KAIST, Production Temperature ↓ by 500°C, Power Output ↑ 2x… Next-Generation Ceramic Electrochemical Cell Reborn
<(Top row, from left) Professor Kang Taek Lee, Ph.D candidate Yejin Kang, Dr. Dongyeon Kim, (Bottom row, from left) M.S candidate Mincheol Lee, Ph.D candidate Seeun Oh, Ph.D candidate Seungsoo Jang, Ph.D candidate Hyeonggeun Kim>
As power demand surges in the AI era, the “protonic ceramic electrochemical cell (PCEC),” which can simultaneously produce electricity and hydrogen, is gaining attention as a next-generation energy technology. However, this cell has faced the technical limitation of requiring an ultra-high production temperature of 1,500°C. A KAIST research team has succeeded in establishing a new manufacturing process that lowers this limit by more than 500°C for the first time in the world.
KAIST (President Kwang Hyung Lee) announced on the 4th of December that Professor Kang Taek Lee’s research team in the Department of Mechanical Engineering developed a new process that enables the fabrication of high-performance protonic ceramic electrochemical cells at temperatures more than 500°C lower than before, using “microwave + vapor control technology” that leverages microwave heating principles and the diffusion environment of chemical vapor generated from specific chemical components.
The electrolyte—the key material of protonic ceramic electrochemical cells—contains barium (Ba), and barium easily evaporates at temperatures above 1,500°C, which has been the main cause of performance degradation. Therefore, the ability to harden the ceramic electrolyte at a lower temperature has been the core issue that determines cell performance.
As power demand surges in the AI era, the “protonic ceramic electrochemical cell (PCEC),” which can simultaneously produce electricity and hydrogen, is gaining attention as a next-generation energy technology. However, this cell has faced the technical limitation of requiring an ultra-high production temperature of 1,500°C. A KAIST research team has succeeded in establishing a new manufacturing process that lowers this limit by more than 500°C for the first time in the world.
KAIST (President Kwang Hyung Lee) announced on the 4th of December that Professor Kang Taek Lee’s research team in the Department of Mechanical Engineering developed a new process that enables the fabrication of high-performance protonic ceramic electrochemical cells at temperatures more than 500°C lower than before, using “microwave + vapor control technology” that leverages microwave heating principles and the diffusion environment of chemical vapor generated from specific chemical components.
The electrolyte—the key material of protonic ceramic electrochemical cells—contains barium (Ba), and barium easily evaporates at temperatures above 1,500°C, which has been the main cause of performance degradation. Therefore, the ability to harden the ceramic electrolyte at a lower temperature has been the core issue that determines cell performance.
To solve this, the research team devised a new heat-treatment method called “vapor-phase diffusion.” This technique places a special auxiliary material (a vapor source) next to the cell and irradiates it with microwaves to quickly diffuse vapor. When the temperature reaches approximately 800°C, the vapor released from the auxiliary material moves toward the electrolyte and tightly bonds the ceramic particles. Thanks to this technology, a process that previously required 1,500°C can now be completed at just 980°C. In other words, a world-first ceramic electrochemical cell fabrication technology has been created that produces high-performance electricity at a “low temperature” without damaging the electrolyte.
A cell fabricated with this process produced 2 W of power stably from a 1 cm² cell (roughly the size of a fingernail) at 600°C and generated 205 mL of hydrogen per hour at 600°C (about the volume of a small paper cup, among the highest in the industry). It also maintained stability without performance degradation during 500 hours of continuous operation.
In other words, this technology reduces the production temperature (−500°C), lowers the operating temperature (600°C), doubles performance (2 W/cm²), and extends the lifespan (500-hour stability), achieving world-class performance in ceramic cell technology.
The research team also enhanced the reliability of the technology by using digital twins (virtual simulations) to analyze gas-transport phenomena occurring in the microscopic internal structure of the cell − phenomena that are difficult to observe in actual experiments.
<Figure 1. (a) Schematic of the vapor-diffusion-based process; (b) Surface microstructure of the electrolyte; (c) Internal barium composition ratio of the electrolyte according to processing conditions; (d) Comparison of power-generation performance with previous studies>
< Figure 2. (a) Three-dimensional reconstructed image of the protonic ceramic electrochemical cell fuel electrode according to processing conditions (b) Pore structure (c) Gas-transport simulation results >
Professor Kang Taek Lee emphasized, “This study is the world’s first case of using vapor to lower the heat-treatment temperature by more than 500°C while still producing a high-performance, high-stability cell.” He added, “It is expected to become a key manufacturing technology that addresses the power challenges of the AI era and accelerates the hydrogen society.”
Dongyeon Kim (KAIST PhD) and Yejin Kang (KAIST PhD candidate) participated as co–first authors. The research results were published in Advanced Materials (IF: 26.8), one of the world’s leading journals in energy and materials science, and were selected as the Inside Front Cover article on October 29.
(Paper title: “Sub-1000°C Sintering of Protonic Ceramic Electrochemical Cells via Microwave-Driven Vapor Phase Diffusion,” DOI: https://doi.org/10.1002/adma.202506905)
This research was supported by the MSIT’s Mid-career Researcher Program and the H2 Next Round Program.
