Symposium Organizers
" " " Brookhaven National Laboratory
Mato Knez Max Planck Institute of Microstructure Physics
Stanislaus S. Wong State University of New York at Stony Brook
Hongjin Fan Nanyang Technological University
Woo Lee Korea Research Institute of Standards and Science (KRISS)
D1: Bioinspired Approaches
Session Chairs
Tuesday PM, November 29, 2011
Back Bay B (Sheraton)
9:30 AM - D1.1
Seed-Assisted Synthesis of Mordenite Zeolite by Using Indonesian Naturally-Occuring Minerals.
Rino Mukti 1 , Shofarul Wustoni 1 , Agus Wahyudi 2 , Ismunandar Ismunandar 1
1 Division of Inorganic and Physical Chemistry , Institut Teknologi Bandung, Bandung Indonesia, 2 R&D Center for Mineral and Coal Technology (Tekmira), Ministry of Energy and Mineral Resources, Bandung Indonesia
Show AbstractZeolites have found widespread applications nowadays. They have become important to more than just applicable in ion exchange, adsorption (separation) and catalytic chemistry but now, new fields such as microelectronic and metal diagnosis are opened for the development using zeolites. This is due to the fact that zeolites are able to serve as shape selective host for guest molecules. As located in the volcanic area, Indonesia has abundant source of naturally-occuring minerals. These natural minerals contain very low quality of zeolites, therefore in order to bring these minerals into high value, we have implemented seed-assisted synthesis to outcome only one selective zeolite into high quality. For this reason, we have selected the naturally-occuring minerals that are originated from Nanggung, Bogor having almost no crystallinity according to their X-ray diffraction (XRD) diffraction pattern. By utilizing these minerals as seed in such hydrothermal synthesis composition consisting of additional silica and alumina source, mordenite zeolite, one of zeolite types with medium silica content was selectively resulted. Characterization by XRD shows that this mordernite has high crystallinity and scanning electron microscopy (SEM) revealed the crystal morphology. We have concluded that this seed-assisted synthesis still requires additional silica and alumina source. Without these additional compounds, analcime zeolite is only the product that is considered to be less potential for applications than mordenite zeolite.
9:45 AM - D1.2
New Developments for Lignocellulosics - Nanocomposites with Low Carbon Footprint.
Alcides Leao 1 , Bibin Cherian 2 , Sivoney Souza 3 , Suresh Narine 4
1 Natural Resources, UNESP, Botucatu, Sao Paulo, Brazil, 2 Natural Resources, UNESP, Botucatu Brazil, 3 , UFABC, Santo Andre, Sao Paulo, Brazil, 4 Physics, Astronomy and Chemistry, Trent University, Peterborough, Ontario, Canada
Show AbstractMost of the natural fibers are grown in developing or under developed country worldwide, representing an importance source of income for millions of people around the world. The new developments of natural fibers toward the composites production will represent an increase in those economies. Composites reinforced with natural fibers at macro, micro and nano scales are opening new opportunities for may economical deprived areas that depend heavily on crop fibers. The present paper describes new applications of natural fibers in composites, technologies used for nanocellulose production and its application for automotive, biomedical and packaging industries. A carbon evaluation was made to complement its assessment related to biobase index. Pulp and paper primary sludge were treated with 2 % NaOH (fiber to liquor ratio 1:10) in an autoclave and kept under 20 psi pressures for a further period of 1 hour. Pressure was released immediately. The sludge fibers were removed from the autoclave and the fibers were washed in water until it was rid of alkali. The steam exploded fibers were bleached using a mixture of NaOH and acetic acid for the nanocellulose isolation.Microscopy techniques and X-ray diffraction were used to study the structure and properties of the prepared nanofibers and composites. The composition with 4 wt % cellulose was optimal and showed the highest strain-to-failure. The developed nanocellulose and its composites confirmed to be a very versatile material having wide range of biomedical applications and biotechnological applications, such as tissue engineering, drug delivery, Breathable Wound Dressing, Non Latex Condoms, Surgical Gloves, Surgical Gowns, OR Drapes, Hospital Mattresses, Hospital Sheets and Pads, Medical Bags, Tubing, Organ Retrieval Bags, Medical Disposables, Surgical Drapes and medical implants such as artificial heart diaphragms, heart valves, joint prostheses, vascular grafts, urethral catheters, mammary prostheses, penile prostheses, etc.
10:00 AM - D1.3
Hydrolytic Activity of Cellulose Nanocrystal.
Takeshi Serizawa 1 , Toshiki Sawada 1 2 , Masahisa Wada 3
1 Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo Japan, 2 Komaba Open Laboratory, The University of Tokyo, Tokyo Japan, 3 Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo Japan
Show AbstractCellulose is a linear polymer composed of D-glucose, which is linked each other with β1-4 bonds, and is the most abundant organic material in the biosphere. Natural cellulose shows high crystallinity, and is present as composites with other molecules such as hemicellulose, lignin, and/or proteins. Based on adequate purification processes, cellulose nanocrystal, which is stably dispersed in aqueous solution, can be obtained from various natural resources.We are interested in science and engineering of the interface between polymers and biomolecules. Particularly, we have demonstrated the presence of peptides that specifically recognize and bind to the surfaces of polymers, based on phage display methods that utilize peptide libraries prepared on genetically engineered viruses. Surprisingly, during binding analyses of peptides to cellulose nanocrystal, it was discovered that the amide linkage of the peptides bound onto the nanocrystal was hydrolyzed under ambient conditions, producing peptide fragments in the aqueous solution. The hydrolytic activity was independent of amino acid sequences of the substrate peptides. Once peptides bound onto the surface of cellulose nanocrystal, the amide linkages were hydrolyzed successfully.In order to characterize the hydrolytic activity of cellulose nanocrystals, hydrolysis of model organic substrates were analyzed quantitatively by monitoring the products. Not only the peptides but also the model substrates were hydrolyzed, suggesting versatile hydrolytic activities of cellulose nanocrystal. The order of hydrolytic rates were p-nitrophenyl acetate > monophosphate >>acetamide. The hydrolysis well followed a pseudo-first order reaction rate. The rate constant was obviously greater than that for spontaneous hydrolysis. Significantly, cellulose nanocrystals could be reused for repetitive hydrolysis with similar reaction rates, suggesting that the catalytic hydrolysis were preceded. The mechanism for the hydrolytic activity of cellulose nanocrystal will be proposed.
10:15 AM - D1.4
Stabilization of Tyrosinase for Humification Reaction.
Renu Yadav 1 , Swati Kotwal 2 , Nitin Labhsetwar 1 , Mrs. Sadhana Rayalu 1
1 Environmental Materials Divsion, National Environmental Engineering Research institute, Nagpur, Maharashtra, India, 2 University Department of Biochemistry, , RTM Nagpur University,LIT Premises,Amravati Road, Nagpur, Maharashtra, India
Show AbstractThe effect of climate change stemming from the significant increase in atmospheric CO2 levels has necessitated fixing or storing carbon as biomass in terrestrial ecosystems. Humus serves reservoir for carbon storage as an organic matter in soil. Humus is formed in soil in the presence of enzymes like tyrosinase and the process is known as humification. It shall resolve the problem of carbon depletion from soils with concomitant resolution of relentless build-up of the greenhouse gas such as carbon dioxide in the atmosphere. However, one of the major problems encountered with enzymatic reaction is the short life span and less stability of the enzyme in its free form. Efforts are being made at NEERI to overcome this problem; a new enzyme composite of nanometer scale is being developed by using a combination of stabilization and immobilization approach. This enzyme composite is referred to as single enzyme nanoparticle (SENs), wherein each enzyme is coated with organic / inorganic hybrid polymer of less than a few nanometers thick. The major advantages of immobilized SENs includes enzyme stabilization, enhanced reactivity, increased half life of enzyme with high surface area, and reduced mass transfer limitation. SEN-tyrosinase has been developed for its application in humification reaction in a view of CO2 sequestration through humus formation. Immobilization matrices such as mesoporous iron oxide, mesoporous manganese oxide, fly ash and bauxite residue are showing good activity for L-DOPA, used as substrate. The highest activity of 824 U/mg has been observed for SEN-tyrosinase immobilized on mesoporous iron oxide as compared to 625 U/mg for free enzyme. This may be attributed to synergistic effect between matrix and enzyme. SEN-Tyrosinase has been characterized for its elemental composition, protein content and surface morphology. Co-catalysis of humification occurs by three mechanisms involving physical stabilization of tyrosinase (formation of SEN and further immobilization it on different matrices), direct oxidation of the monomers (phenol), and promotion of the oxidation and condensation steps of alkaline pH. Although tyrosinase activity is greatest at neutral pHs, the large pH dependence of the condensation step drives the overall reaction to maximum rates under alkaline conditions. Substantial improvement in the half life period is expected, for which studies are in progress.
10:30 AM - D1.5
pH-Responsive Properties of Bio-Derived Glycolipids and Use as Structuring Agents for Material Synthesis.
