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KAIST Develops a Fire-risk Free Self-Powered Hydrogen Production System
KAIST researchers have developed a new hydrogen production system that overcomes the current limitations of green hydrogen production. By using a water-splitting system with an aqueous electrolyte, this system is expected to block fire risks and enable stable hydrogen production.
KAIST (represented by President Kwang Hyung Lee) announced on the 22nd of October that a research team led by Professor Jeung Ku Kang from the Department of Materials Science and Engineering developed a self-powered hydrogen production system based on a high-performance zinc-air battery*.
*Zinc-air battery: A primary battery that absorbs oxygen from the air and uses it as an oxidant. Its advantage is long life, but its low electromotive force is a disadvantage.
Hydrogen (H₂) is a key raw material for synthesizing high-value-added substances, and it is gaining attention as a clean fuel with an energy density (142 MJ/kg) more than three times higher than traditional fossil fuels (gasoline, diesel, etc.). However, most current hydrogen production methods impose environmental burden as they emit carbon dioxide (CO₂).
While green hydrogen can be produced by splitting water using renewable energy sources such as solar cells and wind power, these sources are subject to irregular power generation due to weather and temperature fluctuations, leading to low water-splitting efficiency.
To overcome this, air batteries that can emit sufficient voltage (greater than 1.23V) for water splitting have been gaining attention. However, achieving sufficient capacity requires expensive precious metal catalysts and the performance of the catalyst materials becomes significantly degraded during prolonged charge and discharge cycles. Thus, it is essential to develop catalysts that are effective for the water-splitting reactions (oxygen and hydrogen evolution) and materials that can stabilize the repeated charge and discharge reactions (oxygen reduction and evolution) in zinc-air battery electrodes.
In response, Professor Kang's research team proposed a method to synthesize a non-precious metal catalyst material (G-SHELL) that is effective for three different catalytic reactions (oxygen evolution, hydrogen evolution, and oxygen reduction) by growing nano-sized, metal-organic frameworks on graphene oxide.
The team incorporated the developed catalyst material into the air cathode of a zinc-air battery, confirming that it achieved approximately five times higher energy density (797Wh/kg), high power characteristics (275.8mW/cm²), and long-term stability even under repeated charge and discharge conditions compared to conventional batteries.
Additionally, the zinc-air battery, which operates using an aqueous electrolyte, is safe from fire risks. It is expected that this system can be applied as a next-generation energy storage device when linked with water electrolysis systems, offering an environmentally friendly method for hydrogen production.
< Figure 1. Illustrations of a trifunctional graphene-sandwiched heterojunction-embedded layered lattice (G-SHELL) structure. Schematic representation of a) synthesis procedures of G-SHELL from a zeolitic imidazole framework, b) hollow core-layered shell structure with trifunctional sites for oxygen reduction evolution (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER), and c) heterojunctions, eterojunction-induced internal electric fields, and the corresponding band structure. >
Professor Kang explained, "By developing a catalyst material with high activity and durability for three different electrochemical catalytic reactions at low temperatures using simple methods, the self-powered hydrogen production system we implemented based on zinc-air batteries presents a new breakthrough to overcome the current limitations of green hydrogen production."
<Figure 2. Electrochemical performance of a ZAB-driven water-splitting cell with G-SHELL. Diagram of a self-driven water-splitting cell integrated by combining a ZAB with an alkaline water electrolyzer.>
PhD candidate Dong Won Kim and Jihoon Kim, a master's student in the Department of Materials Science and Engineering at KAIST, were co-first authors of this research, which was published in the international journal Advanced Science on September 17th in the multidisciplinary field of materials science. (Paper Title: “Trifunctional Graphene-Sandwiched Heterojunction-Embedded Layered Lattice Electrocatalyst for High Performance in Zn-Air Battery-Driven Water Splitting”)
This research was supported by the Nano and Material Technology Development Program of the Ministry of Science and ICT and the National Research Foundation of Korea’s Future Technology Research Laboratory.
