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Press Release on Piezoelectric Nanogenerators of ZnO with Aluminium Nitride Stacked Layers by the American Institute of Physics
The American Institute of Physics (AIP) released a news article entitled “Zinc Oxide Materials Tapped for Tiny Energy Harvesting Devices” on January 13, 2015. The article described the research led by Professor Giwan Yoon of the Electrical Engineering Department at KAIST. It was published in the January 12, 2015 issue of Applied Physics Letters. AIP publishes the journal. For the news release, please visit the link below: The American Institute of Physics, January 13, 2015 “Zinc Oxide Materials Tapped for Tiny Energy Harvesting Devices” New research helps pave the way toward highly energy-efficient zinc oxide-based micro energy harvesting devices with applications in portable communications, healthcare and environmental monitoring, and more http://www.aip.org/publishing/journal-highlights/zinc-oxide-materials-tapped-tiny-energy-harvesting-devices
2015.02.04
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KAIST Researchers Fabricate Defect-free Graphene for Lithium-ion Batteries
Although graphene has been hailed as promising materials for lithium-ion batteries, making it for large-scale production has remained a challenging task for researchers. So far, high-quality graphene has been produced at the expense of large volume. It is possible to fabricate bulk quantities of graphene, but they will likely contain many defects. Recently, a KAIST research team, headed by Professors Jung-Ki Park and Hee-Tak Kim from the Department of Chemical and Biomolecular Engineering, developed a fabrication method to produce a large amount of defect-free graphene (df-G) while preserving the structural integrity of the graphene. This research result was published online in the July 11, 2014 issue of Nano Letters, entitled "Defect-free, Size-tunable Graphene for High-performance Lithium Ion Battery." Phys.org, a science, research and technology news website, published an article on this research. To read article, please visit the link below: Phys.org, August 22, 2014 “Scientists fabricate defect-free graphene, set record reversible capacity for Co3O4 node in Li-ion batteries” http://phys.org/news/2014-08-scientists-fabricate-defect-free-graphene-reversible.html
2014.09.07
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Newsweek: The Goosebump Sensor That Knows How You Feel
Newsweek covered the introduction of the goosebump sensor invented by Professor Young-Ho Cho of the Department of Bio and Brain Engineering at KAIST in an article dated July 27, 2014. The article entitled “The Goosebump Sensor That Knows How You Feel” explains how the sensor works and reports on the current research and development trends in emotion-sensing technology. Professor Cho’s research paper was originally published in the journal Applied Physics Letters on June 24, 2014, titled “A Flexible Skin Piloerection Monitoring Sensor." Newsweek, July 27, 2014 “The Goosebump Sensor That Knows How You Feel” http://www.newsweek.com/goosebump-sensor-knows-how-you-feel-260689
2014.07.28
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Professor Sang Ouk Kim receives the 2014 Prime Minister Award for Nano Research
Professor Sang Ouk Kim Sang Ouk Kim, a professor of Materials Science and Engineering at KAIST, received the 2014 Prime Minister Award from the Korean government for his nano research. The award ceremony, Nano Korea 2014, was held on July 2, 2014 at Coex in Seoul, Korea. Professor Kim was recognized for his research on the control of various shapes of ultra-fine nano-structures using molecular assembly with ductile materials, such as polymers and carbon nano materials, and for his contribution to the growth of the nano field in Korea. He developed a new molecular assembly control technology, for the first time in the world, which produced large-scale, ultra-fine nanopatterns through controlling the molecular arrangement of block copolymers. Using this technology, he further created a new semiconductor nanotechnology to reinforce the existing lithographic process of semiconductor manufacturing. In addition, Professor Kim has focused on making a new type of three-dimensional carbon nano-materials by assembling carbon nanotubes or graphene at the molecular level. Developing a new process to produce nano-materials through the chemical doping process of carbon materials, which can be widely applied to solar cells or energy devices, is one of his research interests as well. Professor Kim has published a total of 124 papers in international journals, such as Nature, Science, Nature Materials, Nature Communications, Advanced Materials, and Nano Letters. He was recently invited by Advanced Materials to contribute a review article for its 25th anniversary issue. Professor Kim received both the KAIST Academic Award and the 13th Young Scientist Award of Korea in 2010. Since March 2014, he has served as one of the chair professors of KAIST. Most recently, he was selected as the Scientist of the Month in June 2014 by the Ministry of Science, ICT and Future Planning, Republic of Korea, and the National Research Foundation of Korea.