Niki Baccile 1 , Florence Babonneau 1 , Bejoy Thomas 1 , Inge Van Boegaert 2
1 LCMCP, CNRS-UPMC, Paris France, 2 InBio, Gent University, Gent Belgium
Show AbstractThe capability of synthesizing natural compounds by some bacteria and/or yeasts is well-known since several decades and the applications of these products were mainly concentrated in the development of new cleansing, skin care products, drugs, polymers, etc... Nevertheless, some of them, and in particular glycolipids, have interesting physico-chemical properties in water. Rhamnolipids and sophorolipids, for instance, are microorganisms-derived water-soluble glycolipids which have the advantage of possessing an internal carboxilic acid function [1]. The physico-chemical behaviour of these biosurfactants is largely unknown but preliminary studies show pH-responsive micellization properties [2,3].Classical surfactants do not show specific pH-dependent aggregation properties, exception made for some classes of well-designed block copolymers based, for instance, on poly(acrylic acid) blocks.In this communication, we describe the pH-driven self-assembly, in aqueous solution, of functional glycolipids (sophorolipids). We show, mainly through Small Angle Neutron Scattering (SANS) and cryo-TEM experiments, the variety of meso and macro-assemblies and how to control them. We will discuss concentration and time-evolution effects and we will outline how the nature of the micellar/water interface changes as a function of pH. Finally, we will show how the properties of these fully natural molecules can be exploited in the synthesis of silica-based thin films and powders [3]. In particular, it will be interesting to see how slight changes in the initial conditions will lead to drastic changes in the material scaffold and porosity at different scales lenghts, from nano to macro. [1] I. N. A. Van Bogaert et. al Appl. Microbiol. Biotechnol., 2007, 76, 23–34[2] S. Zhou et al. Langmuir, 2004, 20, 7926-7932[3] N.Baccile et al., Green Chemistry, 2010, 12, 1564–1567
10:45 AM - D1.6
Morphology-Preserving Chemical Conversion of Intricate Three-Dimensional Micro/Nanopatterned Bio-Organic Structures into Multicomponent Oxide Compounds.
Jonathan Vernon 1 , Yunnan Fang 1 , Ye Cai 1 , Kenneth Sandhage 1
1 MSE, Georgia Institute of Technology, Atlanta, Georgia, United States
Show AbstractThe generation of nanostructured assemblies with complex (three-dimensional, 3D) self-assembled morphologies and with complex (multicomponent) tailorable inorganic compositions is of considerable technological and scientific interest. Self-assembled 3D inorganic templates, of biogenic or synthetic origin, have been converted into replicas comprised of numerous other functional inorganic materials (e.g., Si, Ag, Au, Pd, Pt, TiO2, ZrO2, SnO2, BaTiO3, Eu-doped BaTiO3, Mn-doped Zn2SiO4) by shape-preserving reaction-based and/or coating-based approaches.[1-9] Nature also provides a spectacular variety of biologically-assembled 3D organic structures with intricate, hierarchical (macro-to-micro-to-nanoscale) morphologies. In this presentation, a shape-preserving conformal coating and low-temperature (energy-efficient) reaction process for transforming bio-organic (sustainable) templates into freestanding 3D multicomponent oxide structures will be discussed. This conversion process consists of three general steps: (i) wet-chemical layer-by-layer deposition (to apply a thin, continuous, conformal oxide coating), (ii) organic pyrolysis (to selectively remove the bio-organic template), and (iii) hydrothermal reaction (to generate the desired nanocrystalline multicomponent oxide). This process is demonstrated by converting 3D macro/micro/nanostructured chitinous butterfly scales into barium titanate (BaTiO3). The phase and structural evolution at various steps of this process have been evaluated by electron microscopy, diffraction analyses, and raman spectroscopy. With proper attention to each step, this shape-preserving coat-then-react process may be used to generate macro/micro/nanostructured inorganic assemblies with a wide range of complex 3D morphologies and complex (multicomponent) functional oxide chemistries. [1] J.D. Berrigan, et al.. Adv. Funct. Mater., 21, 1693 (2011); [2] K.H. Sandhage, JOM, 62 [6] 32 (2010); [3] B. Hatton, et al., Proc. Nat. Acad. Sci., 107 [23] 10354 (2010); [4] G. Wang, et al., Adv. Funct. Mater., 19 [17] 2768 (2009); [5] Z. Bao, et al., Adv. Mater., 21 [4] 474 (2009); [6] R.F. Shepherd, et al., Adv. Mater., 20 [24] 4734 (2008); [7] Y. Cai, et al., J. Am. Ceram. Soc., 90 [4] 1304 (2007); [8] Z. Bao, et al., Nature, 446 [3] 172 (2007); [9] K.H. Sandhage, et al., U. S. Patents 7,615,206 (2009), 7,393,517 (2008), 7,204,971 (2007), 7,067,104 (2006).
D2: Synthetic Approaches
Session Chairs
Tuesday PM, November 29, 2011
Back Bay B (Sheraton)
11:30 AM - **D2.1
About the Recent Advances in Mechanochemical Approach to Materials Design.
Viktor Balema 1
1 Materials Science, Sigma-Aldrich Corp., Milwaukee, Wisconsin, United States
Show AbstractThe presentation addresses an experimental approach which proved to be indispensable in basic and applied materials science R&D—the preparation and modification of solid materials on molecular and nano-level using high-energy mechanical processing. This approach, also know as mechanochemistry, offers an extremely convenient way of making novel materials and studying chemical transformations that take place in solids under solvent-free conditions. Recent research suggests that exact mechanisms of mechanochemical processes should be determined on a case-by-case basis. It also appears that mechanochemical processes in solids can be driven by a variety of deformations and the high pressure, generated in the material during milling or grinding.
12:00 PM - D2.2
Hydrogen Storage Properties of Nanostructured Graphite-Based Materials.
Yinghe Zhang 1 , David Book 1
1 , University of Birmingham, Birmingham United Kingdom
Show AbstractIn 1999, Orimo[1] reported that nanostructured graphite produced by milling could absorb up to 7.4 wt% hydrogen. However, high temperatures (up to 600 K) were then required to release this hydrogen, and it was not reversible. In 2005, Ichikawa et al[2] reported that the addition of LiH introduces a degree of reversibility (i.e. allows some hydrogen re-absorption). Ball-milled graphite with Fe (1 at%) (10 bar H2, 80 h) was found to store more hydrogen than pure graphite milled under the same conditions[3]. However, for both these additions, methane was also released during desorption, which will prevent long-term reversibility.In this work, the effect of milling conditions and additions on the microstructure and hydrogen storage properties of graphite milled in a tungsten carbide pot was investigated using TGA, mass spectrometry, XRD, SEM, TEM, Sieverts-PCT and Raman spectroscopy. The TGA and MS results showed that, for a graphite sample milled in hydrogen for 10 hours, the amount of hydrogen desorbed was about 5.6 wt%, and the onset desorption temperature was about 400°C. No methane release could be detected up to 12 hours milling time. The physical properties have been characterised by HRTEM and Raman spectroscopy as a function of milling conditions. HRTEM showed that the interlayer distance changed with milling (Fig. 1). This work discusses how the milling conditions and the type of additions (i.e. LiH, Fe), effect both the structure of the graphite samples and their hydrogen storage properties.References[1]S. Orimo et al, Applied Physics Letters, 1999, 75, 3093-3095.[2]T. Ichikawa et al, Applied Physics Letters, 2005, 86.[3]H. Miyaoka et al, J Alloy Compd, 2010, 507, 547-550.
12:15 PM - D2.3
Synthesis of Crystalline, Metastable Solid Ionic Conductors via a Solution-Based Routine.
Wujun Fu 1 , Zengcai Liu 1 , Zhan Lin 2 , Zili Wu 3 , Xiang Yu 1 , Andrew Payzant 2 , Nancy Dudney 2 , Jim Kiggans 2 , Jane Howe 2 , Kunlun Hong 1 , Chengdu Liang 1
1 Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States, 2 Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States, 3 Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States
Show AbstractSolid electrolytes attract great interests in battery research for their potential use in the next generation of high energy batteries such as lithium-air and lithium-sulfur batteries. In spite of their salient advantages of broad electrochemical window, enhanced safety, and alleviated environmental concerns, the known solid electrolytes have limited use in batteries because of their inadequate ionic conductivity at ambient temperature. New materials with high ionic conductivity are highly desirable in battery research. Among a broad variety of materials showing ionic conductivities, lithium sulfide-based solid electrolyte, in particular, the binary Li2S-P2S5 glass system, which exhibits high lithium ionic conductivity up to 10-3 S/cm and wide electrochemical window over 5 V, attracted much attention recently. The binary Li2S-P2S5 electrolytes are generally synthesized via conventional solid-state synthesis at extremely high temperatures (up to 900 C) under vacuum or through long-period mechanical milling by using a ball mill apparatus. In some cases, materials of high ionic conductivity are metastable phases. The harsh synthesis conditions of high temperature exclude the solid-state synthesis of metastable phases. In addition, some solid-state routines are neither environmental friendly nor suitable for mass production. From the sense of synthesis, a facile, scalable routine, which can precisely control the composition and phase of the final products, is highly desired. Herein, we reported a facile, solution-based synthesis method by using organic solvent as the template to guide the formation of the pure, metastable Li2S-P2S5 crystalline phase. The electrochemical impedance measurements indicated that the prepared crystalline Li2S-P2S5 phase is an ionic conductor exhibiting Li+ conductivity up to 10-5 S/cm at room temperature. This facile solution-based synthesis method is a boon to the pursuit of novel solid lithium superionic conductors.
