Professor Sang-Eun Cho’s Research Team Develops Next-Generation Circularly Polarized Luminescent Semiconductor Materials

-Achieved stable circularly polarized luminescence (CPL) from achiral perovskite nanocrystals-Presents potential for future optoelectronic and semiconductor-integrated devices-Published in Advanced Functional Materials (Impact Factor 19.1) ▲ From left: Sang-Eun Cho, Department of System Semiconductor; Atanu Jana; and Devlinadas, PhD candidateDongguk University (President Jae-Woong Yoon) announced that Professor Sang-Eun Cho from the School of System Semiconductor Engineering and his research team have successfully developed a stable and tunable circularly polarized luminescence (CPL) material that emits across the full visible spectrum—based on achiral perovskite nanocrystals (PNCs).The study, titled “Ultrastable Perovskite Encased in a Helical Cage for Tunable Full-Color Mirror-Image Circularly Polarized Luminescence,” was recently published online in Advanced Functional Materials (Impact Factor 19.1), a prestigious journal in the fields of materials science and nanotechnology. The article is scheduled to appear in the November 2025 print issue.The research team developed a novel polymer-capped PNC composite, integrating a surface adsorption and ion exchange strategy using two-dimensional ZrH₂P₂O₈ nanosheets. This approach simultaneously addressed two major limitations of existing CPL materials—low photoluminescence efficiency and poor stability. As a result, the photoluminescence quantum yield (PLQY) of the nanocrystal composite was dramatically improved from 30.9% to 88.57%.Furthermore, by embedding the stabilized PNCs into a chiral polymer matrix, the team successfully demonstrated clear mirror-image CPL signals in both solution and solid states. This achievement represents a rare example of inducing strong CPL behavior from inherently achiral materials, and holds significant promise for applications in next-generation displays, quantum communication, optical memory devices, and bio-imaging technologies.Professor Cho stated, “Our work demonstrates that even achiral perovskite nanocrystals can exhibit highly stable and efficient CPL characteristics. This material offers a strong foundation for advancing future optoelectronic and semiconductor-integrated technologies where both stability and emission efficiency are critical.”

Professor Jeongin Son’s Joint Research Team Develops Key Technology for Next-Generation Anode-Free Solid-State Batteries

-Innovative Au–F interfacial layer resolves key challenge in anode-free solid-state batteries-Successfully suppresses lithium dendrite growth — a major breakthrough for commercialization-Featured as the cover article in Advanced Energy Materials (Impact Factor 26.0) ▲ From left: Jung-In Son, Dongguk University; Seung-Hyun Hong, Kookmin University; and Yeo-Jeong Jang, Dongguk University Dongguk University (President Jae-Woong Yoon) announced that Professor Jeongin Son from the Department of Physics, in collaboration with Professor Seunghyun Hong from the Department of Materials Science and Engineering at Kookmin University, has developed a thermodynamically stable gold-fluorine (Au–F) interfacial layer that addresses one of the most critical challenges in anode-free solid-state lithium metal batteries—non-uniform lithium deposition and dendritic growth.The research, titled "Thermodynamically-Favorable Tailored Au–F Interface for Uniform Lithium Deposition in Anode-Free Solid-State Batteries," was published in the September 2025 issue of Advanced Energy Materials (Impact Factor: 26.0, JCR top 3.5%), a leading journal in the fields of physics, materials science, and nanotechnology. Recognizing the significance of the findings, the article was selected as the cover paper for the issue.Anode-free solid-state lithium metal batteries are gaining attention as next-generation high-energy-density batteries, as they eliminate conventional anode materials and use only a copper current collector. However, a major limitation has been the lattice mismatch between lithium and copper, which leads to non-uniform initial lithium deposition, triggering the formation of dendrites that degrade efficiency and cause lithium loss. In this context, developing interfacial engineering techniques to guide uniform lithium growth has become essential.The joint research team successfully overcame this challenge by introducing a gold-fluorine interfacial layer, which promotes thermodynamically favorable lithium nucleation and deposition.Professor Son stated, “In anode-free solid-state batteries, the uniform deposition of lithium plays a critical role in improving both interfacial stability and battery performance. The Au–F interfacial layer we developed effectively reduces the energy barrier for lithium nucleation and enables precise control of ion diffusion, fundamentally suppressing dendrite formation.”He further added, “This approach induces a layered and uniform lithium deposition, resulting in high capacity retention and excellent Coulombic efficiency. Ultimately, this innovation is expected to significantly accelerate the commercialization of next-generation high-performance anode-free solid-state batteries.”This research was supported by the Nano and Material Technology Development Program and the Mid-Career Researcher Program of the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (MSIT).

