Biography: Chris G Whiteley is Emeritus Professor Biochemistry at Rhodes University, South Africa and Distinguished Research Professor at National Taiwan University & Technology.
The fight against infectious diseases can be manifested by consideringdifferences in structure between specific biomedical targets (enzymes) in the human host and the parasite. The interaction of silver nanoparticles (AgNP) with triosephosphateisomerase (TIM) is modelled using a molecular dynamics simulation computer programme. The simulation of the ‘docking’, first as a rigid-body docked complex, and eventually through flexible-fit analysis, creates ten different enzyme-nanoparticle complexes. The rigid-body docked complex is conformationally flexible to accommodate the AgNP that orientates itself within the ‘docking’ site until a more stable structure is formed at convergence. Normalisation of the data obtained from changes to interactive binding energy profiles, rmsd, B-factors, dihedral angles [phi, Δφ; psi, Δψ; chi, Δχ], volume occupied by Cα [ΔVcα], secondary structural elements (α-helix, β-strand, random coil), number of contact residues, their hydrophobicities, solvent accessible surface area and surface electrostatic potentials of each of these AgNP-TIM complexes is computed. Summation of these data narrows the selection to one or two final probable AgNP-TIM structures. Silver nanoparticles (60 nM; 2– 4 nm diameter) selectively inhibited recombinant triosephosphateisomerase from Plasmodium falciparum (PfTIM) with a 7-fold decrease in enzyme catalytic efficiency over the human enzyme (hTIM). These enzymes were expressed, purified and characterised. High specific activity (1207 U.mg-1) with a fold purification of ~1.8 and a yield of 48 % were (hTIM) after gel filtration while, in contrast, PfTIM afforded a specific activity of 1387 U.mg-1 with a fold purification of ~6.8 and a yield of 57 %.PfTIM had an optimal pH and temperature, Km and Vmax of 5.25, 25 °C, 12.8 mM and 1.13 μmol.ml-1 min respectively while for hTIM the pH and temperature optima, Km and Vmax were 6.75, 30 °C; 8.2 mM and 1.35 μmol.ml-1min-1. Respective Ki values were 283 nM [hTIM] and 85.7 nM [PfTIM]. Key structural differences between the two enzyme variants, especially with Cys13 at the dimer interface of PfTIM, were significant to suggest unique characteristics allowing for selective targeting of PfTIM by AgNPs.
Biography: Dr Hanfang Hao is the electron microscopy application specialist in ZEISS APAC group. She received her B.Eng. degree and PhD degree in Electrical and Computer Engineering from the National University of Singapore. She has been working on the various FIB-SEM and SEMs since 2009. Her doctoral research was focusing on plasmonic nanostructure direct-patterning using focused ion beams. Prior to joining Zeiss, she was working as a research scientist working on Dielectric Nano-antennas at Data storage Institute, A*STAR in Singapore.
Abstract: The E-mobility megatrend has dramatically increased the demand for high energy storage and large capacity Lithium-ion batteries (LIB), sparking several research interests globally. In addition to higher capacity, safety is equally important for long-term operation and stability, which requires thorough understanding of battery materials and structural properties.
LIB is a complicated system which includes features from cm to nm level. Multiscale microscopic characterization of LIB materials and cells based on X-ray microscopy (XRM) systems and scanning electron microscopy (SEM) explore the insides of the LIB with regards to by-products spreading, surface electrolyte interface (SEI) information, dendrite growth and structural changes, which are key for battery performance. XRM technique is non-destructive and can provide 3D information of the battery’s native state at sub µm scale without the need to cut it open. The same sample can be further studied with SEM at nanometer scale. Combining SEM and XRM has transformed existing workflows and enabled precise targeting of features of interest. Combination of in-situ Raman spectroscopy, EDS and surface resistivity measurement using EBAC inside a SEM provides complimentary sets of information, which help to map the spatial distribution various elements/components in lithium ion batteries and reveal changes in the concentration and composition at different stages of charge cycling. These capabilities enable detailed understanding how the product is operating under the intended service conditions and develop advanced materials to improve the performance of LIBs.
Nanocomposites / Bionanocomposites Materials
Biography: Walter Kaminsky received his PhD degree in chemistry from the University of Hamburg in 1971. He was a professor for Technical and Macromolecular Chemistry at the University of Hamburg (1979-2008), is now retired and consults in the field of polyolefin nanocomposites, catalysis, and recycling of plastics and scrap tires by pyrolysis. His research focused on synthesis of polyolefin nanocomposites by a high active, soluble metallocene catalyst system and the development of a technical pyrolysis plant for getting valuable fractions from hydrocarbon containing waste.