Success in Measuring Nano Droplets, A New Breakthrough in Hydrogen, Semiconductor, and Battery Research
<(From Left) Ph.D candidate Uichang Jeong, Professor Seungbum Hong>
In hydrogen production catalysts, water droplets must detach easily from the surface to prevent blockage by bubbles, allowing for faster hydrogen generation. In semiconductor manufacturing, the quality of the process is determined by how evenly water or liquid spreads on the surface, or how quickly it dries. However, directly observing how such water or liquid spreads and moves on a surface ('wettability') at the nanoscale has been technically almost impossible until now, forcing researchers to rely mostly on conjecture. KAIST announced on December 2nd that a research team led by Professor Seungbum Hong of the Department of Materials Science and Engineering, in collaboration with Professor Jongwoo Lim's team at Seoul National University, has developed a technology to directly observe nano-sized water droplets in real-time using an Atomic Force Microscope (AFM) and to calculate the contact angle based on the droplet's shape. This research, by enabling the visual confirmation of the actual shape of nano-droplets, allows for the precise analysis of how well water droplets adhere to and detach from a surface. This is expected to be immediately applicable to various advanced technologies where liquid movement determines performance, such as hydrogen production catalysts, fuel cells, batteries, and semiconductor processes. Recently, precise measurement at the nanoscale has become crucial for wettability analysis technology. Traditional methods using large water droplets, several millimeters in size, could distinguish between hydrophilicity (where water spreads easily) and hydrophobicity (where water doesn't spread easily) on the surface. However, at the nanoscale, the droplets are too small to directly observe their shape. The research team successfully induced nano-droplets to form naturally by gently cooling the surface to a temperature where atmospheric water vapor does not freeze. They then observed these droplets using the non-contact mode of the AFM to capture their original shape. Since nano-droplets are sensitive and can be deformed by mere contact with the probe, precise control is essential. Furthermore, when the team applied this technique to the ferroelectric material lithium tantalate, they were the first to confirm a difference in the nano-droplet contact angle depending on the material's electrical direction (polarization). This difference, which was not visible with large droplets, demonstrates that nano-droplets are highly sensitive to the electrical state of the surface. The team then applied this technology to the water electrolysis catalyst used in hydrogen production, observing a single nano-droplet. This result aids in understanding how water reacts on the catalyst surface and can be used to analyze catalyst performance, particularly how well bubbles detach.
<Figure 1. Nanoscale droplet visualization using non-contact mode>
<Figure 2. Single-droplet visualization formed on sub-micron-sized water-splitting catalyst LiFeLDH particles>
Professor Seungbum Hong stated, "This research is an important case demonstrating that the Atomic Force Microscope can be used to directly visualize nano-sized water droplets and even measure the contact angle. Being able to observe the behavior of water droplets in the nano-world, which was previously invisible, will establish this as a core analysis technology for the development of next-generation energy and electronic materials." This research, in which Uichang Jeong, a PhD candidate in the KAIST Department of Materials Science and Engineering, participated as the first author, was published on October 17th in 'ACS Applied Materials and Interfaces', a prestigious journal in the field of new materials and chemical engineering published by the American Chemical Society (ACS).
Paper Title: Nanoscale Visualization and Contact Angle Analysis of Water Droplets on Ferroelectric Materials
DOI: https://doi.org/10.1021/acsami.5c14404
This research was supported by the Ministry of Science and ICT and the National Research Foundation of Korea.
KAIST Confirms Reduction of Amyloid-β Using Red OLED-Restores Memory in Alzheimer’s Model
<Professor Kyung Cheol Choi, Dr. Byeongju Noh, Ph.D candidate Young-Hun Jung, Ph.D candidate Minwoo Park, Dr.Ja Wook Koo, Researcher Jiyun Lee, Researcher Ji-Eun Lee, Dr. Hyang Sook Hoe, Dr. Hyun-Ju Lee, Dr. Sora Kang, Researcher Seokjun Oh>
A Korean research team, raising the question “Which OLED light color can actually improve memory and pathological markers in Alzheimer’s patients?”, has identified the most effective OLED color capable of enhancing cognitive function using only light—with no drugs involved. The OLED platform developed for this study can precisely control color, brightness, flicker frequency, and exposure duration, suggesting potential future development into personalized OLED-based electroceuticals.
On the 24th, KAIST (President Kwang Hyung Lee) announced that a joint research team led by Professor Kyung Cheol Choi from the School of Electrical Engineering at KAIST and Dr. Ja Wook Koo and Dr. Hyang Sook Hoe from the Korea Brain Research Institute (KBRI) developed a uniform-illuminance, three-color OLED photostimulation technology and confirmed that “red 40-Hz light” was the most effective among blue, green, and red in improving Alzheimer's pathology and memory function.
To overcome the structural limitations of conventional LEDs—such as brightness imbalance, heat generation risk, and variability caused by animal movement—the researchers developed an OLED-based photostimulation platform that emits light uniformly. Using this platform, they compared white, red, green, and blue light under identical conditions (40-Hz frequency, brightness, and exposure time) and found that red 40-Hz light produced the most significant improvement.
In an early-stage (3-month-old) Alzheimer’s animal model, improvement in pathology and memory was observed after only two days of stimulation. When early Alzheimer’s model mice were exposed to one hour of light per day for two days, both white and red light improved long-term memory. Additionally, the amount of amyloid-β (Aβ) plaques—protein aggregates known as a major factor in Alzheimer’s disease—was reduced in key brain regions such as the hippocampus, and levels of the plaque-clearing enzyme ADAM17 increased.
This indicates that even very short periods of light stimulation can reduce harmful proteins in the brain and improve memory function. In particular, with red light, the inflammatory cytokine IL-1β, known to exacerbate inflammation and contribute to Alzheimer’s progression, decreased significantly, demonstrating an anti-inflammatory effect.
Moreover, the more plaque was reduced, the greater the improvement in memory—direct evidence that pathological improvement leads to cognitive enhancement.
In the mid-stage (6-month-old) Alzheimer’s model, statistically significant pathological improvement was seen only with red light. In a two-week long-term stimulation experiment under the same conditions, both white and red light improved memory, but a statistically meaningful reduction in plaques appeared only under red light.
< The mechanism by which red OLED stimulation of neurons reduces amyloid-β in Alzheimer’s model mice >
Differences at the molecular level were also clear. Under red light, levels of ADAM17 (which helps remove plaques) increased, while levels of BACE1, an enzyme responsible for producing plaques, decreased—demonstrating a dual effect of both inhibiting plaque formation and promoting plaque removal. In contrast, white light only lowered BACE1, showing more limited therapeutic effects compared to red light.
This scientifically identifies that the color of light is a key factor determining therapeutic efficacy.
To determine which neural circuits were activated by light stimulation, the team analyzed the expression of c-Fos, an immediate-early gene that is activated when neurons fire.
They found activation throughout the visual–memory circuit, extending from the visual cortex → thalamus → hippocampus, providing direct neurological evidence that light stimulation awakens the visual pathway, enhancing hippocampal function and memory.
Thanks to the uniform-illuminance OLED platform, light was evenly delivered regardless of animal movement, ensuring stable experimental results and high reproducibility across repeated tests.
This study is the first to demonstrate that cognitive function can be improved using only light, without drugs, and that Alzheimer’s pathological markers can be regulated through combinations of light color, frequency, and duration.