2024.10.22 View 1149 -
Seoul Climate-Energy Conference Seeks Global Sustainability
(President Shin and Former UN Secretary General at the Seoul Climate Change-Energy Conference)
Global leaders from both the private and public sectors discussed creative ways to seek inclusive green growth and sustainable development at the Seoul Climate-Energy Conference on November 24 in Seoul. The annual conference was co-hosted by KAIST and the Coalition for Our Common Future under the theme “Creating New Momentum for the Paris Agreement and a Sustainable Future.”
More than 100 global leaders participated in the forum including the Director General Frank Rijsbermanof the Global Green Growth Institute and Executive Director Howard Bamsey of the Green Climate Fund. Former UN Secretary-General Ban Ki-Moon, who played a significant role in the signing of the Paris Agreement, was the keynote speaker.
This year’s conference focused on Korea’s low carbon-energy transition and the Fourth Industrial Revolution to be aligned with green growth. At the conference, speakers and participants reviewed the progress of the decisions made by the UN Framework Convention on Climate Change (UNFCCC) COP23 in Bonn, Germany. The conference discussed topics of global collaboration for new climate regimes, green energy infrastructure, the Asia super grid, financing green energy, smart green cities, and new mobility.
President Sung-Chul Shin emphasized global action and greater resilience toward climate change in his opening remarks. He said, “Today’s climate change can be attributed directly to the past three industrial revolutions. As industrialization continues, we must not make future generations pay the cost of this Fourth Industrial Revolution.” He explained that it is increasingly complicated to address climate change and energy issues because even though the use of energy consumption will continue to increase, energy policies are interwoven with global politics.
He stressed three keywords to better address this global problem: innovation, collaboration, and speed. First he emphasized innovation as a priority for future success as it is hard to retain confidence without innovation.
He noted KAIST has made sustainability initiatives in the fields of EEWS (energy, environment, water, sustainability) and green mobility. He also noted the importance of collaboration as industries are moving beyond a single discipline. KAIST is making collaborations in R&D and sustainability sectors, such as Saudi Aramco’s CO2 management center in KAIST. Finally, he explained that the speed of new transformation will be beyond our imagination, and governments should work efficiently to address issues in a fast manner.
Meanwhile, Secretary-General Ban called for global unity in addressing climate change. He strongly emphasized that countries should make agreements not of willingness but of action, and that politicians should realize that this global agenda should be given top priority above domestic politics. He addressed how the world is experiencing the most powerful and destructive effects of climate change which makes active participation in the Paris Agreement increasingly important.
He expressed his concern that the richest and most powerful countries are backing off, emphasizing the role of these countries as both global leaders and top producers of CO2. He also shared his hopes that the OECD will continue to work to fill the absence of the United States, and stressed the importance of acquiring 10 billion USD by 2020 to fund mitigation and adaptation technologies for developing countries’ CO2 emissions.
Click for President Shin's opening remarks
2017.11.29 View 7392 -
KATT Tops at Appropriate Technology Competition
The KAIST Appropriate Technology Team (KATT) consisting of KAIST international students received gold and bronze awards at ‘the 9th Creative Design Competition for the Other 90%’. This year’s competition was hosted by the Ministry of Science, ICT and Future Planning at Seoul National University’s Global Convention Plaza on May 26. Undergraduate and graduate students nationwide formed 65 teams to participate in the competition.
The aim of the competition is to discover appropriate technology and sustainable design items to enhance quality of life for those with no or little access to science technology and its products around the world. This year’s competition categorized the designs into IT; water and energy; agriculture, hygiene, safety, and housing; and education. The teams were evaluated on their presentations and prototypes.
KATT produced alarm warning bracelets for people in developing countries and smart hybrid dryers for agricultural products. The alarm warning bracelets were designed for those living in tsunami risk zones; they use wireless communication technology to receive and transmit warning signals and can be produced for less than $4.
