Photon qubits challenge AI, enabling more accurate quantum computing without error-correction techniques - Implementing molecular structure-level quantum simulations using a single photon qudit - performing more accurate quantum chemistry calculations with fewer resources than conventional overseas studies The just-announced Nobel Prize in Chemistry was awarded to University of Washington Professor David Baker, Google DeepMind CEO Hershavis, and Principal Investigator John Jumper for their work using AI to predict the structure of proteins, enabling the discovery of new drugs and new materials. In an era where AI and data are driving the scientific revolution, quantum computing technology is emerging as another game-changer in the development of new drugs and new materials. Dr. Hyang-Tag Lim's research team at the Center for Quantum Technology at the Korea Institute of Science and Technology (KIST) has implemented a quantum computing algorithm that can estimate interatomic bond distances and ground state energies with chemical accuracy using fewer resources than conventional methods, and has succeeded in performing accurate calculations without the need for additional quantum error mitigation techniques. Quantum computers have the disadvantage of rapidly increasing errors as the computational space grows at the current level. To overcome this, the Variational Quantum Eigensolver (VQE) method, which combines the advantages of classical and quantum computers, has emerged. VQE is a hybrid algorithm designed to use a Quantum Processing Unit (QPU) and a Classical Processing Unit (CPU) together to perform faster computations. Global research teams, including IBM and Google, are investigating it in a variety of quantum systems, including superconducting and trapped-ion system. However, qubit-based VQE is currently only implemented up to 2 qubits in photonic systems and 12 qubits in superconducting systems, and is challenged by error issues that make it difficult to scale when more qubits and complex computations are required. Instead of qubits, the team utilized a higher-dimensional form of quantum information called a qudit. A qudit is a quantum unit that can have multiple states, including 0, 1, and 2, in addition to the 0 and 1 that a traditional qubit can represent, which is advantageous for complex quantum computations. In this study, a qudit was implemented by the orbital angular momentum state of a single-photon, and dimensional expansion was possible by adjusting the phase of a photon through holographic images. This allowed for high-dimensional calculations without complex quantum gates, reducing errors. The team used the method to perform quantum chemistry calculations with VQE to estimate the bond length between hydrogen molecules in four dimensions and lithium hydride (LiH) molecules in 16 dimensions, the first time 16-dimensional calculations have been realized in photonic systems. While conventional VQEs from IBM, Google, and others are required error mitigation techniques for chemical accuracy, the KIST team's VQE achieved chemical accuracy without any error mitigation techniques. This demonstrates how high accuracy can be achieved with fewer resources, showing the potential for widespread application in industries where molecular properties are important. It is also expected to be useful in solving complex problems such as climate modeling. "By securing qudit-based quantum computing technology that can achieve chemical accuracy with fewer resources, we expect it to be used in various practical fields, such as developing new drugs and improving battery performance," said Dr. Hyang-Tag Lim of KIST. ### 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 Yoo Sang-im) through the KIST Institutional Program and the Korea Research Foundation Quantum Computing Technology Development Project (2022M3E4A1043330). The research was published in the international journal Science Advances (IF: 11.7 JCR field top 7.8%). [Figure 1] [Figure 2]

Cracking the Code of Performance Degradation in Solid Oxide Cells at the Atomic Level - Unveiled the initial degradation mechanism at the nanoscale for the first time using advanced transmission electron microscopy (TEM). - Presented new indicators for the development of solid oxide electrolysis materials operated stably at high temperatures (>600°C). Dr. Hye Jung Chang and Dr. Kyung Joong Yoon (Director) of the Hydrogen Energy Materials Research Center at the Korea Institute of Science and Technology (KIST, President Sangrok Oh) have announced that they have elucidated the mechanism of the initial degradation phenomenon that triggers the performance drop of high-temperature solid oxide electrolysis cell systems, using advanced transmission electron microscopy. Unlike previous studies, which analyzed the final stages of degradation at the micrometer scale (1 µm, one-millionth of a meter), this study successfully verified the initial changes in electrolysis cell materials at the nanometer scale (1 nm, one-billionth of a meter). The research team identified the degradation mechanism occurring between the air electrode and electrolyte of the electrolysis cell through TEM diffraction analysis and theoretical calculations. The observations revealed that oxygen ions accumulated at the interface of the electrolyte, known as Yttria Stabilized Zirconia (YSZ), during the oxygen injection process that that drives the electrolysis reaction. Consequently, the atomic structure of the interfacial YSZ is compressed, leading to the formation of nanoscale defects and, eventually, cracks