12:30 PM - D2.4
Ajaokuta Blast Furnace’s Slag as Spin off Materials for Industrial Development.
C. Ocheri 1 , J. Agboola 2
1 Foundry Shop, Ajaokuta Steel Company Limited, Ajaokuta, Kogi Nigeria, 2 Mechanical Engineering Department, Federal University of Technology, Minna Nigeria
Show AbstractSlag is the by-product of smelting ore to purify metals. They can be considered to be a mixture of metal oxides; however, they can contain metal sulfides (also matte) and metal atoms in the elemental form. While slags are generally used as a waste removal mechanism in metal smelting, they can also serve other purposes, such as assisting in smelt temperature control and minimizing re-oxidation of the final liquid metal product before casting. The design of Ajaokuta Steel Company Limited is based on the Blast Furnace –Basic Oxygen Furnace (BF-BOF) process route for the production of iron and steel. In the production process of the blast furnace, molten iron and slag materials are produced. Molten iron will be transferred to the Steel Making Shop for the production of steel, while the slag materials produced can serve as spin off materials for industrial development. This paper therefore focus on the slag materials which is waste materials from smelting: (fused glassy material that is produced when a metal is separated from its ore during smelting). Some methods of processing slag materials for industrial development were discussed; the chemical compositions of slag from the blast furnace were brought to the fore. Applications and uses of slag materials were discussed with emphasis to the building, and construction industries .Slag can also be used as sound absorber in reducing noise and treating of industrial water. Some suggestions and recommendations were proffered for the use of slag materials for industrial development in Nigeria.
12:45 PM - D2.5
Syntheses and Characterization of CdSiO3 in Low Temperatures by Molten Salt.
Leonardo Santana 1 , Flávio Vichi 1 , Erick Souza 1
1 Fundamental Chemistry, USP, São Paulo, São Paulo, Brazil
Show AbstractIon-exchange reactions are used in the synthesis of many important materials. While these reactions are very well known in the gaseous and liquid states, they have received relatively little attention in the solid state. Recently, low temperature reactions have been studied as an alternative to conventional, energy-intensive processes. In this context, soft chemistry routes based on hydrothermal and microwave radiation have been proposed.An interesting alternative, which has not been as extensively explored as others, is the molten-salt synthesis, in which a molten salt flux acts either as a solvent or as a reactant. Cadmium metasilicate (CdSiO3) is an important matrix for use in devices having persistent luminescence, due to its good chemical and physical stability, ease of preparation, and low cost. Therefore, interest in this type of material has been increasing recently.1 Traditionally, cadmium metasilicate has been prepared by solid state synthesis, yielding pure, crystalline CdSiO3 at temperatures ranging from 900 – 1050 °C. However, these preparations involve long periods of ball-milling followed by long heating times, typically from 5 to 12 h. Moreover, materials prepared this way exhibit large highly aggregated particles.1Sol-gel routes, which involve the use of tetraethylorthosilicate (TEOS) as the silicon precursor, have also been proposed, but pure CdSiO3 is obtained in pure form only after heat treatments above 870 °C for several hours, also yielding large aggregated particles.In this contribution we report the successful preparation of single-phase CdSiO3 nanowires and nanorods at temperatures as low as 360 °C. Cadmium chloride and cadmium nitrate were used as a molten reactants. The resulting materials were characterized by x-ray diffraction (XRD), focused ion beam (FIB) microscopy, field-emission scanning electron microscopy (FESEM), surface area by nitrogen adsorption (BET). The characterization confirms the preparation of pure, single-phase, crystalline CdSiO3 nanoparticles in the form of nanowires and nanorods.1Qu, X.; Liu, W.; Su,G.;Qu, H.; Xu, C. J. Alloys Comp. 2009, 484, 641,644
D3: Nanomaterials/Composites
Session Chairs
Tuesday PM, November 29, 2011
Back Bay B (Sheraton)
2:30 PM - **D3.1
Making Composites without Matrix.
Ton Peijs 1
1 Centre for Materials Research, Queen Mary University of London, London United Kingdom
Show AbstractOver the last decennia mono-material concepts such as self-reinforced polymer composites based on oriented polymer fibres or tapes bonded together by a polymer of similar origin have emerged as promising new materials for lightweight structures with added ecological benefits due to their good recyclability. This presentation will report on recent developments in the field of self-reinforced polymer composites including systems based on PP, PE, PET, PLA, PPTA and cellulose. Next to environmental benefits as a result of their mono-material character which facilitates recyclability, and their lightness due to the replacement of (heavy) glass fibres by lightweight polymer fibres, these materials have also shown to exhibit competitive mechanical properties compared to their traditional counterparts. The main reason for their excellent mechanical properties is often the high reinforcement content in these types of composites. Since processing of these materials is based on non-traditional – non-impregnation based – processes their reinforcement content is not limited to the traditional 50-60 vol.%. Instead fibre volume fractions in these materials can often exceed 80-90 vol.% (and in some cases even 100%), giving them their advantageous mechanical characteristics.
3:00 PM - D3.2
Synthesis of Macroporous Calcium Carbonate/Magnetite Nanocomposites and Their Application in Photocatalytic Water Splitting.
Yi-Yeoun Kim 1 , Dominic Walsh 2 , Fiona Meldrum 1
1 School of Chemistry, University of Leeds, LEEDS United Kingdom, 2 School of Chemistry, University of Bristol, Bristol United Kingdom
Show AbstractWe report a simple and versatile method which concurrently achieves structural control and introduces functionality into CaCO3 microparticles. The work investigates the microwave-induced metamorphosis of highly hydrated calcium carbonate hexahydrate (ikaite) crystals incorporating microwave-absorbing superparamagnetic magnetite nanoparticles, and demonstrates that unique porous vaterite/magnetite composite crystals can be synthesised using this route. That the incorporporated nanoparticles are accessible and active for reactive processes is demonstrated through the exploitation of the magnetite nanoparticles/calcium carboante microparticles in photocatalytic water oxidation, where it is shown that they function as an effective, convenient and reusable material.Carboxymethyl dextran-magnetite (CMD-Mag) was prepared by a combined dextran carboxylation and magnetite precipitation reaction. Then, calcium carbonate was precipitated in a solution cooled to 0-3oC by precipitation of CaCl2 with (NH4)2CO3 in the presence of CMD-Mag nanoparticles. The precipitate was filtered cold before microwaving for 5 minutes. The magnetite cores of these particles were 1-4 nm in diameter and had a hydrodynamic diameter of 23 nm after coating with CMD. Coating with CMD stabilizes the particles in the crystal growth solutions and promotes absorption to the CaCO3 crystals, thereby facilitating encapsulation. The first phase precipitated in the presence of CMD-mag was amorphous calcium carbonate (ACC), which gradually transformed to CaCO3.6H2O crystals with hexagonal, plate-like morphologies in a cold water environment. Interestingly, magnetite incorporation significantly stabilized the CaCO3.6H2O crystals against crystallisation. Further, when these crystals were washed and then microwaved to dryness, their original morphologies were retained and Raman analysis and XRD showed them to be entirely polycrystalline vaterite. Imaging of these vaterite crystals showed that they displayed remarkable, open microstructures comprising 200 nm segregated columns formed from packed nanocrystals of vaterite, where the entire internal surface area of the porous CaCO3 particle is intimately associated with magnetite nanoparticles. BET measurements gave a surface area of 12.65 m2/g. In addition to the orange colour, the presence of Fe was quantified at 3.22 wt% using atomic absorption spectroscopy, which corresponds to 4.44 wt% magnetite and 9.87 wt% CMD-mag. The work additionally demonstrates that the Calcium carbonate/magnetite particles, due to Fe ion release, are effective in photocatalytic water oxidations that liberate O2. It is envisaged that this methodology is not unique to this CaCO3/magnetite system, but could be applied to the straightforward synthesis of a range of composites containing microwave absorbing nanoparticles. Further work is currently underway investigating alternative hydrated crystals and an extended range of microwave-active nanoparticles.
3:15 PM - D3.3
Characterization of an Ionically Cross-Linked Polymer-Clay Nanocomposite Prepared by Green, In Situ Melt Polymerisation of l,d-lactide by Stearate-Treated Layered Double Hydroxide.