He was President of the German Chemical Society GDCH, Hamburg section, Dean of the Chemical Faculty of Hamburg University, Director of the Institute for Technical and Macromolecular Chemistry, and published more than 400 papers/books and holds 30 patents. He has received many awards and honors such as the European Research Prize, the Carothers Award (USA), the Walter Ahlström Prize of the Finnish Academies of Technology, the Benjamin Franklin Medal (USA), and the Hermann-Staudinger prize and is Honour Doctor of the Aalto University, Finland and Honour Professor of the East China and Zhejiang Universities.
Abstract: In the last years, much research in academic and industrial laboratories has focused on poly-olefin nanocomposites because of their high potential as materials with novel properties. Exceptionally strong polyolefin nanocomposites can be synthesized by in-situ polymerization with metallocene catalysts. The metallocene/methylaluminoxane catalyst, soluble in hydrocarbons, is absorbed on the surface of the nanofiller, then by addition of ethene or propene, a polyolefin film is formed, covering the nanoparticles, layered silicates, or fibers. Polyolefin nanocomposites produced by in-situ generation show better mechanical properties than material produced by mechanical blending. Monospheres (balls of silica, diameter 200-250 nm), carbon fibers (diameter 200 nm, length 0.5-3 mm), and multi-walled carbon nanotubes (diameter 15-25 nm, length 50 µm) were used as fillers. Before polymerization, the fillers were separated by ultra sound and then treated by the catalyst. The thickness of the polyolefins on the surface can be controlled by the pressure of ethene or propene and by the polymerization time. By this method, highly filled polypropylene nanocomposites can be obtained with a silica content of up to 85 wt%. Such combined materials are stiff and hard. Every particle is sur-rounded by a thin film of polyolefin with a thickness of 30 to 100 nm. Carbon fibers and carbon nanotubes are covered with isotactic or syndiotactic polypropylene. Because of the hy-drophobic character of the carbon surface, the polymer is drawing on the fiber. This leads to a reinforced combined polymer with special properties. The crystallization temperature is 10 °C higher and therefore the crystallization rate up to 20 times faster than that of pure syndiotactic polypropylene. The form stability increased by 100 % if 3 wt% of carbon nanotubes are in-corporated.
Dr. Ajit D. Kelkar is a Professor and Chair of Nanoengineering Department at Joint School of Nanoscience and Nanoengineering. He also serves as an Interim Director for the Center of Excellence in Advanced Manufacturing. For the past twenty-five years, he has been working in the area of polymeric and ceramic matrix composites. Presently he is involved in the development of nano engineered multifunctional materials for various aerospace applications including delamination resistant composites, radiation shielding materials, microvascular sections for damage monitoring etc. He has published over two hundred papers and has edited two books in the area of Nano Engineered materials. He is member of several professional societies including ASME, SAMPE, AIAA, ASM, and ASEE
Abstract: During the past decade use of both carbon and fiberglass composites have increased dramatically for aerospace applications. Advances in conventional tape laminates and textile composites provide aircraft manufacturers’ important technology, but the industry lacks the confidence to use these composites to manufacture primary load carrying structures due to low damage tolerance. One of the critical problems is failure due to delaminations of composite laminates via low velocity impact loadings and fatigue loadings. To alleviate this problem, several methods involving use of the nano technology, will be discussed. This talk will address various methods and material systems for processing and integration of the nano material constituents. This newly developed reinforced polymer nanocomposites and the processing methodologies have shown a promising means of improving the interlaminar properties of woven fiberglass composites compared to the traditional methods such as stitching and Z pinning to improve interlaminar properties of woven composites. In addition, talk will present latest innovations for fabrication and characterization of microvascular channels in polymeric composite materials, which are like to have variety of applications including real time damage monitoring in the aircraft composite skins with embedded sensors. Space Radiation has become one of the major factors in successful long duration space exploration. Exposure to space radiation not only can affect the health of astronauts but also can disrupt or damage materials and electronics. Hazards to materials include degradation of properties, such as, modulus, strength, or glass transition temperature. Electronics may experience single event effects, gate rupture, burnout of field effect transistors and noise. Talk will also cover development of novel resin system for multifunctional applications that require radiation protection for the long duration space missions.
Biography: He had research and development work in Thosiba Silicon Company after getting Master degree in graduate course of Gunma University. He had assistant work in Ashikaga Institute of Technology in 1980, continuously to be lecturer and assistant professor 2006, and associate professor 2007, and associate professor 2017 in Ashikaga University.
Abstract: There were great discussion and papers concerning with Molecular Parity Violation since from ‘Question of parity conservation in weak interactions’ by T. D. Lee, and C. N. Yang, Phys. Rev., 1956. It was followed that hydrogen atom must have optical activity by the chiral WNC (weak neutral current) between electron and proton (F.C Michel, 1965). It was impossible to realize because WNC was too law energy to detect it. Study had been done to amplify APV(atomic parity violation) energy employing heavy atom by Zel’ dovich (1966). R. A. Harris showed a very suggestable theory (1978) that the Hund’s Paradox (tunnel quantum effect) was combined with Quantum Vibration to amplify PVED (parity violence energy difference) resulting in molecular chiral vibrational stage to be appeared. STM (scanning tunnel Microscope) has already realized in physical field. In the context of above history, I was interested in Molecular Parity Violation of copper complex in chemistry field.
