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News Article on the Development of Synthesis Process for Graphene Quantum Dots Before It's News, an international online news agency, highlighted the recent research conducted by KAIST professors (Seokwoo Jeon of the Department of Materials Science and Engineering, Yong-Hoon Cho of the Department of Physics, and Seunghyup Yoo of the Department of Electrical Engineering) on the development of synthesis process for graphene quantum dots, nanometer-sized round semiconductor nanoparticles that are very efficient at emitting photons. If commercialized, this synthetic technology will lead the way to the development of paper-thin displays in the future. For the article, please go to the link below: Before It’s News, September 3, 2014“Graphene quantum dots prove highly efficient in emitting light” http://beforeitsnews.com/science-and-technology/2014/09/graphene-quantum-dots-prove-highly-efficient-in-emitting-light-2718190.html
2014.09.07 View 16388
Extracting Light from Graphite: Core Technology of Graphene Quantum Dots Display Developed Professor Seokwoo Jeon of the Department of Materials Science and Engineering, Professor Yong-Hoon Cho of the Department of Physics, and Professor Seunghyup Yoo of the Department of Electrical Engineering announced that they were able to develop topnotch graphene quantum dots from graphite. Using the method of synthesizing graphite intercalation compound from graphite with salt and water, the research team developed graphene quantum dots in an ecofriendly way. The quantum dots have a diameter of 5 nanometers with their sizes equal and yield high quantum efficiency. Unlike conventional quantum dots, they are not comprised of toxic materials such as lead or cadmium. As the quantum dots can be developed from materials which can be easily found in the nature, researchers look forward to putting these into mass production at low cost. The research team also discovered a luminescence mechanism of graphene quantum dots and confirmed the possibility of commercial use by developing quantum dot light-emitting diodes with brightness of 1,000 cd/m2, which is greater than that of cellphone displays. Professor Seokwoo Jeon said, “Although quantum dot LEDs have a lower luminous efficiency than existing ones, their luminescent property can be further improved” and emphasized that “using quantum dot displays will allow us to develop not only paper-thin displays but also flexible ones.” Sponsored by Graphene Research Center in KAIST Institute for NanoCentury, the research finding was published online in the April 20th issue of Advanced Optical Materials. Picture 1: Graphene quantum dots and their synthesis Picture 2: Luminescence mechanism of graphene quantum dots Picture 3: Structure of graphene quantum dots LED and its emission
2014.09.06 View 21080
A KAIST startup, YBrain, builds a wearable device to cure Alzheimer's A group of KAIST graduates from the Departments of Bio and Brain Engineering, Computer Science, Materials Science Engineering, and Industrial Design created a startup called YBrain (http://ybrain.com/). YBrain develops a wearable neuroscience technology to treat or reduce the symptoms of degenerative brain diseases such as dementia and Alzheimer’s. Their recent technological developments were covered in e27, one of the leading blogs based in Singapore. The blog covers topics like the latest technology innovation, startups, and entrepreneurship in Asia. A news article follows below: e27, June 24, 2014 “This wearable tech may be able to combat effects of Alzheimer’s” http://e27.co/this-wearable-tech-may-be-able-combat-effects-of-alzheimers-20140624/
2014.06.25 View 14735
The First Demonstration of a Self-powered Cardiac Pacemaker As the number of pacemakers implanted each year reaches into the millions worldwide, improving the lifespan of pacemaker batteries has been of great concern for developers and manufacturers. Currently, pacemaker batteries last seven years on average, requiring frequent replacements, which may pose patients to a potential risk involved in medical procedures. A research team from the Korea Advanced Institute of Science and Technology (KAIST), headed by Professor Keon Jae Lee of the Department of Materials Science and Engineering at KAIST and Professor Boyoung Joung, M.D. of the Division of Cardiology at Severance Hospital of Yonsei University, has developed a self-powered artificial cardiac pacemaker that is operated semi-permanently by a flexible piezoelectric nanogenerator. The artificial cardiac pacemaker is widely acknowledged as medical equipment that is integrated into the human body to regulate the heartbeats through electrical stimulation to contract the cardiac muscles of people who suffer from arrhythmia. However, repeated surgeries to replace pacemaker batteries have exposed elderly patients to health risks such as infections or severe bleeding during operations. The team’s newly designed flexible piezoelectric nanogenerator directly stimulated a living rat’s heart using electrical energy converted from the small body movements of the rat. This technology could facilitate the use of self-powered flexible energy harvesters, not only prolonging the lifetime of cardiac pacemakers but also realizing real-time heart monitoring. The research team fabricated high-performance flexible nanogenerators utilizing a bulk single-crystal PMN-PT thin film (iBULe Photonics). The harvested energy reached up to 8.2 V and 0.22 mA by bending and pushing motions, which were high enough values to directly stimulate the rat’s heart. Professor Keon Jae Lee said: “For clinical purposes, the current achievement will benefit the development of self-powered cardiac pacemakers as well as prevent heart attacks via the real-time diagnosis of heart arrhythmia. In addition, the flexible piezoelectric nanogenerator could also be utilized as an electrical source for various implantable medical devices.” This research result was described in the April online issue of Advanced Materials (“Self-Powered Cardiac Pacemaker Enabled by Flexible Single Crystalline PMN-PT Piezoelectric Energy Harvester”: http://onlinelibrary.wiley.com/doi/10.1002/adma.201400562/abstract). Youtube link: http://www.youtube.com/watch?v=ZWYT2cU_Mog&feature=youtu.be Picture Caption: A self-powered cardiac pacemaker is enabled by a flexible piezoelectric energy harvester.