Edward McCarthy 1 , Mauro Zammarano 2 1 , Gale Holmes 1 , John Howarter 1 , Yeon Kim 2 , Ryan Nieuwendaal 3 , David VanderHart 3 , Paul Maupin 4 , Paul Trulove 5 , Jeffrey Gilman 1
1 Sustainable Polymers Group, Polymer Division, Materials Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland, United States, 2 Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland, United States, 3 Electronics Materials Group, Polymer Division, Materials Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland, United States, 4 Office of Science, Department of Energy, Germantown, Maryland, United States, 5 Department of Chemistry, United States Naval Academy, Annapolis, Maryland, United States
Show AbstractAn organic-inorganic composite of poly(lactic acid), PLA, and magnesium aluminum stearate-intercalated layered double hydroxide, Mg Al LDH-St, has been produced by in-situ bulk polymerisation of l,d lactide monomer within nanolayers of Mg Al LDH-St without the use of an additional metal octanoate catalyst (e.g. tin) or solvent. An average polymer mass yield of 88% has been determined for the polymerisation, under an optimal clay loading of 5% LDH-St by mass.In this work we present thermogravimetric, spectroscopic and molecular mass data to investigate whether the formation of PLA is by co-ordination insertion ring-opening bulk polymerisation, (CIROP), catalysed principally and directly by layered double hydroxide at the clay surface, or by other competing mechanisms such as anionic polymerisation, (AROP), by free salts in the melt or polycondensation of hydrolysed lactide dimer facilitated by trace moisture. In addition, scanning electron microscope images of extract residues confirm the formation of an insoluble gel fraction within the composite suggesting cohesive ionic crosslinking between PLA and Mg Al LDH-St, strengthening the case for substantial CIROP at the clay surface. Solid state C-13 NMR and XPS characterization of the reaction components will also be presented.Lastly, initial rheology of the reaction product, as well as its soluble and insoluble gel polymer fractions obtained by methylene chloride extraction, is discussed to determine the extent of reinforcement provided by the gel fraction of the product.In the future it is intended to more fully characterise the nature of the integration between polymer and clay in terms of chemical bonding and molecular mass distribution as well as making further determinations of key mechanical properties using melt rheology and dynamic mechanical analysis.
3:30 PM - **D3.4
Design and Fabrication of Composite Nanostructures.
Hua Chun Zeng 1
1 , NUS, Singapore Singapore
Show AbstractDiscrete nanostructures have a limited scope of applications, due to the difficulty in separation and recovery after use. Furthermore, a functional nanostructure nowadays is normally not a single-phase solid, but a highly organized multicomponent materials system. To prepare composite nanostructures, architectural aspects of design and synthesis need to be addressed, because the ways of compositional and structural organizations in the final products will give profound impacts on their ultimate performance. Therefore, our current research efforts are mostly directed to chemical methods for self-assembly of functional materials into complex nanostructures, which will be the subject of this presentation. We have recently synthesized a range of functional nanostructures with architectural designs. In these syntheses, most processing steps were carried out in liquid media under mild reaction conditions.1-7 Similar to organic synthesis, for example, various kinds of organic ligands, surfactants and inorganic/organic salts were utilized in our experiments in order to create steric hindrance effects, binding interactions, and control of surface reactivity for directional growth and organization of nanomaterials.1-7 Therefore, unlike solid-solid or gas-solid reactions, synthetic processes and assemblies conducted in solution media would then be analogous to the conventional total synthesis of organic molecules.1 In our research, preparative processes, size manipulation, surface functionalization, catalytic reactions, and reactivation of nanoparticles inside the nanostructures are being investigated. To make composite nanostructures usable in real reaction environments, for instance, new processing schemes for complex nanostructures with permanent engagement among primary building units have been developed. Tiered organizations among different components have also been addressed in several model systems, including architecture of interior space. These highly organized nanostructures have shown promising performances in some new applications.References1. H.C. Zeng, Journal of Materials Chemistry, 21 (2011) 7511–7526. 2. T.T. Chng, L. Polavarapu, Q.H. Xu, W. Ji and H.C. Zeng, Langmuir, 27 (2011) 5633–5643.3. C.C. Li and H.C. Zeng, Journal of Materials Chemistry, 20 (2010) 9187-9192. 4. M.L. Pang, J.Y. Hu and H.C. Zeng, Journal of the American Chemical Society, 132 (2010) 10771-10785. 5. K.X. Yao, X.M. Yin, T.H. Wang and H.C. Zeng, Journal of the American Chemical Society, 132 (2010) 6131-6144.6. M.L. Pang and H.C. Zeng, Langmuir, 26 (2010) 5963-5970.7. S.M. Zhang and H.C. Zeng, Chemistry of Materials, 22 (2010) 1282-1284.
D4: Nanomaterials/Metals
Session Chairs
Tuesday PM, November 29, 2011
Back Bay B (Sheraton)
4:30 PM - D4.1
Syntheses of Metal Nanoparticles in Ionic Liquids.
Silke Behrens 1 , Sarah Essig 1
1 , Karlsruhe Institute of Technology, Karlsruhe Germany
Show AbstractRecently, room-temperature ionic liquids have attracted great interest, e.g. as reaction medium, reactant or template for the synthesis of inorganic nanomaterials. Ionic liquids are molten organic salts with low melting points (<100°C). They are well known for their low vapor pressure, good thermal stability, and high polarity. Their physico-chemical properties such as viscosity, vapor pressure, polarity, and solvent miscibility may be further adjusted by choice of the cation, anion and by the length of the lateral alkyl side chains of the hetercyclic ring. Hence, ionic liquids offer an interesting combination of novel properties that enlarge the possibilities of classic nanomaterial synthesis. Ionic liquids are shown to provide a favorable environment for the synthesis of magnetic metal nanoparticles without adding any further stabilizing ligands. The nature of the applied ionic liquid influences nanoparticle nucleation and growth and may be recycled after synthesis. Herein, we describe a simple and “green” method for the synthesis and tailoring of nanoparticle-based magnetic fluids in divers carrier liquids.
4:45 PM - D4.2
One-Step Synthesis of Stable Metallic Nanoparticles on Eco-Friendly Ionic Liquids.
Anantha No LAST NAME 1 , Wang Xiu 1 , Chee Cheong Wong 1
1 School of Materials Science & Engineering , Nanyang Technological University, Singapore Singapore
Show AbstractMetallic nanoparticles are more often obtained by chemical - decomposition or reactive techniques, involving the extensive usage of harmful reducing or stabilizing agents. A facile green synthesis technique resulting in readily exploitable nanoparticle dispersion in ionic liquid without the use of any additional agents is reported here. 1-Propyl- 3- Methyl Imidazolium Iodide (PMIM-I) is a non-volatile, thermally stable and non-toxic ionic liquid. This eco-friendly liquid is used as the substrate for thermal evaporation of gold to obtain stable gold nanoparticles. On being examined by Transmission Electron Microscopy and Ultraviolet-Visible spectroscope the high monodispersity in their sizes was revealed. The byproduct free, ‘clean’ processing technique helps in obtaining un-contaminated particles. The thermal evaporation method used (for the generation of metallic vapor) plays a significant role in the difference in kinetics of the formation and growth of nanoparticles, unlike the widely reported sputtering technique for vapor generation. The formed particles are deposited only on the top surface of the liquid as observed through optical microscope, leaving the bulk of the liquid devoid of any particles. Thus the nucleation and growth of the particles is said to have occurred by surface diffusion process only. Further experimental investigations carried out for varied viscosities of ionic liquids under diverse levels of supersaturations were in agreement with the primary observation. A deeper investigation into the formation kinetics has the potential application for synthesizing other nanomaterials via this environmental friendly, straightforward approach without polluting the surroundings with toxic reagents.
5:00 PM - D4.3
Facile One-Step Synthesis of Alloyed/Core-Shell Pd/Pt Nanoparticle Assembles by Tri-Block Copolymers.
Fang-ching Chang 1 2 , Yen-Cheng Li 1 , Ren-Jye Wu 1 , Chun-Hua Chen 2
1 Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu Taiwan, 2 Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu Taiwan
Show AbstractThe morphology of nanoparticles is one of the most critical issues to the performance of catalysts. In this work, a one-step synthesis of a series of morphologically-controlled Pd and Pd/Pt nanoparticle assembles has been newly designed and achieved by reducing PdCl2 and H2PtCl6 reagents in aqueous Pluronic F127 (polypropylene oxide-polyethylene oxide-polypropylene oxide triblock copolymer, PEO99PPO69PEO99) gels with the appearance or absence of L-ascorbic acid (AA). The F127 acts as not only a reductant, but most importantly, a tunable nanoreactor since the high-concentration F127 (30 wt%) spontaneously leads a face-center-cubic packing of spherical micelles, consisting of a relatively compact PPO core and a well solvated PEO shell, at room temperature. It has been found that the well assembled F127 micelles indeed contribute the extremely uninform aggregated morphologies observed and AA seems to affect the reduction locations, i.e. the PEO shells within micelles or spaces between micelles. The further fine structure of the formed nanoparticle assembles were qualitatively and quantitatively characterized by x-ray diffraction, small-angle x-ray scattering, transmission electron microscopy and UV-vis spectra. In addition, the catalytic performance of the synthesized Pd and Pt/Pd nanoparticle assembles will also be discussed.
5:15 PM - D4.4
One Pot Synthesis of Gold NanoNachos for Biotechnological Applications.
