materials
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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 9303 -
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 7442 -
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 13558 -
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 11326 -
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 8075 -
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 8927 -
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 8182 -
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 9348 -
A Molecular Switch Controlling Self-Assembly of Protein Nanotubes Discovered
International collaborative research among South Korea, United States, and Israel research institutionsThe key to the treatment of cancer and brain disease mechanism The molecular switch that controls the self-assembly structure of the protein nanotubes, which plays crucial role in cell division and intracellular transport of materials, has been discovered. KAIST Bio and Brain Engineering Department’s Professor Myeong-Cheol Choi and Professor Chae-Yeon Song conducted the research, in collaboration with the University of California in Santa Barbara, U.S., and Hebrew University in Israel. The findings of the research were published in Nature Materials on the 19th. Microtubules are tube shaped and composed of protein that plays a key role in cell division, cytoskeleton, and intercellular material transport and is only 25nm in diameter (1/100,000 thickness of a human hair). Conventionally, cancer treatment focused on disrupting the formation of microtubules to suppress the division of cancer cells. In addition Alzheimer’s is known to be caused by the diminishing of structural integrity of microtubules responsible for intercellular material transport which leads to failure in signal transfer. The research team utilized synchrotron x-ray scattering and transmission electron microscope to analyze the self assemble structure of protein nanotubes to subnanometer accuracy. As a result, the microtubules were found to assemble into 25nm thickness tubules by stacking protein blocks 4 x 5 x 8nm in dimension. In the process, the research team discovered the molecular switch that controls the shape of these protein blocks. In addition the research team was successful in creating a new protein tube structure. Professor Choi commented that they were successful in introducing a new paradigm that suggests the possibility of controlling the complex biological functions of human’s biological system with the simple use of physical principles. He commented further that it is anticipated that the findings will allow for the application of bio nanotubes in engineering and that this is a small step in finding the mechanism behind cancer treatment and neural diseases.
2014.02.03 View 9779 -
Rechargeable Lithium Sulfur Battery for Greater Battery Capacity
Professor Do Kyung Kim from the Department of Material Science and Engineering and Professor Jang Wook Choi from the Graduate School of EEWS have been featured in the lead story of the renowned nanoscience journal Advanced Materials for their research on the lithium sulfur battery. This new type of battery developed by Professor Kim is expected to have a longer life battery life and [higher] energy density than currently commercial batteries.
With ample energy density up to 2100Wh/kg—almost 5.4 times that of lithium ion batteries—lithium sulfur batteries can withstand the sharp decrease in energy capacity resulting from charging and discharging—which has been considered the inherent limitation of the conventional batteries.
Professor Kim and his research team used one-dimensional, vertical alignment of 75nm tick, 15μm long sulfur nanowires to maximize electric conductivity. Then, to prevent loss of battery life, they carbon-coated each nanowire and prohibited direct contact between the sulfur and electrolyte.
The result was one of the most powerful batteries in terms of both energy performance and density. Compared to conventional batteries which suffer from continuous decrease in energy capacity after being discharged, the lithium sulfur battery maintained 99.2% of its initial capacity after being charged and discharged 300 times and up to 70% even after 1000 times.
Professor Kim claims that his new battery is an important step forward towards a high-performance rechargeable battery which is a vital technology for unmanned vehicles, electric automobiles and energy storage. He hopes that his research can solve the problems of battery-capacity loss and contribute to South Korea’s leading position in battery technology. Professor Kim’s research team has filed applications for one domestic and international patent for their research.
2013.12.11 View 11042 -
Graduate Student at KAIST Awarded Best Prize at the 9th Inside Edge
Sun-Jin Choi, a Ph. D. candidate in the Department of Materials Science and Engineering at KAIST, under the guidance of Professor Il-Doo Kim, won the best prize at the 9th Inside Edge Contest hosted by Samsung Electro-Mechanics.
Choi was awarded prize money totaling fifteen million won at the award ceremony held on November 22 at the Mirae Hall at the headquarters of Samsung Electro-Mechanics in Suwon.
Choi’s research, titled “Exhaled Breath Sensor Arrays for the Non-invasive and Real-time Diagnosis of Diabetes by Detection of Acetone,” was recognized for its creativity and uniqueness.The Inside Edge is an international thesis competition which was started in 2005 to encourage and support creative research and potential technological development among young scientists and engineers.
Sun-Jin Choi (left) and Professor Il-Doo Kim (right).
2013.12.11 View 8682 -
First International Conference on Science and Technology for Society
KAIST co-organized the 2013 International Conference on Science and Technology for Society which was held on November 28 at the Grace Hall in Seoul EL-Tower. More than 300 people, including members of the Global Social Technology Advisory Board, domestic social technology experts, private companies, government officials, private citizens, and students joined the conference to discuss the roles and responsibilities of science and technology for society.
R&D policies and technologies for solving social issues were introduced, and discussions were held on desirable directions for technological development.
The first speaker, Yasushi Watanabe, Director of RISTEX (Research Institute of Science and Technology for Society) in Japan, introduced the importance of science and technology for society under the title “Change of R&D Paradigm for Society.”
Robert Wimmer, GrAT (Center for Appropriate Technology), Vienna University of Technology in Austria, presented “Need-oriented Design & Solutions for Development.” Kiyoaki Murakami, MRI, Japan, presented “Introduction of Platinum Vision” and Robert Ries, University of Florida, U.S.A., presented “Evaluating the Social Impacts of the Built Environment Using Life Cycle Assessment.”
Case studies on social enterprises and presentations on R&D for solving social problems were introduced by ICISTS (International Conference for the Integration of Science, Technology and Society), which is a student group at KAIST, National Research Foundation of Korea (NRF), Korea Institute of Machinery and Materials (KIMM), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Korea Institute of Industrial Technology (KITECH), Electronics and Telecommunication Research Institute (ETRI), and Korea Research Institute of Chemical Technology (KRICT).The conference was hosted by the Ministry of Science, ICT, and Future Planning and co-organized by NRF, KIMM, KRIBB, KITECH, ETRI and KRICT.
2013.12.11 View 10076