nanomaterials
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Professor Sang Ouk Kim Receives the POSCO Academic Award
Professor Sang Ouk Kim of KAIST’s Department of Materials Science and Engineering received the 2015 POSCO Academic Award. The award ceremony took place at the annual conference of the Korean Institute of Metals and Materials on April 23, 2015.
The POSCO Academic Award has been presented to the Institute's researchers and academics in recognition of their contributions to the advancement of metals and materials engineering in Korea.
Professor Kim is known for his pioneering work in manipulating the properties (work function, conductivity, surface energy, chemo-responsiveness, etc.) of carbon-based materials using double-element doping. Through his research, Professor Kim showed that carbon materials could be extremely useful in various areas including solar batteries and flexible devices. His work has been recognized and published in such journals as Advanced Materials, which invited him to write a review paper on his research in its 25th anniversary issue in 2014, along with world-renowned scholars including the Nobel laureate Alan Heeger.
Professor Kim has published a total of 143 Science Citation Index papers in journals like Nature, Science, Nature Materials, Nature Communications, Advanced Materials, Nano Letters, and Physical Review Letters. According to Scopus, a bibliographic database containing abstracts and citations for academic journal articles, he has been cited 6,456 times and has the h-index of 44, an index describing the scientific productivity and impact of a researcher.
2015.04.22 View 9467 -
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 View 8717 -
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 9322 -
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 7453 -
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 8940 -
Core Technology for Lithium Air Secondary Battery Developed
KAIST-Kyonggi University joint research team developed composite catalyst out of nano fiber and graphene
Five times improvement in capacity compared to lithium-ion secondary battery, driving 800 km at maximum
The core technology for lithium air secondary battery, the next generation high capacity battery, has been developed.
A research team formed by KAIST Department of Materials Science’s Professors Il-Doo Kim and Seokwoo Jeon, and Kyonggi University Department of Materials Science’s Professor Yong-Joon Park has created a lithium air secondary battery, with five times greater storage than the lithium-ion secondary battery, by developing a nano fiber-graphene composite catalyst. The research results are published in the August 8th online edition of Nano Letters.
A cathode of a lithium-ion battery consists of graphite and an anode of the battery consists of a lithium transition metal oxide. Lithium-ion batteries are widely used in mobile phones and laptops. However, lithium-ion batteries cannot support electric vehicles, providing energy for only 160 kilometers on one full charge. The lithium air secondary battery just developed by the research team uses lithium on the cathode and oxygen on the anode. It is earning a popular acknowledgement among the next generation secondary battery research community for having lightweight mass and high energy density.
However, lithium-ion batteries remain difficult to commercialize because of their short lifespan. Lithium and oxygen meet up to form lithium oxide (Li2O2) at discharge, and decompose again at charge. In a traditional lithium air battery, this cycle does not occur smoothly and results in high resistance, thereby reducing the lifespan of the battery. It is thus essential to develop high efficiency catalyst that facilitates the formation and decomposition of lithium oxides.
The research team used electric radiation to develop a nano composite catalyst by mixing cobalt oxide nano fiber and graphene. The performance of the battery has been maximized by settling nonoxidative graphene, which has high specific surface area and electrical conductivity, on catalyst active cobalt oxide nano fiber. Applying the nano composite catalyst on both poles of the lithium air battery resulted in an improved lifespan of over 80 recharge cycles with capacity greater than 100mAh/g, five times greater than a lithium ion battery. The newly discovered charge-discharge property is the highest among the reported performances of the lithium air battery so far.
The lithium air battery is cheap to make, as the main materials are metal oxide and graphene. “There are yet more issues to resolve such as stability, but we will collaborate with other organizations to open up the era of electronic vehicles,” said Professor Il-Doo Kim. “We hope to contribute to vitalizing the fields of next generation lithium air battery by leading nanocatalyst synthesis technology, one of the core materials in the fields of secondary battery,” Professor Kim spoke of his aspiration.
The graduate students participated in the research are Won-Hee Ryu, a postdoctorate at KAIST Department of Materials Science, Sungho Song, a PhD candidate at KAIST Department of Materials Science, and Taek-Han Yoon, a graduate student at Kyonggi University.
