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Tryptophan photooxidation promoted by new hybrid materials prepared by condensation of naphthalene imides with silicate by the sol-gel process

TRIBONI, Eduardo R.; CAVALHEIRO, Carla C. Schmitt; POLITI, Mario J.; BEMQUERER, Marcelo P.; RODRIGUES, Magali A.
Fonte: ELSEVIER SCIENCE SA Publicador: ELSEVIER SCIENCE SA
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
47.478706%
Three novel hybrid organic/inorganic materials were synthesized from 4-substituted (NO(2), Br, H) 1,8-naphthalene imide-N-propyltriethoxysilane by the sol-gel process. These materials were obtained as a xerogel and partially characterized. The ability to photosensitize the oxidation and degradation of tryptophan indole ring by these materials was studied through photophysical and photochemical techniques. Although the derivatives containing Br and NO(2) as substituent do not cause efficient tryptophan photodamage, the hybrid material obtained from 1,8-naphthalic anhydride is very efficient to promote tryptophan photooxidation. By using laser flash photolysis it was possible to verify the presence of naphthalene imide transient radical species. The presence of oxygen causes an increase of the yield of radical formation. These results suggest that the mechanism of photodegradation of tryptophan occurs by type I, i.e. the transient radical (TrpH(center dot+)) formed by the direct reaction of the triplet state of the naphthalene imide moiety with tryptophan. Thus a inorganic-organic hybrid material that can be used to promote the oxidation of biomolecules was obtained. (C) 2009 Elsevier B.V. All rights reserved.; FAPESP[04/15069-7]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); CAPES; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); CNPq

Materiais híbridos à base de sílica obtidos pelo método sol-gel; Silica based hybrid materials obtained by the sol-gel method

Benvenutti, Edilson Valmir; Moro, Celso Camilo; Costa, Tania Maria Haas; Gallas, Marcia Russman
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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This review deals with silica based hybrid materials obtained by the sol-gel method. It involves concepts, classifications and important definitions regarding the sol-gel method that allows obtaining materials with organic and inorganic components dispersed in a molecular or nanometric level. We discuss the properties and characteristics of hybrid materials related to experimental synthesis conditions. We devote a special attention to the nanostructured materials, where the self-organization is imposed by the organic component. Finally, we present some important applications of these materials based on their specific properties.

Cartilage and bone regeneration: how close are we to bedside?

Canadas, Raphael Faustino; Pina, S.; Marques, A. P.; Oliveira, Joaquim M.; Reis, R. L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Parte de Livro
Publicado em /12/2014 ENG
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The treatment/regeneration of bone and cartilage diseases or defects, whether induced by rheumatism, joint dysplasia, trauma, or surgery presents great challenges that have not been fully solved by the current therapies. In the last few years, tissue engineering and regenerative medicine have been proposing advanced tools and technologies for bone and cartilage tissue regeneration, and some of which have successfully reached the market. Beyond the source of cells, the creation of superior structures for replacing defective bone and cartilage requires strong research in biomechanical signaling and synthesis of advanced biomaterials to mimic human tissues at the most varied levels. Natural and synthetic polymers, bioresorbable inorganic materials, and composites have been investigated for its potential as scaffolding materials with enhanced mechanical and biological properties. Porous scaffolds, hydrogels, and fibers are the most commonly biomimetic structures used for bone and cartilage tissue engineering. Herein, the concepts and current treatment strategies for bone and cartilage repair, as well as biomimetic strategies for bone and cartilage tissue engineering are overviewed. A global review of the ongoing clinical trials and of the scaffolds commercially available for the repair of osteochondral tissue is also presented.

Hybrid organic-inorganic materials: application in oxidative catalysis

Rocha, G M S R O
Fonte: Nova Science Publishers Publicador: Nova Science Publishers
Tipo: Parte de Livro
ENG
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67.59085%
Oxidative catalysis has been and will be playing an important role in the production of large quantities of intermediates. This technology has a great potential for improvement and this has led to a series of better processes, including the development of a great diversity of suitable catalysts. Within these compounds, metal phosphates and phosphonates possessing layered and pillared structures were found to constitute a very good alternative as catalysts to be used in oxidative catalysis. Metal phosphates and phosphonates can be considered as strong inorganic solid acids and much of their catalytic activity has been attributed to the Brønsted acidity of the interlayered hydroxyl groups and to the Lewis acidity of the metal center. Metal phosphates and phosphonates can be obtained at low temperatures, in aqueous media, using soft chemical routes and their preparation is quite accessible if the correct phosphonic acids and phophates are available. These heterogeneous materials are very interesting from the economical as well as from the environmental points of view because of the high yields and short reaction times, easy recovery from the reaction mixtures and the possibility to perform reactions in solvent-free conditions. Due to their particular physical and chemical properties and high versatility...

