Dongguk University’s Professor Ryu Seung-yoon’s Research Team Publishes a Paper in an Internationally Renowned Academic Journal in the Materials, Physics, and Chemistry Field with Professor Cho Shin-haeng’s Research Team of Chonna

Released a progress report on research utilizing medical equipment (linear particle accelerator) to present an indicator for radiation exposure based on the perovskite solar cellPublished in the 「Journal of Physical Chemistry C」, a renowned international academic journal in the materials, physics, and chemistry field <From left, Professor Ryu Seung-yoon, Professor Cho Shin-haeng, Ph. D. Kim Sang-soo, Ph. D. Candidate Lee Chang-min>○ Professor Ryu Seung-yoon’s team at the Department of Physics and Semiconductor of Dongguk University and Professor Cho Shin-haeng’s team at the Department of Radiation Oncology of the Chonnam National University Hwasun Hospital reported the result of the research on the radiation exposure for the application of the perovskite solar cells. This is basic research on its utilization with a dosimeter, which is used in the hospital, and it suggests, along with optical analysis, that the possibility of deducing the dose as the solar cell does not operate normally after a certain threshold in the research.<Overview of the radiation exposure test using a linear particle accelerator​><Journal of Physical Chemistry C 2024, 128, 885−893, Cover Image>○ Although there were attempts to apply the existing Amorphous silicon (a-Si) and copper indium gallium selenide solar cells (CIGS) as chromoradiometer for medical use, the utilization of perovskite solar cells with strong radiation resistance was not examined. Under the circumstances, a radiation exposure test using a linear particle accelerator was performed to verify whether they could be utilized in extreme environments like space.○ This research irradiated perovskite solar cells with a 6 MeV electron beam for the first time to imitate an extreme environment. The dosage of radiation used for treatment at hospitals is approximately 1 fx / 50 Gy, but this research increased the level to an extreme dose (3 kGy – 21 kGy) for verification. It suggested that a flaw (vacancy, antisite, or distortion) occurs inside the perovskite crystal, and the performance of the solar cell declines at a certain level (15 kGy).○ In addition, the research team cross-validated the flaw inside the perovskite crystal through optical analysis and simulation and suggested using perovskite solar cells under extreme environments. However, it indicated that additional research is necessary to maintain the stability of the perovskite solar cells to utilize them under extreme environments, such as in space.○ Professor Ryu Seung-yoon said with expectations, “Recently, the need for converged and joint research is emerging in various areas. Experts from various fields can work together to make technology more cutting-edge. With Professor Cho Shin-haeng’s team, we were able to study medical dosimeters and technologies to apply under extreme environments, such as in space, by sharing knowledge.”○ Ph. D. Kim Sang-soo and Ph. D. Candidate Lee Chang-min said, “The stability of the perovskite solar cells is still not very high, and it is difficult to prepare and analyze the element, but we engaged in the research to lay the foundation for researching the use of solar cells under extreme environments considering the strong radiation resistance of the perovskite compared to existing solar cells,” giving their impression.○ This research was funded by the National Research Foundation of Korea and Dongguk University and published online and featured on the cover of the January 2024 edition of the distinguished international academic journal in the materials, physics, and chemistry fields 「Journal of Physical Chemistry C (IF=4.17)」 under the title <Radiation Tolerance of Organohalide-Based Perovskite Solar Cells under 6 MeV Electron Beam Irradiation>.

Professor Choi Min-jae’s Team at Dongguk University Develops Near-Infrared Photothermal Anticancer Therapy Using Quantum Dots