The smart hybrid dryers featured solar energy generation, aimed to help those with low income in subtropical, low-altitude regions with unstable climates, since there are currently no drying methods for agricultural products without direct exposure to sunlight. Therefore, the hybrid dryers allowed drying regardless of the weather, and thus increased the storage and distribution efficiency of agricultural products.
Ashar Alam from India who participated in developing the alarm warning bracelet said, “Through the appropriate technology club, I recognized problems in India that also affect neighboring countries such as Indonesia and Bangladesh. I wanted to actively use the science and technology knowledge I have accumulated in KAIST for the less fortunate.” He continued, “It was meaningful to develop the product using the respective talents of students from various countries with the spirit of developing appropriate technology.”
(Photo caption: Alarm warning bracelet team received the gold award)
2017.06.12 View 6829 -
13 KAIST Faculty Named as Inaugural Members of Y-KAST
The Korean Academy of Science and Technology (KAST) launched the Young Korean Academy of Science and Technology (Y-KAST) and selected 73 scientists as its inaugural members on February 24. Among them, 13 KAIST faculty were recognized as the inaugural members of Y-KAST.
Y-KAIST, made up of distinguished mid-career scientists under the age of 45, will take the leading role in international collaboration as well as innovative agenda-making in science and technology.
The inaugural members include Professor Hyotcherl Ihee of the Department of Chemistry and Dr. Sung-Jin Oh of the Center for Mathematical Challenges at the Korea Institute for Advanced Study (KIAS), affiliated with KAIST. Professor Ihee is gaining wide acclaim in the fields of physics and chemistry, and in 2016, Dr. Oh was the youngest ever awardee of the Presidential Award of Young Scientist.
The other Y-KAIST members are as follows: Professors Haeshin Lee of the Department of Chemistry; Mi Young Kim, Byung-Kwan Cho, and Ji-Joon Song of the Department of Biological Sciences; Song-Yong Kim of the Department of Mechanical Engineering; Sang-il Oum of the Department of Mathematical Sciences; Jung Kyoon Choi of the Department of Bio and Brain Engineering; Seokwoo Jeon, Sang Ouk Kim, and Il-Doo Kim of the Department of Materials Science and Engineering; Jang Wook Choi of the Graduate School of EEWS (Energy, Environment, Water and Sustainability); and Jeong Ho Lee of the Graduate School of Medical Science and Engineering.
The leading countries of the Academy of Science, which include Germany, Sweden, Belgium, Canada, and Japan, have established the Young Academy of Science since 2010 in order to encourage the research activities of their young scientists and to establish a global platform for collaborative research projects through their active networking at home and abroad.
President Myung-Chul Lee of KAST said, “We will spare no effort to connect these outstanding mid-career researchers for their future collaboration. Their networking will make significant impacts toward their own research activities as well as the global stature of Korea’s science and technology R&D.
(Photo caption: Members of Y-KAST pose at the inaugural ceremony of Y-KAST on February 24.)
2017.03.02 View 15399 -
Professors Jeon and Choi Receive the Young Scientist Award
Professors Seokwoo Jeon of the Department of Materials Science and Engineering and Jang Wook Choi of the Graduate School of Energy, Environment, Water and Sustainability (EEWS) at KAIST received the Young Scientist Award.
The award ceremony took place at the Korea Press Center in Seoul. Presented by the Ministry of Science, ICT and Future Planning of Korea and the National Academy of Engineering of Korea, the Young Scientist Award is given to outstanding scientists under the age of 40 who have demonstrated excellence in their research in the field of natural science.
Each year the award is given to three scientists in different areas.
Professor Jeon was recognized for his achievement in creating a new property of materials. He studied synthesis and development of low-dimensional nanomaterials and developed a large area nanostructure.
Professor Choi’s research area was to discover optimal materials for rechargeable batteries. By applying his research, he developed rechargeable batteries with high efficiency, making the wearable system more feasible.