between the air electrode and the electrolyte, which in turn caused the deterioration of the cell's performance. Furthermore, by visually verifying the stress and defects formed at the interface, the team succeeded in elucidating the correlation between ions, atoms, nanoscale defects, pores, and cracks occurring in the early stages of degradation. This research achievement marks the first study to elucidate the degradation mechanism at the nanoscale, providing guidelines to address the performance decline of high-temperature electrolysis cells during long-term operation. Specifically, it could enable the development of materials that can operate stably above 600°C for extended periods, significantly enhancing the durability of commercial electrolysis cells. The nanoscale analytical technology using advanced TEM in this study can be applied to solve degradation issues in various energy devices. The research team plans to accelerate the commercialization of high-temperature electrolysis cells by collaborating with manufacturers to establish automated production processes for mass production. Additionally, they are conducting research to develop new materials that can suppress the accumulation of oxygen ions in specific areas of the electrolysis cell, aiming to increase production efficiency and reduce production costs, ultimately lowering the cost of clean hydrogen production. Dr. Chang from KIST stated, "Using advanced transmission electron microscopy, we were able to identify the causes of previously unknown degradation phenomena at the early stages. Based on this, we aim to present strategies to improve the durability and production efficiency of high-temperature electrolysis cells, contributing to the economic viability of clean hydrogen production." ### 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 Sang Im Yoo) through KIST's major project and the Ministry of Trade, Industry, and Energy (MOTIE) of Korea (Minister Deokgeun Ahn) (P0022331) supervised by the Korea Institute for Advancement of Technology (KIAT), along with National Research Council of Science and Technology (CAP22072-000), The findings have been published in the latest issue of the international journal Energy & Environmental Science (IF 32.4, JCR field 0.9%). [Figure 1] Analysis of Solid Oxide Interfaces Using Advanced Transmission Electron Microscopy (Selected as Back Cover Image for the EES Journal) [Figure 2] Identifying the Cause of Electrode Interface Delamination: Oxygen Ion Accumulation Leads to Changes in Atomic Structure and Formation of Nano Defects [Figure 3] Visualization of Nanoscale Interfacial Stress Identified Through TEM Diffraction Analysis and Density Functional Theory

Breakthrough Idea for CCU Technology Commercialization from 'Carbon Cycle of the Earth' - New silver-silica composite catalyst developed based on the idea of carbonate-silicate geochemical cycling - Controlled local pH and prevention of CO₂ transport degradation through a ‘silica-hydroxide’ cycle The research team led by Dr. Hyung-Suk Oh and Dr. Woong Hee Lee at the Clean Energy Research Center at Korea Institute of Science and Technology (KIST, President Sang-Rok Oh) has developed a silver-silica composite catalyst capable of reversible local pH control through a silica-hydroxide cycle, inspired by Earth’s natural cycles. This research draws inspiration from the carbonate-silicate cycle, known as the Earth’s inorganic carbon cycle, where carbon dioxide (CO₂) maintains balance. CO₂ is removed from the atmosphere as it is stored in weathered minerals, then released back into the atmosphere through volcanic activity. During the weathering of silicate rocks, dissolved silica (SiO₂) is produced, leading to carbonate rock formation, which eventually recycles back into silicate rock through volcanic activity, impacting Earth’s temperature regulation. The key substance in this cycle, silica, was applied to electrochemical CO₂ conversion reactions. Among the catalysts used in CCU technology, silver catalysts are highly effective at converting CO₂ into carbon monoxide (CO), a valuable raw material for petrochemical products. However, silver catalysts are not yet commercially viable, as they exhibit issues at high current densities, such as agglomeration or clumping of particles on the catalyst surface, which rapidly reduces selectivity for CO. To maintain the performance of the silver catalyst, the research team developed a silver-silica composite catalyst. During reactions, hydroxide ions (OH⁻) generated interact with silica, dissolving into a silicate form and precipitating back under neutral conditions, thereby controlling the pH. This approach addresses performance degradation issues at higher current densities without altering the catalyst's physical structure, relying solely on a chemical approach. The newly developed silver-silica composite catalyst showed near 100% selectivity even at a higher current density of 1 A cm⁻², compared to commercial silver catalysts that drop to about 60% selectivity at 800 mA cm⁻². Additionally, the catalyst boosted CO₂ conversion to CO by around 47%, achieving high efficiency even at elevated current densities. This silver-silica composite catalyst successfully enhances CO₂ reduction performance and durability at high current densities, significantly advancing the commercial potential of CCU technology for electrochemical CO₂ conversion. Its high CO selectivity and durability due to reversible cycling enable sustained performance over extended periods, improving productivity and economic feasibility. Moving