Professor Youngsung Kim’s Team Develops High-Performance DC Energy Harvesting Device for Wearable Applications

-Joint research with University of Calgary, Canada-Developed a novel DC-output energy harvesting device based on nanoporous carbon materials-Achieved 5.7 times higher performance than conventional devices-Published in the internationally renowned journal Chemical Engineering Journal (Impact Factor 13.4) ▲ Yeong-Seong Kim, Department of Mechanical, Robotics, and Energy Engineering Dongguk University (President Jae-Woong Yoon) announced that Professor Youngsung Kim from the Department of Mechanical, Robotics and Energy Engineering, in collaboration with a research team from the University of Calgary (Canada), has developed a next-generation energy harvesting and sensing device based on biomechanical motion.The international research team focused on harvesting biomechanical energy and developed a compact device that can be embedded into the insole of a shoe. The team explained that the device “achieved simplified design and miniaturization by employing a Kapton-based mechanical rectifier, while maximizing the surface area, porosity, and charge storage characteristics of nanoporous carbon materials.”▲ graphical abstractThe newly developed high-efficiency carbon-based device demonstrated an approximately 5.7-fold performance improvement over existing technologies and successfully passed durability testing over more than 40,000 cycles. Unlike conventional alternating current (AC)-based systems, this device generates direct current (DC) power without the need for complex rectifier circuits, making it highly applicable to wearable electronics, IoT sensor nodes, sports and medical devices, and portable electronics.Professor Kim stated, “We have developed a material and device structure along with a mechanical operation mechanism that ensures durability even when embedded in a shoe insole. This research overcomes the limitations of conventional materials and proposes optimized strategies for device design and fabrication.” He added, “While the device is currently based on biomechanical motion, we expect it could also be applied to energy harvesting systems for robotic platforms that involve repetitive mechanical movements.”The study, titled “Bimetallic nanoporous carbon-based direct-current triboelectric nanogenerators for biomechanical energy harvesting and sensing,” was published in the September 2025 issue of the Chemical Engineering Journal, a globally respected journal (Impact Factor: 13.4, top 3.1% in JCR).This work was supported by the Ministry of Science and ICT (MSIT) through the NRF Leading Research Center Program, and by the Ministry of Trade, Industry and Energy (MOTIE) through KIAT’s Industrial Innovation Talent Growth Program.

Dongguk University Scientists Uncover Novel Battery Design for Industrial Energy Storage

Researchers developed a graphene coating that supercharges zinc-ion batteries for grid useZinc-ion batteries are promising for energy storage, but their traditional current collectors suffer from scalability issues, restricting industrial applications. In a recent study, researchers from Dongguk University have designed a novel alternative current collector in the form of graphene-coated stainless-steel foil. Consequently, they achieve batteries with high electrochemical performance and superior cycling stability, potentially paving the way for industrial-scale systems.<Towards high-performance industrial-scale zinc-ion battery>The present century has witnessed a proactive shift towards more sustainable forms of energy, including renewable resources such as solar power, wind, nuclear energy, and geothermal energy. These technologies naturally require robust energy storage systems for future usage. In recent years, lithium-ion batteries have emerged as dominant energy storage systems. However, they are known to suffer from critical safety issues.In this regard, zinc-ion batteries based on water-based electrolytes offer a promising solution. They are inherently safe, environmentally friendly, as well as economically viable. These batteries also mitigate fire risks and thermal runaway issues associated with their lithium-based counterparts, which makes them lucrative for grid-scale energy storage. Furthermore, zinc has high capacity, low cost, ample abundance, and low toxicity. Unfortunately, current collectors utilized in zinc-ion batteries, such as graphite foil, are difficult to scale up and suffer from relatively poor mechanical properties, limiting their industrial use.In a new breakthrough, a team of researchers from Republic of Korea, led by Associate Professor Geon-Hyoung An at the Department of Energy and Materials Engineering at Dongguk University, has proposed graphene-coated stainless steel foil as a novel alternative current collector. Their findings were published in the journal Advanced Energy Materials on April 02, 2025.According to Prof. An, “The core innovation of the present study is the use of graphene-coated stainless-steel foil, or G@SSF-400, as a current collector for zinc-ion batteries. Unlike conventional collectors, our material can be produced through a simple graphene coating and heat treatment for surface oxide removal. This enables both industrial scalability and high electrochemical performance.”This innovation overcomes the common challenges of corrosion and poor conductivity seen in water-based systems and operates stably even under high-mass loading conditions, which is essential for practical use. Notably, the battery exhibited high specific capacities exceeding 1 mAh cm-2, as well as retained 88.7% of its capacity after 1,500 cycles, a strong indicator of long-term durability. Furthermore, because this technology supports roll-to-roll manufacturing, it opens the door to large-scale production, bringing zinc-ion batteries closer to commercialization in the energy storage sector.“This technology is highly suitable for grid-scale energy storage systems, especially in the context of renewable energy integration. By enabling the use of water-based zinc-ion batteries, our approach provides a non-flammable, cost-effective, and environmentally friendly alternative to traditional lithium-ion systems,” remarks Prof. An.Consequently, this research could contribute significantly to the global shift toward clean and resilient energy systems. It addresses key barriers in energy storage, including cost, scalability, and safety, especially in underserved markets. By reducing dependence on expensive or hazardous materials, such as those used in lithium-ion batteries, this technology supports the development of a more sustainable and circular battery economy. In practical terms, it could lead to wider access to affordable energy storage. In the long run, this could play a role in mitigating climate change, enhancing energy equity, and accelerating the global energy transition.In summary, the proposed next-generation technology furthers large-scale high-performance zinc-ion batteries as a safe and scalable energy storage solution.ReferenceTitle of original paper: Industrial Scalability of Zinc-Ion Batteries: Enhanced Electrochemical Performance with High Mass Loading Electrodes on Graphene-Coated Metal Current CollectorsJournal: Advanced Energy MaterialsDOI: https://doi.org/10.1002/aenm.202500261About Dongguk UniversityDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About Professor Geon-Hyoung from Dongguk UniversityProf. Geon-Hyoung An is an Associate Professor in the Department of Energy and Materials Engineering at Dongguk University. His research focuses on electrochemical energy storage systems, aiming to develop advanced materials and scalable battery technologies for safe, sustainable applications. He earned his Ph.D. from Seoul National University of Science and Technology in 2018 and conducted postdoctoral research at the University of Oxford. From 2019 to 2025, he served as an Associate Professor in the Department of Energy Engineering at Gyeongsang National University.