2014.06.25 View 18782
Professor Sang Ouk Kim Receives the "Scientist of the Month Award" from the Korean Government Professor Sang Ouk Kim of the Department of Materials Science and Engineering, KAIST, received the Scientist of the Month Award in June 2014 for his development of a fundamental technology that allows free control of the properties of carbon-based materials. Since June 1997, the Korean government has awarded monthly one scientist working in industry, universities, or research institutions to recognize his or her research achievements, as well as to promote science and technology. Professor Kim implemented a technique known as doping, which has been used in ordinary semiconductor processes, to demonstrate the physical properties of carbon-based materials. Carbon nanotubes, graphene, and other carbon materials have superior mechanical and electrical properties and are regarded as next-generation materials. However, difficulty in controlling their qualities has made applications in various devices unfavorable. The doping technique in semiconductor production is to artificially introduce impurities into an extremely pure semiconductor for the purpose of modulating its electrical properties. Profess Kim doped elements like nitrogen and boron to enable minute control of the physical properties of carbon-based materials and applied the technique to development of organic solar cells, organic light-emitting devices, and flexible memory. He also increased the application range by using a self-assembly method to change freely the structure of carbon-based materials. Professor Kim has published 53 papers in renowned journals such as Advanced Materials and Nanoletters. He was rewarded further by being invited to write a review paper for the 25th anniversary special edition for Advanced Materials.
2014.06.19 View 12202
Professor Sang-Ouk Kim's Research on Carbon Materials Featured in a Philippines Science News The subject article said that Professor Sang-Ouk Kim of Materials Science Engineering at KAIST “developed a technique to change the nature of the next-generation carbon-based materials. His research has expanded the possibility of carbon-based materials to be used in clothes.” For details, please refer to the article below: Centrio Times, June 10, 2014 KAIST scientist develops color changing carbon materials that can be used in clothes http://www.centriotimes.com/2014/06/kaist-scientist-develops-color-changing-carbon-materials-can-used-clothes.html.
2014.06.15 View 9584
KAIST Made Great Improvements of Nanogenerator Power Efficiency The energy efficiency of a piezoelectric nanogenerator developed by KAIST has increased by almost 40 times, one step closer toward the commercialization of flexible energy harvesters that can supply power infinitely to wearable, implantable electronic devices. NANOGENERATORS are innovative self-powered energy harvesters that convert kinetic energy created from vibrational and mechanical sources into electrical power, removing the need of external circuits or batteries for electronic devices. This innovation is vital in realizing sustainable energy generation in isolated, inaccessible, or indoor environments and even in the human body. Nanogenerators, a flexible and lightweight energy harvester on a plastic substrate, can scavenge energy from the extremely tiny movements of natural resources and human body such as wind, water flow, heartbeats, and diaphragm and respiration activities to generate electrical signals. The generators are not only self-powered, flexible devices but also can provide permanent power sources to implantable biomedical devices, including cardiac pacemakers and deep brain stimulators. However, poor energy efficiency and a complex fabrication process have posed challenges to the commercialization of nanogenerators. Keon Jae Lee, Associate Professor of Materials Science and Engineering at KAIST, and his colleagues have recently proposed a solution by developing a robust technique to transfer a high-quality piezoelectric thin film from bulk sapphire substrates to plastic substrates using laser lift-off (LLO). Applying the inorganic-based laser lift-off (LLO) process, the research team produced a large-area PZT thin film nanogenerators on flexible substrates (2cm x 2cm). “We were able to convert a high-output performance of ~250 V from the slight mechanical deformation of a single thin plastic substrate. Such output power is just enough to turn on 100 LED lights,” Keon Jae Lee explained. The self-powered nanogenerators can also work with finger and foot motions. For example, under the irregular and slight bending motions of a human finger, the measured current signals had a high electric power of ~8.7 μA. In addition, the piezoelectric nanogenerator has world-record power conversion efficiency, almost 40 times higher than previously reported similar research results, solving the drawbacks related to the fabrication complexity and low energy efficiency. Lee further commented, “Building on this concept, it is highly expected that tiny mechanical motions, including human body movements of muscle contraction and relaxation, can be readily converted into electrical energy and, furthermore, acted as eternal power sources.” The research team is currently studying a method to build three-dimensional stacking of flexible piezoelectric thin films to enhance output power, as well as conducting a clinical experiment with a flexible nanogenerator. This research result, entitled “Highly-efficient, Flexible Piezoelectric PZT Thin Film Nanogenerator on Plastic Substrates,” was published as the cover article of the April issue of Advanced Materials. (http://onlinelibrary.wiley.com/doi/10.1002/adma.201305659/abstract) YouTube Link: http://www.youtube.com/watch?v=G_Fny7Xb9ig Over 100 LEDs operated by self-powered flexible piezoelectric thin film nanogenerator Flexible PZT thin film nanogenerator using inorganic-based laser lift-off process Photograph of large-area PZT thin film nanogenerator (3.5cm × 3.5cm) on a curved glass tube and 105 commercial LEDs operated by self-powered flexible piezoelectric energy harvester