forward, the team plans to optimize production processes for high-efficiency catalysts and conduct long-term durability testing for potential application in industrial facilities, such as power plants and petrochemical factories. Dr. Oh from KIST stated, “The research provides a significant direction in enhancing catalyst reversibility and environmental control strategies for electrochemical systems. It is expected to contribute to the future demonstration and commercialization of electrochemical 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/ This research was supported by the Ministry of Science and ICT (Minister Sang Im Yoo) through KIST's major project and the Carbon to X project (2020M3H7A1098229), and the Creative Convergence Research Project (CAP21011-100). The findings have been published as a front cover in the international journal ‘Energy & Environmental Science’ (IF 32.4, JCR Top 0.3%). [Figure 1] Diagram Representing Alkaline Issues in a Zero-Gap CO₂ Electrolysis Device [Figure 2] Diagram of the Silica-Hydroxide Cycle Occurring During the Electrochemical CO₂ Reduction Reaction Using a Silver-Silica Reduction Electrode [Figure 3] Front cover image

High-Performance Inkjet Print Head Enhances Bioprinting Productivity - Implementation of high-efficiency, low-heat bioprinting technology using piezoelectric thin film - Expected to expand applications in the organoid field, which was previously challenging due to thermal stability issues Bioprinting is a technology used to create three-dimensional structures, such as human tissues or organs, using bio-inks made of cells and hydrogels. However, conventional inkjet technology has difficulty dispensing bio-inks that are sensitive to temperature due to the heat generated during operation. Furthermore, conventional 3D bioprinting mainly utilizes simple syringe-type printing devices with a single needle, making it time-consuming to produce artificial organs like the brain, lungs, and heart. The Bionics Research Center team, led by Dr. Byung Chul Lee at the Korea Institute of Science and Technology (KIST, President Sang-Rok Oh), in collaboration with Dr. Seung-Hyup Baek’s team at the Electronic Materials Research Center and Professor Tae-Keun Kim’s team at Korea University (President Dong-Won Kim), has developed a bio-ink inkjet print head using the piezoelectric material PMN-PZT. This new print head is thinner but performs better than conventional designs. When applied, it enables the simultaneous dispensing of bio-ink at high resolution in multiple positions, significantly improving bioprinting productivity. The research team developed a multi-nozzle inkjet print head using high-performance PMN-PZT thin films. This technology allows individual control of 16 ink ejection units arranged at 300 μm intervals, resulting in 16 times higher driving efficiency compared to than conventional methods. This enhancement boosts productivity and stability in bioprinting, reducing the production time for artificial organs. In experiments, the team successfully printed hydrogels, a type of bio-ink, at a diameter of 32μm—half the size of conventional methods. The print speed achieved was 1.2 m/s, approximately 60 times faster than traditional methods. Additionally, the heat generation was reduced by 73.4%, keeping the temperature increase below 3.2 degrees Celsius during printing, ensuring a stable output environment. This allows for precise dispensing of high-viscosity materials and minimizes the deformation of temperature-sensitive bio-inks. The PMN-PZT-based print head developed in this research can be utilized in organoid fields such as artificial organ transplants and drug toxicity evaluations, where thermal stability has been challenging. Furthermore, the operating temperature remains below 30 degrees Celsius, preventing the deformation of temperature-sensitive electronic materials and providing a stable printing environment. Therefore, it has the potential for broad application in various industries, including electronic components beyond the medical field. Dr. Lee stated, “The new print head using PMN-PZT thin film material has enhanced the potential for high-resolution 3D organoid model production,” adding, “We plan to commercialize a 3D bioprinter capable of creating organs applicable for transplantation and toxicity evaluation by experimenting with various bio-inks such as gelatin.” ### 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 Sang Im Yoo) through KIST's Major Projects and the National Core Materials Research Project (NRF-2020M3D1A2101933) funded by the Ministry of Science and ICT (Minister Sang-Im Yoo). The research findings were published in the international journal Sensors and Actuators B: Chemical (IF 8.0, JCR field 0.7%). [Figure 1] Schematic of a high-performance piezoelectric material-based print head for bioprinting applications [Figure 2] Experiment results of heat generation based on the driving signal of the inkjet print head [Figure 3] Results of hydrogel printing using the developed print head