The OLED platform developed in this study allows fine control over color, brightness, flicker ratio, and exposure time, making it suitable for personalized stimulation design in future human clinical research.
The research team plans to expand conditions such as stimulation intensity, energy, duration, and combined visual–auditory stimulation, aiming toward clinical-stage development.
Dr. Byeongju Noh (from Professor Kyung Cheol Choi’s research team) said, “This study experimentally demonstrates the importance of color standardization and confirms that red OLED is the key color that activates ADAM17 and suppresses BACE1 across disease stages.”
Professor Kyung Cheol Choi emphasized, “Our uniform-illuminance OLED platform overcomes the structural limitations of traditional LEDs and enables high reproducibility and safe evaluation. We expect wearable RED OLED electroceuticals for everyday use to present a new therapeutic paradigm for Alzheimer’s disease.”
The research findings were published online on October 25 in ACS Biomaterials Science & Engineering, a leading international journal in biomedical and materials science.
Paper Title: Color Dependence of OLED Phototherapy for Cognitive Function and Beta-Amyloid Reduction through ADAM17 and BACE1
DOI: https://pubs.acs.org/doi/full/10.1021/acsbiomaterials.5c01162
Co-authors:Byeongju Noh, Hyun-Ju Lee, Jiyun Lee, Jiyun Lee, Ji-Eun Lee, Bitna Joo, Young-Hun Jung, Minwoo Park, Sora Kang, Seokjun Oh, Jeong-Woo Hwang, Dae-Si Kang, Yongmin Jeon, So-Min Lee, Hyang Sook Hoe, Ja Wook Koo, Kyung Cheol Choi
This research was supported by the National Research Foundation of Korea and the National IT Industry Promotion Agency under the Ministry of Science and ICT, and the Korea Brain Research Institute Basic Research Program. (2017R1A5A1014708, 2022M3E5E9018226, H0501-25-1001, 25-BR-02-02, 25-BR-02-04)
Depression is Not Only a Disease of the Mind. KAIST Discovers the Immune-Brain Connection
<(From Left) Ph.D candidate Insook Ahn from KAIST, Professor Jinju Han from KAIST, (Upper Left) Yangsik Kim from Inhan University School of Medicine, Ph.D candidate Soyeon Chang(psychiatrist)>
Major depressive disorder (MDD) is characterized by a lowered mood and loss of interest, contributing not only to difficulties in academic and professional life but also as a major cause of suicide in South Korea. However, there are currently no objective biological markers that can be used for diagnosis or treatment. Amidst this, a research team from KAIST has revealed that depression is not merely a problem of the mind or brain, but is deeply connected to abnormalities in the body's overall immune response. They found that this immune abnormality affects brain function, and the 'Immune Neural Axis' imbalance is the core mechanism of depression, opening up the possibility for the discovery of new biomarkers and the development of new drugs for depression treatment.
KAIST announced on the November 20th that Professor Jinju Han's research team from the Graduate School of Medical Science and Engineering (GSMSE) at KAIST, in collaboration with Professor Yangsik Kim's research team (Ph.D., KAIST GSMSE) from Inha University School of Medicine, performed a multi-omics analysis combining plasma proteomic analysis, WBC single-cell analysis, and patient-derived brain organoids (mini-brains). This study focused on female patients with MDD who exhibited 'Atypical Features' (such as hypersomnia and overeating) and 'Psychotic Symptoms'(such as auditory hallucinations and idea of reference), which are different from typical depression symptoms, and who also had impaired reality judgment.
Sduio
■ "Immune Cells and Brain Function are Altered Together" A New Biological Clue for Depression
The research team simultaneously examined genetic changes in immune cells in the blood and changes in nervous-system-related proteins. The results confirmed a breakdown in the balance of immune-neural interaction in patients with depression.
MDD, especially in young women, often presents with atypical symptoms (hypersomnia, overeating, mood reactivity, etc.), which increases the risk of a later diagnosis of bipolar disorder. Furthermore, about 40% of patients are classified as treatment-resistant depression, showing no response to various antidepressants.
Consequently, there has been a continuous call for the development of new therapeutic strategies and the discovery of biomarkers based on immunity and metabolism, moving beyond the traditional drug-centric approach.
■ World's First Integration of "Leukocyte Single-Cell Analysis + Brain Organoid" A New Paradigm for Psychiatric Research
The research team presented the world's first precision medicine approach by integrating plasma proteomics, leukocyte single-cell transcriptome analysis, and analysis of brain organoids created from patient-derived induced pluripotent stem cells (iPSCs).
The results showed that patients with atypical depression exhibited high levels of stress, anxiety, and depression. Furthermore, proteins crucial for inter-neuronal signaling (DCLK3 and CALY) were significantly elevated compared to normal levels, and Complement Protein C5, which strongly enhances the body's immune response, was also increased. This indicates that both 'brain function' and 'immune function' are excessively activated and out of balance within the body.
This finding confirms a clue that depression is not merely a mood issue but is connected to biological changes occurring throughout the entire body. Upon examining the immune cells of depression patients, genetic changes were found that make inflammatory responses in the body occur more easily and strongly than usual. This implies that the entire bodily immune system is in a state of excessive activation, and this immune/inflammatory abnormality may influence the development of depression.
The patient-derived brain organoids showed accompanying growth retardation and abnormal neural development, supporting the possibility that immune abnormalities interact with changes in brain function to exacerbate the disease.
■ "Immune-Neural Axis Imbalance is the Core Mechanism of Atypical Depression"
This study integrated clinical data, single-cell omics, proteomics, and brain organoids to demonstrate that the 'Imbalance of the Immune-Neural Axis' is the core mechanism of MDD accompanied by atypical and psychotic symptoms.
<Integration of clinical symptoms, blood analysis, and patient-derived brain organoid analysis in women with major depressive disorder>
Professor Jinju Han stated, "This achievement presents a new precision medicine model for psychiatric research," adding, "We anticipate that this will actively lead to biomarker discovery and new drug development."
This accomplishment was published online in the world-renowned international scientific journal, Advanced Science, on October 31st.
