremely small amounts by dramatically increasing sensitivity," said Dr. Minah Seo, lead author of the study. "It is expected to be used to develop a system that can immediately respond to various harmful factors, gases, and diseases through mobile, on-site, and real-time inspections." "In addition to the terahertz measurement technology, it has opened up the possibility of visually checking various gas adsorption and desorption processes and molecular-level chemical reaction mechanisms occurring on metal surfaces," said Professor Ryu Yong-sang of Korea University, lead author of the study. [Fig 1] Observe the metastructure and optical constants of the palladium-catalyzed reaction as a function of the concentration ratio of hydrogen and oxygen, the thickness of the resulting water layer, and the resulting terahertz signal changes. ### 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 KIST Major Project, the National Research Foundation of Korea (No. 2023R1A2C2003898 , and 2021R1A2C2009236) from the Ministry of Science and ICT (Minister Lee Jong-ho), the KIST Major Project, the KU-KIST School Program of Korea University, and the Korea University Intramural Project, and the results were published online on November 23 in the international journal Advanced Materials (IF 29.4, JCR 2.2%). Journal : Advanced Materials Title : Advancements in intense terahertz field focusing over metallic nanoarchitectures for monitoring hidden interatomic gas-matter interactions Publication Date : 2023.11.23. DOI : https://doi.org/10.1002/adma.202308975
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- WriterDr. Seo, Minah
- 작성일2024.02.06
- Views106
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Hybrid energy harvesters that harness heat and vibration simultaneously
- Developing a hybrid energy harvester that goes beyond simple coupling of thermoelectric and piezoelectric devices to generate higher power - Commercial GPS positioning sensor runs successfully, showing promise for real-world applications Harvesting energy sources such as heat, vibration, light, and electromagnetic waves from everyday environments such as industrial sites and automobiles and converting them into electrical energy is known as energy harvesting. Energy harvesting makes it easier to power today's popular IoT sensors and wireless devices that are located in environments where battery replacement is difficult. Dr. Hyun-Cheol Song and Dr. Sunghoon Hur of Electronic Materials Research Center at the Korea Institute of Science and Technology (KIST) have developed a hybrid energy harvesting system that increases power production by more than 50% by combining thermoelectric and piezoelectric effects. The thermoelectric effect, which converts thermal energy from both ends of the device into electrical energy, has a low energy conversion efficiency, and the piezoelectric effect, which converts mechanical vibration into electrical energy, has a high impedance, so energy cannot be reliably harvested. To overcome the limitations of single-mode energy harvesters, hybrid energy harvesters have been proposed in the past, but they are mainly based on simply combining the energy generated by each mechanism. In response, the KIST research team developed a thermoelectric-piezoelectric hybrid energy harvester that complements the shortcomings of thermoelectric and piezoelectric devices to create a synergistic effect in environments with heat sources and vibrations. First, instead of a heat sink, which is a static shape with a large cross-sectional area that is bulky and in contact with air, a cantilever was fabricated to improve the heat dissipation effect in a vibration environment, resulting in a thermoelectric device output that was improved by more than 25%. The researchers also proposed a hybrid energy harvesting structure in which a polymer-type piezoelectric device (MFC) was attached to the cantilever to generate additional power by generating tensile and compressive deformation of the piezoelectric device as the cantilever shakes. The research team successfully applied this hybrid energy harvester to stably drive a commercial IoT sensor (GPS positioning sensor, 3 V, 20 mW), demonstrating the potential for future IoT sensors to run continuously without battery power supply. "This study confirms that the hybrid energy harvesting system can be reliably applied to our real life," said Dr. Sunghoon Hur of KIST, who led the research. "We have confirmed its effectiveness in places where heat and vibration exist together, such as automobile engines, and are currently planning to build a system that can be applied to factory facilities or construction machinery engines that are difficult to supply power and diagnose their condition wirelessly." [Fig 1] Thermoelectric-voltaic hybrid harvester utilizing a cantilevered dynamic heat sink developed by KIST researchers [Fig 2] Graph showing the characteristics of a thermoelectric-voltaic hybrid harvester utilizing a cantilevered dynamic heat sink. [Fig 3] Illustration and graph showing that the output of a thermoelectric-piezoelectric hybrid harvester can be used to reduce IoT sensor drive time, increasing hybrid power due to the synergy of the thermoelectric-piezoelectric mechanism. ### 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 Ministry of Science and ICT (Minister Jong-ho Lee) as Institutional Program of KIST and was published in the latest issue of Energy Conversion and Management (IF: 10.4, top 1.8% in JCR), an international journal in the energy field. Journal : Energy Conversion and Management Title : A synergetic effect of piezoelectric energy harvester to enhance thermoelectric Power: An effective hybrid energy harvesting method Publication Date : 2023.10.30. DOI : https://doi.org/10.1016/j.enconman.2023.117774
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- WriterDr. Hur, Sunghoon
- 작성일2024.02.05
- Views93
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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
- Views590
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Simultaneous electricity generation and filteration of wastewater