New Breakthrough in Quantum Computing Development, Hybrid Quantum Error Correction Technology - Hybrid quantum error correction technology opens new directions for quantum computer development - KIST, University of Chicago, and Seoul National University researchers develop leading core technology through international research cooperation A major challenge in realizing quantum computers is the development of 'quantum error correction' technology. This technology offers a solution for addressing errors that occur in the qubit, the basic unit of quantum computation, and prevents them from being amplified during the computation. Without quantum error correction, it would be impossible for quantum computers to outperform classical counterparts, and thus efforts to advance this technology are ongoing worldwide. Dr. Seung-Woo Lee's research team at the Korea Institute of Science and Technology (KIST)'s Quantum Technology Research Centre has developed the world's first hybrid quantum error correction technique for discrete variables (DV) and continuous variables (CV), and designed a fault-tolerant quantum computing architecture based on hybrid technique. Qubits implementing quantum error correction are called logical qubits, and they can be realized in two different ways: Discrete Variable (DV) and Continuous Variable (CV). Companies such as IBM, Google, Quera, and PsiQuantum are developing quantum computers using the DV method, while Amazon (AWS), Xanadu, and others are adopting the CV method. Each of these two approaches has advantages and disadvantages regarding manipulation difficulty and resource efficiency. KIST researchers have proposed a method to integrate the error correction of DV and CV qubits, which were previously developed separately. They developed a fault-tolerant architecture based on the hybrid technology and demonstrated through numerical simulations that it combines the advantages of both methods, enabling more efficient and effective quantum computation and error correction. In particular, in optical quantum computing, the hybrid approach can achieve the photon loss threshold up to four times higher than existing techniques and can improve the resource efficiency by more than 13 times while maintaining the same level of logic error rate. 'The hybrid quantum error correction technology developed in this study can be combined not only with optical systems but also with superconductors and ion trap systems,' said Dr Jaehak Lee of KIST. 'This research provides a new direction for the development of quantum computing,' said Dr Seung-Woo Lee of KIST, who led the research. 'Hybrid technologies that integrate the advantages of different platforms are expected to play a crucial role in developing and commercializing large-scale quantum computers.‘ KIST signed a memorandum of understanding (MOU) with the University of Chicago in March last year to collaborate on quantum technology research, involving both institutions and Seoul National University. The researchers announced this important achievement in just over a year through international research collaboration, showing the potential to develop core technologies that will lead the world in the highly competitive field of quantum computing. KIST is hosting an international collaborative research centre for the development of core technologies for quantum error correction, with partner institutions including the University of Chicago, Seoul National University, and Canadian quantum computing company Xanadu. ### 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 Sang-Im Yoo) under the KIST Major Project and Quantum Technology Cooperation Project (2022M3K4A1094774). The research results were published on 2 August in the international journal PRX Quantum (IF: 9.2 JCR, top 1.9%). [Figure 1] [Figure 2]

- KIST develops neutron shielding fiber against space radiation - Utilizing BNNTs (boron nitride nanotubes), expected to be applied as a key material for aviation, space, and defense With the success of the Nuri launch last year and the recent launch of the newly established Korea Aerospace Administration, interest in space has increased, and both the public and private sectors are actively investing in space-related industries such as space travel. However, exposure to cosmic radiation is unavoidable when traveling to space. A research team led by Dr. Dae-Yoon Kim from the Center for Functional Composite Materials at the Korea Institute of Science and Technology (KIST) has developed a new composite fiber that can effectively block neutrons in space radiation. Neutrons in space radiation negatively affect life activities and cause electronic devices to malfunction, posing a major threat to long-term space missions. By controlling the interaction between one-dimensional nanomaterials, boron nitride nanotubes (BNNTs), and aramid polymers, the team developed a technique to perfectly blend the two difficult-to-mix materials. Based on this stabilized mixed solution, they produced lightweight, flexible, continuous fibers that do not burn at temperatures up to 500 °C. BNNTs have a similar structure to carbon nanotubes (CNTs), but because they contain a large number of boron in the lattice structure, their neutron absorption capacity is about 200,000 times higher than that of CNTs. Therefore, if the developed BNNT composite fibers are made into fabrics of the desired shape and size, they can be applied as a good material that can effectively block radiation neutron transmission. This means that BNNT composite fibers can be applied to the clothing we wear every day, effectively protecting flight crews, healthcare workers, power plant workers, and others who may be easily exposed to radiation. In addition, the ceramic nature of BNNTs makes them highly heat-resistant, so they can be used in extreme environments. Therefore, it can be used not only for space applications but also for defense and firefighting. "By applying the functional textiles we have developed to the clothing we wear every day, we can easily create a minimum safety device for neutron exposure," said