Picture I: Schematic Diagram of Lithium Air Battery Made of Nano Composite Catalysts
Picture II: Images of Cobalt Oxide Nano Fibers and Graphene Nano Composite Catalysts
Picture III: Images of Manufacturing Process of Cobalt Oxide Nano Fibers and Graphene Nano Composite Catalysts for Lithium Air Battery
2013.10.18 View 11023 -
Nanofiber sensor detects diabetes or lung cancer faster and easier
Metal-oxide nanofiber based chemiresistive gas sensors offer greater usability for portable real-time breath tests that can be available on smart phones or tablet PCs in the near future.
Daejeon, Republic of Korea, June 11, 2013 -- Today"s technological innovation enables smartphone users to diagnose serious diseases such as diabetes or lung cancer quickly and effectively by simply breathing into a small gadget, a nanofiber breathing sensor, mounted on the phones.
Il-Doo Kim, Associate Professor of Materials Science and Engineering Department at the Korea Advanced Institute of Science and Technology (KAIST), and his research team have recently published a cover paper entitled "Thin-Wall Assembled SnO2 Fibers Functionalized by Catalytic Pt Nanoparticles and their Superior Exhaled Breath-Sensing Properties for the Diagnosis of Diabetes," in an academic journal, Advanced Functional Materials (May 20th issue), on the development of a highly sensitive exhaled breath sensor by using hierarchical SnO2 fibers that are assembled from wrinkled thin SnO2 nanotubes.
In the paper, the research team presented a morphological evolution of SnO2 fibers, called micro phase-separations, which takes place between polymers and other dissolved solutes when varying the flow rate of an electrospinning solution feed and applying a subsequent heat treatment afterward.
The morphological change results in nanofibers that are shaped like an open cylinder inside which thin-film SnO2 nanotubes are layered and then rolled up. A number of elongated pores ranging from 10 nanometers (nm) to 500 nm in length along the fiber direction were formed on the surface of the SnO2 fibers, allowing exhaled gas molecules to easily permeate the fibers. The inner and outer wall of SnO2 tubes is evenly coated with catalytic platinum (Pt) nanoparticles. According to the research team, highly porous SnO2 fibers, synthesized by eletrospinning at a high flow rate, showed five-fold higher acetone responses than that of the dense SnO2 nanofibers created under a low flow rate. The catalytic Pt coating shortened the fibers" gas response time dramatically as well.
The breath analysis for diabetes is largely based on an acetone breath test because acetone is one of the specific volatile organic compounds (VOC) produced in the human body to signal the onset of particular diseases. In other words, they are biomarkers to predict certain diseases such as acetone for diabetes, toluene for lung cancer, and ammonia for kidney malfunction. Breath analysis for medical evaluation has attracted much attention because it is less intrusive than conventional medical examination, as well as fast and convenient, and environmentally friendly, leaving almost no biohazard wastes.
Various gas-sensing techniques have been adopted to analyze VOCs including gas chromatography-mass spectroscopy (GC-MS), but these techniques are difficult to incorporate into portable real-time gas sensors because the testing equipment is bulky and expensive, and their operation is more complex. Metal-oxide based chemiresistive gas sensors, however, offer greater usability for portable real-time breath sensors.
Il-Doo Kim said, "Catalyst-loaded metal oxide nanofibers synthesized by electrospinning have a great potential for future exhaled breath sensor applications. From our research, we obtained the results that Pt-coated SnO2 fibers are able to identify promptly and accurately acetone or toluene even at very low concentration less than 100 parts per billion (ppb)."
The exhaled acetone level of diabetes patients exceeds 1.8 parts per million (ppm), which is two to six-fold higher than that (0.3-0.9 ppm) of healthy people. Therefore, a highly sensitive detection that responds to acetone below 1 ppm, in the presence of other exhaled gases as well as under the humid environment of human breath, is important for an accurate diagnosis of diabetes. In addition, Professor Kim said, "a trace concentration of toluene (30 ppb) in exhaled breath is regarded to be a distinctive early symptom of lung cancer, which we were able to detect with our prototype breath tester."
The research team has now been developing an array of breathing sensors using various catalysts and a number of semiconducting metal oxide fibers, which will offer patients a real-time easy diagnosis of diseases.
###
Youtube Link: http://www.youtube.com/watch?v=t_Hr11dRryg
For further inquires:
Il-Doo Kim, Professor of Materials Science and Engineering, KAIST
Advanced Nanomaterials and Energy Laboratory
Tel: +82-42-350-3329
Email: idkim@kaist.ac.kr
Clockwise from left to right: left upper shows a magnified SEM image of a broken thin-wall assembled SnO2 fiber. Left below is an array of breath sensors (Inset is an actual size of a breath sensor). The right is the cover of Advanced Functional Materials (May 20th issue) in which a research paper on the development of a highly sensitive exhaled breath sensor by using SnO2 fibers is published.
