Synthesis of Nanomaterials
Biography: RongwenLyu received her PhD in fine chemicals from Dalian University of Technology in 2000. She is currently a professor in State Key Laboratory of Fine Chemicals at Dalian University of Technology. Her research directions include controlled synthesis of multifunctional nanomaterials, catalysis and environmental-friendly syntheses for intermediates and fine chemicals.
Abstract: As significant species of artificial photonic crystals, spherical crystals have attracted great attention. However, the variation of nanospheres for buildingcrystalline arrays is still insufficient for large-scale application and the diversity of them remains to be increased. The enhancement of structural color visibility is another noteworthy subject and fabricating composite particles containing black materials to eliminate the disturbance of scattering and background light is an effective method. Herein, a composite of poly(m-phenylenediamine) in-situ coating m-phenylenediamine-based polymer sphere has been synthesized for building bright iridescent structural color by developing the visible light absorption character of the shell. To our knowledge, this is the first work to use poly(m-phenylenediamine) as stray light absorber to wrap the monodispersednanospheres still with high uniformity, and such the designation provides new optional black additive and candidate material for wider applications on spherical crystals.
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: Development of novel methods for controlled synthesis of nanoparticles has enabled a huge range of applications in ceramics, polymers, food industry, and pharmaceuticals. To optimize the synthesis process, accurate characterization of nanoparticles is required to fully understand the size distribution, composition and functional properties.
The conventional technique of electron microscopy with EDS provides imaging and elemental analytics to evaluate the surface morphology and chemical distribution at the sub-10 nm scale on both conductive and non-conductive samples. However, to study the functional properties of these materials, chemical states, phase and molecular information beyond the elemental distribution is essential. Techniques such as Correlative SEM-Raman imaging and spectroscopy have become important tools for further understanding and optimization of the fabrication process in various applications. The ability to employ the high resolution imaging with electron microscopes with in-situ chemical mapping using Raman technique on the same nanoparticle has enabled accurate multi-modal study.
In addition to electron beams, Helium and Neon ion beam microscopes based on a novel gas field ion source have also been employed for high resolution imaging and chemical analysis when combined with secondary ion mass spectroscopy (SIMS). High-resolution imaging with sub nm resolution and SIMS chemical mapping with lateral resolution <15 nm provides a correlative imaging and analytical platform beyond current capabilities especially for studying organic and low Z materials such as Li. When combined with powerful machine learning based segmentation capabilities, the connection and correlation of data from various modalities can provide new insights in nanoparticle research.
Biography: Prof. Lun Dai is currently the director of Institute of Condensed Matter and Material Physics, School of Physics, Peking University. She received her Ph.D. in semiconductor physics from Peking University in 1999. Prof. Dai has published more than 100 SCI papers, which are cited by SCI papers for more than 5000 times. She obtained the National Science Foundation for Outstanding Youth in 2011. Her research interest is two dimensional materials and related devices.
Abstract: Among the Mo- and W-based two-dimensional (2D) transition metal dichalcogenides (TMDCs), MoTe2 is particularly interesting for phase-engineering applications, because it has the smallest free energy difference between the semiconducting 2H phase and metallic 1T’ phase. In this work, we reveal that, under the proper circumstance, Mo and Te atoms can rearrange themselves to transform from a polycrystalline 1T’ phase into a single-crystalline 2H phase in a large scale. We manifest the mechanisms of the solid-to-solid transformation by conducting the density functional theory calculations, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. The phase transformation is well described by the time-temperature-transformation diagram. By optimizing the kinetic rates of nucleation and crystal growth, we have synthesized single-crystalline 2H-MoTe2 domain with a diameter of 2.34 mm, centimeter-scale 2H-MoTe2 thin film with a domain size up to several hundred micrometers, and the seamless 1T’-2H MoTe2 coplanar homojunction. The 1T’-2H MoTe2 homojunction provides an elegant solution for ohmic contact of 2D semiconductors. The controlled solid-to-solid phase transformation in 2D limit provides a new route to realize wafer-scale single-crystalline 2D semiconductor and coplanar heterostructure for 2D circuitry.
