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SAXS Studies of TiO2 Nanoparticles in Polymer Electrolytes and in Nanostructured Films  [PDF]
Aleksandra Turkovi?,Pavo Dub?ek,Krunoslav Jurai?,Antun Dra?ner,Sigrid Bernstorff
Materials , 2010, DOI: 10.3390/ma3114979
Abstract: Polymer electrolytes as nanostructured materials are very attractive components for batteries and opto-electronic devices. (PEO) 8ZnCl 2 polymer electrolytes were prepared from PEO and ZnCl 2. The nanocomposites (PEO) 8ZnCl 2/TiO 2 themselves contained TiO 2 nanograins. In this work, the influence of the TiO 2 nanograins on the morphology and ionic conductivity of the nanocomposite was systematically studied by transmission small-angle X-ray scattering (SAXS) simultaneously recorded with wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) at the synchrotron ELETTRA. Films containing nanosized grains of titanium dioxide (TiO 2) are widely used in the research of optical and photovoltaic devices. The TiO 2 films, prepared by chemical vapor deposition and e-beam epitaxy, were annealed in hydrogen atmospheres in the temperature range between 20 °C and 900 °C in order to study anatase-rutile phase transition at 740 °C. Also, grazing-incidence small angle X-ray scattering (GISAXS) spectra for each TiO 2 film were measured in reflection geometry at different grazing incident angles. Environmentally friendly galvanic cells, as well as solar cells of the second generation, are to be constructed with TiO 2 film as working electrode, and nanocomposite polymer as electrolyte.
Advanced colloidal nanostructures for electronic applications  [PDF]
Christian Klinke
Physics , 2015,
Abstract: A review of nanostructured materials synthesized by colloidal chemistry for electronic applications
SAXS/WAXS/DSC Study of Temperature Evolution in Nanopolymer Electrolyte  [PDF]
Aleksandra Turkovic,Mario Rakic,Pavo Dubcek,Magdy Lucic-Lavcevic,Sigrid Bernstorff
Physics , 2008,
Abstract: Electrolytes as nanostructured materials are very attractive for batteries or other types of electronic devices. (PEO)8ZnCl2 polymer electrolytes and nanocomposites (PEO)8ZnCl2/TiO2 were prepared from PEO and ZnCl2 and with addition of TiO2 nanograins. The influence of TiO2 nanograins was studied by small-angle X-ray scattering (SAXS) simultaneously recorded with wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) at the synchrotron ELETTRA. It was shown by previous impedance spectroscopy (IS) that the room temperature conductivity of nanocomposite polymer electrolyte increased more than two times above 65oC, relative to pure composites of PEO and salts. The SAXS/DSC measurements yielded insight into the temperature-dependent changes of the grains of the electrolyte as well as to differences due to different heating and cooling rates. The crystal structure and temperatures of melting and crystallization of the nanosize grains was revealed by the simultaneous WAXS measurements.
Nanostructured thin films obtained by electrodeposition over a colloidal crystal template: applications in electrochemical devices
Gon?ales, Vinicius R.;Massafera, Mariana P.;Benedetti, Tania M.;Moore, David G.;Torresi, Susana I. Córdoba de;Torresi, Roberto M.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000400010
Abstract: colloidal particles have been used to template the electrosynthesis of several materials, such as semiconductors, metals and alloys. the method allows good control over the thickness of the resulting material by choosing the appropriate charge applied to the system, and it is able to produce high density deposited materials without shrinkage. these materials are a true model of the template structure and, due to the high surface areas obtained, are very promising for use in electrochemical applications. in the present work, the assembly of monodisperse polystyrene templates was conduced over gold, platinum and glassy carbon substrates in order to show the electrodeposition of an oxide, a conducting polymer and a hybrid inorganic-organic material with applications in the supercapacitor and sensor fields. the performances of the resulting nanostructured films have been compared with the analogue bulk material and the results achieved are depicted in this paper.