Selective crystallization with preferred lithium-ion storage capability of inorganic materials

Liu, Fei; Song, Shuyan; Xue, Dongfeng; Zhang, Hongjie
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 21/02/2012 EN
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Lithium-ion batteries are supposed to be a key method to make a more efficient use of energy. In the past decade, nanostructured electrode materials have been extensively studied and have presented the opportunity to achieve superior performance for the next-generation batteries which require higher energy and power densities and longer cycle life. In this article, we reviewed recent research activities on selective crystallization of inorganic materials into nanostructured electrodes for lithium-ion batteries and discuss how selective crystallization can improve the electrode performance of materials; for example, selective exposure of surfaces normal to the ionic diffusion paths can greatly enhance the ion conductivity of insertion-type materials; crystallization of alloying-type materials into nanowire arrays has proven to be a good solution to the electrode pulverization problem; and constructing conversion-type materials into hollow structures is an effective approach to buffer the volume variation during cycling. The major goal of this review is to demonstrate the importance of crystallization in energy storage applications.

Inorganic Islands on a Highly Stretchable Polyimide Substrate

Vlassak, Joost J.; Sun, Jeong-Yun; Lu, Nanshu; Yoon, Juil; Oh, Kyu-Hwan; Suo, Zhigang
Fonte: Materials Research Society Publicador: Materials Research Society
Tipo: Artigo de Revista Científica
EN_US
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For a flexible electronic device integrating inorganic materials on a polymer substrate, the polymer can deform substantially, but the inorganic materials usually fracture at small strains. This paper describes an approach to make such a device highly stretchable. A polyimide substrate is first coated with a thin layer of an elastomer, on top of which SiNx islands are fabricated. When the substrate is stretched to a large strain, the SiNx islands remain intact. Calculations confirm that the elastomer reduces the strain in the SiNx islands by orders of magnitude.; Engineering and Applied Sciences

Engineered biomolecular interactions with inorganic materials : sequence, binding, and assembly

Peelle, Beau R
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 192 leaves
ENG
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47.75189%
Nanobiotechnology aims to exploit biomolecular recognition and self-assembly capabilities for integrating advanced materials into medicine and electronics. In particular, peptides have exhibited the ability to specifically bind to and/or control the synthesis of diverse inorganic and metallic materials including those with electronic, magnetic, and optical properties. However, in order to mature into an engineering discipline, a fundamental understanding of how peptide chemical composition and amino acid spatial arrangement relate to interfacial function and specificity is essential. This work discloses general principles governing peptide-inorganic material surface interactions at the level of amino acid functional groups. To facilitate fundamental studies, methodologies broadly applicable to probing sequence-activity relationships of peptide-inorganic material surface interactions were developed. A yeast surface display system adapted to liquid-solid interfaces enabled surgical manipulation of sequence through genetic techniques and rapid, semi- quantitation of peptide-materials binding strength. Cells displaying material specific polypeptides were also shown to form self-healing biofilms and discriminate between surfaces of fabricated heterostructure materials. The influence of peptide sequence on aqueous formation of photoluminescent CdS nanoparticles was studied with synthetic soluble peptides and higher throughput methods. Systematic study of peptide sequence-activity relationships concluded that surface binding depends primarily on composition; For the single crystalline II-VI semiconductors CdS...

Towards rational design of peptides for selective interaction with inorganic materials

Krauland, Eric Mark
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 141 p.
ENG
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47.5939%
Utilizing molecular recognition and self-assembly, material-specific biomolecules have shown great promise for engineering and ordering materials at the nanoscale. These molecules, inspired from natural biomineralization systems, are now commonly selected against non-natural inorganic materials through biopanning random combinatorial peptide libraries. Unfortunately, the challenge of studying the biological inorganic interface has slowed the understanding of interactions principles, and hence limited the number of downstream applications. This work focuses on the facile study of the peptide-inorganic interface using Yeast Surface Display. The general approach is to use combinatorial selection to suggest interaction principles followed by rational design to refine understanding. In this pursuit, two material groups-II-VI semiconductors and synthetic sapphire (metal oxides)-are chosen as inorganic targets due to their technological relevance and ease of study. First, yeast surface display (YSD) was established as a broadly applicable method for studying peptide-material interactions by screening a human scFv YSD library against cadmium sulfide (CdS), a II-VI semiconductor. The presence of multiple histidine residues was found to be necessary for mediating cell binding to CdS. As a follow-up...