※ Paper Title: Exploration of Novel Biomarkers through a Precision Medicine Approach Using Multi-omics and Brain Organoids in Patients with Atypical Depression and Psychotic Symptoms DOI: https://doi.org/10.1002/advs.202508383
※ Author Information: Soyeon Chang (Inha University, Co-First Author), Seok-Ho Choi, Jiyoung Lee, Yangsik Kim (Inha University, Corresponding Author), Insook Ahn (KAIST, Co-First Author), and Jinju Han (KAIST, Corresponding Author)
This research was supported by the National Research Foundation of Korea and the Korea Health Industry Development Institute.
A KAIST team develops the world's first modular co-culture platform for the one-pot production of rainbow-colored bacterial cellulose.
<(From Left) Distinguished Professor Sang Yup Lee, Ph.D candidate Pingxin Lin, Ph.D candiate Zhou Hengrui>
The integration of systems metabolic engineering with co-culture strategies that couples bacterial cellulose production with natural colorant biosynthesis enabled the one-pot generation of rainbow-colored bacterial cellulose, establishing a sustainable biomanufacturing platform that can replace petroleum-based textiles and eliminate chemical dyeing processes.
A research group at KAIST has successfully developed a modular co-culture platform for the one-pot production of rainbow-colored bacterial cellulose. The team, led by Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering, engineered Komagataeibacter xylinus for bacterial cellulose synthesis and Escherichia coli for natural colorants overproduction. A co-culture of these engineered strains enabled the in situ coloration of bacterial cellulose. This research offers a versatile platform for producing living materials in multiple colors, and provides new opportunities for sustainable textiles, wearable biomaterials, and functional living materials that combine optical and structural properties beyond the reach of conventional textile technologies.
Bacterial cellulose is an attractive and biodegradable alternative to petroleum-derived fabrics due to its high purity, mechanical strength, and water-retention properties. However, the limited color range of bacterial cellulose, which is typically white, has limited its broader application in the textile industry, where more vibrant colored fabrics are increasingly desired. Conventional dyeing methods rely on petroleum-based colorants and toxic reagents, creating environmental and processing challenges. These challenges have driven the demand for alternative production methods.
To address these issues, KAIST researchers, including Ph.D. Candidate Hengrui Zhou, Ph.D. Candidate Pingxin Lin, Professor Ki Jun Jeong, and Distinguished Professor Sang Yup Lee, combined systems metabolic engineering with co-culture strategies to develop a bio-based route that integrates bacterial cellulose formation with natural pigment synthesis, enabling the production of colored living materials in a single step without additional chemical processing.
The team’s work, entitled “One-pot production of colored bacterial cellulose,” was published in Trends in Biotechnology on November 12,2025.
This research details the one-pot production of multicolored bacterial cellulose using a modular co-culture platform that integrates a bacterial cellulose-overproducing K. xylinus strain with natural colorant-producing E. coli strains. The team focused on addressing the limitations in bacterial cellulose coloration caused by environmental challenges and complex processing requirements. By employing vesicle engineering and optimizing co-culture parameters, the researchers achieved one-pot production of red, orange, yellow, green, blue, navy, and purple bacterial cellulose, eliminating the need for external dyes and toxic chemical treatments.
To enhance dyeing efficiency, E. coli strains were engineered for the overproduction and secretion of natural colorants. It was determined that the intracellular accumulation of these pigments disrupts cellular metabolism and physiology, thereby inhibiting their production. To overcome this limitation, vesicle engineering has emerged as a key strategy to mitigate these cytotoxic effects, including the induction of inner- and outer-membrane vesicles and the modulation of cell morphology, enabling the more efficient secretion of colorants and increased overall production. The engineered E. coli strains were optimized in fed-batch fermentation, achieving record-breaking production of 16.92 ± 0.10 g/L of deoxyviolacein, 8.09 ± 0.17 g/L of violacein, 1.82 ± 0.07 g/L of proviolacein, and 936.25 ± 9.70 mg/L of prodeoxyviolacein, the highest reported titers to date for all four violacein derivatives.
< Figure 1. Rainbow-colored bacterial cellulose (microbial fiber) with applied color >
A co-culture platform combining the K. xylinus with E. coli strains was further developed and optimized, enabling the in situ one-pot coloration of bacterial cellulose in vibrant green, blue, navy, and purple. Fed-batch fermentation further improved the performance of the platform, achieving the world-first one-pot production of multicolored bacterial cellulose on a larger scale. To expand the bacterial cellulose color palette, engineered carotenoid-producing E. coli strains were incorporated, enabling the successful synthesis of red, orange, and yellow bacterial cellulose. This milestone demonstrates the potential of microbial fermentation as a sustainable alternative to petroleum-based textile processes.
“We can anticipate that this microbial cell factory-based one-pot production of rainbow-colored bacterial cellulose has the potential to replace current petroleum-based textile processes,” said Ph.D. Candidate Hengrui Zhou. “The systems metabolic engineering strategies developed in this study could be broadly applied for the production of diverse sustainable textiles, wearable biomaterials, and functional living materials that combine optical and structural properties beyond the capabilities of conventional textile technologies.” He added, “This platform reduces the environmental impact while greatly expanding design possibilities. Beyond serving as a proof-of-concept, this technology offers a promising route toward scalable, eco-friendly fabrics with in situ coloration. Its modular design allows the incorporation of diverse natural colorant pathways, enabling the creation of living materials in multiple colors.”
< Figure 2. Schematic of a microbe-based platform for one-step production of rainbow-colored bacterial cellulose >
“As demand for sustainable textiles and living materials continues to grow, we expect that the integrated biomanufacturing platform developed here will play a pivotal role in producing diverse functional biomaterials with additional design possibilities in a single step, without additional chemical processing,” explained Distinguished Professor Sang Yup Lee.
This work was supported by the Development of Next-generation Biorefinery Platform Technologies for Leading Bio-based Chemicals Industry project (2022M3J5A1056072) and the Development of Platform Technologies of Microbial Cell Factories for the Next-generation Biorefineries project (2022M3J5A1056117) from the National Research Foundation supported by the Korean Ministry of Science and ICT.