Research Progress on Nanostructured Radar Absorbing Materials  [PDF]
Yanmin Wang, Tingxi Li, Lifen Zhao, Zuwang Hu, Yijie Gu
Energy and Power Engineering (EPE) , 2011, DOI: 10.4236/epe.2011.34072
Abstract: Nanostructured radar absorbing materials (RAMs) have received steadily growing interest because of their fascinating properties and various applications compared with the bulk or microsized counterparts. The increased surface area, number of dangling bond atoms and unsaturated co-ordination on surface lead to interface polarization, multiple scatter and absorbing more microwave. In this paper, four types of nanostructured RAMs were concisely introduced as follows: nanocrystal RAMs, core-shell nanocomposite RAMs, nanocomposite of MWCNT and inorganic materials RAMs, nanocomposite of nanostructured carbon and polymer RAMs. Their microwave properties were described in detail by taking various materials as examples
Use of synchrotron radiation SAXS to study the first steps of the interaction between sodium dodecyl sulfate and charged liposomes  [PDF]
O. López,M. Cócera,R. Pons,H. Amenitsch,J. Caelles,J. L. Parra,L. Coderch,A. de la Maza
Spectroscopy: An International Journal , 2002, DOI: 10.1155/2002/714548
Abstract: The technique of time resolved small angle X–ray scattering (SAXS) using a synchrotron radiation source was used to study the structural transformations as well as the kinetic associated with the first steps of the solubilization of liposomes induced by the anionic surfactant sodium dodecyl sulfate (SDS). Neutral and electrically charged (anionic and cationic) liposomes were used to investigate the effect of the electrostatic charges on these initial steps. The mechanism that induces the solubilization process consisted in an adsorption of surfactant on the bilayers and a desorption of mixed micelles from the liposomes surface to the aqueous medium. Regardless of the type of charge of the liposome the time needed for the desorption of the first mixed micelles was shorter than that for the complete adsorption of the surfactant on the liposomes surface. The present work demonstrates that the adsorption of the SDS molecules on liposomes was slower when the charges of surfactant and lipids were the same. As for the release of mixed micelles from the surface of these liposomes, this process was slower when the charges of surfactant and lipids were opposite.
Microgels: Novel Colloidal Materials  [cached]
Fernández-Nieves, A.,Fernández-Barbero, A.,de las Nieves, F. J.
Boletín de la Sociedad Espa?ola de Cerámica y Vidrio , 2000,
Abstract: Microgels are novel colloidal gels widely used because of the swelling or de-swelling exhibited under specific external conditions. In this work, the swelling and de-swelling of microgel particles is experimentally described. The medium pH, salt concentration and osmotic stress, are the three variables with which the change of phase has been realised. All transitions are found to occur well above the critical point of the system. Additionally, the basic applications in which the given transition is employed are described. Los microgeles son geles coloidales que se emplean por el inflado y/o desinflado que manifiestan ante ciertas condiciones externas. En este trabajo, se describe experimentalmente el inflado y el desinflado de partículas de gel. El pH del medio, su concentración iónica y el esfuerzo osmótico externo son las variables externas que se emplean para provocar el cambio de fase en las partículas. Todas las transiciones ocurren por encima del punto crítico del sistema. Adicionalmente, se presentan algunas de las aplicaciones en donde se emplea la transición provocada por la variable externa concreta.
State-of-the-Art and Perspectives in the Field of Particulate Nanostructured Materials
RAAndrevski,

材料科学技术学报 , 1998,
Abstract: A great attention has been paid to the research and development of nanostructured materials.The main preparation methods of ultrafine particles and nanostructured materials have been summarized. The applications of zone typical nanostructured materials have also been reviewed.The peculiar characteristics and properties. such as density, grain size, hardness, superplasticity,magnetic and catalytic properties have been discussed
Lyotropic liquid crystal directed synthesis of nanostructured materials
Cuiqing Wang, Dairong Chen and Xiuling Jiao
Science and Technology of Advanced Materials , 2009,
Abstract: This review introduces and summarizes lyotropic liquid crystal (LLC) directed syntheses of nanostructured materials consisting of porous nanostructures and zero-dimensional (0-D), one-dimensional (1-D) and two-dimensional (2-D) nanostructures. After a brief introduction to the liquid crystals, the LLCs used to prepare mesoporous materials are discussed; in particular, recent advances in controlling mesostructures are summarized. The LLC templates directing the syntheses of nanoparticles, nanorods, nanowires and nanoplates are also presented. Finally, future development in this field is discussed.
Hierarchically nanostructured materials for sustainable environmental applications  [PDF]
Zheng Ren,Yanbing Guo,Cai-Hong Liu,Pu-Xian Gao
Frontiers in Chemistry , 2013, DOI: 10.3389/fchem.2013.00018
Abstract: This review presents a comprehensive overview of the hierarchical nanostructured materials with either geometry or composition complexity in environmental applications. The hierarchical nanostructures offer advantages of high surface area, synergistic interactions, and multiple functionalities toward water remediation, biosensing, environmental gas sensing and monitoring as well as catalytic gas treatment. Recent advances in synthetic strategies for various hierarchical morphologies such as hollow spheres and urchin-shaped architectures have been reviewed. In addition to the chemical synthesis, the physical mechanisms associated with the materials design and device fabrication have been discussed for each specific application. The development and application of hierarchical complex perovskite oxide nanostructures have also been introduced in photocatalytic water remediation, gas sensing, and catalytic converter. Hierarchical nanostructures will open up many possibilities for materials design and device fabrication in environmental chemistry and technology.
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