<From left, Master Yoo Do-heon, Master Jeong Se-hwan, Professor Kim Gyo-beom, and Professor Choi Min-jae>Dongguk University (President Yun Jae-woong) announced on January 22 that the research team of the Department of Chemical Engineering and Biotechnology, comprising Master Yoo Do-heon (First Co-author), Master Jeong Se-hwan (First Co-author), Professor Kim Gyo-beom (Co-corresponding Author), and Professor Choi Min-jae (Co-corresponding Author), succeeded in near-infrared photothermal anticancer therapy.Photothermal anticancer therapy is a noninvasive therapy that applies light to a local area to induce heat generation to eradicate cancer cells selectively. The research team developed eco-friendly quantum dots without in vivo toxicity, used them in their research, and confirmed that they generate heat when irradiated with infrared rays and eradicate cancer cells. While most existing photothermal anticancer therapy uses gold nanoparticles, this research is characterized by using quantum dots.Professor Choi Min-jae’s team said, “Quantum dots are easy to control in the infrared area and have strong potential as the material for infrared photothermal therapy in the future, and we plan to develop photothermal therapies targeting various tumors through follow-up studies.”The research was funded by the National Research Foundation of Korea through the Basic Research Lab Support Project and Excellent New Research Project, and was published in the January 2024 edition of the renowned international academic journal ACS Materials Letters (IF=11.4) under the title “Dual-Ligand Surface Passivation Enables Monodisperse Ag2S Colloidal Quantum Dots for Efficient Near-Infrared Photothermal Therapy.”

Beyond Carbon: Scientists Design A New Catalyst to Generate Green Fuel from Water

Globally, the transition to greener sources of energy requires the use of efficient catalysts for fuel generation reactions. Now, scientists at Dongguk University have synthesized an efficient catalyst for the oxygen evolution reaction — a component of water-splitting process that produces hydrogen and oxygen. The catalyst, synthesized using molybdenum and ruthenium, exhibits high activity, reaction rates, and durability, opening doors to the cost-effective and large-scale production of next-generation catalysts using diverse materials.Chemical energy storage is a promising solution for circumventing the global energy challenges. Reduction of water to molecular hydrogen via the splitting water reaction is a key method. However, issues like low catalyst activity, slow reaction speed, and catalyst degradation pose challenges.Now, in a recent study led by Professor Young-Kyu Han and Assistant Professor Jitendra N. Tiwari from the Department of Energy and Materials Engineering at Dongguk University, scientists have developed an effective oxygen evolution reaction catalyst with molybdenum and ruthenium. Their study was made available online on July 29, 2023, and published in Volume 339 of Applied Catalysis B: Environmental on December 15, 2023. According to Prof. Han, “Carbon materials are crucial for commercial acidic polymer electrolyte membrane water electrolyzers. At high voltages, however, carbon atoms degrade in strongly acidic media, necessitating the need for new catalyst materials beyond carbon materials.”The study involved implanting ruthenium oxide into a two-dimensional molybdenum carbide to create a catalyst (Mo2TiC2Tx MXene) with high mass activity, turnover frequency, and durability. Calculations also indicated that the ruthenium sites had a strong affinity towards oxygen species, which enhanced the reaction.These findings are significant, as the global aim is to achieve 80% renewable electricity by 2050. Hydrogen and oxygen have diverse industrial applications, spanning clean fuel, power generation, chemical production, and life-support systems. Notably, more than 90% of hydrogen is in petroleum recovery and refining (47%) and ammonia production (45%) alone.The transportation sector will also benefit. Elaborating on this, Dr. Tiwari says, “The need for decarbonizing the transportation sector makes hydrogen a promising alternative. Going ahead, fuel cell vehicles are expected to efficiently convert hydrogen into electrical energy, emitting only water, with longer driving ranges than battery electric vehicles. Additionally, hydrogen fuel cells do not need recharging and don’t degrade if hydrogen fuel is present, unlike in batteries,” observes Dr. Tiwari.This study thus serves as a guide for researchers to create new catalysts for acidic water oxidation. It also sheds light on achieving cost-effective, large-scale catalyst production using diverse materials, such as dual-transition metal catalysts.ReferenceTitle of original paper: Atomic layers of ruthenium oxide coupled with Mo2TiC2Tx MXene for exceptionally high catalytic activity toward water oxidationJournal: Applied Catalysis B: EnvironmentalDOI: 10.1016/j.apcatb.2023.123139*Corresponding authors’ emails:ykenergy@dongguk.edu (Y.-K. Han), jnt_tiw123@yahoo.co.in (J.N. Tiwari), and yunsuk.huh@inha.ac.kr (Y.S. Huh)About 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 authorsProf. Jitendra N. Tiwari is an Assistant Professor at the Department of Energy and Materials Engineering, Dongguk University, Seoul. His research focuses on the development of carbon and MXene-based catalysts and their applications in energy. He has worked as a postdoctoral, senior scientist, and research-assistant professor at NCTU (Taiwan), POSTECH (Pohang) and UNIST (Ulsan).Prof. Young-Kyu Han is a Full Professor at the Department of Energy and Materials Engineering at Dongguk University, Seoul, Republic of Korea. His current research interests are the quantum simulations of battery and catalyst materials. He is also working on the design of new promising materials based on atomic-level simulation.