- A novel membrane using a combination of a water filteration membrane and conductive polymer - Water quality improvement and continuous electricity generation using a simple operation method The purification of various water resources, such as rain, seawater, groundwater, river water, sewage, and wastewater, into potable or usable water is a high-energy process. So, what if electricity could be generated during the water purification process? In the spotlight, a domestic research team has developed a multifunctional membrane that can simultaneously generate electricity while purifying wastewater into drinking water. The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) has announced that Dr. Ji-Soo Jang's team from the Electronic Materials Research Center and Prof. Tae-Gwang Yoon's team from the Department of Materials Science and Engineering, Myongji University (President Byeong-Jin Yoo) have jointly developed an advanced membrane that can simultaneously provide drinking water and generate continuous electricity from various water resources, such as sewage/wastewater, seawater, and groundwater. The developed "sandwich-like" membrane is composed of a porous membrane that filters water at the bottom and a conductive polymer that generates electricity at the top. The membrane is designed to purify wastewater by controlling the direction of the water flow. Water flowing perpendicularly to the membrane generates direct current by the movement of ions along the horizontal direction. The membrane can reject more than 95% of the contaminants of sizes less than 10 nm (one hundred-millionth of a meter). Hence, microplastics and heavy metal particles in wastewater can be removed, and continuous electricity can be generated for more than 3 h with only 10 µl (microliter) of water. Since the membrane can be manufactured using a simple printing process without size restrictions, it has a high potential to be commercialized due to low manufacturing costs and processing time. The research team is currently conducting follow-up research to generate electricity while improving the water quality of wastewater to the level of drinking water by developing the membrane for an actual factory. Dr. Ji-Soo Jang from KIST expressed his opinion on the research saying that, "As a novel technology that can solve water shortage problem and produce ecofriendly energy simultaneously, it also has great potential applications in the water quality management system and emergency power system." This research was conducted as a major project of KIST with the support of the Ministry of Science and ICT (Minister Jong-Ho Lee). These research findings were published in the latest issue of 'Advanced Materials', an international journal of materials (IF: 32.086, top 2.17% in the JCR field), and were selected to be on the front cover of the issue. Journal: Advanced Materials Title: Bidirectional water-stream behavior on multifunctional membrane for simultaneous energy generation and water purification Publication Date: 9-Dec-2022 DOI: https://doi.org/10.1002/adma.202209076 Electricity generation and water purification membrane developed by the KIST-Myongji University joint research team Schematic illustration for the operation of the electricity generation and water purification membrane developed by KIST-Myongji University joint research team
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- WriterDr. Jang, Ji-Soo
- 작성일2023.02.23
- Views3945
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Development of a Self-resonant Smart Energy Harvester
- Compact 'Energy Harvesting' technology equipped with an autonomous resonance-tuning mechanism - Realization of stable power supply for small electronic devices (IOT sensors) through demonstration The Internet of Things (IoT) requires the installation free of time and space, therefore, needs independent power sources that are not restricted by batteries or power lines. Energy harvesting technology harvests wasted energy such as vibration, heat, light, and electromagnetic waves from everyday settings, such as automobiles, buildings, and home appliances, and converts it into electrical energy. Energy harvesters can generate sufficient electricity to run small electronic devices by harvesting ambient energy sources without an external power supply. The Korea Institute of Science and Technology (KIST, President Seok Jin Yoon) announced that Dr. Hyun-Cheol Song's research team at the Electronic Materials Research Center developed an autonomous resonance tuning (ART) piezoelectric energy harvester that autonomously adjusts its resonance according to the surrounding environment. The developed energy harvester can tune its own resonance over a broad bandwidth of more than 30 Hz, and convert the absorbed vibration energy into electrical energy. The energy harvesting process that converts vibration into electrical energy inevitably causes a mechanical energy loss, which leads to low energy conversion efficiency. This problem can be solved by using the resonance phenomenon in which the vibration amplifies when the natural frequency of an object and the frequency of the vibration match. However, while the natural frequency of the energy harvester is fixed, the various vibrations we experience in our everyday settings have different ranges of frequency. For this reason, the natural frequency of the harvester must be adjusted to the usage environment every time in order to induce resonance, making it difficult to put into practical use. Accordingly, the KIST research team developed a specially designed energy harvester that can tune itself to the surrounding frequency without a separate electrical device. When the energy harvester senses the vibration of the surroundings, an adaptive clamping system (tuning system) attached to the harvester modulates its frequency to the same frequency as the external vibration, thus enabling resonance. As a result, it was possible to quickly achieve resonant frequency tuning within 2 seconds, continuously generating electricity in a broad bandwidth of more than 30Hz. For the real-world validation of the ART function, this energy harvester equipped with a tuning system was mounted on a driving vehicle. Unlike piezoelectric energy harvesters that have been introduced in preceding studies, it successfully drove a wireless positioning device without a battery in an environment where the vibration frequency continuously changed. Dr. Song (KIST), who led this study, said, "This result suggests that energy harvesters using vibrations can be applied to our real life soon. It is expected to be applicable as an independent power source for wireless sensors, including the IOT, in the future." This research was carried out as a KIST major project supported by the Ministry of Science and ICT (Minister Jong-ho Lee), and as an energy technology development project of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) supported by the Ministry of Trade, Industry and Energy (Minister Chang-yang Lee). The results of this study were published as a front cover in the issue of Advanced Science, an international journal in the energy field. Journal: Advanced Science Title: Autonomous Resonance-Tuning Mechanism for Environmental Adaptive Energy Harvesting Publication Date: 28-Nov-2022 DOI: https://doi.org/10.1002/advs.202205179 Schematics for energy harvester structure and adaptive clamping system (above) Graphs showing the characteristics of an ART energy harvester Diagrams showing the potential for practical use of an ART energy harvester that successfully drives a positioning device by utilizing the vibration energy of an automobile engine.