2016.01.11 View 10090 -
Professors Sukbok Chang and Jang-Wook Choi Receive the 2015 Knowledge Award from the Korean Government
The Ministry of Science, ICT and Future Planning (MISP) of the Republic of Korea announced the 2015 Knowledge Awards on October 20, 2015. Two KAIST professors received the award.
Established in 2009, the awards are presented to Korean scientists whose publications have contributed to the international science community. Specifically, the MISP used the two biggest science databases, Science Citation Index Expanded (SCIE) and Scopus, to identify ten highly cited papers ranked in the top 1% by total citations in the past ten years.
Professor Sukbok Chang of Chemistry (left in the picture below) is a global authority in the field of catalytic hydrocarbon functionalization. His paper entitled “Palladium-catalyzed C-H Functionalization of Pyridine N-Oxides: Highly Selective Alkenylation and Direct Arylation with Unactivated Arenes,” which was published in the Journal of the American Chemical Society in 2008, was once selected by Thomson Reuters as one of the “Most Influential Research Papers of the Month.” In 2011, the American Chemical Society included his paper in the list of the top 20 research papers that were most frequently cited in the last three years.
Professor Jang-Wook Choi of the Graduate School of EEWS (Energy, Environment, Water, and Sustainability) has been known for his leading research in rechargeable battery, supercapacitor, and materials chemistry. In particular, his work on secondary fuel cells attracted significant attention from academia and industry in Korea. Professor Choi developed a super-thin flexible lithium-ion battery this year, thinner than a credit card, which lasts longer than the existing batteries and with greater performance. He also developed new electrode materials for next-generation sodium-ion and magnesium secondary fuel cells.
Professor Sukbok Chang (left) and Professor Jang-Wook Choi (right)
2015.10.23 View 9953 -
KAIST and the International Institute for Applied Systems Analysis Agree to Cooperate
KAIST signed a cooperation agreement with the International Institute for Applied Systems Analysis (IIASA) on October 29, 2014 at the president’s office.
Established in 1972 and based in Austria as a non-governmental research organization, IIASA is an international scientific institute that conducts policy-oriented research into global problems such as climate change, energy security, or population aging. IIASA examines such issues and devises strategies for cooperative action unconstrained by political and national self-interest.
Dr. Pavel Kabat, the Director General and CEO of IIASA, headed a delegation that visited KAIST to attend the signing ceremony of the agreement. He said, “KAIST has been known as a leading research university, and its strength in the development of green technology and environmental policy will benefit our institution. In particular, we expect to see vibrant exchanges of knowledge and researchers with the Graduate School of Green Growth (GSGG) and the Graduate School of EEWS (energy, environment, water, and sustainability) at KAIST.”
The two organizations will implement joint research projects in the diffusion analysis of green technology, the development and improvement of evaluation models to integrate economy, energy, and environment, the development of an analysis system for water resources, and the establishment of academic workshops and conferences.
The Dean of GSGG, Professor Jae-Kyu Lee said, “IIASA is a well-respected international organization with accumulated knowledge about analysis and prediction techniques. With this agreement, we hope that KAIST will intensify its research capacity in environmental science and lead education and research in green growth and environmental technology.”
The picture below shows Dr. Pavel Kabat, the Director General and CEO of IIASA, on the left and President Steve Kang of KAIST on the right holding the signed agreement with professors from GSGG and EEWS Graduate School including Professor Jae-Kyu Lee, to the right of President Kang.
2014.11.05 View 9543 -
Development of a Photonic Diode with Light Speed, Single-Direction Transfer
A photonic diode using a nitride semiconductor rod can increase the possibility of developing all-optical integrated circuits, an alternative to conventional integrated circuits.
Professor Yong-Hoon Cho's research team from the Department of Physics, KAIST, developed a photonic diode which can selectively transfer light in one way, using semiconductor rods.