2014.07.08
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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 8064
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 6708
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 9770
Thermoelectric generator on glass fabric for wearable electronic devices
Wearable computers or devices have been hailed as the next generation of mobile electronic gadgets, from smart watches to smart glasses to smart pacemakers. For electronics to be worn by a user, they must be light, flexible, and equipped with a power source, which could be a portable, long-lasting battery or no battery at all but a generator. How to supply power in a stable and reliable manner is one of the most critical issues to commercialize wearable devices. A team of KAIST researchers headed by Byung Jin Cho, a professor of electrical engineering, proposed a solution to this problem by developing a glass fabric-based thermoelectric (TE) generator that is extremely light and flexible and produces electricity from the heat of the human body. In fact, it is so flexible that the allowable bending radius of the generator is as low as 20 mm. There are no changes in performance even if the generator bends upward and downward for up to 120 cycles. To date, two types of TE generators have been developed based either on organic or inorganic materials. The organic-based TE generators use polymers that are highly flexible and compatible with human skin, ideal for wearable electronics. The polymers, however, have a low power output. Inorganic-based TE generators produce a high electrical energy, but they are heavy, rigid, and bulky. Professor Cho came up with a new concept and design technique to build a flexible TE generator that minimizes thermal energy loss but maximizes power output. His team synthesized liquid-like pastes of n-type (Bi2Te3) and p-type (Sb2Te3) TE materials and printed them onto a glass fabric by applying a screen printing technique. The pastes permeated through the meshes of the fabric and formed films of TE materials in a range of thickness of several hundreds of microns. As a result, hundreds of TE material dots (in combination of n and p types) were printed and well arranged on a specific area of the glass fabric. Professor Cho explained that his TE generator has a self-sustaining structure, eliminating thick external substrates (usually made of ceramic or alumina) that hold inorganic TE materials. These substrates have taken away a great portion of thermal energy, a serious setback which causes low output power. He also commented, "For our case, the glass fabric itself serves as the upper and lower substrates of a TE generator, keeping the inorganic TE materials in between. This is quite a revolutionary approach to design a generator. In so doing, we were able to significantly reduce the weight of our generator (~0.13g/cm2), which is an essential element for wearable electronics." When using KAIST's TE generator (with a size of 10 cm x 10 cm) for a wearable wristband device, it will produce around 40 mW electric power based on the temperature difference of 31 °F between human skin and the surrounding air. Professor Cho further described about the merits of the new generator: "Our technology presents an easy and simple way of fabricating an extremely flexible, light, and high-performance TE generator. We expect that this technology will find further applications in scale-up systems such as automobiles, factories, aircrafts, and vessels where we see abundant thermal energy being wasted." This research result was published online in the March 14th issue of Energy & Environmental Science and was entitled "Wearable Thermoelectric Generator Fabricated on Glass Fabric." Youtube Link: http://www.youtube.com/watch?v=BlN9lvEzCuw&feature=youtu.be [Picture Captions] Caption 1: The picture shows a high-performance wearable thermoelectric generator that is extremely flexible and light. Caption 2: A thermoelectric generator developed as a wristband. The generator can be easily curved along with the shape of human body. Caption 3: KAIST’s thermoelectric generator can be bent as many as 120 times, but it still shows the same high performance.