Dr. Dae-Yoon Kim of KIST. "As Korea is developing very rapidly in the space and defense fields, we believe it will have great synergy." [Figure 1] Development of BNNT composite functional fibers for space radiation shielding / If continuous composite fibers containing high content of BNNTs are used as functional fabrics, they can effectively shield neutrons in space radiation to reduce harmful effects on human health and prevent soft errors in electronic devices. These functional fabrics are expected to play an important role in the fields of aviation, space, and national defense. [Figure 2] Development of BNNT composite continuous fibers / By overcoming the low dispersibility of BNNTs through interaction with aramid polymers, stable composite solutions can be prepared. This paves the way for the development of composite fibers that take advantage of the excellent properties of BNNTs and can be effectively utilized in various applications. [Figure 3] Applications of BNNT-based functional fabrics / The BNNT-based composite fibers can be manufactured into fabrics of various shapes and sizes through weaving. The developed fabrics can be utilized in clothing to protect astronauts, crew members, soldiers, firefighters, healthcare workers, and power plant workers who are expected to be exposed to radiation. The fabric can also be applied to electronic device packaging to prevent soft errors. ### 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 Yoo Sang-im) through the KIST K-Lab Project and Mid-Career Researcher Support Project (2021R1A2C2009423), the Ministry of Trade, Industry and Energy (Minister Ahn Deok-geun) through the High Performance Carbon Nanocomposite Fiber Development Project (RS202300258591), and the Ministry of Defense (Minister Shin Won-sik) through the Korea Research Institute for Defense Technology Planning and Advancement (DAPAKRITCT21014). The results of this research were published* in the latest issue of the international journal Advanced Fiber Materials (IF 17.2, JCR field 1.7%).

- Quantum error correction is a key technology in the implementation and practicalization of quantum computing - Groundbreaking quantum error correction technology contributes to the development of K-quantum computing deployments Solving the problem of error is essential for the practical application of quantum computing technologies that surpass the performance of digital computers. Information input into a qubit, the smallest unit of quantum computation, is quickly lost and error-prone. No matter how much we mitigate errors and improve the accuracy of qubit control, as the system size and computation scale increase, errors accumulate and algorithms become impossible to perform. Quantum error correction is a way to solve this problem. As the race for global supremacy in quantum technology intensifies, most major companies and research groups leading the development of quantum computing are now focusing on developing quantum error correction technology. Dr. Seung-Woo Lee and his team at the Quantum Technology Research Center at the Korea Institute of Science and Technology (KIST) have developed a world-class quantum error correction technology and designed a fault-tolerant quantum computing architecture based on it. They have demonstrated that this technology can outperform the quantum error correction technology recently developed by PsiQuantum, a global leader in the development of general-purpose quantum computers. The performance of universal quantum computing with quantum error correction is evaluated by its fault-tolerance threshold. This threshold indicates how well errors in quantum computing can be corrected, and the better the error correction technology and architectural design, the higher the value. PsiQuantum, an American quantum computer developer, has proposed a quantum computing architecture that utilizes photon entanglement resources, fusion techniques, and error correction technology, and is developing universal quantum computing hardware based on it. The photon loss threshold of the PsiQuantum method is reported to be 2.7%. The new error correction technique and quantum computing architecture developed by the KIST research team outperforms this. KIST's technology can achieve a photon loss threshold of up to 14%, which is currently the highest threshold in the world. In addition, KIST's error correction technique is much more resource-efficient than its quantum counterpart, even with the same photon consumption. The research is the first of its kind in Korea, and it is significant that Korea, a laggard in the field of quantum computing, has developed a world-class core technology. In particular, quantum error correction technology is an essential element in the development of quantum computers utilizing not only photon-based but also superconducting qubits, ion traps, and neutral atoms, which are highly competitive in R&D worldwide. This achievement shows that Korea has the potential to catch up with and even outpace the technology of leading countries in the quantum field. It is also expected to play an important role in building an independent quantum computing system by applying this achievement, which has completed domestic and international patent applications. "Just like semiconductor chip design technology, designing fault-tolerant architecture is important for quantum computing," said Dr. Seung-Woo Lee of KIST. Even if there are 1,000 physical qubits, it would be difficult to compute a single logical quantum task unless there is a structure that performs quantum error correction." 