Beatriz Pelaz 1 , Pablo del Pino 1 , Valeria Grazu 1 , Wolfgang Parak 2 , Jesus de la Fuente 1
1 Instituto de Nanociencia de Aragon, University of Zaragoza, Zaragoza, Zaragoza, Spain, 2 , University of Marburg, Marburg Germany
Show AbstractIn the last years, gold nanoparticles have found a great deal of interest in the area of nanoscience. This is due to the interesting physicochemical properties that these materials bear including biocompatibility, localized surface plasmons or ease of biofunctionalization by means of molecules bearing thiol groups. More recently, asymmetric gold nanoparticles (NPs) such as nanorods, triangular nanoprisms or core-shell dielectric-gold NPs have achieved an increasing popularity. This trend is mainly originated from the absorption band that they present in the NIR range of the electromagnetic spectrum; NIR excitation of NPs is the most favorable scenario for biomedical applications since NIR radiation has a suitable penetration depth in biological tissues. Upon excitation with NIR radiation, these asymmetric materials can release heat to their most immediate vicinity. However, most of the methods to produce NIR absorbing Au NPs relies on challenging synthesis with several steps and/or seed-mediated approaches with cetyltrimethylammonium bromide (CTAB) as a surfactant. To the best of our knowledge, CTAB is the most widely used and convenient surfactant to synthesize Au nanorods and nanoprisms although it is a well-known toxic cationic surfactant. The development of straightforward and scalable synthesis methods of non-cytotoxic Au anisotropic NPs is of the most importance.Here we describe a simple and straightforward synthesis route to produce gold triangular nanoprisms that we have called NanoNachos (NNs) due to the characteristic shape they present. While keeping the thickness of NNs constant, the edge length and therefore the aspect ratio can be varied by adjusting the final concentration/molar ratio of gold salt and reducing agent. Thus, the LSPR of NNs can be tuned along the NIR range. In contrast to most of the previously reported methods to produce Au nanoprisms in high yield, CTAB is not required in our method. The feasibility of NNs as transducers for photothermal therapy is proven at the single cell level. Besides the simplicity of the synthesis method, avoiding CTAB makes NNs very interesting probes for applications in nanomedicine.
5:30 PM - D4.5
Synthesis of Dendrimer-Stabilized Gold Nanoparticles Using Green Methods.
Oscar Olea-Mejia 1 , Alfredo Vilchis-Nestor 1 , Marco Camacho-Lopez 2 , Oscar Olea-Cardoso 3 , Jimena Hernandez-Cejudo 1
1 Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM. Facultad de Química, Universidad Autónoma del Estado de México, Toluca, Mexico, Mexico, 2 Laboratorio de Investigación y Desarrollo de Materiales Avanzados. Facultad de Química, Universidad Autónoma del Estado de México, Toluca, México, Mexico, 3 Facultad de Química, Universidad Autónoma del Estado de México, Toluca, Mexico, Mexico
Show AbstractGold nanoparticles were successfully obtained using two different green methods. The first one was the laser ablation of a gold rod immersed in a liquid; the second was the reduction of a metallic salt using a natural bioreductor. These techniques were carried out in a dendrimer solution in order to control the shape and size of the nanoparticles as well as for their stabilization. Our samples were characterized by UV-Vis spectroscopy and by Transmission Electron Spectroscopy (TEM). It was observed that without dendrimer it is possible to obtain nanoparticles with an average size of around 10 nm depending on the method used. We have seen an effect of the concentration and the type of dendrimer used in the properties of the particles. When adding dendrimer to the system, it is possible to reduce the particle size up to 3 nm as well as narrow their size distribution. The particle shape is also affected by the dendrimer since more homogeneous spherical nanoparticles are formed. Some of the nanoparticle colloidal solutions are stable for a few weeks while other precipitate a few days after the synthesis.
5:45 PM - D4.6
Size Tunable Continuous Ultrasonic Sonoelectrodeposition of Submicron Metallic Particles.
Joseph Reneker 1 , Taofang Zeng 1
1 Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
Show AbstractTypical ultrasonic sonoelectrodeposition particle synthesis methods use out of phase pulses of electric current and ultrasound pulses. In this technique, a current pulse deposits particles on a surface, which are subsequently removed with a burst of ultrasonic energy. Such out of phase methods preclude potentially useful processes which occur under simultaneous application of ultrasonic and electric energy. We have studied metallic particles electrodeposited under continuous ultrasonic irradiation. Results have indicated a mechanism for particle growth that is not present in conventional out of phase pulsed electrodeposition. The effect of this mechanism on the size distribution of electrodeposited particles was studied. A continuous sonoelectrodeposition reactor design is proposed to take advantage of this growth mechanism to enable size tunable synthesis of submicron particles. This technique should be applicable to the wide variety of particles already synthesized by pulsed sonoelectrodeposition. As in conventional commercial electroplating, electrolyte solutions can be reusable. This is an affordable and environmentally friendly method for producing bulk quantities of submicron nanostructured particles.
Symposium Organizers
" " " Brookhaven National Laboratory
Mato Knez Max Planck Institute of Microstructure Physics
Stanislaus S. Wong State University of New York at Stony Brook
Hongjin Fan Nanyang Technological University
Woo Lee Korea Research Institute of Standards and Science (KRISS)
D9: Poster Session: Sustainable Synthesis, Characterization, and Application
Session Chairs
Mato Knez
Woo Lee
Stanislaus Wong
Wednesday PM, November 30, 2011
Exhibition Hall C (Hynes)
D5: Nanomaterials/Catalysts
Session Chairs
Wednesday PM, November 30, 2011
Back Bay B (Sheraton)
9:30 AM - **D5.1
Synthesis of Nanostructured Catalysts for Biomass Conversion.
Christopher Marshall 1 , Eric Stach 2 , Fabio Ribeiro 2 , Jeffrey Greeley 1 , Justin Notestein 3 , Kenneth Poeppelmeier 1 3 , Larry Curtiss 1 , Mayfair Kung 3 , Peter Stair 1 3 , Randy Winans 1 , SonBinh Nguyn 3 , Jeffrey Elam 1
1 Energy Systems Division, Argonne National Laboratory, Argonne, Illinois, United States, 2 , Purdue University, West Lafayette, Indiana, United States, 3 , Northwestern University, Evanston, Illinois, United States
Show AbstractThe successful transition to an energy economy based on biomass will require radical advances in catalyst science. This challenge demands a new paradigm in catalyst synthesis whereby inorganic components can be assembled at the atomic scale to yield complex, multifunctional catalysts rivaling Nature’s enzymes in their specificity. To this end, we have developed a novel approach combining templated synthesis for shape-selectivity with the atomically-precise positioning of discrete functionalities. In this approach we begin with a supporting scaffold for catalyst growth upon which we chemically attach molecular templates. Next, atomic layer deposition is used to build a structure around each template in an atomically precise, layer-by-layer fashion where the thickness and composition can be tuned at each layer. Finally, the template is removed yielding a “nanobowl” defining a structured catalytic environment. The molecular template can be synthesized to contain bulky organic ligands surrounding a catalytic atom or cluster which remains anchored to the bottom of the bowl after ligand removal. Furthermore, one or more layers in the bowl wall can be selected to serve as a co-catalyst (e.g. Lewis acid group) positioned at a well-defined distance from the catalyst at the bottom of the bowl. This presentation will review our recent progress synthesizing, characterizing, modeling, and testing these unique catalytic materials.
10:00 AM - D5.2
Shape-Controllable Synthesis and Facet-Dependent Catalytic Property of Platinum Alloy Nanoparticles.
Jianbo Wu 1 , Rajinder Singh 1 , Miao Shi 1 , Isthier Chaudhury 1 , Hong Yang 1
1 Chemical Engineering, University of Rochester, Rochester, New York, United States
Show AbstractSince the surface structure of metal alloy nanocrystals plays an important role in catalytic activity and selectivity, shape-controlled synthesis of metal alloy nanostructures has attracted increasing attention owing to their potential use as highly active heterogeneous catalysts in fuel cells, batteries, and other alternative energy systems. However, the shapes controlled by the current methodologies are limited by and heavily relied on the materials. Recently, we report a series of shape-controlled Pt-M alloy nanocrystals with a wide range of compositions via a versatile synthetic approach under the same CO-assisted reduction condition [1]. Among them, {111} faceted octahedron shows 50% higher in oxygen reduction specific activity over {100} faceted cubes for Pt3Ni systems [1-2]. In this presentation, I will discuss the selectivity of binding of CO between {111} and {100} Pt surfaces. Furthermore, a newly developed monodisperse shape with highly twinned planes has also been obtained. An oxygen reduction reaction (ORR) specific activity of highly twinned facets is observed. Surface treatment instead of annealing will also be discussed to illustrate the need for proper activation of the catalysts made in solution phase.References:[1] Wu, J.; Gross, A.; Yang, H., Shape and Composition-Controlled Platinum Alloy Nanocrystals Using Carbon Monoxide as Reducing Agent, Nano Lett. 2011, 11, 798-802.[2] Wu, J.; Zhang, J.; Peng, Z.; Yang, S.; Wagner, F. T.; Yang, H., Truncated octahedral Pt3Ni oxygen reduction reaction electrocatalysts, J. Am. Chem. Soc. 2010, 132, 4984–4985.