Sodium-Ion Batteries: The Future of Sustainable Energy Storage

Lithium-ion batteries (LIBs) have become essential for energy storage systems. However, limited availability of lithium has raised concerns about the sustainability of LIBs. In a new study, scientists from Dongguk University reviewed the recent advances in sodium-ion battery technology, a potential alternative to LIBs. Their findings can inspire young researchers to combat the current challenges of SIBs for their rapid commercialization.With the rapid increase in global energy demand and a growing shift toward renewable energy sources, lithium-ion batteries (LIBs) have become an indispensable part of our daily lives. However, the limited availability of lithium and the consequent increase in its costs have raised concerns about the sustainability of LIBs. As an alternative, sodium-ion batteries (SIBs) have gained considerable attention. SIBs offer many advantages, because their raw materials are naturally abundant, safe, and share a similar chemistry to the already mature LIB technology. However, despite these benefits, there are many challenges that impede the commercialization of SIBs.To highlight these challenges and their potential solutions, a multinational team of researchers led by Professor Kyung-Wan Nam from the Department of Energy and Materials Engineering at Dongguk University, Korea, recently reviewed the recent advances in SIB technology. “We believe that highlighting the advances and challenges of current SIB technology not only inspires young researchers but also provides valuable insights for enhancing the performance and commercialization of SIBs.” says Prof. Nam, while talking about the study. The study was made available online on July 4, 2023, and published in Volume 33, Issue 46 of the journal Advanced Functional Materials on November 9, 2023.The team identified the main research areas in SIB technology, emphasizing the development of cathode and anode materials, electrolytes, and full-cell configurations. While most studies till now have only focused on half-cell configurations, full-cell configurations for SIBs can serve as a long-term alternative to LIBs. Fortunately, emerging energy companies and many researchers are working toward realizing practical full-cell SIBs.The team also highlighted future research directions, urging to eliminate the use of toxic substances in cathodes and design of volume-controlled anodes. Furthermore, they also suggested that electrolytes will make significant improvements in both the cycle life and performance of SIBs.“While the cost of SIBs might be slightly lower and comparable to LIBs, the availability of sodium and the use of less toxic materials makes them a great alternative. In the long term, SIB can complement LIB technology, rather than being a competitor,” says Prof. Nam.The team expresses confidence that most of the current challenges will be addressed in the coming years, paving the way for a cleaner and greener tomorrow!ReferenceTitle of original paper: Unleashing the Potential of Sodium-Ion Batteries: Current State and Future Directions for Sustainable Energy StorageJournal: Advanced Functional MaterialsDOI: 10.1002/adfm.202304617*Corresponding authors’ emails: aditya@dongguk.edu (A.N.S.); knam@dongguk.edu (K.W.N.)About Dongguk UniversityWebsite: https://www.dongguk.edu/eng/