The photonic diode has a diameter of hundreds of nanometers (nm) and a length of few micrometers. This size enables its use in large-scale integration (LSI). The diode’s less sensitivity towards polarized light angle makes it more useful.
In an integrated circuit, a diode controls the flow of electrons. If this diode controls light rather than electrons, data can be transferred at high speed, and its loss is minimized to a greater extent. Since these implementations conserve more energy, this is a very promising future technology.
However, conventional electronic diodes, made up of asymmetric meta-materials or photonic crystalline structures, are large, which makes them difficult to be used in LSI. These diodes could only be implemented under limited conditions due to its sensitivity towards polarized light angle.
The research team used nitride semiconductor rods to develop a highly efficient photonic diode with distinct light intensities from opposite ends.
The semiconductor rod yields different amount of energy horizontally. According to the research team, this is because the width of the quantum well and its indium quantity is continuously controlled.
Professor Cho said, "A large energy difference in a horizontal direction causes asymmetrical light propagation, enabling it to be operated as a photonic diode." He added that “If light, instead of electrons, were adopted in integrated circuits, the transfer speed would be expected as great as that of light.”
The research findings were published in the September 10th issue of Nano Letters as the cover paper.
Under the guidance of Professor Cho, two Ph.D. candidates, Suk-Min Ko and Su-Hyun Gong, conducted this research. This research project was sponsored by the National Research Foundation of Korea and KAIST’s EEWS (energy, environment, water, and sustainability) Research Center.
Figure Description: Computer simulated image of photonic diode made of semiconductor rod implemented in an all-optical integrated circuit
2014.09.23 View 10270 -
Book Announcement: Sound Visualization and Manipulation
The movie
Gravity
won seven Oscar awards this year, one of which was for its outstanding 3D sound mixing, immersing viewers in the full experience of the troubled space expedition.
3D audio effects are generated by manipulating the sound produced by speakers, speaker-arrays, or headphones to place a virtual sound source at a desired location in 3D space such as behind, above, or below the listener's head.
Two professors from the Department of Mechanical Engineering at KAIST have recently published a book that explains two important technologies related to 3D sound effects: sound visualization and manipulation.
Professor Yang-Hann Kim, an eminent scholar in sound engineering, and Professor Jung-Woo Choi collaborated to write Sound Visualization and Manipulation (Wily 2013), which uniquely addresses the two most important problems in the field in a unified way.
The book introduces general concepts and theories and describes a number of techniques in sound visualization and manipulation, offering an interrelated approach to two very different topics: sound field visualization techniques based on microphone arrays and controlled sound field generation techniques using loudspeaker arrays.
The authors also display a solid understanding of the associated physical and mathematical concepts applied to solve the visualization and manipulation problems and provide extensive examples demonstrating the benefits and drawbacks of various applications, including beamforming and acoustic holography technology.
The book will be an excellent reference for graduate students, researchers, and professionals in acoustic engineering, as well as in audio and noise control system development.
For detailed descriptions of the book:
http://as.wiley.com/WileyCDA/WileyTitle/productCd-1118368479.html
2014.03.10 View 11687 -
Observation of a water strider led to a new method of measuring properties of Nano films
Even the mechanical properties of Nano films of a few nanometers thick can be measured
Posted online Nature Communications on the 3rd of October
The joint research team of KAIST’s Department of Mechanical Engineering’s Professor Taek-Soo Kim and Doctor Seung-Min Hyun of the Nano mechanics laboratory of Korea Institute of Machinery and Materials has developed a new method to evaluate mechanical properties of Nano films using the characteristics of water surfaces.
The research findings have been posted on the online edition of Nature Communications on the 3rd of October. The technology can obtain accurate results by directly measuring the mechanical properties such as the strength and elasticity of Nano films. Academia and the industry expect the simplicity of the technology to present a new paradigm in the evaluation of mechanical properties of Nano films.