This is the microstructural evolution of SnO2 nanofibers as a function of flow rate during electrospinning.
2013.06.20 View 13400 -
Professor Sang-Ouk Kim Interviewed with Arirang TV on April 15, 2013
Professor Sang-Ouk Kim from the Department of Materials Science and Engineering made an appearance on April 15, 2013 at a morning show called “Korea Today” on Arirang TV, an English-language network based in Seoul, South Korea.
Professor Kim introduced his research on the development of flexible semiconductor technology. If commercialized, Professor Kim added, the technology would expedite the common use of wearable computers including mobile devices as well as the development of bio-medical implanted and wireless telemetry bio-devices. To play the video, please click the link below (00:25:00): http://www.arirang.co.kr/Player/TV_Vod.asp?HL=X&code=VOD&vSeq=68872
2013.04.30 View 8471 -
Ultra Elastic Electrode Material Developed
KAIST research team succeeded in developing the next generation flexible and elastic electrode material crucial in the development of flexible displays, wearable computers, and etc.
Professor Jeon Seok Woo’s team of the department of Materials Science and Engineering succeeded in the development of a super elastic material.
The result of the experiment was introduced as the research highlight in Nature Communications and is especially significant as the main driving force behind the achievement were domestic researchers.
Professor Jeons team developed a structured three dimensional nano-porous structure over a 1inch by 1inch area that is 10micrometers in thickness. The structure is fabricated using world’s largest area three dimensional nano patterning technique.
The nano-porous structure was injected with elastomeric material and was subsequently removed to yield an inverse three dimensional elastic nano material. The pores were infiltrated with liquid conductive material which yielded a super elastic flexible electrode.
The fabricated electrode showed amazing elasticity levels and was able to light LED lamps in a 200% stretched state without decrease in electrical conductivity.
Conventional methods included folding and expanding a material like an accordion or creating a mesh-like structure by making holes in the material. However these methods yielded materials with limited elasticity and even 100% stretching resulted in the drastic decrease in electrical conductivity.
Professor Jeon expects the domestically developed technology to obtain the upper hand in the market and make great contributions in both science and society.
2012.07.26 View 8952
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Ten Breakthroughs of the Year 2011 by Science
Porous Zeolite Crytals
Science, an internationally renowned scientific journal based in the US, has recently released a special issue of “Breakthrough of the Year, 2011,” dated December 23, 2011. In the issue, the journal introduces ten most important research breakthroughs made this year, and Professor Ryong Ryoo, Department of Chemistry at KAIST, was one of the scientists behind such notable advancements in 2011. Professor Ryoo has been highly regarded internationally for his research on the development of synthetic version of zeolites, a family of porous minerals that is widely used for products such as laundry detergents, cat litters, etc. Below is the article from Science, stating the zeolite research:
For Science’s “Breakthrough of the Year, 2011”, please go to:
http://www.sciencemag.org/site/special/btoy2011/
[Excerpt from the December 23, 2011 Issue of Science]
Industrial Molecules, Tailor-Made
If you ever doubt that chemistry is still a creative endeavor, just look at zeolites. This family of porous minerals was first discovered in 1756. They"re formed from different arrangements of aluminum, silicon, and oxygen atoms that crystallize into holey structures pocked with a perfect arrangement of pores. Over the past 250 years, 40 natural zeolites have been discovered, and chemists have chipped in roughly 150 more synthetic versions.
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Porous zeolite crystals are widely used as filters and catalysts. This year, researchers found new ways to tailor the size of their pores and create thinner, cheaper membranes.
CREDIT: K. VAROON ET AL., SCIENCE334, 6052 (7 OCTOBER 2001)
This abundance isn"t just for show. Three million tons of zeolites are produced every year for use in laundry detergents, cat litter, and many other products. But zeolites really strut their stuff in two uses: as catalysts and molecular sieves. Oil refineries use zeolite catalysts to break down long hydrocarbon chains in oil into the shorter, volatile hydrocarbons in gasoline. And the minerals" small, regularly arranged pores make them ideal filters for purifying everything from the air on spaceships to the contaminated water around the nuclear reactors destroyed earlier this year in Fukushima, Japan.
Zeolites have their limitations, though. Their pores are almost universally tiny, making it tough to use them as catalysts for large molecules. And they"re difficult to form into ultrathin membranes, which researchers would like to do to enable cheaper separations. But progress by numerous teams on zeolite synthesis this year gave this “mature” area of chemistry new life.