Manganese Complex Leads the Way to Affordable and Sustainable Bright White OLEDs

Scientists at Dongguk University have developed a new environmentally friendly and cost-effective bright green light-emitting manganese complex called MnBz for organic light-emitting diodes (OLEDs). The material was used to fabricate a first-of-its-kind Mn-based white OLED device and a green OLED device with record high efficiency.Organic light-emitting diodes (OLEDs) are considered new and promising light sources for illuminating digital displays and indoor/outdoor spaces. One of the most popular commercial methods for fabricating OLEDs is the solution processing approach. However, while the fabrication process of such LEDs itself is low-cost and simple, the raw materials used during solution process often include precious and expensive metals such as rare earth metals, driving up the fabrication costs.Studies have shown that low-dimensional complexes of earth-abundant transition metals could be the key to solving this problem. To develop a promising solution using this approach, a team of researchers led by Assistant Professor Vijaya Gopalan Sree from Dongguk University recently attempted to synthesize zero-dimensional manganese (Mn)-based complexes for OLEDs via solution processing. In their recent breakthrough made available online on 7 September 2023 and published in Volume 474 of the Chemical Engineering Journal on 15 October 2023, the team has laid out the strategy for fabricating a bright green-light-emitting Mn (II) complex MnBz, which was further utilized to design a first-of-its-kind warm-white OLED device."Replacing expensive rare earth metals like gold and platinum with crystalline earth-abundant transition metal complexes can help achieve lightning solutions or displays that are cheaper yet bright and vibrant,” says Dr. Sree, talking about their motivation to explore new materials for OLEDs.In this study, the researchers synthesized MnBz by subjecting manganese bromide (MnBr2) and benzyltriphenylphosphonium bromide (Ph3BzPBr) to solvent-free grinding, followed by dissolution in acetonitrile solvent. The resulting solution was slowly evaporated over days to obtain single crystals of MnBz. The thus obtained MnBz exhibited bright green-light emissions with a narrow emission spectrum and high quantum yield.The team then used the single crystals of MnBz to design a novel Mn(II) complex-based warm-white light-emitting device, which exhibited an excellent color rendering index (CRI) of 78. MnBz was also used to design a green phosphorescent OLED device, which exhibited excellent performance. These light emitters displayed a record-breaking quantum efficiency of 11.42% and current efficiency of 56.84 cd A-1.The exceptional brightness of these MnBz-based devices in response to low turn-on voltages can pave the way for energy-efficient OLED-based consumer electronics and lighting systems. Explaining further, Dr. Sree adds, “Our new eco-friendly and cost-effective light emitter can facilitate developments towards a wider adoption of OLEDs and ultimately impact people's lives by transforming the way we interact with and illuminate our world.”ReferenceTitle of original paper: Green and warm-white light-emitting diodes enabled by zero-dimensional green-emitting Mn(II) bromide complex with record high efficiencyJournal: Chemical Engineering JournalDOI: 10.1016/j.cej.2023.145936*Corresponding author’s email: hyunsik7@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: http://www.dongguk.edu/mbs/en/index.jspAbout the authorDr. Vijaya Gopalan Sree (first author) is currently an Assistant Professor in the Division of Physics and Semiconductor Science at Dongguk University, Seoul, South Korea. He received his D. Phil. degree from Pusan National University, Busan, South Korea (2015–2019) and formerly worked as a postdoctoral research associate at the Center for Superfunctional Materials, UNIST, Ulsan, South Korea (2019–2020). His research involves the design, engineering, and development of novel materials (organic and organometallic) that are cheaper and more efficient alternatives for applications in energy storage and optoelectronics.Prof. Hyunsik Im (corresponding author) received his D.Phil. degree in physics from the University of Oxford. After postdoctoral research in the Clarendon Laboratory at Oxford and Institute of Industrial Science at the University of Tokyo, he was appointed assistant professor in the Department of Physics and Semiconductor Science at Dongguk University in 2001, was promoted to full professor in 2011. His research areas include optoelectronic and mesoscopic physics in solid-state materials.(Webpage: https://sites.google.com/view/edlabdgu)

Graduate student Lee Jin-ho of the Department of Semiconductor Science Wins Hyundai Motor Chung Mong-Koo Scholarship