Evaluation of the mechanical properties of Nano films is essential not only in predicting the reliability of semiconductors and displays, but also in finding new phenomena in the Nano world. However, mechanical strength was difficult to test since the test demands the falling of objects to the ground to measure their strength, and nano films can easily break in the process.
The research team observed insects such as water striders freely floating on the surface of the water. The team used the properties of water, large surface tension and low viscosity, to float a 55 nanometers (nm) gold Nano film to successfully measure its mechanical properties without damaging it. The technology could be used to measure the mechanical properties of not only various types of Nano films but also films only a few nm thick.
Professor Taek-Soo Kim said, “We effectively performed an evaluation of the mechanical characteristics of Nano films, which was difficult in the past, by developing a new strength test using the properties of water.” He continued to say, “The team plans to discover the mechanical properties of 2D Nano films such as graphene that could not have been measured with the existing strength test methods.”
The research by KAIST’s Department of Mechanical Engineering’s graduate student Jae-Han Kim (lead author) under the supervision of Professor Taek-Soo Kim and Doctor Seung-Min Hyun of Korea Institute of Machinery and Materials was sponsored by the National Research Foundation of Korea.
Evaluation process of mechanical properties of Nano films by using the characteristics of water surfaces
Dr Seung-Min Hyun, Jae-Han Kim, and Professor Taek-Soo Kim from left to right
2013.11.11 View 8052 -
3rd EEWS CEO Forum Held
KAIST EEWS (Energy Environment Water and Sustainability) held the 3rd EEWS CEO Forum at KAIST Seoul Campus.
EEWS is a research/education project initiated by KAIST to solve the global issues that the world faces including issues such as: energy depletion, global warming, water shortage, and sustainable development.
The 3rd EEWS CEO Forum is dedicated to providing the opportunity to share the vision and experience on technology and policy for green growth. The forum was founded in 2011 with active participation from Woo Ki Jeong (Director of Statistics), Choi Kwang Sik (Korea City Airport, Logistics and Travel, CEO), Kang Young Joong (Daekyo Group, CEO), Yoo Kyung Sun (Eugene Group, CEO), all experts in the field of green growth.
The forum consisted of presentations and debate on topics such as: international outlook on green growth, development projects based on new renewable energy, battery of electric vehicles, and development of solar cells.
Kim Sang Hyup member of the Presidential Committee on Green Growth started off the series of lectures with the topic of ‘International Outlook on Green Growth’. Kim Joong Gyum CEO of KEPCO followed up with ‘the Future of Electricity Generation Industry and Renewable Energy’, Kim Soo Ryung Director of LG Chemicals gave a talk on ‘Electric Vehicles and the Future of the Battery Industry’, and finally Choi Gi Hyuk CEO of SDN Ltd. gave the final lecture on ‘the Inflection Point of Solar Cell Industry’.
2012.10.16 View 9031 -
MOU on Joint Research Program with KUSTAR
KAIST has signed a MOU on Joint Research Program with KUSTAR (Khalifa, University of Science, Technology, and Research).
The Signing ceremony was held in UAE Abu Dhabi with KAIST President Seo Nam Pyo and KUSTAR Presdient Tod Laursen in attendance.
The MOU contains agreements on seed money project, exchange professors and students program, seminars and workshops, and cooperative closely through funding joint research facilities among other key agreements.
The two universities are considering joint research on educational nuclear power plant simulator, research use nuclear reactor plans and nuclear reactor for saltwater desalination plants. In addition, the field of cooperation will not be limited to nuclear power, but will be broadened to electric and electronic, mechanical engineering, aeronautical engineering, industrial engineering, construction environment, and other fields by appointing KAIST professors to perform educational cooperation programs at KUSTAR.
The cooperation is part of the agreement made by the two respective countries in the Korea export of nuclear power plants to UAE in 2009. KAIST will be helping KUSTAR to develop into a world leading science and technology based education and research institute for the next 10 years.
2011.03.25 View 11431