Dongguk University Researchers Advance Lithium-Ion Battery Technology with Hybrid Anode Material

Innovative nanoscale engineering enhances energy storage and cycling stability, addressing the growing demand for efficient energy solutionsResearchers from Dongguk University have achieved a significant breakthrough in lithium-ion battery technology by developing a novel hybrid anode material. This innovative study introduces a hierarchical heterostructure composite that optimizes material interfaces at the nanoscale, resulting in remarkable enhancements in energy storage capacity and long-term cycling stability. This engineered structure integrates graphene oxide's superior conductivity with the energy storage capabilities of nickel-iron compounds for future electronics and energy solutions.<Revealing Hierarchical Heterostructures for Enhanced Energy Storage>Lithium-ion batteries are the dominant energy storage technology powering everything from portable electronics to electric vehicles and renewable energy systems. However, the demand for higher energy density, faster charging, and longer lifespans necessitates continuous innovation.Researchers, led by Professor Jae-Min Oh of Dongguk University, in collaboration with Seung-Min Paek of Kyungpook National University, are addressing these challenges by engineering materials at the nanoscale. Their work, available online on January 28, 2025, and published in volume 506 of the Chemical Engineering Journal on January 15, 2025, focuses on a novel hybrid material designed to maximize the synergistic effects of its components. This innovative composite is a hierarchical heterostructure that combines reduced graphene oxide (rGO) with nickel-iron layered double hydroxides (NiFe-LDH). This unique composite leverages the properties of its components: rGO provides a conductive network for electron transport, and the nickel-iron-oxide components enable fast charge storage through a pseudocapacitive mechanism. The key to this innovative design is the abundance of grain boundaries, which facilitate efficient charge storage.To achieve the final composite, the researchers employed a layer-by-layer self-assembly technique using polystyrene (PS) bead templates. First, the PS beads were coated with GO and NiFe-LDH precursors. The templates were then removed, leaving behind a hollow sphere architecture. Following this, a controlled thermal treatment induced a phase transformation in NiFe-LDH, leading to the formation of nanocrystalline nickel-iron oxide (NiFe₂O₄) and amorphous nickel oxide (a-NiO), while simultaneously reducing GO to rGO. This synthesis resulted in a well-integrated hybrid composite (rGO/NiFe₂O₄/a-NiO), with enhanced conductivity making it an efficient anode material for lithium-ion batteries. This hollow structure prevents direct contact between the a-NiO/NiFe₂O₄ nanoparticles and the electrolyte, improving stability.Advanced characterization techniques, such as X-ray diffraction and transmission electron microscopy, were then used to confirm the composite's formation. Electrochemical tests revealed the material's exceptional performance as a lithium-ion battery anode. The anode demonstrated a high specific capacity of 1687.6 mA h g−1 at a current density of 100 mA g−1 after 580 cycles, surpassing conventional materials and highlighting its excellent cycling stability. Furthermore, the material exhibited good rate performance, maintaining high capacity even at significantly increased charge/discharge rates.Professor Seung-Min Paek emphasized the collaborative nature of the research, "This breakthrough was made possible through close cooperation between experts in diverse materials. By combining our strengths, we were able to design and optimize this hybrid system more effectively. "Professor Jae-Min Oh added, "We anticipate that, in the near future, energy storage materials will move beyond simply improving individual components. Instead, they will involve multiple interacting materials that create synergy, resulting in more efficient and reliable energy storage devices. This research offers a pathway to smaller, lighter, and more efficient energy storage for next-generation electronic devices."This development targets significantly improved batteries (longer life, faster charge, lighter) within 5-10 years, benefiting both device users and sustainable energy initiatives.ReferenceTitle of original paper: Phase change-induced heterointerface engineering of hollow sphere structured graphene oxide/layered double hydroxide composites for superior pseudocapacitive energy storage in lithium-ion batteriesJournal: Chemical Engineering JournalDOI: 10.1016/j.cej.2025.159671About the instituteDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About Professor Jae-Min OhDr. Jae-Min Oh earned his PhD from Seoul National University and completed postdoctoral research in France and Korea. He has held professorships at Yonsei University and currently serves as a professor at Dongguk University. His research group focuses on the synthesis, characterization, and application of layered inorganic materials, particularly layered double hydroxides (LDHs) and two-dimensional (2D) nanomaterials, including MXenes and graphene oxide. His work spans diverse areas, including: advanced energy storage and conversion devices (lithium-ion batteries, sodium-ion batteries, supercapacitors, and photovoltaics), biomedical applications (drug delivery, biocompatible materials, and diagnostics), and environmental remediation (pollutant removal and gas adsorption). He also investigates interfacial engineering to optimize material properties for these applications.