'The practicalization of quantum computing is still a long way off, but we believe that our research has contributed to bringing that time forward,' said Dr. Lee. [Figure 1] Fault-Tolerant Fusion-Based Quantum Computing Architecture with Quantum Error-Correcting Fusion / A fault-tolerant quantum computing architecture designed using quantum error-correcting encoded-fusion techniques. By adding layers of architecture, it utilizes multiple quantum error correction codes in fusion (Shor codes) and quantum computing architecture (Surface codes). [Figure 2] Photon Loss Tolerance Thresholds / Graph of photon loss tolerance threshold versus number of consumed photons compared to the results of PsiQuantum's method, Fusion-based Quantum Computing (FBQC). The encoded-fusion-based quantum computing (EFBQC) developed in this study achieves thresholds of up to 14%, significantly exceeding PsiQuantum's maximum threshold of 2.7%, and achieving significantly higher thresholds while consuming the same number of resources (photons). ### 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 Yoo Sang-im) under the KIST Major Project and Bilateral Technology Cooperation Project (2022M3K4A1094774). The research was published* on August 1 in the international journal Physical Review Letters (IF: 8.1 JCR field top 6.8%).

- Developing high-performance single-atom catalysts through chemical-free dry processes and computational science. - Rapid removal of bisphenol, an endocrine disruptor, in water treatment process Bisphenols are widely used as the main raw material for plastics such as receipts, water bottles, water containers, and vinyl due to their heat-resistant and mechanochemical properties. Among bisphenols, bisphenol A (BPA) that we often refer to as an "endocrine-disrupting chemicals" has been linked to adverse effects on reproduction, development, intelligence, and various metabolic diseases. Bisphenol F (BPF), a recently developed alternative to BPA Bisphenol A has also been reported in the literature to cause neurological disruption and various health risks. Dr. Jong Min Kim of the Materials Architecturing Research Center, Dr. Sang Soo Han of the Computational Science Research Center, Dr. Sang Hoon Kim of the Extreme Materials Research Center at Korea Institute of Science and Technology (KIST), and Professor Byeong-Kwon Ju of the School of Electrical Engineering at Korea University have fabricated high-performance cobalt single-atom catalysts through a chemical-free and environmentally friendly dry-based arc plasma deposition process. The team applied it to an electro-Fenton process based on electrochemical hydrogen peroxide synthesis to remove harmful bisphenols from aqueous solutions in a short time. The arc plasma process vaporizes metals or ceramics with repeated pulsed voltages in a vacuum, depositing them as a thin film on the surface of the substrates, and the number of pulses can be controlled to create a deposited layer with the desired thickness or properties. The cobalt single-atom catalyst fabricated by the arc plasma process exhibited the world's highest metal single-atom loading (2.24 wt%) compared to previously reported single-atom loading of dry processes (around 1 wt%). The coordination structure and active sites of the prepared Co single-atom catalyst were characterized by various material analyses including computational science, and electrochemical measurements confirmed that it is an excellent single-atom catalyst for electrochemical hydrogen peroxide production. The researchers applied the Co single-atom catalyst as an electrode to supply hydrogen peroxide in real time in the electro-Fenton water treatment process, and found that it could rapidly degrade 100% of BPF at a targeted concentration of 20 ppm in aqueous solution within 5 minutes. Through repeated experiments and wastewater treatment tests, the stability of the catalyst and the removal of bisphenol compounds were verified, and based on this, it is expected to be applied to the removal of emerging pollutants in wastewater treatment plants in large cities or specific industrial wastewater treatment facilities. "This achievement is significant in that we have produced high-performance single-atom catalysts in a dry process that does not use harmful chemicals and applied them to the water treatment field," said Dr. Jong Min Kim of KIST, while Dr. Sang Hoon Kim of KIST said, "Research on the production of metal nanoparticles by arc plasma deposition is widely known, but this is the first study to show that single-atom deposition is possible.“ [Figure 1] Schematic illustration of the synthetic process of Co single-atom catalyst using arc plasma deposition. [Figure 2] Images of a Co single-atom catalyst prepared using arc plasma deposition (APD) and comparison of loading amount of single atoms using a conventional dry process. [Figure 3] Identification of the active sites of electrochemical hydrogen peroxide production reaction on Co single-atom catalyst using computational science and its application to the rapid removal of bisphenol F (BPF), an organic pollutant, using electro-Fenton. [Figure 4] High-performance Co single-atom catalyst supported on carbon nanofibers developed by KIST researchers through a dry-based arc plasma deposition process. ### 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 KIST Major Project and Nanomaterial Technology Development Project (NRF-2022M3H4A7046278) and the Ministry of Environment. This research was published online on July 5 in the SCI journal Carbon Energy (IF: 19.5, JCR: 3.8%).