Source:
Hengrui Zhou (1st), Pingxin Lin (2nd), Ki Jun Jeong (3rd), and Sang Yup Lee (Corresponding). “One-pot production of colored bacterial cellulose”. Trends in Biotechnology (Published) doi: 10.1016/j.tibtech.2025.09.019
Makes Summer Cooler and Winter Warmer Without Power
<(Front row from left)Professor Young Min Song, Ph.D candidate Hyung Rae Kim, M.S candidate Hyunkyu Kwak, (Back row from left)Ph.D candidate Hyo Eun Jeong, Dr. Sehui Chang, Ph.D candidate Do Hyeon Kim, (Circle from left) Professor Dae-Hyeong Kim, Dr. Yoonsoo Shin, Dr. Se-Yeon Heo>
The poplar (Populus alba) has a unique survival strategy: when exposed to hot and dry conditions, it curls its leaves to expose the ventral surface, reflecting sunlight, and at night, the moisture condensed on the leaf surface releases latent heat to prevent frost damage. Plants have evolved such intricate mechanisms in response to dynamic environmental fluctuations in diurnal and seasonal temperature cycles, light intensity, and humidity, but there have been few instances of realizing such a sophisticated thermal management system with artificial materials. Through this research, the KAIST research team has developed an artificial material that mimics the thermal management strategy of the poplar leaf, significantly increasing the applicability of power-free, self-regulating thermal management technology in applications such as building facades, roofs, and temporary shelters.
KAIST announced on November 18 that the research team led by Professor Young Min Song of the School of Electrical Engineering, in collaboration with Professor Dae-Hyeong Kim’s team at Seoul National University, has developed a flexible hydrogel-based ‘Latent-Radiative Thermostat (LRT)’ that mimics the natural heat regulation strategy of the poplar leaf.
The LRT developed by the research team is a bio-inspired thermal regulator that autonomously switches between cooling and heating modes. This technology is a new thermal management technique that can simultaneously realize latent heat regulation through the evaporation and condensation of water, and radiative heat regulation using light reflection and transmission, all within a single device.
The primary functional material is a composite that integrates lithium ions (Li+) and hydroxypropyl cellulose (HPC) within a polyacrylamide (PAAm) hydrogel. Li+ maintains warmth by condensing and absorbing moisture to regulate latent heat, and HPC changes between transparent and opaque states according to temperature changes, regulating the reflection and absorption of sunlight to switch between cooling and heating modes.
When the temperature rises, HPC molecules aggregate, causing the hydrogel to become opaque, which reflects sunlight and strengthens the natural cooling effect. The resulting LRT automatically switches among four thermal management modes based on the surrounding temperature, humidity, and sunlight.
<Figure 1. Schematic of a hydrogel-based self-regulating temperature controller inspired by the thermal management strategy of poplar leaves.>
▶ In night/cold environments below the dew point temperature, it maintains warmth by absorbing and condensing moisture in the air and releasing heat. ▶ On cold days with weak sunlight, it transmits sunlight and the absorbed moisture absorbs near-infrared radiation to produce a heating effect. ▶ In hot and dry conditions, internal moisture evaporates, resulting in powerful evaporative cooling. ▶ Under strong sunlight and high-temperature conditions, the HPC becomes opaque to reflect sunlight, and simultaneously, evaporative cooling operates to lower the temperature. That is, it is a bioinspired thermal management device that autonomously switches between cooling and heating modes according to the surrounding environment without requiring power.
Through this research, the LRT has demonstrated the performance to stay cooler in the summer and warmer in the winter. The research team confirmed that the thermal regulation properties can be finely tuned to various climate conditions by adjusting the concentrations of Li+ and HPC, and the durability and mechanical strength of the material were significantly improved by adding TiO2 nanoparticles. In outdoor experiments, the LRT maintained temperatures up to 3.7 °C lower in the summer and up to 3.5 °C higher in the winter compared to conventional cooling materials. Furthermore, a simulation covering 7 climate zones (ASHRAE standards) showed an annual energy saving of up to 153 MJ/m2 compared to existing roof coatings. This study is a case of the engineering implementation of the sophisticated thermal management strategies observed in nature. It is anticipated to serve as a next-generation thermal management platform for environments where power-based cooling and heating are difficult, such as building facades, roofs, and temporary shelters.
<Figure 2. Outdoor temperature measurement results and simulated energy savings.>
In a statement, Professor Young Min Song said, “This research is significant as it technically reproduced nature's intelligent thermal regulation strategy, presenting a thermal management device that self-adapts to seasonal and climate changes. It can be expanded into an intelligent thermal management platform applicable to various environments in the future.” This study was co-first authored by PhD candidate Hyung Rae Kim (School of Electrical Engineering, KAIST). Professor Young Min Song (School of Electrical Engineering, KAIST) participated as a corresponding author. The research was published online on November 4th in Advanced Materials (IF 26.8), a world-leading journal in the field of material science.
※ Paper Title: Hydrogel Thermostat Inspired by Photoprotective Foliage Using Latent and Radiative Heat Control, DOI: https://doi.org/10.1002/adma.202516537
This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (RS-2025-16063568, RS-2025-16902996, RS-2023-NR077254, RS-2022-NR068140). This work was supported by the InnoCORE program of the Ministry of Science and ICT(GIST InnoCORE KH0830). This work also was supported by the Technology Innovation Program(or Industrial Strategic Technology Development Program-Bio-industry Technology Development Project)(RS-2024-00467230, Development of a Digital Healthcare Device for Non-invasive Continuous Monitoring of Myocardial Infarction Biomarkers Based on Mid-Infrared Nano-Optical Filters) funded By the Ministry of Trade Industry & Energy(MOTIE, Korea)
3D Worlds from Just a Few Phone Photos
<(From Left) Ph.D candidate Jumin Lee, Ph.D candidate Woo Jae Kim, Ph.D candidate Youngju Na, Ph.D candidate Kyu Beom Han, Professor Sung-eui Yoon>
Existing 3D scene reconstructions require a cumbersome process of precisely measuring physical spaces with LiDAR or 3D scanners, or correcting thousands of photos along with camera pose information. The research team at KAIST has overcome these limitations and introduced a technology enabling the reconstruction of 3D —from tabletop objects to outdoor scenes—with just two to three ordinary photographs. The breakthrough suggests a new paradigm in which spaces captured by camera can be immediately transformed into virtual environments.
KAIST announced on November 6 that the research team led by Professor Sung-Eui Yoon from the School of Computing has developed a new technology called SHARE (Shape-Ray Estimation), which can reconstruct high-quality 3D scenes using only ordinary images, without precise camera pose information.