Dongguk University Researchers Develop Wavelet-Based Adversarial Training: A Breakthrough Defense System for Medical Digital Twins

This method enables medical digital twins to achieve 98% accuracy in breast cancer prediction, even under adversarial attacksMedical digital twins are virtual models of the human body that can help predict diseases with high accuracy. However, they are vulnerable to cyberattacks that can manipulate data and lead to incorrect diagnoses. To address this, researchers from Dongguk University developed the Wavelet-Based Adversarial Training (WBAD) defense system. Tested on a breast cancer diagnostic model, WBAD restored accuracy to 98% against attacks, ensuring safer and more reliable medical digital twins for healthcare applications.<Wavelet-Based Adversarial Training (WBAD) defense mechanism to secure medical digital twins against cyberattacks>A digital twin is an exact virtual copy of a real-world system. Built using real-time data, they provide a platform to test, simulate, and optimize the performance of their physical counterpart. In healthcare, medical digital twins can create virtual models of biological systems to predict diseases or test medical treatments. However, medical digital twins are susceptible to adversarial attacks, where small, intentional modifications to input data can mislead the system into making incorrect predictions, such as false cancer diagnoses, posing significant risks to the safety of patients.To counter these threats, a research team from Dongguk University, Republic of Korea, and Oregon State University, USA, led by Professor Insoo Sohn, has proposed a novel defense algorithm: Wavelet-Based Adversarial Training (WBAD). Their approach, which aims to protect medical digital twins against cyberattacks, was made available online on October 11, 2024, and is published in volume 115 of the March 2025 issue of the journal Information Fusion.“We present the first study within Digital Twin Security to propose a secure medical digital twin system, which features a novel two-stage defense mechanism against cyberattacks. This mechanism is based on wavelet denoising and adversarial training,” says Professor Insoo Sohn, from Dongguk University, the corresponding author of the study.The researchers tested their defense system on a digital twin designed to diagnose breast cancer using thermography images. Thermography detects temperature variations in the body, with tumors often appearing as hotter regions due to increased blood flow and metabolic activity. Their model processes these images using Discrete Wavelet Transform, which extracts essential features to create Initial Feature Point Images. These features are then fed into a machine learning classifier trained on a dataset of 1,837 breast images (both healthy and cancerous), to distinguish between normal and tumorous tissue.Initially, the model achieved 92% accuracy in predicting breast cancer. However, when subjected to three types of adversarial attacks—Fast Gradient Sign Method, Projected Gradient Descent, and Carlini & Wagner attacks—its accuracy dropped drastically to just 5%, exposing its vulnerability to adversarial manipulations. To counter these threats, the researchers introduced a two-layer defense mechanism. The first layer, wavelet denoising, is applied during the image preprocessing stage. Adversarial attacks typically introduce high-frequency noise into input data to mislead the model. Wavelet denoising applies soft thresholding to remove this noise while preserving the low-frequency features of the image.To further improve the model's resilience, the researchers added an adversarial training step, which trains the machine learning model to recognize and resist adversarial inputs. This two-step defense strategy proved highly effective, with the model achieving 98% accuracy against FGSM attacks, 93% against PGD attacks, and 90% against C&W attacks.“Our results demonstrate a transformative approach to medical digital twin security, providing a comprehensive and effective defense against cyberattacks and leading to enhanced system functionality and reliability,” says Prof. Sohn.ReferenceTitle of original paper: Adversarial robust image processing in medical digital twinJournal: Information FusionDOI: 10.1016/j.inffus.2024.102728About the instituteDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About the authorInsoo Sohn is a Professor in the Division of Electronics and Electrical Engineering at Dongguk University. He worked as a Senior Network Engineer at Ericsson, Dallas, in 1998. From January 1999 to February 2004, he was a Senior Researcher at ETRI, Daejeon. In March 2004, he became an Assistant Professor in the Communications Engineering Department at Myongji University. He received a B.S. degree from Rensselaer Polytechnic Institute (1994), an M.S. degree from New Jersey Institute of Technology (1995), and a Ph.D. degree from Southern Methodist University (1998). His group researches cybersecurity, machine learning, digital twin systems, and semantic communications.