10:15 AM - D5.3
Remarkable Effect of Bimetallic Ni-Ru Catalysts in Dehydrogenation of Ammonia Borane.
Guozhu Chen 1 , Stefano Desinan 1 , Renzo Rosei 2 , Federico Rosei 1 , Dongling Ma 1
1 Institut National de la Recherche Scientifique, Quebec university, Varennes, Quebec, Canada, 2 Physics Department, Trieste University, Via Valerio Italy
Show Abstract Bimetallic nanoparticles (NPs) exhibit promising properties, quite distinct from those of their monometallic counterparts. However, the synthesis and hence the realization of desirable properties of these bimetallic structures are still quite challenging since their structure and composition are influenced by many parameters. It is thus of interest to rationally design these NPs, to identify appropriate synthetic routes to achieve controlled synthesis, and furthermore to gain full knowledge of their structure and composition in order to realize their high potential. Herein, we report, for the first time, the synthesis of Ni@Ru core-shell NPs using a wet-chemistry method. [1] The structure was thoroughly investigated using an array of characterization tools. The Ni@Ru NPs show remarkable performance in the hydrolysis of amonia borane. Their catalytic activity outperforms recently reported bimetallic catalysts in terms of the turnover frequency, including those based on the most active noble metals, such as platinum. The high catalytic activity is mainly attributed to the high surface area owing to the presence of many tiny 2-3 nm Ru NPs on the surface of Ni; the synergistic effect between Ni and Ru also cannot be excluded. Moreover, Ni@Ru NPs show a saturation magnetization and weak hysteresis similar to those of Ni NPs, indicating they basically remain the superparamagnetic behavior of the Ni core. Our recent results on the synthesis of novel Ni-Ru alloy NPs and their interesting catalytic properties will also be presented. References:[1]. Chem. Commun., 2011, 47, 6308-6310
10:30 AM - D5.4
Nanoscale β-Sn1−nWO4●nSn(hp) – A Highly Efficient Daylight-Driven Photocatalyst.
Jan Ungelenk 1 , Claus Feldmann 1
1 Inorganic Chemistry, Karlsruhe Institute of Technology, Karlsruhe Germany
Show AbstractPhotocatalysis is a powerful technology for water treatment including decomposing organic pollutants and crucifying germs. However, the standard material TiO2 is limited to UV-light whereas many visible-light-sensitive photocatalysts contain harmful (e.g. BiVO4) or high-cost elements (e.g. InNbO4) [1, 2]. Considering this, β-SnWO4 – the bright-yellow high temperature phase of SnWO4 – appears much more suitable. Both theoretical considerations as well as tests on bulk material indicate promising good photocatalytic properties [3, 4]. Yet, β-SnWO4 has not been available on the nanoscale.Here, we report on bright-yellow tin tungstate-based nanoparticles that are able to degrade various organic dyes 5 - 10 times faster under simulated daylight than commercially available TiO2 (Degussa P25) [5]. Moreover, the material works more efficient than BiVO4, the most important visible-light-sensitive photocatalyst to date. The nanomaterial is easily obtained via quick nucleation from aqueous solutions utilizing efficient electrostatic stabilization. Conducted at ambient temperature, the reaction yields a remarkably, self-adjusting phase composition of incipient crystalline yellow β-SnWO4 nanoparticles containing a certain amount of the cubic high-pressure phase of tin: Sn(hp). The presence of elemental tin might be beneficial with concern to the photocatalytic properties, supposably by providing an efficient charge separation. Diverse organic dyes including phenothiazine dye methylene blue, triphenylmethane dye basic green 4 and azo-dye methyl red are decomposed rapidly. The nanoparticles exhibit an average diameter of 20 nm, a low degree of agglomeration and a high specific surface (71 m2/g). Recycling experiments proved phase stability and reusability. Notably the presented preparation is both low-cost and truly sustainable since it is energy saving and can be done without any toxic elements, organic solvents or additives. As the chosen model organic dyes are classified as hazardous to water and to health, the detoxification potential of β-Sn1−nWO4●nSn(hp) becomes obvious.[1] A. Fujishima, X. Zhang, D. A. Tryk, Surf. Sci. Rep. 2008, 63, 515 (Review).[2] H. Goesmann, C. Feldmann, Angew. Chem. Int. Ed. 2010, 49, 1362 (Review).[3] A. Walsh, Y. Yan, M. N. Huda, M. M. Al-Jassim, S. H. Wei, Chem. Mater. 2009, 21, 547.[4] I. S. Cho, C. H. Kwak, D. W. Kim, S. Lee, K. S. Hong, J. Phys. Chem. C 2009, 113, 10647.[5] J. Ungelenk, C. Feldmann, Appl. Catal. B 2011, 102, 515.
10:45 AM - D5.5
Characterization of Nano-Crystalline Structure of TiO2 Supported Manganese Oxide Catalysts by Raman Spectroscopy: Correlation between Structure and Catalytic Activity.
Sergey Mamedov 1 , Padmanabha Reddy Ettireddy 2 , Punit Boolchand 3 , Panagiotis Smirniotis 4
1 , Horiba Jobin Yvon Inc., Edison, New Jersey, United States, 2 , Cummins Emission Solutions , Columbus, Indiana, United States, 3 School of Electronics and Computings Systems, University of Cincinnati, Cincinnati, Ohio, United States, 4 College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio, United States
Show AbstractA series of TiO2 supported manganese oxide catalysts were studies by Raman spectroscopy. Materials were prepared by wet-impregnation method and selective catalytic reduction (SCR) of NO was measured for materials studied. Raman spectra of catalysts as well as manganese oxides are presented. It was found that there is strong correlation of the position and the width of E2g mode of anatase at 146 cm-1 and Mn-oxide(s) concentration. The Mn/TiO2 samples show that this peak gradually decreases in intensity becomes broader and shifts to the high frequency region with increase of Mn loading and disappeared at the concentration of Mn-oxide above 11%. At low loading, Mn-oxide forms monolayer structures with Mn atoms incorporated to the crystalline lattice. At concentrations above 11%, Mn-oxide forms microcrystalline species. The position and broadening of the peak can be described by the optical confinement model that depends on the size of the nano-crystals. A strong correlation between the shape of E2g mode and catalytic activity was found.
D6: Materials for Energy Production and Storage
Session Chairs
Wednesday PM, November 30, 2011
Back Bay B (Sheraton)
11:30 AM - **D6.1
Low-Temperature Carbon Materials for Energy Storage Processes.
Robert Schloegl 1
1 Inorganic Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Berlin, Germany
Show AbstractThe enhanced utilization of renewable energy with its main component of primary electricity calls for large-scale solution to store the energy for various time scales. Besides thermo mechanical solutions and batteries the conversion of electricity into chemical fuels is of relevance when no shadow fossil fuel solutions are availableElectrolysis of water is a scalable solution provided that we solve the challenges of excess overpotential, of using noble metal electrocatalysts and of limited stability during intermittent operation.The contribution lists some of the origins of these shortcomings using model experiments with Pt single crystals. Then we discuss the possibility to use carbon as electrode material without adding noble metals. We report on the combination of carbon nanotube supports with Mn-oxide nanoparticles as oxygen evolution electrodes and review the possibilities to generate carbon materials with suitable stability against oxygen attack. The strategy towards these materials starts from nitrogen-containing organic precursors and uses a combination of hydrothermal and medium-temperature thermal treatments to arrive at suitable carbon materials without going through graphitization steps. The possibility to use these novel carbon materials also in battery applications will be discussed.
12:00 PM - D6.2
Electrospinning Synthesis of LiFePO4 Nanowires and Corresponding Electrochemical Activity in Li-Ion Battery.
Junjie Niu 1 2 , Akihiro Kushima 1 2 , Liang Qi 1 2 , Jian Yu Huang 3 , Ju Li 1 2
1 Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2 Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States, 3 Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico, United States
Show AbstractOne-dimensional LiFePO4 nanomaterials have the potential of fast charging, high power-density and high chemical stability, which are necessary for portable devices like laptop and cell phone. It has been shown that LiFePO4-C is an intrinsically safer cathode material than the commercial LiCoO2 and manganese spinel. However, as an olivine structure, lithium iron phosphate nanowires are difficult to form via regular physical or chemical method. In our previous work, we haved reported a nanoscale electrochemical device—consisting of a single tin dioxide nanowire anode, an ionic liquid electrolyte, and a bulk lithium cobalt dioxide cathode—and the in situ observation of the lithiation of the SnO2 nanowire during electrochemical charging using transmission electron microscope (TEM) (Jian Yu Huang et al. Science 330, 1515-1520 (2010)). In current work, large scales of LiFePO4 nanowires were synthesized using an electrospinning method. LiC2H3O2.2H2O, Fe(NO3)3.9H2O, H3PO4 and poly acrylic acid (MW:240000) were used as chemical reagents and a high voltage of 18-25 kV was applied to obtain the nanowires. A poly-crystal LiFePO4 with a small amount of carbon was received. The carbonated carbon inside assisted the formation of nanowires and also will improve the electrochemical performance. The treated nanowires were used for charging/discharging test under in-situ TEM. The lithiation/delithiation process along the nanowire was well analyzed.