I designed a square pyramidal five coordinated asymmetric copper complex inspired from structures of phthalocynate-copper (II), hemocyanin and vitamin B12 etc. I synthesized Aqua[(6-carboxyl-2-pyridylamide)hisutaminato]copper (II) 1 and some related copper complexes. We have reported the crystal and molecular structure of 1 defined by X-ray crystallographic analysis (ANALYTICAL SCIENCE, 23, 37, 2007). The single crystal of 1 was racemic complex. The fifth apical H2O ligand of 1 is exchangeable to surrounding molecule such as solvent H2O, MeOH molecule in solution. The asymmetric tetradentate ligand of the basal plane gives planar-R or planar-S chirality to 1 depending on the coordination mode of the apical ligand to central copper atom. It is that the clock wise sense atom order of the basal plane seeing from the apical ligand gives planar-R chirality to 1. The counter clock wise sense atom order of the basal plane gives planar-S chirality to 1. At the same time, this designed asymmetric basal plane would give the chiral quantum vibration mode to the central copper atom because of R. A. Harris suggestion. The PVED of 1 was amplified to planar-R enantiomer priority side in this system. The planar-R enantiomer of 1 was assigned to [α]D + value in chemistry way which will be shown in the Conference. So that, each enantiomer has itself the diastereomeric effect of the chiral copper atom mode and visible chiral ligation mode of the fifth ligand. Racemic 1 gave the mutarotation phenomenon in polarimetry as chiral sign movements in aqueous methanol solution as shown in Figure 1. The [α]D data showed that it started from +2000° (not 0° is important) in planar-R enantiomer priority equilibrium to increase to +2500° and then to decrease crossing 0° resulted to -1240° in new planar-S enantiomer priority equilibrium reached. It is worthy that the very low polarimetry energy (~10-23J/molecule) was conjugated to PVED and moved the chiral equilibrium between planar-R and planar-S enantiomer of 1 resulted in giving us mutarotation phenomenon as an average intensity data. This data would be recorded as a part of MPV phenomenon of 1. It should be known that the MPV of 1 has exists always even if the detection has not been done in this system. Other relative copper complexes showed almost the same kind of phenomena in polarimetry. Hund’s Paradox and Harris suggestion would be conjugated in this system. The heavy door would be opened
Biography: C. Bor Fuh is a Prof. of Applied Chemistry at National Chi Nan University, Taiwan.
He received his PhD from University of Utah and worked as a postdoc research fellow at biomedical engineering department of Cleveland Clinic Foundation in USA. He was a guesting professor at Osaka University in Japan. His major fields of research interest include functional nanomaterials, functional nanoparticles, thin channel, magnetic immunoassay and related techniques for analytical and biochemical analyses.
Functional nanomaterials have become useful and popular in many technological applications for recent years. The advantages of functional nanomaterials have been exploited and extended in various applications for many years. This presentation would use various functional nanoparticles as examples to illustrate their advantages on applications of material science and biochemical technology. Several functional nanomaterials would be discussed. Biomarker detection using magnetic immunoassay in thin channels would be emphasized and demonstrated for applications. In comparison with other methods, this method has lower detection limit and wider linear range. This technique has great potential to provide a simple, fast, sensitive, and selective analysis for nanoparticles, proteins, and other biomaterials.
Biography: King-Chuen Lin is a Distinguished Professor at National Taiwan University. He received PhD from Michigan State University and postdoctoral career at Cornell University. His research interests are photodissociation and reaction dynamics, materials designed for sensors and catalysts, and single molecule spectroscopy. He received Academic Award of Ministry of Education, Taiwan, in 2014, and Richard B. Bernstein Award in International Conference on Stereodynamics-2018. He serves as an Associate Editor for J. Chin. Chem. Soc.(Taipei) and a member of Editorial Board for Scientific Reports. He has published 202 peer-reviewed papers and edited one book on reaction dynamics and chemical kinetics.
Abstract: Palladium nanoparticles (Pd NPs) immobilized on a garlic skin-derived activated carbons (GACs) was synthesized. The morphology, structure, surface compositions, and textural properties of the GACs and Pd@GAC catalyst were examined by a variety of physicochemical characterization techniques which revealed a dispersion of Pd NPs with average particle size of ca. 21 nm on sheet-like graphitized GACs. The Pd@GAC catalyst, which can be facilely prepared with biowaste feedstocks, exhibited excellent catalytic performances for efficient reduction of Cr(VI) with extraordinary stability and recyclability over at least five repeated catalytic test cycles. On the other hand, we report the synthesis, characterization, and catalytic application of ruthenium nanoparticles (Ru NPs) supported on plastic-derived carbons (PDCs) synthesized from plastic wastes (soft drink bottles) as an alternative carbon source. The catalytic activity of Ru@PDC for the reduction of potassium hexacyanoferrate(III), (K3[Fe(CN)6]), and new fuchsin (NF) dye by NaBH4 was performed under mild conditions.