Existing 3D reconstruction technology has been limited by the requirement of precise camera position and orientation information at the time of shooting to reproduce 3D scenes from a small number of images. This has necessitated specialized equipment or complex calibration processes, making real-world applications difficult and slowing widespread adoption.
To solve these problems, the research team developed a technology that constructs accurate 3D models by simultaneously estimating the 3D scene and the camera orientation using just two to three standard photographs. The technology has been recognized for its high efficiency and versatility, enabling rapid and precise reconstruction in real-world environments without additional training or complex calibration processes.
While existing methods calculate 3D structures from known camera poses, SHARE autonomously extracts spatial information from images themselves and infers both camera pose and scene structure. This enables stable 3D reconstruction without shape distortion by aligning multiple images taken from different positions into a single unified space.
<Representative Image of SHARE Technology>
"The SHARE technology is a breakthrough that dramatically lowers the barrier to entry for 3D reconstruction,” said Professor Sung-Eui Yoon. “It will enable the creation of high-quality content in various industries such as construction, media, and gaming using only a smartphone camera. It also has diverse application possibilities, such as building low-cost simulation environments in the fields of robotics and autonomous driving."
<SHARE Technology, Precise Camera Information and 3D Scene Prediction Technology>
Ph.D. Candidate Youngju Na and M.S candidate Taeyeon Kim participated as co-first authors on the research. The results were presented on September 17th at the IEEE International Conference on Image Processing (ICIP 2025), where the paper received the Best Student Paper Award.
The award, given to only one paper among 643 accepted papers this year—a selection rate of 0.16 percent—once again underscores the excellent research capabilities of the KAIST research team.
Paper Title: Pose-free 3D Gaussian Splatting via Shape-Ray Estimation, DOI: https://arxiv.org/abs/2505.22978
Award Information: https://www.linkedin.com/posts/ieeeicip_congratulations-to-the-icip-2025-best-activity-7374146976449335297-6hXz
This achievement was carried out with support from the Ministry of Science and ICT's SW Star Lab Project under the task 'Development of Perception, Action, and Interaction Algorithms for Unspecified Environments for Open World Robot Services.'
IEEE President Professor Kramer Holds Special Lecture on Artificial Intelligence in the Electrical Engineering Department
Kathleen A. Kramer, President of the IEEE (Institute of Electrical and Electronics Engineers), the world's largest technical professional organization dedicated to electrical and electronic technology, visited our university on the 30th and delivered a special lecture under the theme, 'Drawing the Future of Artificial Intelligence Together.'
< IEEE Leadership and KAIST EE Meeting KITIS Director (Sung-Hyun Hong), KAIST EE Professors (Joonwoo Bae), (Ian Oakley), (Hye-Won Jeong), (Chang-Shik Choi), (Dong-Soo Han), Head of EE Department (Seunghyup Yoo), IEEE President (Kathleen A. Kramer), IEEE Senior Sales Director (Francis Staples), IEEE Regional Manager for APAC (Ira Tan), KAIST EE Professor (Hee-Jin Ahn), Head of Semiconductor System Engineering Department (Sung-Hwan Cho)>
Standing at the colloquium podium by invitation of the Department of Electrical Engineering (Head: Seung-Hyup Yoo), President Kramer emphasized based on IEEE's core vision, 'Advancing Technology for Humanity,' that "Artificial Intelligence (AI) is no longer a concept of the distant future; it has become a technology that is transforming human lives at the center of innovation."
< Photo of IEEE President's KAIST EE Colloquium Lecture >
She further added, "Technology must advance with human values at its core, and AI based on ethics and inclusiveness can lead to true innovation," sharing her insights on the direction of AI development and the social responsibility of technology.
Seung-Hyup Yoo, Head of the Department of Electrical Engineering, stated, "We expect President Kramer's visit to be a stepping stone that will not only widely promote our department's capabilities in advanced fields such as AI, semiconductors, signal processing, and robotics to the international academic community but also strengthen cooperation in various ways."
< Tea Meeting with the IEEE Leadership and the Vice Presidents . KITIS Director (Sung-Hyun Hong), IEEE Senior Sales Director (Francis Staples), IEEE President (Kathleen A. Kramer), KAIST Executive Vice President for Research (Sang Yup Lee), Head of EE Department (Seunghyup Yoo), IEEE Regional Manager for APAC (Ira Tan)>
Meanwhile, prior to the lecture, President Kramer paid a courtesy visit to Sang-Yup Lee, KAIST Executive Vice President for Research, and reaffirmed the commitment of both organizations to advancing sustainable technology and building an ethical and inclusive research ecosystem to contribute to a better life for humanity.
KAIST Uncovers the Mechanism Behind Overactive Immune Cells
<(From Right) Professor Eui-Cheol Shin, Ph.D candidate So-Young Kim, Professor Su-Hyung Park, Professor Hyuk Soo Eun, Dr. Hoyoung Lee>
“Why do immune cells that are supposed to eliminate viruses suddenly turn against our own body?”
There are instances where killer T cells—which are meant to precisely remove virus-infected cells—malfunction like overheated engines, attacking even healthy cells and damaging tissues. A KAIST research team has now identified the key mechanism that regulates this excessive activation of killer T cells, offering new insights into controlling immune overreactions and developing therapies for immune-related diseases.
KAIST (President Kwang Hyung Lee) announced on November 5 that a research team led by Professors Eui-Cheol Shin and Su-Hyung Park from the Graduate School of Medical Science and Engineering, in collaboration with Professor Hyuk Soo Eun from Chungnam National University College of Medicine, has uncovered the molecular basis of nonspecific activation in killer T cells and proposed a new therapeutic strategy to control it.
Killer T cells (CD8⁺ T cells) selectively eliminate infected cells to prevent viral spread. However, when excessively activated, they can attack uninfected cells, causing inflammation and tissue damage. Such overactive immune responses can lead to severe viral infections and autoimmune diseases.
In 2018, Professor Shin’s team was the first in the world to discover that killer T cells can be nonspecifically activated by cytokines and randomly attack host cells—a phenomenon they termed “bystander activation of T cells”. The current study builds on that discovery by revealing the molecular mechanism driving this abnormal process.
The team focused on a cytokine called interleukin-15 (IL-15). Experiments showed that IL-15 can abnormally excite killer T cells by a bystander activation mechanism, causing them to attack uninfected host cells. However, when there is a concurrent antigen-specific stimulation, IL-15-induced bystander activation is suppressed.