12:15 PM - D6.3
Aluminum-Ion Batteries with Excellent Cycle Life and Improved Performance.
Jayaprakash Navaneedhakrishnan 1 , Lynden Archer 1
1 , Cornell University, Ithaca, New York, United States
Show AbstractWe have designed a novel Al-ion battery with excellent cycle life and improved capacity ever reported in the literature. The battery system works with an ionic liquid based electrolyte containing Al salt. When calculated, the battery delivered a discharge capacity more than 300 mAh/g, with a very stable cycle performance. Since the system exploits aluminum or aluminum intercalation/deintercalation compounds as electrodes, it has many advantages over the conventional Li-ion system. Also, Al-ion system has very high energy density and economically viable status due to the surplus availability of the metal. We have also studied the intercalation deintercalation behavior of various metal oxides against aluminum anode and derived a suitable metal oxide with enhanced electrochemical performance. Various reasons for the improved cycle life will be discussed in detail with experimental evidences.
12:30 PM - D6.4
Synthesis, Characterization, and Supercapacitor Application of RuO2 and Graphene-RuO2 Nanocomposite Materials.
Mohamad Khawaja 1 , Manoj Ram 2 3 , Farah Alvi 3 , Yogi Goswami 1 , Ashok Kumar 2 3 , Elias Stefanakos 1
1 Center for Clean Energy, University of South Flrodai, Tampa, Florida, United States, 2 Nanotechnology Education and Research Center, University of South Florida, Tampa, Florida, United States, 3 Mechanical Engineering, University of South Florida, Tampa, Florida, United States
Show AbstractElectrochemical supercapacitor has high energy density with an excellent reversibility, and is operated at greater specific power than most rechargeable batteries. Therefore, research has been focused on improving the novel materials and methods to enhance the operation of supercapacitors. Activated carbon metal oxides (ruthenium oxide ‘RuO2’, MnO2) take advantage over conducting polymers for their stability. Mixing conducting polymers and metal oxides has recently been investigated to understand the behavior and stability of the hybrid supercapacitor. This research project focuses on supercapacitor electrodes coated with RuO2 and graphene (G)-RuO2 synthesized materials.The G-RuO2 and RuO2 nanomaterials were synthesized using sol-gel technique. Besides, the commercially obtained ruthenium oxide was used for comparison purposes. The RuO2 and G-RuO2 materials were characterized using electrochemistry, Scanning Electron Microscopy (SEM), Raman spectroscopy, X-ray-diffraction, and Transmission Electron Microscopy (TEM) techniques. The synthesized G-RuO2 and RuO2 powder and the commercial RuO2 were mixed with Nafion and coated on graphite electrodes. The cyclic voltammogram, charging-discharging, stability, and life cycle of the various RuO2 and G-RuO2 materials were studied in supercapacitor configurations. This study provides a fundamental understanding for high performance synthesized RuO2 as well as G-RuO2 material. The high specific capacitance and stable charging –discharging cycles have been observed in G-RuO2 containing equal ratio of graphene to RuO2. This study provides a fundamental understanding of supercapacitor applications for high performance synthesized RuO2 and G-RuO2 nanoparticles. Based on experimental data shown in this work, we believe that G-RuO2 supercapacitor technology could be viable for commercial applications.
12:45 PM - D6.5
Influence of the Index Metallic Salts - Complexing Agent in a Sol-Gel Process to Obtain Nanoscaled Zirconium Substituted Yttrium (YSZ) to Electrolyte Application in Solid Oxide Fuel Cell (SOFC).
Rene Cienfuegos Pelaes 1 2 , Alejandro Ehecatl Correa Ceron 3 , Ramona Alicia Salazar de Leon 3 , Leonardo Chavez Guerrero 1 2 , Sugeheidy Carranza Bernal 1 , Moises Hinojosa Rivera 1 2
1 Materiales, Facultad de Ingenieria Mecanica Electrica, San Nicolas de los Garza, Nuevo Leon, Mexico, 2 Advanced Materials, Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, Apodaca, Nuevo Leon, Mexico, 3 Ciencias químicas, Facultad de Ciencias Químicas, San Nicolas de los Garza, Nuevo Leon, Mexico
Show AbstractThe objective of the present study is to obtain the electrolyte material YSZ a low cost via sol gel through exploration of the index rate between the complexing agents and the metallic salts (HMTA / metallic salts) from 1 to 5 prepared by a polymeric way in a sol gel process. We show an easy method that could be used in the industrial scale in order to obtain solid electrolyte material for its application in SOFC to operate at temperatures in the range of 700 800°C. The zirconium substituted to 8% of yttrium (CYSZ= 0.2 mol*L-1 metallic salts concentration-) having as reference the papers from Lenormand and Rieu. The presence of the phase in the materials has been confirmed by X-ray diffraction assisted by thermal analysis tests , for indexes from 2 to 5 at a temperature of 1000°C for 5 hours at a calcination rate (from amorphous dust obtained at 400°C) of 1000°C per hour. The grain average size for crystalline powder has an average near 50 nm and standard deviation close to 9 nm, it was confirmed by scanning electron microscope (SEM).
D7: Sustainable and Energy-Efficient Synthesis I
Session Chairs
Wednesday PM, November 30, 2011
Back Bay B (Sheraton)
2:30 PM - **D7.1
Solution-Based Vapor Deposition of Green Materials: Oxides and Organic Thin Films and Nanomaterials.
Shizuo Fujita 1 , Kentaro Kaneko 1 2 , Takumi Ikenoue 1 2 , Hiroshi Ito 1 , Takuto Igawa 1 , Jinchun Piao 1 2 , Sam-Dong Lee 1 2 , Shigetaka Katori 2
1 Photonics and Electronics Science and Engineering Center , Kyoto University, Kyoto Japan, 2 Department of Electronic Science and Engineering, Kyoto University, Kyoto Japan
Show AbstractThe increasing needs for "green materials", that is, stable and environmental-friendly materials together with unique functions, have encouraged us to develop novel oxide and organic semiconducting thin films and nanomaterials. The progress of "green chemistry", with which we can reduce the energy required for materials fabrication is important for the enhanced propagation of new devices at low cost. Interestingly, oxide semiconductors can potentially be grown by non-vacuum-based simple technologies through "green chemistry", because oxygen is not an impurity and no maximum care to remove oxide impurities may be essential. For organic semiconductors, solution-based "green chemistry" such as ink-jet printing, spin-coating, and spray-coating has already been developed for certain materials, but a new technology has always been required for the effective use. The combination of "green materials" and "green chemistry" is an essential issue in order to support the environmental-friendly economical development in our planet.As an oxide semiconductor, focused researches have been carried out for ZnO. In addition, we pay attention to various oxides because oxide semiconductors possess a variety of functions. For the growth of oxide semiconductors through "green chemistry", we have developed the ultrasonic-spray mist chemical vapor deposition technique, where safe and inexpensive liquids are used as source and they are atomized by ultrasonic so that their mist particles are transferred by carrier gas into the heated reaction area. This has successfully been applied to amorphous, polycrystalline, and single-crystalline semiconductors. Increasing demands for ZnO transparent electrodes have been satisfied with this technique. Layer-by-layer growth of single-crystalline ZnO, together with its reasonable electrical properties, has also been succeeded. Recently, we showed the growth of corundum-structured Ga2O3 on sapphire substrate, followed by (GaFe)2O3 alloys exhibiting ferromagnetic properties, suggesting future application as spintronic materials. Other oxides investigated include SnO2, Cr2O3, V2O3, Fe3O4, and LiMn2O4.The mist-based deposition technology has also been applied to organic materials. We have showed the deposition of an electroluminescent material, aluminum tris(8-hydroxyquinoline) (Alq3), a conductive polymer, PEDOT:PSS, and so on. These materials have generally been deposited by vacuum evaporation or spin-coating, but with the mist-based technology we can eliminate the vacuum process (compared to vacuum evaporation), perform uniform deposition with precise thickness control (compared to spin-coating), and reduce the wastes of source materials. Applications to fabricate solar-cells and light-emitters are also in progress.
3:00 PM - D7.2
Sustainable Synthesis of Semiconductor Nanoparticles in a Continuous Flow Reactor.
Daniel Ness 1 2 , Jan Niehaus 1 , Huong Tran 2 , Horst Weller 1 2
1 , CAN Hamburg, Hamburg Germany, 2 Physical Chemistry, University of Hamburg, Hamburg Germany
Show AbstractMaterials in the nanoscale range have gained tremendous interest not only in research areas but also in industry over the past twenty years. Their special properties arising from size-dependent attributes and a great variety in material composition have shown to be valuable in a range of different applications.[1] Within this paper we present a system which is capable of the sustainable and continuous production of fluorescent nanoparticles (NP).