Further, we present ultra-sensitive sensing of a prostate-specific antigen (PSA), which is used as a biomarker to detect prostate cancer, using a molybdenum series (MoO3, MoS2, and MoSe2) of two-dimensional nanosheets (2D NSs). The design of a 2D NS-based PSA aptamer sensor system was demonstrated based on a fluorescence turn-on mechanism in the presence of a target. The detection limit of PSA was achieved to be 13 pM for MoO3 NSs, whereas the MoS2 and MoSe2 systems exhibited a detection limit of 72 and 157 pM, respectively. The in vitro bioimaging measurements were also performed using confocal fluorescence microscopy. Herein, PSA detection was successfully demonstrated in human embryonic kidney 293T (HEK) live cells. Moreover, the MoO3, MoS2, and MoSe2 NSs exhibit excellent biocompatibility and low toxicity; thus, these 2D NSs can be used as a promising sensor platform to detect prostate cancer. More chemical and bio-sensing applications will be reported based on the nanomaterial of transition metal dichalcogenides.
Biography: Ding-Bang Xiong is an associate professor in the State Key Lab of Metal Matrix Composites, in Shanghai Jiao Tong University, China since 2012. He received Ph.D. degree in material physics and chemistry from Shanghai Institute of Ceramics in 2007. Between 2007–2010, he carried out his postdoctoral research as Alexander von Humboldt fellow in Marburg University, Germany, and between 2010–2012, he did collaboration research in Kyoto University supported by the Japan Society for the Promotion of Science. His current research focuses on fabrication and properties of metal matrix composite materials.
Abstract: As compared to pure metal, metal matrix composites show enhanced mechanical and functional properties, and have been attracting intensive attention. In recent years, graphene (or its derivate) is considering as an ideal and promising reinforcement for metal matrix composites because of its excellent intrinsic properties (such as high mechanical strength and modulus, high thermal and electrical conductivity), superior strengthening efficiency, flexible feature and nanoscale size. The challenges on successful fabricating high performance graphene/metal matrix composites lie in the uniform dispersion of graphene in metal matrix without structural damages, and also strong graphene/metal interface bonding strength. Additionally, more and more researches have paid attention to improve the properties of graphene/metal matrix composites by designing composite architecture, namely spatial distribution and orientation of graphene in metal matrix. In our group, we have been focusing on fabricating advanced graphene/metal matrix composites with enhanced mechanical, electrical and thermal properties. Metal matrix composites usually show higher strength than pure metal, but at the price of decreased ductility and toughness. As inspired by strengthening-and-toughening effect in natural nacre, we have proposed bio-inspiration concept and fabricated graphene/metal matrix composites with a nacre-like “brick-and-mortar” structure. The bioinspired metal matrix composites show very well balanced strength and ductility/toughness. Moreover, by designing on architecture and interface, ultrahigh electrical conductivity has been obtained in graphene embedded in metal matrix, leading to graphene/Cu matrix composites with electrical conductivity even higher than that of silver. Graphene also provide as promising interlayer for high interface thermal conductance in metal matrix composites.
Biography: Professor Lindström is a visiting scientist from the Royal Institute of Technology (KTH) in Stockholm, Sweden. Lindström has experiences encompassing both academic (KTH), institutional (Swedish Pulp and Paper Research Institute Innventia, now RISE) and has also worked ten years in the Paper/Board industry. Lindströms background training is in polymer and physical chemistry and colloid and surface science, but the focus has been on various unit operations in pulp and papermaking, particularly in the areas of paper chemistry and paper forming issues. His focus has been on manufacture and up-scaling of years. During the past nanocellulosic materials and various industrial applications of these materials. As a senior scientist, he will devote his efforts to the use and integration of nanocellulosic materials in the area of water treatments.
Abstract: There is a whole family of different nanocellulosic nature-based materials, which may be divided into, nanocrystalline cellulose (CNC), nanofibrillar cellulose (CNF) and bacterial nanocellulose (BNC) and algal (Cladophora) nanocellulosics (ANC). The history of these nanocellulosics goes back, at least, to the 1940s.
All of these materials have widely different applications, ranging from large-scale papermaking applications to high-end use in, for instance, the medical and electronic materials sector.
The presentation will focus on the manufacture and applications of NFC in the commodity materials sector and is a personal account of the evolutionary patterns and challenges on the road to practical commercial applications.