- KIST develops next-generation cooling material to increase summer cooling efficiency without electricity - Coloring materials for both design and energy savings Dr. Jin Gu, Kang and his team at the Nanophotonics Research Center at the Korea Institute of Science and Technology (KIST) have developed a colorful radiation-cooling liquid crystal material that can cool without external power while simultaneously emitting color. Radiative cooling is a powerless cooling technology that releases infrared radiation as heat through the atmospheric window to reduce temperatures. It is attracting attention as a next-generation eco-friendly cooling technology that can supplement power-hungry air conditioners. Radiative cooling materials for daytime use are colored white to reduce sunlight absorption. This provides excellent cooling performance but has the disadvantage that it cannot be used in buildings or vehicles that require aesthetics because it is difficult to implement multiple colors. Therefore, the development of colored radiative cooling materials that meet cooling and aesthetics at the same time has recently attracted attention. Previously known colored radiative cooling materials use light absorption to produce color, resulting in low temperature reduction. Alternative colored materials in the form of photonic crystals that use light reflection had excellent cooling performance but were limited in realizing distinct colors. The team solved this problem by fabricating bent spiral liquid crystal photonic crystals. The commercial liquid crystal (LC242) used in this study is not only a material that reduces its temperature through radiation cooling, but also forms colored photonic crystals through its periodic structure when aligned into a spiral using an inducer. The researchers used a spin coating process to bend these colored photonic crystals, resulting in vivid colors unlike conventional photonic crystals, which have different colors depending on the angle. By combining the fabricated colored radiation-cooling liquid crystal material with an upper transparent film and a lower metallic thin film, the team was able to achieve a temperature of about 30.8 °C lower than the same colored commercial paint and about 3.1 °C lower than ambient air in the middle of the day, the researchers said. The material could be used to reduce air conditioning consumption on the exterior of buildings and vehicles where aesthetics is a consideration, as well as to provide power-free cooling for outdoor leisure items and military tents. "The colored radiation-cooling liquid crystal material developed in this study can be quickly fabricated through a low-cost and simple spin coating process," said Dr. Jin Gu Kang, a professor at KIST. "If the large-scale commercialization of this technology is successful, it will be used for cooling a wide range of fields such as electronics and mobility in the future." [Figure 1] Schematic and real-world photos of colorful radiation-cooling liquid crystal material [Figure 2] Cooling performance of colorful radiative cooling liquid crystal materials [Figure 3] Fabrication schematic of the colorful radiation-cooled liquid crystal material [Figure 4] Postdoctoral researcher Minjeong Kim (left) and principal investigator Jin Gu Kang (right) show the colorful radiative cooling material they created in the process lab. [Figure 5] A research team prepares to measure radiative cooling performance in the outdoor experimental space on the roof of the research building. ### 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 KIST Institutional Program and the Ministry of Trade, Industry and Energy (Minister Ahn Duk-geun) (20213091010020). The research results were published* in the latest issue of the international journal Chemical Engineering Journal (IF: 13.3, top 3.1% in JCR).