Biography: NilgünKalayciogluOzpozan completed her undergraduate studies at Middle East Technical University and completed her graduate studies at Erciyes University Faculty of Science, Department of Chemistry. There are 50 SCI-SCI expanded scientific publications. She took part in 40 projects as an executive. He trained many postgraduate students. There are many awards in research and development projects.
Abstract: Dye-sensitized solar cells (DSSCs) have attracted much attention due to their simple synthesis processes, decent power conversion efficiency (PCE) and fashionable colourful designs . The power conversion efficiency of the advanced DSSCs has over 13%, which is almost equal to that of silicon based solar cells. DSSCs are composed of a dye-sensitized photo-anode on a TCO (transparent conducting glass), an electrolyte (liquid or solid) and a Pt coated counter electrode. To date, TiO2-anatase nanoparticles are typically applied to the porous oxide electrodes. TiO2 nanoparticles with large surface area can adsorb a great amount of dye molecules, giving a large light harvesting and an efficient electron injection [2,3].Herein, an organic-organic hybrid nanoflowers was fabricated from a protein, copper(II) salt and phosphate buffer which formed Protein/Cu3(PO4)2.3H2O hybrid flowers and characterized with FT-IR, XRD, SEM-EDX etc. The fabricated Protein/Cu3(PO4)2.3H2O hybrid nanoflowers was used as second layer in dye-sensitized solar cells (DSSC) and tested.
Biography: Professor Jin Shen obtained his B.S. degree from Northeast Heavy Machinery Institute, China, in 1985, the M.S. degree from China Agricultural University, China, in 1996, and his Ph.D. degree from University of Shanghai for Science and Technology, China, in 2004. He is currently a professor in School of Electrical and Electronic Engineering (SEEE) at Shandong University of Technology (SDUT), and the member of academic committee of SDUT, director of the professor committee of SEEE. His current research interests involve particle sizing, scattering measurement and weak signal detection. He has completed over 30 research projects, including Frequency Decomposition Characteristics of Dynamic Light Scattering Signal of Ultrafine Particles supported by the National Natural Science Foundation of China, Fractal Character of Dynamic Light Scattering of Particles supported by the Natural Science Foundation of Shandong Province, On-line Measurement of Grain Moisture during Drying Process supported by Ministry of Agriculture of China. He has published over 200 scientific papers, and received the Science-Technology Progress Prize of Shandong Province for three times. He was a Visiting Professor at University of South Australia from Jun to December 2010, and Visiting Researcher at Kansas State University from October 2012 to August 2013.
Abstract: In particle size measurement with dynamic light scattering, it is still difficult to accurately recover the broad or bimodal particle size distribution (PSD), since the PSD information in the autocorrelation function (ACF) was not being fully utilized. In this work, a method of successive updating of the angular weighting is proposed for the angular weighting calculation. By successive information weighting, the noise of the long delay section of the ACF is further weakened and the information extraction of the middle delay section of the ACF is further strengthened. Compared with the routine inversion approaches, AWSU method could provide better inversion results of the broad distribution and near bimodal distribution particles. In the comparison, it is also shown that an accurate angular weighting calculation could reduce the number of scattering angles required and, during the successive updating of the angular weighting, the repeated weighting did not only contribute to the accuracy of the angular weightings, an indirect approach acting on inversed PSDs, but also directly to PSD inversions by reconstructing ACFs with PSDs obtained by weighted inversion. The combination of these two contributions both reduces the number of scattering angles needed, and keeps the PSD inversions from getting worse caused by excessive scattering angles.