There have been extensive research and development activities in the field of nanofibrillar cellulose (CNF) materials during the past decades, although microfibrillated cellulose (MFC) was developed already during the late 1970s at ITT-Rayonier in USA. The developments, however, run to a stand still after ITT Rayonier abandoned their development efforts, but R&D was taken up in the late 80s and in the 90s by efforts in Japan (e.g. Daicel and Japanese scientists), who also became leaders of the current developments in the field of CNF materials, particularly in the areas of TEMPO-oxidation pre-treatments, but also in the area of composite applications and in a vast area of high end applications.
The presentation will give a current perspective on nanocellulose developments. The hurdles to be alleviated in order to secure a successful commercialisation of these materials will be highlighted in the presentation.
Biography: Junichi Kurawaki (born in Kagoshima, Japan,inMay 1957) received B.S. degree from Kagoshima University and M.S. degree from Kyushu University, Japan, in 1980 and 1982, respectively. In 1989, I have acquired PhD from Kyushu University.
In 1984, I have been an assistant professor in College of Liberal Arts of Kagoshima University, Japan. In 1985, I have been a lecturer of Kagoshima University and then associate professor in 1989.Moreover, I have moved to Faculty of Science in Kagoshima University and have been professor in 2007. Since 2011, I have been a vice dean of this Faculty of Science and a head of Natural Science Center in Kagoshima University.
◇Affiliation society is in the following :
The Chemical Society of Japan,
The Society of Nano Science and Technology,
The Japanese Photochemistry Association.
Molecular spectroscopy, Nano material chemistry, Photochemistry,
Abstract: Gold nanoparticles (AuNPs) exhibit many unique electronic, catalytic, optical, and other physical and chemical properties that their bulk counterparts do not have. AuNPs have been applied in many fields including photonics, micro-electronics, photocatalysis, lithography, and surface-enhanced vibrational spectroscopy. Chitosan is a polysaccharide composed of glucosamine and N-acetylglucosamine. Because of its bio-compatibility, chitosan has found emerging applications in biomedicine. In this study, we report a novel synthesis method of chitosan (Cht) supported gold nanocomposite particles (AuNP-Cht NC) using a simple Hg lamp irradiation. The aqueous solution of 1.0 mM HAuCl4 was ligand exchanged to HAu(OH)4 that raised to pH 7.0 with 4 mM of NaOH to prevent the dissolution of Cht. We confirmed to this ligand exchange by change of absorbance spectrum and the solution color turned from yellow to clear. The as-synthesized AuNP-Cht NC was characterized with UV-vis absorption spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) and the average size of AuNPs in AuNP-Cht NC could be determined to be 18.4±8.0 nm. Furthermore, it has been found that AuNP-Cht NCs effectively catalyze the reduction of p-nitrophenol to p-aminophenol in the presence of NaBH4 and this reduction reaction of the present systems follows the pseudo-first-order rate kinetics.
Biography: Dr.Paisan Kongkachuichay is a Professor at the Department of Chemical Engineering, Faculty of Engineering, Kasetsart University, Bangkok, Thailand. He obtained his B.Sc. in Chemical Engineering from Chulalongkorn University and M.S. and PhD in the same field from Texas A&M University, College Station, TX, USA. He is working on nanostructured catalysts for CO2 conversion and NOx reduction. He has published over 40 articles in high-rank journals.
Abstract: CO2, a major greenhouse gas, was converted to methanol via a direct hydrogenation using Cu-Zn metal loading on graphene-based support. The nitrogen-doped reduced graphene oxide (N-rGO) was prepared via the chemical exfoliation of graphite and using hydrazine as a reducing agent. The reduced graphene oxide aerogel (rGOae) was synthesized via hydrothermal reduction. The Cu-Zn on graphene-based supports were then synthesized via an incipient wetness impregnation and tested its performance for methanol synthesis from CO2 hydrogenation under the reaction conditions of 15 bar and 250 °C. The effect of bimetallic compounds Cu-Zn loading content was investigated. As a result, the 10 wt% Cu-Zn loading on N-rGO exhibited the highest space-time yield of methanol because it provides the highest surface area. Additionally, the effect of the H2 reduction time was investigated by in situ X-ray absorption near-edge spectroscopy (in situ XANES). It was found that the optimum reduction time of 90 min for a 350 °C-reduction achieved the highest space-time yield of methanol under the same reaction condition by using the 10%CuZn/N-rGO catalyst due to an almost completely reduced catalyst with low sintering. Moreover, it was found that N-rGO support can facilitate the dispersion of Cu-Zn metals. Especially, the nitrogen-doped atoms from the support can create polarity and facilitate the hydrogen dissociation, which can enhance the methanol synthesis from CO2 hydrogenation.