- KIST researchers develop atomically controlled MXenes as water electrolysis catalyst support - Molybdenum-based MXene electrocatalyst support reduces the cost of green hydrogen production 137 countries around the world have signed a "net-zero" climate change agreement to end fossil fuel use and achieve zero carbon emissions by 2050. Hydrogen is being touted as the next green energy source because it emits only water and oxygen when utilized as an energy source. Hydrogen production methods are divided into gray hydrogen, blue hydrogen, and green hydrogen depending on the energy source and carbon emissions. Among them, green hydrogen production method is the most eco-friendly method that produces hydrogen without carbon emissions by electrolyzing water using green energy. A research team led by Dr. Albert Sung Soo Lee of the Convergence Research Center for Solutions to Electromagnetic Interference in Future-Mobility and Materials Architecturing Research Center at Korea Institute of Science and Technology (KIST) with collaboration with Professor Chong Min Koo’s group at Sungkyunkwan University has developed an oxidatively stable molybdenum-based MXene as electrocatalyst support in anion exchange membrane water electrolyzers. As it is stable against oxidative high voltage conditions, if it is applied as a carrier for electrolysis catalysts, it can be used as an oxygen evolution reaction electrode material for green hydrogen production to reduce the cost of green hydrogen production. The breakdown of water into hydrogen and oxygen molecules requires a high amount of energy. To reduce this initial reaction energy, a catalyst is used, and the smaller size of the catalyst, which is made up of tiny nanoscale particles, the larger the surface area, which allows the reaction to take place. However, over time, small catalyst particles can agglomerate, reducing the surface area and reducing the efficiency of hydrogen production. To prevent this, catalysts and supports are used together, and carbon is mainly used for the cathode, where hydrogen is produced, but when carbon is used in an oxidation reaction at the anode, it is oxidized to carbon dioxide. Thus a support with high oxidation resistance is required. One material that can be used as a support is MXene. MXenes are nanomaterials composed of metal atoms (Ti, Mo, Hf, Ta, etc.) and carbon or nitrogen atoms, which show electrically conductive properties and have a 2D nanostructure suitable for catalyst support, making them favorable for hydrogen production. Titanium-based MXenes have been the most widely studied due to their high electrical conductivity. However, due to the atomic nature of titanium, which is easily oxidized in water, has led to the inherent disadvantage that the catalyst cannot maintain high electrical conductivity. To overcome this, the team designed a new anode catalyst that uses molybdenum-carbide based MXene as a support. When the molybdenum-based MXene is utilized as a support, strong chemical bonds are created between the molybdenum atoms on the surface of the MXene and the active materials cobalt. The resulting chemical bonds increased the hydrogen production efficiency by about 2.45 times. In particular, the durability of the unit cell was improved by more than 10 times compared to the results of a recent titanium-based MXene, which lasted less than 40 hours. This is expected to reduce the cost of green hydrogen production and will be applied to large-scale hydrogen production plants and large-scale green hydrogen power stations in the future. "By controlling the elements that make up MXene, we were able to find suitable candidates for green hydrogen production environments, and through this, we secured a stable MXene support in an oxidizing environment," said Dr. Albert Sung Soo Lee of KIST. "In the future, we will contribute to the revitalization of hydrogen-based economy by developing oxygen-generating electrode catalysts with catalytic efficiency and durability." [Figure 1] Overall concept of catalyst design using MXene as an electrocatalyt support and its utilization as an electrode for an anion exchange membrane water electrolyzer. [Figure 2] Water electrolyzer device performance and durability as a function of catalyst utilizing various MXene supports [Figure 3] An electrode with a molybdenum MXene catalyst transferred onto an electrolyzer device. The cathode element, one of the key components of a hydrogen production device, is being held. [Figure 4] (Standing from left) Senior Research Scientist Dr. Albert Sung Soo Lee, Postdoctoral Researcher Gwan-Hyun Choi, and (Sitting) Student Researcher Young Sang Park at KIST. ### 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 National Research Council of Science and Technology (NST) grant by the Korea Government (MSIT) (CRC22031-000), Ministry of Science and ICT (Minister Lee Jong-Ho) under the Basic Science Research Program, as well as and KIST Young Fellow Program. These findings were published in the latest issue of the international journal Applied Catalysis B: Environment and Energy (IF: 20.2, top 0.6% in JCR).