Biography: Dr. Hui Pan is an associate professor in the Institute of Applied Physics and Materials Engineering at the University of Macau. He got his PhD degree in Physics from the National University of Singapore in 2006. From 2008 to 2013, he had worked at National University of Singapore as Research Fellow, Oak Ridge National Laboratory (USA) as Postdoctoral Fellow, and Institute of High Performance Computing (Singapore) as Senior Scientist. He joined the University of Macau as an assistant professor in 2013. In his research, a combined computational and experimental method is used to design novel nanomaterials for applications in energy conversion and storage (such as solar cells, water-splitting, Li batteries, supercapacitors, hydrogen storage, and fuel cells), electronic devices, spintronics, and quantum devices. He has published more than 125papers in international peer-reviewed journals, such as Phys. Rev. Lett., Phys. Rev. B, Adv. Mater., Chem. Mater., ACS Nano, J. Phys. Chem. B&C. The total citation is more than 5800 (google scholar)/4800 (SCI). Additionally, he is the author of 5 book chapters and the inventor of 4 USA and 1 China patents. His present h-index is 36 (google scholar)/33 (SCI).
Abstract: Abstract: Hydrogen (abundant, clean and renewable) has been considered as one of the most important green energy sources to cater the increasing demand for energy in the future due to the limited supply of the old forms of depletable energy (coal, oil, nuclear) and their detrimental effects on the global climate. Water splitting has attracted increasing attention due to the versatile applications of hydrogen and oxygen gases. Generally, there are two ways for the water splitting, including solar-driven hydrogen production and electrical-driven electrolysis of water. In this talk, I will present our recent work on the hydrogen production using the two methods based on materials’ design and experiment fabrication, including including: (1) Design of photocatalysts for solar-driven hydrogen production. We will present a new concept on the engineering of electronic properties. (2) design and fabrication of two-dimensional (2D) transitional metal dichalcoginides as efficient electrocatalysts for electrical-driven hydrogen production. We showed that the catalytic performance of 2D MLs can be tuned by surface engineering. (3) design and fabrication of doped nanowires as efficient electrocatalysts. We found the doping can dramatically improve the efficiency. (4) Our first-principles design showed that the MXenes can be efficient electrocatalysts for electrolysis of water and co-catalyst in solar-driven water splitting. (5) graphitic carbon nitride with cocatalysts for solar-driven production. The approach enables the enhanced carrier mobility and electron-hole separation, and improved photocatalytic activity in the visible light region and thus offers immense potential for application in solar energy conversion, water splitting, and a variety of solar-assisted photocatalysis.
Biography: George H. Beall is a Corporate Fellow (retired) and Consultant in the Science and Technology Division of Corning Incorporated, Corning, NY.He joined Corning in 1962 after receiving his PhD in Geology from the Massachusetts Institute of Technology. He also holds B.Sc. and M.Sc. degrees in Physics and Geology from McGill University. He was a Courtesy Professor in the Department of Materials Science and Engineering at Cornell University for 10 years. Dr. Beall has authored/co-authored over 80 technical papers and holds over 120 US patents. He has co-authored one book and edited another.
Dr. Beall received the Chemistry of Materials Award from the American Chemical Society in 1995, and the 2001 Achievement Award from the Industrial Research Institute. He is an Academician of the World Academy of Ceramics, and was awarded an honorary Doctorate from Alfred University in 2017.
Dr. Beall is a Distinguished Life Member of the American Ceramic Society and a Member of the Glass and Optical Materials Division. He received the Division’s George Morey Award in 1988, and the Society’s John Jeppson Award and Samuel Geijsbeek Award, both in 1993. He delivered the Edward Orton Memorial Lecture in 1996, and received the W. David Kingery Award in 1997.
Dr. Beall’s primary field of research involves the controlled crystallization of glass and resulting glass-ceramic materials and products made therefrom.