Preparation of sol-gel hybrid materials from gamma-methacryloxypropyltrimethoxysilane and tetramethyl orthosilicate: study of the hydrolysis and condensation reactions

El Hadad, Amir; Carbonell, Diógenes; Barranco, V.; Jiménez Morales, Antonia; Casal, Blanca; Galván Sierra, Juan Carlos
Fonte: Springer Publicador: Springer
Tipo: info:eu-repo/semantics/submittedVersion; info:eu-repo/semantics/article Formato: application/pdf
Publicado em 01/12/2011 ENG
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Organic-inorganic hybrid materials suitable for the development of sol&-gel coatings for metallic surfaces were prepared by hydrolysis and condensation of gamma-methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethyl orthosilicate (TMOS). The hydrolysis of MAPTMS/TMOS was carried out in an ethanol/water solution. The prehydrolysis stage of MAPTMS/TMOS system was monitored by Fourier transform infrared spectroscopy (FTIR) and liquid-state 29Si and 13C nuclear magnetic resonance (29Si and 13C NMR). FTIR analysis indicated that the hydrolysis of MAPTMS/TMOS was accomplished as far as the (SiOMe) band corresponding to unhydrolyzed silane disappeared. The concentration of the alkoxy groups and the extent of self-condensation of mono-, di-, and trisubstituted siloxanes (T species) in the sol were estimated by using liquid-state 29Si NMR spectroscopy. The hydrolysis of the prepared sol was also evaluated by liquid-state 13C NMR spectroscopy. The results indicated that under the adopted synthesis strategy conditions, the hydrolysis process requires 4 h to be completed.; This work has been supported by the Ministry of Science and Innovation of Spain (Projects MAT2006-04486 and MAT2009-13530) and the Regional Community of Madrid (Project 2009/MAT-1585). AA El hadad acknowledges a predoctoral contract JAE financed by CSIC...

Assembly and detection of viruses and biological molecules on inorganic surfaces

Sinensky, Asher Keeling
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 175 p.
ENG
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57.5281%
This work is composed of three distinct, albeit related, projects. Each project is an exploration of the ways in which interactions between inorganic surfaces and biological molecules can be advantageously exploited. The first project entitled, Biomolecular Recognition of Crystal Defects extended the phage display technique to the detection of crystal defects. The system used is based on the M13 bacteriophage with 7-residue constrained random sequence on protein III. After considerable experimentation a procedure described as 'Diffuse Selection' was developed for selecting defects on crystal surfaces. Challenges occur because it is difficult to drive phage display towards the selection of particular surface features as opposed to whole surfaces. After multiple iterations, diffuse selection was optimized and consensus sequences were achieved. Virus binding was characterized using Atomic Force Microscopy, Fluorescene Microscopy and Titration. Using a simple bimolecular model, the binding sequence identified through this work is shown to have a binding constant 100,000 times better than a random peptide sequence. The second project entitled, Surface Patterning of Genetically Programmed Viruses, developed a generalizable approach to patterning viruses regardless of the genetic modification made to the virus. Genetic modifications are made in order to create viruses which will construct inorganic materials on their bodies in the appropriate chemical environment. Three generalizable virus patterning approaches were developed based on hydrophobic...