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- WriterDr. Song, Hyun-Cheol
- 작성일2023.02.20
- Views453
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New coating technology that removes toxic agents from chemical weapons developed for practical application against chemi
- A detoxification coating achieved on various materials by complexation of a detoxification catalyst through functional polymer design - Expected to contribute to next-generation protective suits and equipment, as well as to detoxification treatment of chemical leakage Highly toxic organic compounds are colorless, odorless, and can be used to perpetrate massacres in very small amounts; thus, their use is prohibited by the Chemical Weapons Convention worldwide. Nevertheless, there have been reports of chemical weapon use recently, and therefore, there is an emerging need to develop protective materials against such threats. Currently, activated charcoals are used in protective suits and gas masks to remove toxic chemicals by absorption, but they have their own problems, such as secondary contamination; thus, the development of detoxification catalysts that can fundamentally remove toxicity is required. The Korea Institute of Science and Technology (KIST, President Yoon Seokjin) announced that the research team led by Dr. Baek Kyung Youl, a senior researcher at the Materials Architecturing Research Center, succeeded in developing a detoxification composite that can be easily processed into a coating material, continuing on their success in developing a nano-based detoxification catalyst in 2019. The previously developed metal-organic framework (MOF) detoxification catalyst had high performance, but was in the form of particles that break like sand; thus, it had not been put into practical use in coating military uniforms and equipment. To overcome this problem, Baek’s research team designed a functional polymer and mixed it with a detoxification catalyst to develop a detoxification technology that can be processed into films and fibers while maintaining its properties. The research team developed a new functional polymeric support that improves processability while maintaining the high reactivity of the previously developed nanometer-level zirconium (Zr)-based detoxification catalyst, and used it to make a mixed compound that can be used as a detoxification catalyst. It was confirmed to be practically applicable in a detoxification performance test using an actual chemical weapon, the nerve agent soman (GD), on military uniforms and equipment coated with the compound. Dr. Baek of KIST said, “What is different about this compound is that it can remove the toxicity of chemical weapons easily and coat large areas quickly using a simple spray process rather than the conventional electrospinning method”, and that “It is expected that the spray coating can be applied to military uniforms and equipment to prevent contamination and be used to remove toxic agents from equipment, protecting the lives of soldiers and civilians from highly toxic chemical agents.” This study was conducted with the support of the K-DARPA project of KIST and in cooperation with KIST’s Department of National Security, Disaster and Safety Technology. The results of the study have been published online in the latest issue of ACS Applied Materials & Interfaces (IF: 10.383, JCR Top 14.05%). [Fig. 1] Schematic diagram of the strategy for the development of coating materials using the functional polymeric support and nano-detoxification catalyst and the decomposition of chemical agents [Fig. 2] Detoxification catalyst powder developed by KIST researchers (left) and a glass substrate coated with the detoxification catalyst (right)
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- WriterDr. Baek, Kyung Youl
- 작성일2022.11.11
- Views500
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Development of New Technology for Wastewater Treatment for Semiconductor Production
- Photocatalysis-based Prompt and Complete Removal of Trace Amount of Alcohol in Water Alcohols are used to remove impurities on the surface of semiconductors or electronics during the manufacturing process, and wastewater containing alcohols is treated using reverse osmosis, ozone, and biological decomposition. Although such methods can lower the alcohol concentration in wastewater, they are ineffective at completely decomposing alcohols in wastewater with a low alcohol concentration. This is because alcohol is miscible in water, making it impossible to completely separate from alcohol using physical methods, while chemical or biological treatments are highly inefficient. For this reason, wastewater with a low alcohol concentration is primarily treated by diluting it with a large amount of clean water before its discharge. The Korea Institute of Science and Technology (KIST, President Seok-Jin Yoon) has announced that a research team led by Dr. Sang Hoon Kim and Dr. Gun-hee Moon of Extreme Materials Research Center developed a photocatalyst that can completely decompose a trace amount of alcohol in water