Abstract: Nanocrystalline glass-ceramics are formed by efficient internal nucleation and high-viscositycrystallization of previously formed glass objects.This is generally accomplished bya two-stage heat treatment.There is typically minor shrinkage during this process but little or no deformation or shape change. Glass-ceramics are characterized by uniform microstructure and zero porosity. Special glass compositions designed to achieve desirable crystal assemblages also contain dissolved nucleating agents like TiO2, ZrO2 and P2O5, which promote fine crystallization (<100 nm)during reheating cycles. Amorphous phase separation often precedes the formation of crystalline nuclei, typically titanates, zirconia or orthophosphates of <15 nm size.
Most nanocrystalline glass-ceramics are derived from aluminosilicate glasses modified by Li2O, MgO, ZnO, Na2O and K2O. The important crystal phases and their desirable properties are β-quartz solid solution, primarily SiO2-LiAlSiO4, characterized by low or even zero coefficient of thermal expansion; spinel, with high hardness and elastic modulus; Cr-doped mullite, with luminescence matching the spectral response of silicon; Cr-doped forsterite, with broadband i-r luminescence; nepheline, with good ion exchange strengthening capability; and lithium disilicate and petalite, both improving fracture toughness. Most nanocrystalline glass-ceramics, including all those above, aretransparent.
Forming of the parent glasses without devitrification requires a sufficiently high viscosity at the liquidus temperature to allow conventional high-speed processes like rolling, downdraw, fiberizing, pressing, and blowing. The major long-lived nanocrystalline commercial products are electric range-tops, transparent cookware, and telescope mirrors. Prospective products include broad-band amplifiers, photovoltaic substrates, and faceplates and housing for mobile electronic devices.
Biography: Raphael Haumont is an Associate Professor, solid state chemistry, innovation in cristalline growth, Paris-Saclay university
Abstract: Single crystals of CaTiO3,BaTiO3,and LiNbO3 were prepared by the floating method (FZ) method in which a high external electric field (≥ 3 kV.cm-1) is applied. Such an electric fieldis a new powerful tool, in crystalline growth,able to create new chemical structures and original new materials with new physical properties. By varying crystal growth velocity and electric field strength, we show that we can control the macroscopic shape of single crystals, and we can alter the crystalline orientation of domains;
Applying an in-situ high electric field during crystalline growth is a new tool to design domain modulated-structures. Recent works reported the role of the electric field on kinetic and thermodynamic processes during crystalline growth. In the selection, orientation and distribution of piezoelectric domains, we have shown that an electric field acts like an external force [1,2]. The electric field can act on thermodynamic equilibrium and on a solid/liquid interface . Its application during growth modifies the partition coefficient of species  and the possible modification phases diagrams of a material . Indeed ions within a difference of electric potentials see their energy changing, which implies a new thermodynamic equilibrium . Thus, applying an intense electric field during compound growth is a new parameter to affect the direction of polarization and possibly to amplify the value of polarization by exacerbating ionic displacements.
Biography: Nalan Özdemir has her expertise in biochemistry, especially separation and purification of enzymes, enzyme immobilization, preparation and characterization of enzyme-inorganic hybrid nanostructures. Dr.Özdemir is the founder of the Biochemistry Division at Chemistry Department, Faculty of Science-Erciyes University/TURKEY. She began her studies about synthesis and also characterization of organic-inorganic hybrid nanoflowers. Dr.Özdemir has done many projects and published several articles about organic-inorganic hybrid nanoflowers. Dr Özdemir's work still continues in this area.
Abstract: Organic-inorganic hybrid nanoflowers are a newly developed class of nano materials showing structure similar to flower. These kinds of hybrid nanoflowers are gaining much attention due to their simple method of synthesis, high stability and enhance efficiency. They are composed of several layers of petals. For this reason hybrid nanoflowers show high surface to volume ratio and the efficiency of surface reaction is increased in the three dimensional structure of them. Because of high surface area of the hybrid nanoflowers, they can be used for several applications include catalysis, biosensor, drug delivery etc[1,2].