Unfortunately, N-rGO can restack, attributing to the low surface area. In order to solve this problem, N-rGO will be modified to be a three-dimensional rGOae. The effects of the hydrothermal reduction temperature of rGOae support and Cu-Zn metal loading contents were investigated. Moreover, the role of each nitrogen by using different nitrogen sources (i.e., ammonia, hydrazine hydrate, and urea) doping to rGOae has been investigated. It was found that the hydrothermal reduction at 140 °C provided the highest surface area (458 m2 g−1), and 15wt%Cu-Zn/rGOae catalyst achieved the highest methanol production (94.53 mgMeOH gcat−1 h−1). Furthermore, 15%CuZn loaded on nitrogen doped graphene aerogel catalyst using urea as a precursor provided the highest space-time yield of methanol (405.49 mgMeOH gcat−1 h−1). It was found that the increase of pyridinic nitrogen can greatly promote the catalytic performance and enhance the methanol production.
Nanostructured / nanoporous Materials and devices
Biography: Hideya KAWASAKI, Professor of the Department of Chemistry and Materials Engineering, Kansai University, received a Doctor degree (1996) in Science from Kyushu University. Since 1999, he worked as an assistant professor at Kyushu University. In 2006, he moved to be an associate professor at the Department of Chemistry and Materials Engineering, Kansai University, and he was promoted to a full professor in 2012. He received Awards for Younger Researchers from Division of Colloid and Surface Chemistry from the Chemical Society of Japan (2003) and the Mass Spectrometry Society of Japan (2011). His current research topics include the fabrication and characterization of colloidal metal nanoparticles/nanoclusters, as well their applications for electronics, sensing, catalysis, biomedical applications, and mass spectrometry. He has published more than 180 papers.
Abstract: Flexible electronics have recently drawn considerable attention due to their promising applications such as flexible display, radio-frequency identification (RFID), sensors for the Internet of Things (IoT), and wearable sensors for human healthcare. Conductive inks for printing conductive electrodes/patterns onto flexible substrates (i.e., printed electronics) is crucial to launch the new era of flexible electronics. The printed electronics allows the use of flexible substrates, which lowers production costs and enables fabrication of flexible electrode. Both organic and inorganic-based conductive inks are used for the printed electronics. Thus, conductive inks are key technology for the development of flexible electronics.
Silver-based inks comprising of silver nanoparticles or silver complex have been developed due to high conductivity, low-temperature processes, and high stability. More recently, copper-based conductive ink is of great interest to the printed electronics industry because of their high bulk conductivity, low cost, and low migration tendency. The major issue with Cu-based inks is easy oxidation in ambient air; the presence of copper oxide raises the sintering temperature and dramatically increases the electrical resistivity.
To overcome these limitations, our group focuses on low-temperature sintering of Cu-based inks to produce conductive Cu films on flexible polymer/paper substrates, ensuring the durability of sintered Cu films to safeguard their environmental stability and mechanical ﬂexibility. These performances have become the most important task from a practical standpoint for flexible electronics. We have developed novel copper-based inks to allow low-temperature (<150 °C) sintering for the preparation of conductive Cu films: (i) nanoparticle-based inks with specific ligands[1,2,3,6], (ii) precursor-type inks (e.g., inks based on metal−organic decomposition, MOD)[4,5] and (iii) composite inks of micron-sized Cu particles with Cu nanoparticles or Cu complex [7,8]. In this presentation, we will mainly present a first attempt on air-atmosphere sintering of Cu -based inks at low temperatures [7,8].
Biography: Prof. Yung-Chun Lee received his PhD in Theoretical and Applied Mechanics from Northwestern University, IL, USA. He joined the Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan in 1997 and is now a distinguished professor. His research interests include solid mechanics, experimental mechanics, piezoelectric devices, laser micromachining, nano-imprinting, contact printing, roll-to-roll imprinting, and maskless lithography. His research works are closely related to developing unconventional manufacturing methods of micro/nano-structures with specific applications in industry. Examples are patterned sapphire substrates in LED industry, moth’s eyes nano-structures on curved surface in optics, and nano-scaled gratings in laser diodes for optical communication.
Abstract: This presentation introducesseveral innovative methods for fabricating micro/nano-structures with specific engineering applications. The goal is to achieve nano-patterning and nano-fabrication using relatively simple equipment and inexpensive processes. In the past one decade, the author has developed several nano-fabrication methods based on the ideas of nano-imprinting and contact printing lithography. First of all, a soft photomask lithography method is developed to improve the patterning resolution of conventional contact-type photolithography from m to sub-m. This method has been used for fabricating conical-shape micro-structures on sapphire substrates to enhance light extraction efficiency of LEDs. Secondly, a metal contact printing lithography has been developed for patterning metallic nano-structures. Arrays of metallic nano-particles with highly uniform particle size can be deployed precisely on a substrate. Localized surface plasma resonance (LSPR) can be excited for many biomedical and optoelectronic applications. Thirdly, a curved surface lithography can directly pattern nano-structures not only on a planar substrate but also on a convex or concave surface. Finally, a new type of nano-imprinting lithography based on transferrable and sacrificial polymer imprinting molds is successfully developed. It has been adopted in optoelectronic industry for mass-production of linear gratings of 100 nm line/space for distributed feedback laser diodes (DFB-LDs) used in high-speed optical communication. The common features shared by all the proposed methods are small feature size (sub-micrometer or nm), large patterning area size (~8”), high throughput, using simple equipment readily available in laboratories, and cost-effective.