2014.05.19 View 16471
Clear Display Technology Under Sunlight Developed The late Professor Seung-Man Yang The last paper of the late Professor Seung-Man Yang, who was a past master of colloids and fluid mechanics Practical patterning technology of the next generation optical materials, photonic crystals The mineral opal does not possess any pigments, but it appears colorful to our eyes. This is because only a particular wavelength is reflected due to the regular nano-structure of its surface. The material that causes selective reflection of the light is called photonic crystals. The deceased Professor Seung-Man Yang and his research team from KAIST’s Chemical and Biomolecular Engineering Department ha ve developed micro-pattern technology using photolithographic process. This can accelerate the commercialization of photonic crystals, which is hailed as the next generation optics material. The research results were published in the April 16th edition of Advanced Materials, known as the most prestigious world-renowned journal in the field of materials science. The newly developed photonic crystal micro-pattern could be used as a core material for the next generation reflective display that is clearly visible even under sunlight. Since it does not require a separate light source, a single charge is enough to last for several days. Until now, many scientists have endeavored to make photonic crystals artificially, however, most were produced in a lump and therefore lacked efficiency. Also, the low mechanical stability of the formed structure prevented from commercialization. In order to solve these problems, the research team has copied the nano-structure of opals. Glass beads were arranged in the same nano-structure as the opal on top of the photoresist material undergoing photocuring by ultraviolet light. The glass beads were installed in the photoresist materials, and UV light was selectively exposed on micro regions. The remaining region was developed by photolithographic process to successfully produce photonic crystals in micro-patterns. The co-author of the research, KAIST Chemical and Biomolecular Engineering Department’s Professor Sin-Hyeon Kim, said, “Combining the semiconductor process technology with photonic crystal pattern technology can secure the practical applications for photonic crystals.”He also predicted “This technology can be used as the key optical material that configures the next generation reflective color display device with very low power consumption.” The late Professor Seung-Man Yang was a world-renowned expert in the field of colloids and fluid mechanics. Professor Yang published over 193 papers in international journals and continued his research until his passing in last September. He received Du Pont Science and Technology Award in 2007, KAIST Person of the Year 2008, Gyeong-Am Academy Award in 2009, as well as the President’s Award of the Republic of Korea in March 2014. The researchers devoted the achievement of this year’s research to Professor Yang in his honor. Research was conducted by KAIST Photonic-fluidic Integrated Devices Research Team, as a part of the Creative Research Program funded by the Ministry of Science, ICT and Future Planning, Republic of Korea. Figure 1. Opal [left] and the nano glass bead arrangement structure within the opal [right] Figure 2. Process chart of the photonic crystal micro-pattern formation based on photolithography Figure 3. Opal structure [left] and inverted structure of the opal [right] Figure 4. Photonic crystal micro-pattern in solid colors Figure 5. Photonic crystal micro-pattern that reflects two different crystals (Red, Green) [left] and pixelated pattern of photonic crystal in three primary colors (Red, Green, Blue) [right] that is applicable to reflective displays
2014.05.14 View 14898
Yong-Joon Park, doctoral student, receives the Korea Dow Chemical Award 2014 Yong-Joon Park, a Ph.D. candidate of Materials Science and Engineering at KAIST, received the Korea Dow Chemical Award 2014, a prestigious recognition of the year’s best paper produced by students in the field of chemistry and materials science. The award ceremony took place on April 18, 2014 at Ilsan Kintex, Republic of Korea. The Korea Dow Chemical Award is annually given by Korea Dow Chemical and the Korean Chemical Society to outstanding papers produced by graduate and postdoc students. This year, a total of nine papers were selected out of 148 papers submitted. The title of Park’s paper is “The Development of 3D Nano-structure-based New Concept Super-elastic Materials.” This material could be used in flexible electronic devices such as displays and wearable computers.