In this work, aorganic-organic hybrid nanoflowers was synthesized for solar cell application. For this purpose,a protein was used as the organic component and Cu3(PO4)2.3H2O was used as the inorganic component under the mild conditions. After preparation step some important features (structure and morphology, encapsulation yield, weight percentage etc.) of the hybrid nanoflowers as a function of synthesis conditions (metal ion and enzyme concentrations, pH) were studied. Synthesized hybrid nanoflowers were characterized by SEM, EDX, FTIR, XRD, and UV-Vis.
Nanoparticles Synthesis and applications
Biography: Hongwu Tang received his BS (1991) and Ph. D. (1997) in analytical chemistry from Wuhan University. He is now a full professor of chemistry in Key Laboratory of Analytical Chemistry for Biology and Medicine (MOE) & College of Chemistry and Molecular Sciences, Wuhan University, China. He is Member of Chinese Chemical Society, Chinese Optical Society and Chinese Society of Micro-Nano Technology. He was a visiting scholar in School of Physics and Astronomy, University of Leeds, UK (2006) and a visiting professor in Niels Bohr Institute, University of Copenhagen, Denmark (2014). His recent interests focus on nanomaterials and nano-biosensors as well as construction and applications of novel detection platforms based on biomedical optics.
Abstract: Design and synthesis of colloidally stable water dispersible upconversion nanoparticles with intense luminescence are difficult, particularly for quantitatively analyzing luminescence properties of single nanoparticles. Herein, on the basis of constructing multifunctional optical tweezers (OT) equipped with a 980 nm continuous-wave (CW) single-mode diode laser beam and multiple detectors, we are able to trap single upconversion nanoparticles (UCNPs) stably as well as synchronously analyze their luminescence properties. Successive trapping of individual octylamine-modified poly(acrylic acid) encapsulated UCNPs (OPA-UCNPs) is verified by real-time monitoring of forward scattering (FSC), luminescence intensity and spectra of the trapped particles, and we found that these nanoparticles possess excellent colloidal stability and uniform luminescence properties. Besides, ligand/solvent-dependent surface quenching effect of single UCNPs is investigated, and the results show that OPA modified UCNPs by hydrophobic encapsulation strategy possess outstanding luminescence properties and the property of OPA reducing the quenching effect of ligands and water molecules are well identified. Upconversion luminescence decay lifetime also explains the mechanism that the OPA molecules reduce surface quenching effect, thus OPA-UCNPs exhibit longer luminescence decay lifetime. Therefore, we not only provide a new method to evaluate the luminescence properties of single nanoparticles by using multifunctional OT, but also prove that encapsulating hydrophobic UCNPs with amphiphilic molecules is an alternative strategy to prepare monodisperse hydrophilic UCNPs while significantly maintaining their luminescence properties.
Biography: K. Alex Chang received his Ph.D. in the department of Applied Mathematics and Statistics from the State University of New York at Stony Brook. He did his Post-Doc at Indiana University, Bloomington, USA. In 1998 he joined the department of Applied Mathematics, National Pingtung University, Taiwan, ROC. His research interests are in Numerical Analysis, Numerical PDE and Compositional flows in porous media.
Abstract: Simulations of compositional flow involving a gas phase in porous media are of interest and importance in many areas. A challenge to the numerical simulation of compositional flow in porous formations is the change in systems of equations that accompanies the appearance and disappearance of a gas phase. This difficulty can be overcome in several approaches. Collaborating with coworker, the author developed a network flow algorithm that checked on the flow condition (two phase, single-phase under-saturated, single-phase over-saturated) in each pore to determine the appropriate equations to apply . In computations of two-phase, two-component (H2O, CO2) flow in a 3D pore network , we noted the periodic appearance and disappearance of the gas phase in certain pores. Intensive evaluation of our algorithm led us to conclude that the phenomenon was not numerical in origin.