Dongguk University Researchers Create Clove Essential Oil-Based Pickering Emulsions

Researchers demonstrate how modifying the properties of clove essential oil can improve emulsifying efficiency and enhance antibacterial effectsClove essential oil is a promising antibacterial substance. In a new study, researchers from Dongguk University explore a sustainable way to create carbon quantum dots (CQDs) from clove residue left after extracting essential oil. These CQDs were tested for their ability to form Pickering emulsions, which are more stable and have enhanced antibacterial properties compared to traditional emulsions using Polysorbate 80. Thus, the proposed emulsions are promising for food and cosmetic applications.<A Sustainable Alternative to Synthetic Emulsifiers Using Clove-Based Nanotechnology>Foodborne diseases pose a significant challenge to achieving the United Nations Sustainable Development Goal 3 of Good Health and Well-Being. Such ailments typically occur due to bacterial contamination during food production, processing, transportation, and storage and can even prove fatal. Therefore, it is imperative to prevent contamination due to microbes at all stages.In this regard, the food industry currently utilizes chemicals such as benzoate and nitrate. Unfortunately, these preservatives are not deemed as safe and effective natural antibacterial agents. Scientists have recently proposed essential oils, volatile substances produced through the secondary metabolism of plants, as promising alternatives.In a breakthrough, a team of researchers led by Jun-Won Kang, an Assistant Professor in the Department of Food Science and Biotechnology at Dongguk University, has come up with a novel clove essential oil-based Pickering emulsion formulation with enhanced antibacterial properties. Their findings were made available online on 3 December 2024 and published in Volume 503 of the Chemical Engineering Journal on 1 January 2025.According to Dr. Kang, “Clove essential oil is known to exhibit excellent antibacterial properties. However, its application has been limited by low water solubility. To overcome this, we decided to explore oil-based Pickering emulsions.”In this study, the researchers developed a sustainable Pickering emulsion using carbon quantum dots (CQDs), promising solid particles for food applications, derived from clove essential oil residue. Specifically, they synthesized four kinds of CQDs using ultrapure distilled water and ethanol, finding that CQDs with 40% ethanol demonstrated the highest emulsifying efficacy.CQDs increase the surface roughness of the emulsion, enhancing bacterial adhesion and leading to stronger antibacterial activity compared to conventional emulsions. The present approach not only enhances the antibacterial efficiency of emulsions but also offers a green and eco-friendly alternative to traditional chemical surfactants such as Polysorbate 80. It showcases the upcycling of essential oil extraction byproducts into valuable emulsifying agent nanomaterials, contributing to sustainable material development and waste valorization.This work is expected to find several interesting applications across numerous fields. The developed Pickering emulsion can be used in food preservation and packaging to enhance shelf life by naturally preventing bacterial contamination. Additionally, since essential oils are already widely used in skincare products, the proposed emulsion could be used in natural cosmetics and topical antimicrobial formulations.Moreover, the antimicrobial properties of emulsion suggest potential applications in wound dressings, antiseptic formulations, or drug delivery systems. The formulation could also be applied to biopesticides or plant protection products that require stable emulsions with antimicrobial action.“To summarize, the novelties of our clove essential oil-based technology include reduction of chemical surfactants, health benefits, sustainability, waste reduction, circular economy promotion, advanced antimicrobial features, medical applications, and potential for widespread industrial adoption,” concludes Dr. Kang.Here’s hoping that this research soon leads to new regulatory standards favouring eco-friendly, bio-based, and non-toxic emulsifiers over synthetic ones, shaping the landscape of multiple industries!ReferenceTitle of original paper: Synthesis and characterization of clove residue-derived carbon quantumdots: Application in Pickering emulsion with enhanced antibacterial propertiesJournal: Chemical Engineering JournalDOI: https://doi.org/10.1016/j.cej.2024.158247About the instituteDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About the authorProfessor Jun-Won Kang, an Assistant Professor in the Department of Food Science and Biotechnology at Dongguk University, applies cutting-edge nanotechnology to control foodborne pathogens and antibiotic-resistance genes, contributing to food safety and public health. Expanding his research scope, he recently explored probiotic engineering to develop functional and therapeutic food microbiomes. His work spans microbial safety and engineering beneficial microorganisms, aiming to pioneer next-generation probiotics that address global health challenges while ensuring food sustainability. Through interdisciplinary approaches, he advances innovations in food microbiology.