Lee Jin-ho of the Department of Semiconductor Science (Master's course) was selected as a Hyundai Motor Company Chung Mong-Koo Scholarship recipient.The Hyundai Motor Chung Mong-Koo Foundation held the '2023 Scholarship Ceremony and Graduation Ceremony' at the Ramada Seoul Sindorim Hotel on June 27.Lee Jin-ho received the scholarship for 'Intelligent Information Technology' in the field of future industry at the scholarship award ceremony.The student will receive various benefits once selected as a Hyundai Motor Chung Mong-Koo Scholarship student. Full tuition and living expenses are provided alongside growth support packages and networking programs. Additional scholarships are provided to students who publish papers in internationally renowned academic journals and win prizes in international competitions. Other scholarships are also offered for up to five years to a student who expands their activities overseas, such as entering an excellent university (graduate school) within the world’s top 100 universities to foster the scholarship student's growth continuously. Various networking programs, such as summer camp, performance viewing, and a homecoming day, are operated exclusively for the Hyundai Motor Chung Mong-Koo Scholarship students.The Hyundai Motor Chung Mong-Koo Foundation has operated the scholarship program since 2011 and renewed the 'Hyundai Motor Chung Mong-Koo Scholar' under the title 'Hyundai Motor Chung Mong-Koo Scholar' in 2021, reflecting its founder's will to foster talented people: 'Discovering talent builds national competitiveness.' Chung Mong-Koo is the honorary chairman of Hyundai Motor Group. The foundation has promoted the cultivation of 1,100 future talents over five years across six fields, including global future industry, international cooperation, social innovation, culture and arts, and social integration, and actively supported global activities.

Dongguk University Professor Choi Chang-soon’s Research Team Develops a Clothing-type Energy Harvester

Utilizing Commercialized Fibers, Harvesting External Mechanical Energy into Electrical EnergyDemonstrates the Possibility of Commercializing Wearable Devices with Self-driven Sensors that Detect Human Body MovementOnline Publication of the Latest Edition of ‘Nano Letters,’ a Renowned International Journal in the Nano Field (From left) Dongguk University Department of Energy and Materials Engineering Master Kim Joo-wan, Master Roh Joon-ho, Professor Shim Hyun-joon, and Professor Choi Chang-soon○ Dongguk University Department of Energy and Materials Engineering Master Kim Joo-wan (lead author), Master Roh Joon-ho (co-lead author), Professor Shim Hyun-joon (co-corresponding author), and Professor Choi Chang-soon (corresponding author) announced that they had developed an energy harvester in the form of clothing by coating commercial yarn with graphene.○ They announced that they overcame the limitations of existing research by developing a technology to develop an energy harvester that can function as clothing by mass-producing functional yarn through a simple and continuous process and weaving them.○ Existing mechano-electrochemical-based energy harvesters had many commercialization difficulties, such as expensive materials, complex processes, and mechanical properties unsuitable for direct clothing application. To solve this problem, Professor Choi Chang-soon's research team maintained clothing functionality by simply coating commercial yarn with graphene. In addition, the team reported a wearable energy harvester capable of reproducing mechanical energy repeatedly generated through the wearer's movements into valuable electrical energy through imparting electrical conductivity.○ For proper mechanical properties, fine fibers are twisted and entangled in commercial yarn. The research team led by Professor Choi Chang-soon used this special fiber structure to understand how mechanical energy from the outside may affect the surface area of an energy harvester, which then converts that mechanical energy into electrical energy using electrochemical principles. When woven into the clothing fabric, the produced harvester can be used as a sensor to track human movement. It can detect motion, particularly in direction and intensity, and it has demonstrated promise as a self-driven sensor that runs without external power.○ Professor Choi Chang-soon said, "It is significant that we developed an energy harvester that harvests mechanical energy continuously generated by human body movement into electrical energy, while maintaining the essence of a wearable device." He also expressed his hope that, through mass production, a low-cost process, and the potential for weaving, "it can be used in various fields as self-driven sensors that do not require an external energy device."○ The research results were published online in August 2023 in 「Nano Letters (IF=12.262)」, a renowned international journal in the field of materials, under the title <Hierarchically Plied Mechano-Electrochemical Energy Harvesting Using a Scalable Kinematic Sensing Textile Woven from a Graphene-Coated Commercial Cotton Yarn>.