In this talk, we extract a 2x2 dynamical system describing flow through a single pore to study the dynamics of the appearance and dissolution of gas bubbles during two-component (CO2, H2O), two-phase (gas, liquid) flow. Our analysis indicates that three regimes occur at conditions pertinent to petroleum reservoirs. These regimes correspond to a critical point changing type from an unstable node to an unstable spiral and then to a stable spiral as flow rates increase. Only in the stable spiral case do gas bubbles achieve a steady-state finite size. Otherwise, all gas bubbles that form undergo, possibly oscillatory, growth and then dissolve completely. Under steady flow conditions, this formation and dissolution repeats cyclically.
Biography: Prof. Dr. J. Oyun works at the Department of Chemistry and Technology, Ulaanbaatar State University. She graduated from the Chemical Faculty of the Irkutsk State University, Russia; obtained her PhD degree from the Moscow State University of Fine Chemical Technology, Russia in 1984;ScD degree in Mongolia in 2002.
Her main research fields are chemical-technological studies of concentration of trace rare Earth’s elements from ore and mineral objects, processing of natural medical quality minerals by supercritical dioxide carbon method for extracting nano-sized raw materials for medicine, investigation and substantiation of the traditional Mongolian technology for preparing medical raw materials. Prof. J. Oyun published about 300 papers, 10 conference papers, 19 patents, 5 textbooks and 13 monographs.
Abstract: We have studied physical-chemical characteristics of the Mongolian medical minerals and carried out scientific substantiation of traditional Mongolian technology for preparing from them raw materials for medicine. The investigated medical minerals werecollected from Gobi region, Mongolia. Physical-chemical analyses were carried out using X-ray, microscopic, XRD, XRF, and atomic absorption AAS-3, ICP-OES methods.For the medicine raw material preparation,we selected the Iceland spar and a thermo-chemical supercritical CO2 method which is based on the traditional Mongolian technology. The process runs without addition of any chemical salts and without weight loss.
By nourishing the product by milk we obtained new bionanocomposite materialswith the following characteristics: high resolution TEM microscope revealed the size of theCaO amorphous powder is 20 nm, crystalline powder is about 5 nm. In the composition of the nourished spar X-ray powder diffraction (XRD)suggests the formation of (1) lactate calcium co-ferment – Calcium Lutetium Oxalate CaLuC2O4, (2) C3H3LuO6bionanocomposite materials related to CaLu(CH3CHOHCOO)3. Lutetium dissolves in a lactic acid, has small magnetic moment and the smallest radius to compare with other REE. In previous study, we found out that the REE are absorbed in the lattice structure of biogenic origin calcium in a constant amount of quantity.
Such processed spar had been used in the traditional Mongolian medicine practice to treat esophageal cancer.Recovery of REE in medical minerals opens new perspectives in the traditional treatment interpretation.
Biography: Dr. Chen Jinzhou’s research filed include: materials science & engineering addressing on the design of a range of bio-based functional composite materials, particularly focusing on the Polylactide materials and carbon-based materials, and study their applications in packaging and biomedical engineering. So far, he has published 35 academic papers on international academic journals as the first author and corresponding author, including Chemical Engineering Journal, Biosensors and Bioelectronics, ACS Sustainable Chem. Eng., Soft Matter, Journal. Materials & Science, RSC Advanced and Journal of Applied Polymer Science.
Abstract: In this study, Chitosan was used to wrap the graphene layers, and then the wrapped graphene was reduced by ascorbic acid. The results were indicated that chitosan could greatly increase the dispersity of modified graphene and dramatically enhanced the interfacial polarization. We further dispersed modified graphene into polymer matrix and prepared a composites with high dielectric constant and low threshold. The obtained composites was used to fabricate two kinds of capacitive sensors: continuous dielectric units sensor and independent dielectric units sensor array. Those sensors showed high sensitivity and good stability, which would have important applications in capacitive sensing.