within a short duration by adding a very trace amount of copper to iron oxide, which is used as a catalyst during the advanced oxidation process. The research team employed Fenton oxidation that uses oxidizing agents and catalysts during the advanced oxidation process for water treatment. Usually alcohols were used as reagents to verify radical production during Fenton oxidation in other advanced oxidation process (AOP) studies, they were the target for removal from semiconductor wastewater in this research. This water treatment technology is expected to dramatically reduce the cost and water resources invested into the treatment of semiconductor wastewater. In the past, clean water with a volume 10 times higher than that of the wastewater under treatment was required for dilution of the wastewater in order to reduce the alcohol concentration of 10 ppm in the wastewater to less than 1 ppm. If the photocatalyst developed by the KIST is used for water treatment, water resources can be saved. The research team applied the photocatalyst to wastewater from a semiconductor factory to prove that alcohol decomposition levels similar to those observed in the laboratory could be achieved in industrial practice. “As large-scale semiconductor production lines are established, we expect that there will be a rapid increase in the demand for the treatment of semiconductor wastewater,” said Dr. Kim. “The results of our research will provide a solution to effectively treat semiconductor wastewater using less resources and at a lower cost,” he added. Image [Figure 1] Mechanism of Isopropyl alcohol (IPA) decomposition during photo-Fenton oxidation using the developed catalyst
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- WriterDr. Kim, Sang Hoon
- 작성일2022.10.20
- Views688
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Enabling Safe Hydrogen Storage Systems For developing novel materials for hydrogen energy storage
Hydrogen is considered a future clean energy source, and thus, building infrastructure and developing core technologies for hydrogen production, storage, transportation, and utilization has attracted significant attention. Among the various hydrogen storage methods, metal hydride-based hydrogen storage systems are considered the safest method to store hydrogen. The Korea Institute of Science and Technology (KIST, President Seokjin Yoon), headed by Dr. Dong Won Chun and Dr. Jin-Yoo Suh, the research teams of the Energy Materials Research Center, and Prof. Kyu Hyoung Lee from the Yonsei University (President Seoung-Hwan Suh), along with their research team, succeeded in the real-time monitoring of the dehydrogenation of metal hydride composites made of Mg and Fe with high nanometer-scale resolution. The joint research team observed the transition of hydrogen atoms from their initial state inside a metal hydride solid to the gaseous state as they move from the outside and calculated the amount of hydrogen that remains inside the metal hydride after the dehydrogenation process. Meanwhile, physical properties of metal hydride were investigated by observing nano-sized samples through an electron microscope; therefore, the reliability of results is questionable. However, the researchers verified that the same phenomenon is reproduced in an experiment when the nano-sized sample (100 nm) is compared with bulk-sized metal hydrate samples (several mm) produced for commercialization. By minimizing sample damage caused by the electron beam, it is possible to observe the movement of hydrogen within the metal, bringing a new phase in the development of hydrogen storage. Dr. Chun said "Hydrogen, with atomic number 1, has one electron and one proton, so it is difficult to observe its movement at the current level of technology, which analyzes the signal of electrons or protons. The research team has introduced a new methodology to observe hydrogen movement within solids. We will apply this technology to the new national challenge of developing solid hydrogen storage systems to build a safe hydrogen storage infrastructure. The final goal is to make hydrogen energy widely available in our daily lives." The research was supported by the Ministry of Science and ICT (Minister Jong-Ho Lee) and was carried out as a major KIST project and as a mid-career researcher project by the National Research Foundation of Korea. The results were published in the latest issue of “Advanced Functional Materials”, a specialized journal on materials and energy. Figure 1. Real-time analysis of hydrogen atom movement and metal hydride dehydrogenation process. Figure 2. Quantification results of hydrogen mobility through observation of hydrogen inside metal hydride. Journal : Advanced Functional Materials Title : Real-Time Monitoring of the Dehydrogenation Behavior of a Mg2FeH6-MgH2 Composite by In Situ Transmission Electron Microscopy 2022.07.19. DOI: https://doi.org/10.1002/adfm.202204147
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- WriterDr. Chun, Dong Won & Dr. Jin-Yoo Suh
- 작성일2022.10.14
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