Researchers in South Korea crafted a family of zeolites in which the usual network of small pores is surrounded by walls holed with larger voids. That combination of large and small pores should lead to catalysts for numerous large organic molecules.
Labs in Spain and China produced related large- and small-pore zeolites by using a combination of inorganic and organic materials to guide the structures as they formed.
Meanwhile, researchers in France and Germany discovered that, by carefully controlling growth conditions, they could form a large-pore zeolite without the need for the expensive organic compounds typically used to guide their architecture as they grow. The advance opens the way for cheaper catalysts. In yet another lab, researchers in Minnesota came up with a new route for making ultrathin zeolite membranes, which are likely to be useful as a wide variety of chemically selective filters.
This surge of molecular wizardry provides a vivid reminder that the creativity of chemists keeps their field ever young.
Related References and Web Sites
2011.12.23 View 11389 -
From Pencil Lead to Batteries: the Unlimited Transformation of Carbon
Those materials, like lead or diamond, made completely up of Carbon are being used in numerous ways as materials or parts. Especially with the discovery of carbon nanotubes, graphemes, and other carbon based materials in nanoscale, the carbon based materials are receiving a lot of interest in both fields of research and industry.
The carbon nanotubes and graphemes are considered as the ‘dream material’ and have a structure of a cross section of a bee hive. Such structure allows the material to have strength higher than that of a diamond and still be able to bend, be transparent and also conduct electricity. However the problem up till now was that these carbon structures appeared in layers and in bunches and were therefore hard to separate to individual layers or tubes.
Professor Kim Sang Wook’s research team developed the technology that can assemble the grapheme and carbon nanotubes in a three dimensional manner.
The team was able to assemble the grapheme ad carbon nanotubes in an entirely new three dimensional structure. In addition, the team was able to efficiently extract single layered grapheme from cheap pencil lead.
Professor Kim is scheduled to give a guest lecture in the “Materials Research Society” in San Francisco and the paper was published in ‘Advanced Functional Materials’ magazine as an ‘Invited Feature Article’.
2011.05.11 View 10162
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Dong Ah Newspaper Publish '100 Koreans who will Represent Korea in 10 years'
The 2011 list of ‘100 Koreans who will Represent Korea in 10 years’ published by Dong Ah Newspaper includes people of varying ages, vocation, and gender.
In terms of University Professors, five professors from each of KAIST and SNU (Seoul National University) were selected. Especially Professor Charles Ahn received the most votes due to his world class talent, potential, and dedication.
Professor Kim Sang Wook of the Department of Materials Science and Engineering is the world leading expert in the field of ‘Atom Construction Nanotechnology’ which deals with using macromolecules, carbon nanotubes, and grapheme to form various structures. His work on ‘low cost, large area nano patterning technology’ is expected to overcome the limits of nano treatment processes and its application in semi-conductors or displays carries great promise.
Professor Kim Eun Sung of the Department of Physics discovered a new quantum behavior, supersolidity, in a low temperature, solid Helium for the first time in the world and is the leading scientist that leads the mechanics behind such a phenomenon. Professor Kim is leading the field of supersolidity through his works on hidden phase in a low temperature solid Helium, the understanding the role of crystalline faults in the supersolidity phenomenon, and the destruction of the supersolid’s macromolecular phenomenon through spinning solids.
Professor Charles Ahn of the Graduate School of Innovation and Technology Management has been working as the developer of the V3 series (an anti-computer virus Vaccine Program) since 1988. He established the ‘Charles Ahn Research Center’ in 1995 and his solid and practical management style won him rave reviews. Professor Ahn was appointed as the Professor of the Graduate School of Innovation and Technology Management and has been teaching entrepreneurial perspective and Technology Management.
Professor Lee Sang Yeop of the Department of Biology and Chemical Engineering developed world’s most efficient production method of succinic acid, developed high efficiency, tailored, culture for the production of key amino acids, Valine and Threonine, developed the production culture off bio-buthanol which is superior to bio-ethanol, and is widely known as one of the leaders in the field of metabolic engineering.
Professor Jeong Ha Woong of the Department of Physics is being regarded as world leader in the field of Complex System Network Sciences. He implemented Statistical Physics to Complex Systems and also used the concept of ‘Networks’ and published 80 papers, including 5 which were published in Nature Magazine.
2011.04.30 View 12514