Cd-based fluorescent NPs – Quantum Dots (QDs) - in particular found a great acceptance in processes for monitoring and targeting, e.g. in light emitting devices or lasers[2] as well as marker for biological systems like proteins or DNA.[3] For this reason methods for protective coating of the more or less instable core (CdSe) have been developed leading to structures with CdS, ZnS or CdS/ZnS as shell components among others.[4]
Because of their widespread use in research as well as industry a sustainable synthetic method is essential to guarantee consistent properties over time without losing the ability to customize the particles as required. The common strategy for the synthesis of QDs is based on a batch process called hot-injection method.[5] This procedure requires high nucleation temperature, a fast cooling step to the growth temperature and immediate and complete mixing after the injection. Up-scaling the synthesis is difficult in this manner and leads to slightly different properties each time the reaction has been performed.
This issue can be addressed by performing the synthesis in a continuous flow reactor.[6] Combining the utilization needs with the features of such a technical system for the production of NPs gives some crucial advantages over the common batch synthesis:
- reaction conditions can simply be modified and adjusted
- easy optimization of particle systems by rapid screening of parameters
- avoiding wastage of expensive materials and time
- high reproducibility of NP properties
- online quality control by integrated spectroscopic units
- enhancement of production even to the kg-scale possible
The perceptions obtained from over 20 years of excessive research in the area of light-emitting NPs has been considered in the design of this system. Therefore it is possible to synthesize simple CdSe core particles as well as core-shell like structures.
[1] A. P. Alivisatos, Science 1996, 271, 933-937.
[2] R. Xie et al., J. Am. Chem. Soc. 2005, 127, 7480-7488.
[3] R. Jin, Angew. Chem. 2008, 180, 6852-6855.
[4] P. Reiss et al., Small 2009, 5, No. 2, 154–168.
[5] H. Weller et al., J. Phys. Chem. B 2003, 107, 7454-7462.
[6] B. K. H. Yen et al., Adv. Mater. 2003, 15, 1858-1862.
3:15 PM - D7.3
Sustainable Synthesis of Nanowires at Low-Temperature from Aqueous Solutions Driven by Screw Dislocations.
Fei Meng 1 , Linsen Li 1 , Salih Hacialioglu 1 , Song Jin 1
1 Chemistry, University of Wisconsin Madison, Madison, Wisconsin, United States
Show AbstractVapor-Liquid-Solid (VLS) growth and analogous catalyst-driven mechanisms almost exclusively explain modern nanowire (NW) growth. Such synthesis require catalysts which are usually noble metal nanoparticles, and are often conducted in high vacuum and high temperature environments that inevitably increase the cost and energy consumption of the NW production. We have recently reported a new catalyst-free and template-free NW growth mechanism in which axial screw dislocations provide self-perpetuating steps to enable one-dimensional crystal growth. This growth mechanism can be operated in either vapor or solution phase, the latter of which is intrinsically more scalable and less costly than the former. We have shown a variety of different materials such as zinc oxide (ZnO), iron oxides/hydroxides, cuprous oxide (Cu2O) and copper (Cu) can be synthesized into NW morphology in low-temperature aqueous solutions via this growth mechanism. The key to promote the dislocation-driven growth is maintaining a constant low precursor supersaturation, which is achieved using a continuous flow reactor (CFR). Furthermore, we design a close-loop CFR where the unreacted precursors can be recycled and reused to equilibrium concentration, therefore making the synthesis more cost- and chemical-efficient. We believe that the continuous solution synthesis may ultimately become the most inexpensive, chemical- and energy-efficient large-scale synthetic method for practically manufacturing NWs for large-scale applications.
3:30 PM - D7.4
Metal-Catalyzed, Energy-Efficient Growth of Crystalline Semiconductor Nanodots, Nanowires and Thin Films at Temperatures below 180°C.
Zumin Wang 1 , Lars Jeurgens 1 , Fritz Phillipp 1 , Eric Mittemeijer 1
1 , Max Planck Institute for Intelligent Systems, Stuttgart Germany
Show AbstractCrystalline semiconductor nanostructures, such as zero-dimensional nanodots, one-dimensional nanowires and two-dimensional nanolayers, have attracted tremendous interest in recent years, due to their numerous potential applications, for example, in nanoelectronics, flexible electronics, photonics, sensors, and in energy harvesting and storage devices. Yet the application of semiconductor nanostructures on a large, industrial scale is hampered by their high fabrication costs, which is primarily due to the required high processing temperatures (500-1200°C) and/or the use of expensive catalysts, such as gold and silver. Advanced by the recently reached fundamental understanding of the metal-induced crystallization (MIC) of amorphous semiconductors [1, 2], an innovative set of routes for fabrication of various crystalline semiconductor nanostructures (nanodots, nanowires [3], nanolayers) have now been developed, which enable strikingly low growth temperatures (lower than 180 °C) and the use of cheap catalysts, like aluminium. The method can easily be scaled up to the industrial scale and also allows the direct fabrication of semiconductor-nanostructure-based devices on low-cost, but heat-sensitive, flexible substrates.[1] Z.M. Wang, J.Y. Wang, L.P.H. Jeurgens and E.J. Mittemeijer, Phys. Rev. Lett. 100 (2008) 125503. [2] Z.M. Wang, J.Y. Wang, L.P.H. Jeurgens and E.J. Mittemeijer, Phys. Rev. B 77 (2008) 045424.[3] Z.M. Wang, L. Gu, F. Phillipp, J.Y. Wang, L.P.H. Jeurgens and E.J. Mittemeijer, Adv. Mater. 23 (2011) 854.
3:45 PM - D7.5
Energy-Efficient Synthesis of Ferrite Powders and Films.
Ranajit Sai 1 2 , Suresh Kulkarni 1 2 , Navakanta Bhat 2 3 , Srinivasrao Shivashankar 1 2
1 Materials Research Centre, Indian Institute of Science, Bangalore, Karnataka, India, 2 Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore, Karnataka, India, 3 Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore, Karnataka, India
Show AbstractIn recent years, there has been significant effort in the synthesis of nanocrystalline spinel ferrites due to their unique properties. Among them, zinc ferrite has been widely investigated for countless applications. Many methods already explored for the synthesis of polycrystalline ferrites include ball milling and solid state reactions, each typically taking several hours of processing time, followed by annealing at high temperatures for hours. These steps constitute high overall energy requirement for the process and are contrary to modern industrial and environmental requirements. Solution-based synthesis routes offer relatively quick processes, but hours of annealing at elevated temperature is still unavoidable. Thus, there is need for a resource-effective process that can prepare ferrites quickly and efficiently without compromising material quality. In the present work, a novel microwave-assisted soft-chemical synthesis technique in the liquid medium has been developed for synthesis of ZnFe2O4 powder below 100°C, within 5 min. Instead of metal nitrates and chlorides, non-hazardous and easily soluble metal complexes (typically β-diketonates, in 1:2 molar proportion for Zn:Fe) featuring direct metal-to-oxygen bonds in their molecular structure were chosen as the precursors, not only to reduce the solution preparation time and overall process temperature, but also to end up with only water-soluble and non-toxic by-products. All solvents and ingredients were chosen carefully, to reduce the mixing time and to address related environmental issues. The solution then is subjected to irradiation in a microwave oven (2.45 GHz) for 5 minutes. The entire process, including solution preparation and centrifugation, requires < 30 min. As synthesized powder then annealed at 300oC for 2 hour in a conventional anneal (CA) schedule. Calculations show that 2 hour annealing takes ~15 times the energy as the rest of the process. To minimize this, a 2-min rapid anneal at 300oC (RA) is developed and shown to be sufficient to crystallize the ferrite particles, which show a saturation magnetization (MS) of 38 emu/g, compared with 39 emu/g for a 2-hr CA. This signifies that our process is efficient enough to reduce energy consumption by ~90% just by altering the anneal scheme. Recognising the criticality of anneal process to the energy budget, a more energy-efficient variation of the process was developed. By exposing the mother solution to single mode microwave radiation (2.45 GHz) in a closed chamber, operating pressure can be raised, which raises the reaction temperature without adding to the energy bill. The resulting powder is already nanocrystalline and ferrimagnetic zinc ferrite, eliminating the need for power-hungry annealing. Thus, present work offers a resource-effective and energy- efficient way of processing functional oxide ceramics. It will be shown that the process also can be employed to deposit crystalline thin films of ferrites.
D8: Sustainable and Energy-Efficient Synthesis II
Session Chairs
Wednesday PM, November 30, 2011
Back Bay B (Sheraton)
4:30 PM - **D8.1
Surface Engineering of Sustainable Cellulosic Materials by Atomic Layer Deposition.
Gregory Parsons 1
1 Chemical and Biomolecular Engineering, NC State University, Raleigh, North Carolina, United States
Show AbstractResearchers are looking to renewable and sustainable material resources and processes to fulfill product needs currently supplied by petrochemical-based polymers. New sustainable high surface area porous and materials, including spun, woven textiles and nonwoven fibrous mats can be used for separations, purification, and filtration