The researchers further identified that this suppression occurs through an intracellular signaling process. When the concentration of calcium ions (Ca²⁺) changes, a protein called calcineurin activates, which in turn triggers a regulatory protein known as NFAT, suppressing IL-15-induced bystander activation of killer T cells. In other words, the calcineurin–NFAT pathway activated by antigen stimulation acts as a brake on overactivation by a bystander mechanism.
The team also discovered that some immunosuppressants, which are known to block the calcineurin pathway, may not always suppress immune responses—in certain contexts, they can instead promote IL-15-induced bystander activation of killer T cells. This finding underscores that not all immunosuppressants work the same way and that treatments must be carefully tailored to each patient’s immune response.
Through gene expression analysis, the researchers identified a gene set that increase only in abnormally activated killer T cells induced by IL-15 as markers. They further confirmed that these same markers were elevated in bystander killer T cells from patients with acute hepatitis A, suggesting that the markers could be used for disease diagnosis.
<In a normal immune response, killer T cells are activated by antigen stimulation and selectively eliminate only virus-infected cells, thereby controlling viral replication and promoting the patient’s rapid recovery. However, when killer T cells are nonspecifically overactivated by interleukin-15, they may randomly attack normal cells as well, causing excessive tissue damage and leading to severe disease. Future research may identify diseases in which such nonspecific hyperimmune responses occur, making it possible to develop new drugs to control them>
This study provides crucial clues for understanding the pathogenesis of various immune-related diseases, including severe viral infections, chronic inflammatory disorders, autoimmune diseases, and organ transplant rejection. It also paves the way for developing novel immunoregulatory therapies targeting IL-15 signaling.
Professor Eui-Cheol Shin explained that, “this study shows that killer T cells are not merely defenders—they can transform into ‘nonspecific attackers’ depending on the inflammatory environment. By precisely regulating this abnormal activation, we may be able to develop new treatments for intractable immune diseases.”
This research was published in the journal Immunity on October 31, with Dr. Hoyoung Lee and Ph.D. candidate So-Young Kim as co–first authors.
Title: “TCR signaling via NFATc1 constrains IL-15-induced bystander activation of human memory CD8⁺ T cells”, DOI: doi.org/10.1016/j.immuni.2025.10.002
The study was supported by the National Research Foundation of Korea (NRF), the Korea Health Industry Development Institute (KHIDI), and the Institute for Basic Science (IBS).
KAIST Researchers Uncover Critical Security Flaws in Global Mobile Networks
Breakthrough Discovery Reveals How Attackers Can Remotely Manipulate User Data Without Physical Proximity
DAEJEON, South Korea — In an era when recent cyberattacks on major telecommunications providers have highlighted the fragility of mobile security, researchers at the Korea Advanced Institute of Science and Technology have identified a class of previously unknown vulnerabilities that could allow remote attackers to compromise cellular networks serving billions of users worldwide.
The research team, led by Professor Yongdae Kim of KAIST's School of Electrical Engineering, discovered that unauthorized attackers could remotely manipulate internal user information in LTE core networks — the central infrastructure that manages authentication, internet connectivity, and data transmission for mobile devices and IoT equipment.
The findings, presented at the 32nd ACM Conference on Computer and Communications Security in Taipei, Taiwan, earned the team a Distinguished Paper Award, one of only 30 such honors selected from approximately 2,400 submissions to one of the field's most prestigious venues.
A New Class of Vulnerability
The vulnerability class, which the researchers termed "Context Integrity Violation" (CIV), represents a fundamental breach of a basic security principle: unauthenticated messages should not alter internal system states. While previous security research has primarily focused on "downlink" attacks — where networks compromise devices — this study examined the less-scrutinized "uplink" security, where devices can attack core networks.
"The problem stems from gaps in the 3GPP standards," Professor Kim explained, referring to the international body that establishes operational rules for mobile networks. "While the standards prohibit processing messages that fail authentication, they lack clear guidance on handling messages that bypass authentication procedures entirely."
The team developed CITesting, the world's first systematic tool for detecting these vulnerabilities, capable of examining between 2,802 and 4,626 test cases — a vast expansion from the 31 cases covered by the only previous comparable research tool, LTEFuzz.
Widespread Impact Confirmed
Testing four major LTE core network implementations — both open-source and commercial systems — revealed that all contained CIV vulnerabilities. The results showed:
Open5GS: 2,354 detections, 29 unique vulnerabilities
srsRAN: 2,604 detections, 22 unique vulnerabilities
Amarisoft: 672 detections, 16 unique vulnerabilities
Nokia: 2,523 detections, 59 unique vulnerabilities
The research team demonstrated three critical attack scenarios: denial of service by corrupting network information to block reconnection; IMSI exposure by forcing devices to retransmit user identification numbers in plaintext; and location tracking by capturing signals during reconnection attempts.
Unlike traditional attacks requiring fake base stations or signal interference near victims, these attacks work remotely through legitimate base stations, affecting anyone within the same MME (Mobility Management Entity) coverage area as the attacker — potentially spanning entire metropolitan regions.
Industry Response and Future Implications
Following responsible disclosure protocols, the research team notified affected vendors. Amarisoft deployed patches, and Open5GS integrated the team's fixes into its official repository. Nokia, however, stated it would not issue patches, asserting compliance with 3GPP standards and declining to comment on whether telecommunications companies currently use the affected equipment.
"Uplink security has been relatively neglected due to testing difficulties, implementation diversity, and regulatory constraints," Professor Kim noted. "Context integrity violations can pose serious security risks."
The research team, which included KAIST doctoral students Mincheol Son and Kwangmin Kim as co-first authors, along with Beomseok Oh and Professor CheolJun Park of Kyung Hee University, plans to extend their validation to 5G and private 5G environments. The tools could prove particularly critical for industrial and infrastructure networks, where breaches could have consequences ranging from communication disruption to exposure of sensitive military or corporate data.
The research was supported by the Ministry of Science and ICT through the Institute for Information & Communications Technology Planning & Evaluation, as part of a project developing security technologies for 5G private networks.
With mobile networks forming the backbone of modern digital infrastructure, the discovery underscores the ongoing challenge of securing systems designed in an era when such sophisticated attacks were barely conceivable — and the urgent need for updated standards to address them.