Dongguk University Develops Gel-Based Stretchable Triboelectric Nanogenerators for Wearable Technology

This nanogenerator overcomes limitations of traditional electrode materials, offering flexibility and long-lasting performance for wearable applicationsImagine a future where your clothes power your devices and recognize you with a simple tap. Researchers at Dongguk University have developed a gel polymer-based triboelectric nanogenerator that generates electrical signals from body movement to power electronics like LEDs and functions as a self-powered touch panel for user identification. The device can stretch up to 375% of its original size and withstand rigorous mechanical deformations, making it suitable for wearable applications.<An in-situ curing strategy to develop a stretchable, semi-transparent, and durable GPE-TENG>From smartwatches, and fitness trackers to medical sensors that can be worn on the body, wearables are transforming the way we interact with technology. As their popularity grows, triboelectric nanogenerators (TENGs) that convert mechanical energy such as body movement to electrical energy offer a solution to power these devices without relying on batteries.Most TENGs used in wearable applications incorporate a triboelectric material attached to an electrode that conducts current. However, one of the challenges has been finding flexible electrode materials that can move seamlessly with the human body.To address these challenges, a research team led by Professor Jung Inn Sohn from Dongguk University-Seoul in the Republic of Korea developed a gel polymer electrode-based triboelectric nanogenerator (GPE-TENG). This device is stretchable, semi-transparent, and durable, making it suitable for wearable sensor applications. This paper was made available online on 11 Oct 2024 and was published in Volume 499 of the Chemical Engineering Journal on 1 Nov 2024.“We report an in-situ curing strategy to develop a stretchable, semi-transparent, and durable GPE-TENG through enhanced interfacial bonding between the ionic polymer gel and ecoflex layers,” explains Prof. Sohn.To fabricate the device, the researchers poured a gel mixture of polyethylene oxide (PEO) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) into an ecoflex mold. The gel is spread evenly and then covered with another ecoflex layer. A copper wire is attached to the gel for electrical connection, and the entire assembly is cured at 70°C for 12 hours, allowing the gel to bond strongly with the ecoflex layers.The result is a durable, flexible, and semi-transparent device that generates electrical signals when tapped or stretched, delivering a peak power of 0.36 W/m² at a load of 15 MΩ. In tests, the device stretched up to 375% of its original size without damage and could withstand two months of bending, twisting, folding, and stretching without any signs of delamination or loss of electrical performance.As wearable technology becomes a bigger part of our daily lives, the proposed GPE-TENG could enable wearable devices that track joint activity for rehabilitation purposes or act as a biometric system in clothing, allowing users to unlock smart doors or lockers. “This work could revolutionize wearable technology by developing sustainable and flexible electronic devices with promising applications in human healthcare, rehabilitation, security systems, and secure biometric authentication systems,” says Prof. Sohn.ReferenceTitle of original paper: In-situ cured gel polymer/ecoflex hierarchical structure-based stretchable and robust TENG for intelligent touch perception and biometric recognitionJournal: Chemical Engineering JournalDOI: 10.1016/j.cej.2024.156650About the instituteDongguk University, founded in 1906 by the Jogye Order of Korean Buddhism, is a premier Buddhist institution of higher learning. Originally established as Myeongjin School, it is rooted in Buddhist principles, Korean tradition, and historical significance. With a legacy of empowering approximately 350,000 professionals instrumental in Korea's modernization and democratization, the university continues to cultivate future leaders who shape the world while advancing Korean Buddhism, guided by its motto: "The revival of Buddhism fuels Dongguk's growth, and vice versa."About the authorDr. Jung Inn Sohn is currently a Professor in the Division of Physics and Semiconductor Science at Dongguk University, Korea. His research group focuses on developing new low-dimensional materials and exploring their fundamental physical properties and new functions for potential applications in energy and optoelectronics. He was formerly a faculty member at the University of Oxford and a senior researcher at Samsung Advanced Institute of Technology and the University of Cambridge. His research is described in more than 175 SCI articles in top journals including Nature, Nature Communications, Energy & Environ. Sci., as well as 21 cover picture articles and 4 review articles. He has an h-index of 47 and 30 patents to his name.