2014.05.03 View 10442
Professor Sang-Ouk Kim Publishes Review Article in the Journal of "Nature Materials" Nature Materials, a peer-reviewed scientific journal published by Nature Publishing Group, covers a range of topics within materials science from materials engineering and structural materials. The journal invited Professor Sang-Ouk Kim of Materials Science and Engineering at KAIST to contribute to the April issue of 2014. Professor Kim, together with his doctoral student, Ju-Young Kim, wrote a review article in the “News and Views” section of the journal, which was entitled “Liquid Crystals: Electric Fields Line Up Graphene Oxide.” The News and Views is a peer-reviewed section where an academic authority in a particular field reviews and evaluates papers published in the journal. In the article, Professor Kim reviewed a paper written by Jang-Kun Song et al. and highlighted important research outcomes such as the efficient electric field switching of graphene oxide (GO) liquid-crystals in low-concentration dispersions and the demonstration of a prototype of a GO liquid-crystal display. This technology could lead the development of a flexible display. Professor Kim is an eminent scholar who has reported for the first time in the world on the solvent-based graphene oxide liquid crystals formation in 2011. For the article, please go to: http://www.kaist.ac.kr/_prog/download.php?filename=Nature_Materials_Professor_Sang-Ouk_Kim_Apr_2014.pdf
2014.03.26 View 11526
A research paper by Professor Myung-Chul Choi reviewed in Science (February 28, 2014) A research paper entitled “Transformation of taxol-stabilized microtubules into inverted tubulin tubules triggered by a tubulin conformation switch” was published in Nature Materials this year, dated January 19, 2014. Professor Myung-Chul Choi and Dr. Chae-Yeon Song from the Department of Bio and Brain Engineering at KAIST co-authored the paper together with researchers from the University of California in Santa Barbara and the Hebrew University of Jerusalem. Science, dated February 28, 2014, has recently reviewed the paper in its section called "Perspectives."
2014.03.13 View 10238
Professor Yong-Tak Im of Mechanical Engineering Appointed as President of Korea Institute of Machinery and Materials Yong-Tak Im, Professor of the Department of Mechanical Engineering at KAIST, was sworn in on February 25, 2014 as the 16th president of the Korea Institute of Machinery and Materials (KIMM), a leading government-funded research institution in Korea. KIMM was established in 1976 to contribute to the development of Korea through the invention of source technology and technology transfer in mechanical engineering. President Im graduated from Seoul National University, obtaining degrees of Bachelor of Science and Master’s in mechanical engineering. He later studied at the University of California in Berkeley and received a doctoral degree in mechanical engineering. After working as an assistant professor of the Industrial and Systems Engineering at the Ohio State University, President Im joined KAIST as a professor of mechanical engineering in 1989. President Im took many important posts at KAIST, including Dean of Planning Office, Dean of External Affairs and Public Relations Office, and Associate Vice President of Special Projects and Institutional Relations, making a great addition to the university’s endeavors for globalization. Among the awards President Im received was the William Johnson Award in 2007 presented by the Advances in Materials and Processing Technologies, the Research Achievement Award in 2010 by the Global Congress on Manufacturing and Management, and the Presidential Award in 2012 by the Republic of Korea. He was also elected as the vice president of the Korean Society of Mechanical Engineers, the largest association of professionals in the mechanical engineering field in Korea. President Im is currently a professor at POSCO, an internationally known Korean steel company, and a member of the Korean Academy of Science and Technology and the National Academy of Engineering of Korea, respectively. President Im will serve KIMM for three years until February 24, 2017.
2014.02.25 View 13568