Students' Choice for Best UniversityNo. 1, Increase of approximately 2fold in Early Admission Applicants over 3 years
KAIST was selected as the number one 'Best University' by students. According to a recent survey, people in their teens to 50s rated KAIST as the most outstanding university (INUE-Korea Economic Daily University Evaluation). This shows that KAIST's innovative research and creative educational environment are highly regarded by the younger generation. KAIST announced that a total of 6,991 people applied for the 2026 academic year's undergraduate domestic early admission process. This is an increase of 491 people (7.6%) compared to the previous year, with the competition rate rising from 7.98:1 last year to 8.47:1 this year, continuing an upward trend for the fourth consecutive year. Notably, the scale of applications has increased by about 1.9 times compared to the 2023 academic year, showing a significant growth trend. This result aligns with the change in perception revealed in the '2025 INUE-Korea Economic Daily University Evaluation.' In this survey, those in their teens to 50s evaluated KAIST as the top university, but those over 60 years old rated Seoul National University highest, confirming a generational difference in perception. The steady increase in applicants, despite the decrease in the school-age population and the phenomenon of avoiding science and engineering fields, proves that KAIST's educational innovation and global competitiveness are receiving high trust from students. The upward trend in graduate school applicants is also evident. The number has increased by an annual average of 9.5% over the past four years, and foreign applicants have surged by 193%, greatly expanding the interest of outstanding international talents. This shows that KAIST's world-class faculty and cutting-edge research infrastructure are internationally recognized for their competitiveness. The student retention rate has also improved. The number of undergraduate dropouts decreased from 126 in the 2022 academic year to 96 in the 2024 academic year, and voluntary withdrawals to pursue medical or dental fields decreased from 58 to 44 during the same period. This result reverses the expectation that the number of dropouts would increase due to the expansion of medical school quotas. This success is analyzed as the result of KAIST's selection process, which comprehensively evaluates various materials such as the student record, self-introduction letter, and teacher recommendation, rather than just focusing on grades, to reflect not only academic competency but also the 'KAIST DNA' and the motivation for admission. KAIST has also introduced student-centered education systems such as the 'Undecided Major System' and the 'PNR System (Pass or No Record System),' expanding the autonomy of career choice. Through institutional innovation, such as the establishment of the Creative Challenge track and the activation of the Science Gifted Selection System, the university is enabling more outstanding talents to challenge themselves at KAIST. Yong Hyun Kim, KAIST's Dean of Admissions, explained, "As a result of supporting creative talent development and broadening the autonomy of career choice through student-centered systems such as the Undecided Major System and the PNR System which innovates grade notation, the number of applicants continues to increase despite difficult conditions." Kwang Hyung Lee, President of KAIST, stated, "The steady increase in science and engineering talents choosing KAIST is proof that our university's educational and research competitiveness is internationally recognized. The fact that people in their teens to 50s chose KAIST as the 'Best University, No. 1' in a recent survey shows a change in generational values and proves that KAIST is a university that will lead future innovation." He added, "KAIST will continue to nurture the best science and engineering talents that the nation and society need."
KAIST Develops an AI Semiconductor Brain Combining Transformer's Intelligence and Mamba's Efficiency
<(From Left) Ph.D candidate Seongryong Oh, Ph.D candidate Yoonsung Kim, Ph.D candidate Wonung Kim, Ph.D candidate Yubin Lee, M.S candidate Jiyong Jung, Professor Jongse Park, Professor Divya Mahajan, Professor Chang Hyun Park>
As recent Artificial Intelligence (AI) models’ capacity to understand and process long, complex sentences grows, the necessity for new semiconductor technologies that can simultaneously boost computation speed and memory efficiency is increasing. Amidst this, a joint research team featuring KAIST researchers and international collaborators has successfully developed a core AI semiconductor 'brain' technology based on a hybrid Transformer and Mamba structure, which was implemented for the first time in the world in a form capable of direct computation inside the memory, resulting in a four-fold increase in the inference speed of Large Language Models (LLMs) and a 2.2-fold reduction in power consumption.
KAIST (President Kwang Hyung Lee) announced on the 17th of October that the research team led by Professor Jongse Park from KAIST School of Computing, in collaboration with Georgia Institute of Technology in the United States and Uppsala University in Sweden, developed 'PIMBA,' a core technology based on 'AI Memory Semiconductor (PIM, Processing-in-Memory),' which acts as the brain for next-generation AI models.
Currently, LLMs such as ChatGPT, GPT-4, Claude, Gemini, and Llama operate based on the 'Transformer' brain structure, which sees all of the words simultaneously. Consequently, as the AI model grows and the processed sentences become longer, the computational load and memory requirements surge, leading to speed reductions and high energy consumption as major issues.
To overcome these problems with Transformer, the recently proposed sequential memory-based 'Mamba' structure introduced a method for processing information over time, increasing efficiency. However, memory bottlenecks and power consumption limits still remained.
Professor Park Jongse's research team designed 'PIMBA,' a new semiconductor structure that directly performs computations inside the memory in order to maximize the performance of the 'Transformer–Mamba Hybrid Model,' which combines the advantages of both Transformer and Mamba.
While existing GPU-based systems move data out of the memory to perform computations, PIMBA performs calculations directly within the storage device without moving the data. This minimizes data movement time and significantly reduces power consumption.
<Analysis of Post-Transformer Models and Proposal of a Problem-Solving Acceleration System>
As a result, PIMBA showed up to a 4.1-fold improvement in processing performance and an average 2.2-fold decrease in energy consumption compared to existing GPU systems.
The research outcome is scheduled to be presented on October 20th at the '58th International Symposium on Microarchitecture (MICRO 2025),' a globally renowned computer architecture conference that will be held in Seoul. It was previously recognized for its excellence by winning the Gold Prize at the '31st Samsung Humantech Paper Award.' ※Paper Title: Pimba: A Processing-in-Memory Acceleration for Post-Transformer Large Language Model Serving, DOI: 10.1145/3725843.3756121
This research was supported by the Institute for Information & Communications Technology Planning & Evaluation (IITP), the AI Semiconductor Graduate School Support Project, and the ICT R&D Program of the Ministry of Science and ICT and the IITP, with assistance from the Electronics and Telecommunications Research Institute (ETRI). The EDA tools were supported by IDEC (the IC Design Education Center).