ARPES Line Shapes in FL and non-FL Quasi-Low-Dimensional Inorganic Metals

Gweon, G. -H.; Denlinger, J. D.; Allen, J. W.; Claessen, R.; Olson, C. G.; Hoechst, H.; Marcus, J.; Schlenker, C.; Schneemeyer, L. F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/03/2001
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Quasi-low-dimensional (quasi-low-D) inorganic materials are not only ideally suited for angle resolved photoemission spectroscopy (ARPES) but also they offer a rich ground for studying key concepts for the emerging paradigm of non-Fermi liquid (non-FL) physics. In this article, we discuss the ARPES technique applied to three quasi-low-D inorganic metals: a paradigm Fermi liquid (FL) material TiTe$_{2}$, a well-known quasi-1D charge density wave (CDW) material K$_{0.3}$MoO$_{3}$ and a quasi-1D non-CDW material Li$_{0.9}$Mo$_{6}$O$_{17}$. With TiTe$_2$, we establish that a many body theoretical interpretation of the ARPES line shape is possible. We also address the fundamental question of how to accurately determine the {\bf k}$_F$ value from ARPES. Both K$_{0.3}$MoO$_{3}$ and Li$_{0.9}$Mo$_{6}$O$_{17}$ show quasi-1D electronic structures with non-FL line shapes. A CDW gap opening is observed for K$_{0.3}$MoO$_{3}$, whereas no gap is observed for Li$_{0.9}$Mo$_{6}$O$_{17}$. We show, however, that the standard CDW theory, even with strong fluctuations, is not sufficient to describe the non-FL line shapes of K$_{0.3}$MoO$_{3}$. We argue that a Luttinger liquid (LL) model is relevant for both bronzes, but also point out difficulties encountered in comparing data with theory. We interpret this situation to mean that a more complete and realistic theory is necessary to understand these data.; Comment: 23 pages...

Controlled and Continuous Patterning of Organic and Inorganic Materials by Induced Nucleation in an Optical Tweezers

Roy, Basudev; Arya, Manish; Thomas, Preethi; Jürgschat, Julius Konstantin; Rao, Venkat; Banerjee, Ayan; Reddy, Chilla Malla; Roy, Soumyajit
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
57.296475%
We demonstrate for the first time controlled patterning by inducing nucleation of material from a dense aqueous dispersion or solution in an optical tweezers. A hot spot is formed on a glass surface by the trapping laser due to which a water vapor bubble is formed causing Gibbs-Marangoni convection of material around the bubble. This results in accretion of material around the bubble, which eventually nucleates into a crystalline state of the material. The nucleation site, when moved by translating the microscope stage of the optical tweezers apparatus, forms a pattern. We have demonstrated the technique using exotic inorganic materials such as soft oxometalates, and organic materials such as glycine, paracetamol, and a fluorescent dye such as perylene. We have written patterns over lengths of nearly 1 mm at the rate of 1 Hz, with best resolution of about 1 micron. The technique has potential for a wide range of applications ranging from solution processed printable electronics to controlled catalysis.; Comment: 23 pages, 5 figures

Hybrid improper ferroelectricity in a Multiferroic and Magnetoelectric hybrid organic-inorganic perosvkite

Stroppa, Alessandro; Barone, Paolo; Jain, Prashant; Perez-Mato, Jean Manuel; Picozzi, Silvia
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/03/2014
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There is great interest in hybrid organic-inorganic materials such as metal-organic frameworks (MOFs). The compounds [C(NH$_{2}$)$_{3}$]M(HCOO)$_{3}$, where M=Cu$^{2+}$ or Cr$^{2+}$ are Jahn-Teller (JT) active ions, are MOF with perovskite topology which crystallizes in polar space group Pna2$_{1}$. In inorganic compounds, octahedral tilting and Jahn-Teller structural distortions are usually non-polar distortions. However, in this MOF cooperative interactions between the antiferro-distortive distortions of the framework and the C(NH2)$_{3}$ organic cation via hydrogen bonding breaks the inversion symmetry and induces a ferroelectric polarization.[Angew. Chem. Int. Ed. 50, 5847, 2011] Our ab-initio study supports the picture of an orbital-order-induced ferroelectricity, a rare example of dipolar ordering caused by electronic degrees of freedom. The switching of polarization direction implies the reversal of the weak ferromagnetic component. The microscopic mechanism in this JT-based MOF with ABX$_{3}$ perovskite structure displays a Hybrid Improper Ferroelectric (HIF) state, arising from a trilinear coupling between different structural deformations that comprise tilting, rotations and Jahn-Teller distortions of both the BX$_{3}$ framework and the organic cation at the A sites. Since these distortion modes in perovskite-inorganic compounds usually freeze-in at elevated temperatures...