Self-Compliant Memristive Devices: A Breakthrough in Neuromorphic Computing

Researchers have developed a new memristive device capable of self-compliance, multilevel operation, and a crossbar array for forming neural networks.Neuromorphic or brain-like computing systems offer several advantages for artificial intelligence applications. Resistive random-access memory (RRAM), a type of emerging semiconductor technology, exhibits potential for neuromorphic computing applications. However, conventional designs suffer from overshoot currents, leading to reliability issues and requiring external current compliance settings. Now, researchers have developed a new memristive device that achieves self-compliance, enabling crossbar array and multilevel operation, paving the way toward high-performance neuromorphic computing.<Researchers from Dongguk University propose a memristor device and crossbar array>In the recent years, artificial intelligence (AI) and Internet of Things have progressed rapidly, driving advancements in areas like speech recognition, image classification in autonomous vehicles, and large language models like ChatGPT. A key element in AI is deep learning, which requires parallel processing of large amounts of data—an area where traditional computers still struggle with efficiency. Neuromorphic or brain-like computing systems, consisting of artificial neurons and synapses, offer low power consumption and efficient data processing.One of the most promising semiconductor technologies for neuromorphic computing is the resistive random-access memory (RRAM), a type of memristive device. Memristive devices have the unique ability to “remember” past electrical states. In RRAM, this memory effect arises from the formation and dissolution of a conductive filament (CF) in the insulator layer of its metal-insulator-metal structure. Metal oxide insulators play an essential role in this process. However, while titanium-oxide-based RRAMs offer several advantages, they suffer from device-to-device variations, caused by overshoot currents during CF formation. This can lead to breakdowns or unintended memory erasure. Current methods to mitigate overshoot currents require the addition of transistors or external current compliance (CC) settings, increasing complexity.In a breakthrough now, a research team from South Korea, led by Professor Sungjun Kim from the Division of Electronics and Electrical Engineering at Dongguk University, developed a self-compliance (SC) memristor device that overcomes these issues. Elaborating further, Prof. Kim says, “In this study, we achieved SC on a high-density two-terminal memristor and implemented vector-matrix multiplication (VMM), the core of AI semiconductor computation, on a 32 x 32 memristor array.” Their study was made available online on August 21, 2024, and published in Volume 18, Issue 36 of ACS Nano on September 10, 2024.The innovative memristor device has an aluminum oxide/titanium-oxide (AlOx/TiOy) layer on top of the insulator layer. This layer acts as an internal resistor, preventing overshoot currents by controlling the thickness of the CF formed during switching, which achieves SC. The researchers fine-tuned the TiOy layer to 10 nanometers, improving the device's performance.Through a series of experiments, the researchers demonstrated the device’s consistent switching characteristics without external CC and reliable multilevel operation with low power consumption. They also studied the device’s long-term potentiation (LTP) and long-term depression (LTD) characteristics, which represent the strength of synaptic connections between neurons in neuromorphic computing systems.Using these characteristics, they simulated neural networks based on the device to classify images from the well-known MNIST database. Results revealed an online learning accuracy of 92.36%. Furthermore, offline learning neural networks that leveraged the device’s SC multilevel mode achieved an accuracy of 96.89%.Ultimately, the researchers built a neural network using a 32 x 32 crossbar array of their memristors to demonstrate spiking neural network (SNN)-based VMM operations. SNNs, which mimic the computation processes of the brain, are known for their low power consumption. The crossbar array-based neural network achieved a 94.6% classification accuracy on the MNIST dataset, with only a 1.2% accuracy drop compared to simulation results, which shows its exceptional capabilities.“Memristor arrays will be pivotal in next-generation computing architectures due to their speed, efficiency, and scalability,“ remarks Prof. Kim. “Beyond neuromorphic computing, they have a wide range of potential applications, including non-volatile memory, IoT, machine learning, and cryptography. Furthermore, neural processing units, specialized for AI operations, require memory chips tailored for VMM operations such as the high yield memristor array developed in this study,” he adds.In summary, this innovative device opens avenues for the development of high-performance, energy-efficient neuromorphic computing systems, unlocking advanced new AI applications.ReferenceTitle of original paper: Memristive Architectures Exploiting Self-Compliance Multilevel Implementation on 1 kb Crossbar Arrays for Online and Offline Learning Neuromorphic ApplicationsJournal: ACS NanoDOI: 10.1021/acsnano.4c06942Additional information for EurekAlertLatest Article Publishing Date: September 10, 2024Method of Research: Experimental StudySubject of Research: Not applicableCOI Statement: The authors declare no competing financial interest.About the instituteDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About the authorSungjun Kim is a Professor at Dongguk University, Seoul, Republic of Korea. Professor Kim received his Ph.D. in Electrical Engineering from Seoul National University, Seoul, Republic of Korea, in 2017. From 2017 to 2018, he was a Senior Engineer at Samsung Electronics Company Ltd., Republic of Korea. He joined Chungbuk National University, Republic of Korea, as an Assistant Professor in 2018. His research topics mainly include memristors, ferroelectric memories, other emerging memories, and neuromorphic semiconductors. He has published more than 280 publications in peer-reviewed journals with an h-index of 33 (Scopus, August 2024).