Biography: Philipp Zimmermann received his master’s degree in chemical engineering from the HTW Dresden-University of applied Science in 2015. Since then he is a scientific employee at Leibniz Institute of polymer research Dresden e.V. Together with Dr. Jürgen Nagel he works in the field of chemical functionalization of nanoparticles and their immobilization on polymer part surfaces during moulding.
Abstract: Nanoparticles and, particularly, nanoparticle aggregates exhibit some very interesting properties which may be used in advanced devices. Some examples are information storage, sensors, microfluidics, or switchable surfaces. For most of the applications, the nanoparticle structures have to be immobilized reliably on solid surfaces.
As a way for immobilization, we followed an approach used for process-integrated surface modification of thermoplastic parts during injection molding. According to that, a layer of nanoparticles was prepared on a solid substrate. This was realized by adsorption from colloid solution, by spray-coating or other methods. Different types of nanoparticles and also microparticles were investigated, like gold, silica, polymers, and inorganic salts. The surfaces of the particles were chemically modified in advance. The layer was characterized by different spectroscopic and microscopic techniques. The particles were randomly distributed over the surface. In some cases chain-like aggregates were formed. The behavior of the layer in contact with the flowing melt was investigated. The substrates were mounted on the surface of a special prepared mould of an injection moulding machine, and the melt was injected. Finally, the surface of the part produced by injection molding was characterized.
It was found, that the nanoparticles were organized in a thin layer on the polymer surface. They were not shifted by the flowing melt. No re-mixing with the flowing melt occurred. The distribution on the thermoplastic part surface was also randomly. Even aggregates from the substrate surface were reproduced. This may be a result of the fast cooling of the melt as it comes in contact with the mold. The process is analyzed by thermal simulation. The degree of embedding (see figure 1) depended on the size and surface properties of the particles. Thus, the embedding depth can be controlled. Some of the particle surface area was accessible for small molecules from solution. This was demonstrated by their catalytic activity in a redox reaction and by their adsorption behavior. Those embedded nanoparticle layers may be used in microfluidics or sensor applications. Moreover, the presentation gives an overview about surface modification effects of thermoplastic parts by embedding of different nanoparticles. The contribution addresses aspects of manipulation and engineering of nanoparticle systems under conservation of their typical properties. With the method introduced, the economic manufacture of parts with surfaces functionalized with nanoparticles becomes possible.
Biography: Ge Wang received her Ph.D. in Chemistry from the Michigan Technological University in 2002. Currently she is a professor and Ph.D. supervisor in the School of Material Science and Engineering at the University of Science and Technology Beijing. In 2012, she became a special chair professor endowed by the Chang Jiang Scholars Program of the Ministry of Education. Her research interests focus on creating complex materials structures with nanoscale precision using chemical approaches, and studying the functionalities including catalytic, energy storage and energy saving properties etc.
Abstract: Energy storage capacity and heat transfer ability are two important indexes of shape-stabilized phase change materials (ss-PCMs). Typically, porous materials can stabilize the PCMs by the surface tension action and capillary forces. However, supporting materials with high porosity usually lead to amorphous structures and low thermal conductivity, which is inadequate for meeting most power conversion targets. Thus, developing supporting materials with large encapsulation capacity and high thermal conductivity still remains a challenge.
Recently, our group developed a one design many functions strategy to design 3D porous carbon support for phase change materials. For example, A novel CNT/mesoporous carbon support for phase change materials (PCMs) have been successfully synthesized by carbonizing a core-shell structured CNT/MOFs template. Porous carbon exhibits high porosity and a large specific surface area which is suitable for encapsulating PCMs. CNTs, acting as heat transfer pathways, constitute continuous channels for phonons transfer and realize rapid heat transformation from ss-PCMs to the outside. 3D conductive network carbon has been synthesized by employing direct-calcined CQDs-derived 3D porous carbon from the aldol reaction. Constructing 3D network succeeds in effective regulation of the channels by crosslinking reaction between DVB and acetone derivate, thus better loading macromolecule PEG and fully releasing crystallization behavior. Highly graphitized sp2-hybrid carbon nanosheets, obtained by direct pyrolysis, providing thermally conductive network and substantially improving thermal conductivity. These ss-PCMs exhibit excellent thermal conductivity and power capacity.