Dongguk University Professor Kim Jong-pil's team develops innovative cell rejuvenation and regeneration technology using the world's first genetic scissors technology

Awakening in vivo dormant rejuvenation-inducing genes through CRISPR/dCas9 activatorChallenging the realization of a sophisticated and safe dream of immortality... Published in Aging Cell (IF11.5), a world-renowned academic journalCalico and Altos Labs, recently formed by Google and Amazon, are working on projects to fulfill the dream of immortality, with the overarching goal of extending life by turning the biological clock backward. Cell rejuvenation and regeneration technology, which induces rejuvenation by setting the biological clock of adult cells backward, is gaining tremendous attention globally.Professor Kim Jong-pil's team at Dongguk University has developed a technology that induces more sophisticated and safe cell rejuvenation and regeneration by delicately activating the endogenous dormant rejuvenation-inducing gene (Oct4) using cutting-edge gene editing/scissors technology for the first time in the world. The Oct4 gene is a dormant gene that is no longer expressed in adult cells, despite its importance in the early development of human embryos. Professor Kim Jong-pil's team confirmed that temporarily reactivating only the Oct4 gene to reset an elderly mouse's biological clock using gene editing/scissors technology-based gene expression induction technology in an aged mouse converted the aging-inducing proteins and epigenome to a younger state, rejuvenating them to the same condition as a young mouse.Because there are adverse effects that generate tumor growth and cancer induction, existing cell reprogramming technology has clear limits in creating therapeutic and human cell regeneration/rejuvenation treatment technology. To overcome the limitations of current technology, Professor Kim Jong-pil's team produced cell rejuvenation in old mice by triggering the expression of a single gene (Oct4) with sophisticated genetic scissors while avoiding the production of tumor-producing genes (c-Myc and Klf4). As a result, it was possible to minimize tumorigenic side effects while reliably and efficiently inducing rejuvenation in old cells and tissues, hence extending lifetime.For the first time in the world, Professor Kim Jong-pil, who was in charge of this research, could efficiently express in vivo dormant rejuvenation-inducing genes in cells and tissues using genetic scissors technology. This resulted in rejuvenation and regeneration in all tissues of the aging mouse. Notably, this method has been demonstrated to have the potential to be used for a variety of degenerative disorders. Above all, it presented a significant opportunity to use human disease treatment technologies via anti-aging rejuvenation.This study was published on March 25, 2023, in Aging Cell (IF: 11.5), a world-renowned academic publication, with funding from the pan-governmental regenerative medical technology project group and the university’s important research institution project.- Journal Title: Transcriptional activation of endogenous Oct4 via the CRISPR/dCas9 activator ameliorates Hutchinson-Gilford Progeria Syndrome in mice- Author Information: Kim Jong-pil (correspondent, Dongguk University professor), Kim Jun-yeop (first author, doctoral student), Hwang Ye-rim (first author, doctoral student)* For inquiries regarding this material, please contact the Dongguk University Department of Chemistry Professor Kim Jong-pil (02-2260-3321, jk2316@gmail.com).

A research team led by Professor Kwon Soon-Cheol at Dongguk University has enhanced cathode catalysts' work function and electrical conductivity for developing ultra-high-performance metal-air secondary batteries.