The Changing Landscape of Selecting Restaurants

Scientists at Dongguk University explore the attributes influencing consumers' choice between in-person dining and online food delivery. It investigates the interplay of online and offline platforms and how they evolve with time. The study reveals that while taste remains important, attributes unique to each platform significantly impact satisfaction and future behavior. Understanding these dynamics can help businesses enhance the dining experience and drive satisfaction.<Understanding the attributes that affect the relationship between restaurants and FDA platforms’ satisfaction–behavioral intention linkage>The pandemic brought a significant change in consumer behavior, particularly in the food industry, with more people opting to order food from restaurants through their online delivery services. While visiting restaurants (offline platform) may have been a common practice earlier, the safety and convenience offered by food delivery applications (FDA) (online platform) have made them an attractive option for many consumers during the pandemic.Online and offline platforms may offer comparable qualities of food, but each has unique attributes which might influence the customer's choice of dining experience. However, the dynamics of the interaction between the restaurant- and FDA-specific attributes are not known. Therefore, it is important to understand how these distinct attributes interact and evolve, and impact the customer satisfaction–behavioral intention mechanism.To fill this gap, Professor Hong-Youl Ha and Professor Yiyue Zhang from Dongguk University examined the association between satisfaction and behavioral intention (one’s relative strength of intention to perform a behavior) among restaurants and FDAs.“Our study underscores the importance of shifts in attribute weights on the online-to-offline (O2O) business platform,” explains Prof. Ha sharing the importance of their study.For this, the researchers conducted a two-time lag survey from the beginning of January to the end of June 2022 and collected data from participants who had visited restaurants or used FDAs during the COVID-19 pandemic in mainland China. The respondents rated different attributes of each platform on a 5-point Likert scale. The study was published on 1 January 2024 in Volume 170 of the Journal of Business Research.Analyses revealed that the attributes distinct to restaurants and FDAs are dynamic, and their importance keeps evolving with time. The study offered insights for restaurant and mobile application managers regarding the dynamics of attributes and the satisfaction–intention mechanism from a consumer’s perspective.Explaining the long-term applications of the study, Prof. Ha concludes, "If consumers continue to use food delivery apps, it is possible to better understand the reasons and response directions regarding whether satisfaction with a specific brand is the reason they continue to use that or whether they switch to alternatives because the importance of other attributes changes."ReferenceTitle of original paper: The evolution of consumer restaurant selection: Changes in restaurant andfood delivery application attributes over timeJournal: Journal of Business ResearchDOI: 10.1016/j.jbusres.2023.114323*Corresponding author’s email: hyha@dongguk.eduAbout Dongguk UniversityDongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.Website: https://www.dongguk.edu/eng/About the authorHong-Youl Ha is a Professor of Marketing at Dongguk University-Seoul in Korea. He obtained his PhD from Swinburne University of Technology in Australia. His works have been published in academic journals including the Journal of Computer-Mediated Communication, Journal of Business Research, International Journal of Contemporary Hospitality Management, Current Issues in Tourism, International Marketing Review, European Journal of Marketing, Journal of Hospitality and Tourism Management, Journal of Hospitality Marketing & Management, Service Industries Journal, Journal of Services Marketing, Management Decision, Journal of Consumer Marketing, International Journal of Conflict Management, Asia Business and Management, and Internet Research. Finally, he received the Gallup Korea Award in 2017.