Biography: Chia-Hua Chan received his PhD from the Department of Chemical and Materials Engineering of National Central University, Taiwan. In 2006, he became a postdoctoral fellow at NCU to research fabricating photonic crystals by nanospheres. In 2010, he joined the Institute of Energy Engineering of NCU as an associate professor. His current research interests are using nanostructures to apply on LEDs and solar cells.
Abstract: In this study, we used Single-Step and anti-solvent methods to fabricate a MAPbI3-based perovskite solar cell. However, using the toluene as an anti-solvent will induce the "Marangoni effect" due to difference of the surface tension at the interface between the dripped solvent and the perovskite precursor. This effect will cause non-uniform distribution of the intermediate phase, which will form unexpected voids inside the perovskite layer leading to a low-quality perovskite film. Therefore, we introduce a simple delayed-annealing method to achieve a high quality and high-coverage perovskite layer, which can significant improve the non-uniform distribution of the intermediate phase. We use the SEM, XRD, AFM and EIS to observe and analyze the quality of perovskite films. In comparison with the control sample, the PCE will increase from 13.58% to 18.02% with the sample annealing at 100℃ for 40 min. Moreover, to replace the traditional toxic anti-solvent and realize a rapid process of forming a high-quality perovskite film, a low-toxic anti-solvent ethyl acetate was chosen to rapidly fabricate high-quality perovskite layers with the advantages of low surface tension and high evaporation rate. After using EA as the alternative anti-solvent, the highest PCE is 16.39% with dripping the ethyl acetate. Although the PCE is lower than using traditional toluene as the anti-solvent, it’s unnecessary treating with annealing process for 40 mins to suppress the Marangoni effect which has benefits to reduce the time and cost of fabricate the perovskite solar cells.
Biography: Tatsuhiko Aizawa did his PhD in 1980 at University of Tokyo. During 1981-84 acted as Assistant Professor at University of Tokyo. And from 1985-95 he is an Associate Professor at ibid. From 1996-04 as a Professor at ibid. He acted as a Research Professor, University of Toronto and Professor at Shibaura Institute of Technology. From 2018 he is working as an Professor, Director, Surface Engineering Design Laboratory, Shibaura Institute of Technology, Japan. He wrote 15 Books; 550 Research Papers, 76 Patents
Abstract: Low temperature plasma nitriding had a potential to modify the austenitic stainless steel with the nano-structured surface layer. AISI316 stainless steel tool substrate was employed in the present study to demonstrate this possibility to change the authentic, coarse grained microstructure into the two-phase, fine grained surface layer with the average grain size less than 100 nm. First, a mirror-polished AISI316 substrate was plasma nitrided at 673 K for 14.4 ks by 70 Pa; the modified surface layer thickness reached to 60 mm. XRD analysis proved that no chromium and iron nitrided were synthesized as a precipitate in matrix by this nitriding. SEM-EDX was utilized to describe the cross-sectional microstructure from the surface across the nitriding front end to the depth of matrix. Nitrogen content is preserved to be constant by 5 mass % in the nitrided layer. Inverse pole figure mapping by EBSD analysis proves that this nitrided layer has homogeneous nano-structure with fine grain size less than 100 nm and large misorientation angles. Phase mapping showed that this layer turned to be -’-phase with the volume fraction of a’ more than 70 %. Micro-Vickers hardness testing revealed that this layer had higher hardness than 1400 HV in average. This two-phase nano-structuring was preferable to the usage of AISI316 substrate as a die and mold material for stamping and injection molding
Biography: Jackson Smith obtained his bachelor’s degree in Aerospace Engineering at RMIT University, Melbourne, Australia in 2015. Jackson is currently undertaking his PhD at RMIT University under the supervision of Distinguished Prof. Ma Qian in the field of metallurgical design and dealloying fabrication.
Abstract: Bacterial infection is one of the leading threats to global health today, particularly with the rise of antibiotic resistant bacteria species. Bleak predictions by the World Health Organisation estimate up to 10 million infection-related deaths per annum by 2050 if this intensifying threat is not curtailed. In the fight against these deadly pathogens,the development of new antibiotic drugs should go hand in hand equally with effective infection prevention control solutions. In this work, the design and fabrication of nanostructured copper substrates with outstanding intrinsic bactericidal propertiesis demonstrated. The fabrication process utilizes a simple one-step dealloying method capable of producing either surface or bulk copper nanostructures with the potential to actively eliminate bacteria in a wide variety of applications. Moreover, unique hierarchical structures are demonstrated through a novel tailored metallurgical design process prior to chemical dealloying. Culturing of the common and potentially deadly Staphylococcus aureus bacteria on these nanostructured copper surfaces eliminated 108 CFU/mL within only 2 minutes of exposure, compared to 4 hours on polished copper. Here, the characteristic surface copper nano-ligaments had a profound effect on membrane integrity as within this short exposure period, adhered cells showed extensive blebbing, total loss of structural integrity and leakage of intracellular material.