Successfully predicted electrical conductivity and energy level according to the relative fusion ratio.Synthesized high-performance dual-phase electrochemical catalyst, which layered a 6:4 ratio nickel-silver (Ag0.6Ni0.4) on a three-dimensional cobalt-niobium oxide (CoNb2O6) nanocube structure 1.4 times the charging capacity of existing Zn-Air (metal-air) secondary batteries and 3.8 times the stabilityPublished in the latest issue of ‘Applied Catalysis B: Environmental,’ the top international journal in the field of energy and environmentDemand continues to rise as the application fields for secondary batteries, such as mobile electronic gadgets and electric vehicles, expand. While traditional lithium-ion-based secondary batteries have such problems as the risk of explosion and limited charge capacity, Zn-Air (metal-air) batteries have several advantages, such as relatively high energy density, low cost, and high stability, and are regarded as superior secondary batteries when compared to existing lithium-ion batteries.However, a new highly active catalyst was developed because the carbon cathode employed for the air contact surface lacks an efficient electrochemical OER-ORR (oxygen generation-oxygen reduction reaction). As a result, because silver and nickel metals have outstanding electrochemical catalytic capabilities, research was needed to simultaneously improve battery performance and stability by maximizing their physical qualities by manufacturing them into a multi-metal alloy.A research team led by the Dongguk University Department of Energy and Materials Engineering Research Professor Bala (first author) and Professor Kwon Soon-cheol (corresponding author) successfully developed a new dual-phase cathode material catalyst material by layering multi-metal alloy nanoparticles (AgNi, nickel silver) alloyed in a specific ratio on a unique three-dimensional metal oxide nanocube structure (CoNb2O6, cobalt-niobium oxide).Professor Kwon's research team focused on the fact that the relative fusion ratio of AgNi multi-metal alloy catalysts can significantly contribute to electrical conductivity and energy level management and applied "Virtual Crystal Approximation" (VCA) based on density functional theory. As a result, when the relative fusion ratio of silver and nickel is 6:4, the maximum electrical conductivity (σ) is anticipated to reach ~2 x 107 S cm-1 and the work function -5.4 eV.Based on this knowledge, a three-dimensional nano cube structure (cobalt niobium oxide, CoNb2O6) capable of serving as an OER was hydrothermally synthesized. Through successive hydrothermal synthesis, nickel-silver metal multi-alloy nanoparticles in a 6:4 ratio that may play the role of ORR were uniformly stacked on top of this three-dimensional structure. Consequently, the research team could create a novel high-performance two-phase catalyst material.The two-phase catalyst material developed in this manner, in particular, is absorbed into the pores of the existing carbon cathode material, increasing the reaction surface area and facilitating electron, ion, and mass transfer, resulting in higher catalytic activity and Zn-Air (metal-air) battery performance when compared to the existing carbon electrode. The charging capacity of the Zn-Air battery using the two-phase catalyst material was 806.8 mAhg-1, which is more than 1.4 times greater than the 576.6 mAhg-1 of the Zn-Air battery using a single metal oxide catalyst. Furthermore, the charge/discharge performance of the two-phase catalyst Zn-Air battery was 587 hours, 3.8 times that of a single catalyst battery, due to an efficient and balanced OER-ORR reaction (156 hours)."Through this research, we have completed a technology that can maximize and stabilize the electrical and physical characteristics of the metal multi-alloy electrochemical catalyst based on the relative fusion ratio," said Professor Kwon Soon-cheol, " We were able to develop a new high-performance two-phase electrochemical catalyst material using this technology, which is absorbed on the existing carbon electrode to enable efficient/balanced OER-ORR (oxygen generation-oxygen reduction reaction) with a larger surface area, which is significant in realizing an ultra-high performance/stability next-generation Zn-Air secondary battery," and expected, "Because the developed carbon electrode, which includes the two-phase catalyst, operates consistently for 160 hours even in a pouch cell type, we will be able to move a step closer to commercialization of next-generation thin-film or flexible secondary batteries."This research was funded through the National Research Foundation of Korea's senior researcher support project and innovative and challenging research support project. The findings were published online on March 14, 2023, in Applied Catalysis B: Environmental (IF=24.319), the top international journal in the field of energy and environment, under the title <High-performance rechargeable metal-air batteries enabled by efficient charge transport in multielement random alloy electrocatalyst >.<Prediction of energy level and electrical conductivity according to the fusion ratio of AgNi (nickel silver) multi-metal alloy catalyst using “Virtual Crystal Approximation (VCA)”>(a) Prediction of crystal structure change depending on the relative fusion ratio of Ag and Ni(b), (c), (d) Prediction of changes in work function, electrical conductivity, and magnetic movement depending on the relative fusion ratio of Ag and Ni.* For inquiries regarding this material, please contact Dongguk University Professor Kwon Soon-cheol (02-2260-3678, kwansc12@dongguk.edu).