2014.04.21
View 18737
An Electron Cloud Distribution Observed by the Scanning Seebeck Microscope
All matters are made of small particles, namely atoms. An atom is composed of a heavy nucleus and cloud-like, extremely light electrons. Korean researchers developed an electron microscopy technique that enables the accurate observation of an electron cloud distribution at room-temperature. The achievement is comparable to the invention of the quantum tunneling microscopy technique developed 33 years ago. Professor Yong-Hyun Kim of the Graduate School of Nanoscience and Technology at KAIST and Dr. Ho-Gi Yeo of the Korea Research Institute of Standards and Science (KRISS) developed the Scanning Seebeck Microscope (SSM). The SSM renders clear images of atoms, as well as an electron cloud distribution. This was achieved by creating a voltage difference via a temperature gradient. The development was introduced in the online edition of Physical Review Letters (April 2014), a prestigious journal published by the American Institute of Physics. The SSM is expected to be economically competitive as it gives high resolution images at an atomic scale even for graphene and semiconductors, both at room temperature. In addition, if the SSM is applied to thermoelectric material research, it will contribute to the development of high-efficiency thermoelectric materials. Through numerous hypotheses and experiments, scientists now believe that there exists an electron cloud surrounding a nucleus. IBM's Scanning Tunneling Microscope (STM) was the first to observe the electron cloud and has remained as the only technique to this day. The developers of IBM microscope, Dr. Gerd Binnig and Dr. Heinrich Rohrer, were awarded the 1986 Nobel Prize in Physics. There still remains a downside to the STM technique, however: it required high precision and extreme low temperature and vibration. The application of voltage also affects the electron cloud, resulting in a distorted image. The KAIST research team adopted a different approach by using the Seebeck effect which refers to the voltage generation due to a temperature gradient between two materials. The team placed an observation sample (graphene) at room temperature (37~57℃) and detected its voltage generation. This technique made it possible to observe an electron cloud at room temperature. Furthermore, the research team investigated the theoretical quantum mechanics behind the electron cloud using the observation gained through the Seebeck effect and also obtained by simulation capability to analyze the experimental results. The research was a joint research project between KAIST Professor Yong-Hyun Kim and KRISS researcher Dr. Ho-Gi Yeo. Eui-Seop Lee, a Ph.D. candidate of KAIST, and KRISS researcher Dr. Sang-Hui Cho also participated. The Ministry of Science, ICT, and Future Planning, the Global Frontier Initiative, and the Disruptive Convergent Technology Development Initiative funded the project in Korea. Picture 1: Schematic Diagram of the Scanning Seebeck Microscope (SSM) Picture 2: Electron cloud distribution observed by SSM at room temperature Picture 3: Professor Yong-Hyun Kim
2014.04.04
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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 7929
Extreme Tech: Nanowire "impossible to replicate" fingerprints could eliminate fraud, counterfeit goods
Research done by Professor Hyun-Joon Song of Chemistry at KAIST on anti-counterfeit, nanoscale fingerprints generated by randomly distributed nanowires was introduced by Extreme Tech, an online global science and technology news. For the articles, please go to: Extreme Tech, March 25, 2014Nanowire ‘impossible to replicate’ fingerprints could eliminate fraud, counterfeit goods http://www.extremetech.com/extreme/179131-nanowire-impossible-to-replicate-fingerprints-could-eliminate-fraud-counterfeit-goods
2014.03.26
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Professor Kyung-Wook Paik Receives the Best Presentation Award from 2014 Pan Pacific Symposium
The Surface Mount Technology Association (SMTA) hosted its 19th Annual Pan Pacific Microelectronics Symposium on February 11-13, 2014 in Hawaii. The 2014 conference, promoting international technical exchange and extensive networking among microelectronics professionals from around the world, presented over 50 papers from 17 countries. Professor Kyung-Wook Paik of Materials Science Engineering at KAIST received the Best Presentation Award for his paper titled, “Novel Nanofiber Anisotropic Films for Nine Pitch Assembly” at the conference. SMTA is an international network of professionals in electronics assembly technologies, including Microsystems, emerging technologies, and related business operations.
2014.03.17
View 7268
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