Dongguk University Professor Choi Chang-soon's research team develops high-performance carbon nanotube fibers

(1) Increased energy storage capacity (capacitance) twentyfold while also including energy harvesting characteristics by constructing a carbon nanotube corrugated structure that retains electrical/mechanical performance despite extreme stretchability. (2) Created fiber electrodes with improved mechanical drive and energy storage capacities by activating even the inside of porous carbon nanotube fibers."Published in outstanding academic journals in the field such as ‘Composite parts B: Engineering (IF=11.322, top 1.630% in JCR)’ and ‘ACS Applied Materials & Interfaces (IF=10.383, top 14.058% in JCR)"Professor Choi Chang-soon's research team created corrugated microstructure carbon nanotube composite fibers with up to 600% elasticity for use in conductors, supercapacitors, and energy harvesters.A research team led by Master Yoo Seong-joon (first author) and Professor Choi Chang-soon (corresponding author) from Dongguk University created a multi-functional fiber electrode by loading a carbon nanotube sheet onto polymer fibers to form micro-sized wrinkles on the surface. The carbon nanotube corrugated microstructure created in this way has high elasticity (600%) and conductivity, as well as the ability to form micro-sized pores from the contact surface of the polymer core, allowing for approximately 20 times higher capacitance compared to a plain structure without micro-wrinkles and mechano-electrochemistry-based energy production. The polymer/carbon nanotube corrugated microstructure, which can achieve several performance capabilities in a single structure, can be employed in various fields, including biosensors, energy harvesters, and energy storage devices.'This study is significant in that it demonstrated structural stability, mechanical elasticity, energy storage performance improvement, and energy harvesting in a single structure through the fabrication of the corrugated microstructure of carbon nanotubes,' said Professor Choi Chang-soon.Meanwhile, this research team recently completed another study on fiber-type carbon nanotube electrodes in collaboration with Hanyang University. By electrochemically activating up to the inside of the car's porous structure, a research team led by Professor Choi Chang-soon of Dongguk University's Department of Energy and Materials Engineering (corresponding author) and Professor Kim Seon-jeong of Hanyang University's Department of Electronic Engineering (co-corresponding author) succeeded in developing a carbon nanotube fiber electrode with dramatically improved mechanical drive and energy storage performance. Carbon nanotube fiber electrodes are promising electrode candidates with a wide range of applications because they have excellent mechanical and electrical properties as well as a unique structure that provides a highly effective reaction area due to the dense concentration of millions of nano-bundles aligned in a single direction and nano-micro channels between bundles. However, because of the stability of the carbon-to-carbon network, which does not react well with other materials, there were numerous practical restrictions.The existing technology is an oxygen plasma procedure that uses plasma to functionalize the carbon network exposed on the surface, and it proved unable to activate fiber electrodes with internal structures several tens of micrometers in size. The research team applied electrochemical voltage to tackle this challenge. The nano-micro channel's electrostatic pull and capillary action allow the reactant to penetrate and activate the carbon nanotube fiber electrode down to the deep region of the fiber. The produced fiber electrode demonstrated excellent water reactivity, high hydrophilicity with a contact angle of approximately 38°, excellent rotational driving performance in a humid environment (986 revolutions/m), and a capacitance approximately 25 times more than before treatment (72.8 mF/cm2).According to Professor Changsoon Choi, "This study is remarkable since it activated carbon nanotube fibers as a whole using a new technique known as electrochemical processing. It will be employed as a base electrode in various industries in the future, including soft robots, fabric batteries, and water/wet harvesting, and will represent a technical tipping point that will drastically improve device performance." Researcher Sohn Won-gyeong (co-first author) and Lee Jae-myeong (co-first author) participated in this research.<From left, Professor Choi Chang-soon, Master Yoo Seong-joon, Researcher Sohn Won-gyeong, Researcher Lee Jae-myeong of the Department of Energy and Materials Engineering>The research results were published in the March 2023 issue of 「Composites part B: Engineering (IF=11.322)」, a renowned international journal in the field of engineering, and 「ACS Applied Materials & Interfaces (IF=10.383)」, a journal in the field of nanoscience and technology.