Chemical polymerization of polyaniline and polypyrrole by phosphomolybdic acid : In situ formation of hybrid organic-inorganic materials

Gómez-Romero, P.; Casañ Pastor, Nieves; Lira-Cantú, Monica
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
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International Symposium on the Reactivity of Solids. - Texto completo disponible en la web del autor: http://www.cienciateca.com/PAni_PPy_PMo12_Chem_SSI_97_101_875.pdf; The oxidative polymerization of aniline or pyrrole by phosphomolybdic acid (H3PMo12O40) is described. These reactions take place in the absence of other anions and result in the incorporation of the photoactive and electroactive PMo12O403− anion into the lattice of the polymer. The resulting hybrid materials present the good conductivity and polymeric nature of the matrix plus the added electroactivity of the inorganic cluster, which is anchored in the polymer and not exchanged upon reduction. The hybrids can work as electrodes harnessing the electrochemical properties of the polyoxometalic clusters; This work was financed by DGICYT (Spain) (PB93-0122). We also thank the Ministry of Education and Science for a predoctoral fellowship (MECAECI) awarded to M.L.C. Partial support by the Generalitat de Catalunya is also acknowledged.; Peer reviewed

Hybrid organic–inorganic nanocomposite materials for application in solid state electrochemical supercapacitors

Gómez-Romero, P.; Chojak, Malgorzata; Cuentas Gallegos, A. K.; Asensio, Juan Antonio; Kulesza, Pawel J.; Casañ Pastor, Nieves; Lira-Cantú, Monica
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
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Full-text version available Open Access at: http://www.cienciateca.com/SupercapPaniPmo12_Electrochem%20Comm_5_2003_149.pdf; Integration into a conducting polymer matrix to form a hybrid material is an effective way to harness the electrochemical activity of nanosized oxide clusters. By anchoring them into polyaniline, the reversible redox chemistry of the otherwise soluble polyoxometalate clusters can be combined with that of the conducting polymer and be put to work in energy storage applications. We present here preliminary results that show how the resulting hybrid polymer displays the combined activity of its organic and inorganic components to store and release charge in a solid state electrochemical capacitor device.; Partial financial support from the Ministry of Science and Technology (Spain) (Grants MAT2001-1709-C04-01 and MAT2002-04529-C03), and from the Domingo Martínez Foundation, as well as fellowships from the European Marie Curie Program (to M.C.), from the ministry of Education (Spain) (to J.A.A.) and from CONACYT (Mexico) (to K.C.G.) are gratefully acknowledged. P.J.K. and M.C. appreciate partial support from State Committee for Scientific Research (KBN), Poland (Grant 7 T09A 03120).; Peer reviewed

Chemical synthesis of hybrid materials based on PAni and PEDOT with polyoxometalates for electrochemical supercapacitors

Vaillant, Julien; Lira-Cantú, Monica; Cuentas Gallegos, A. K.; Casañ Pastor, Nieves; Gómez-Romero, P.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
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Advanced Functional Nanomaterials - from NanoscaleObjects to Nanostructered Inorganic and Hybrid Materials; Hybrid organic–inorganic materials based on conjugated polymers constitute state-of-the-art compounds with recognized technological implications. In the area of energy conversion, production and storage devices, these materials have been applied as electrodes for batteries, supercapacitors, fuel cells or solar cells, among others. Their importance relies on the wide variety of organic and inorganic counterparts that these hybrids can be made of. The properties from each part can be tailored in order to contribute to a final desired characteristic or the combined properties from both. The unique combination of useful properties found in these materials include electronic conductivity (e− or h+), ionic transport, reversible electroactivity, electrooptical properties typical of semiconductors as well as electrochromic, pH- and composition-dependent properties, all of them to add to their polymeric nature. This is an excellent basis for the design of hybrid materials in which either of these properties or their combinations work to enhance or combine with those of a myriad inorganic phases with electronic, magnetic, photochemical...

Hybrid materials. Functional properties. From Maya Blue to 21st century materials

Gómez-Romero, P.; Sánchez, Clément
Fonte: Royal Society of Chemistry (Great Britain) Publicador: Royal Society of Chemistry (Great Britain)
Tipo: Artículo Formato: 808619 bytes; application/pdf
ENG
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57.42963%
The field of hybrid organic-inorganic materials has reached a stage of ripeness that is beginning to make possible extraordinary new developments. On the one hand the field has witnessed a trend towards the design of functionality in hybrids materials, while broadening spectacularly the variety of hybrid combinations explored. On the other hand, improved understanding and control of the chemistry, processing and microstructure of these versatile nanocomposite systems announce a new landscape of opportunities in dealing with increasingly complex chemistries and materials.; Peer reviewed

Hybrid Nanocomposite Materials

Gómez-Romero, P.; Lira-Cantú, Monica
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Capítulo de libro Formato: 579917 bytes; image/jpeg
ENG
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In: Kirk-Othmer Encyclopedia of Chemical Technology; Hybrid organic–inorganic materials constitute a fast-growing field that has already led to a very large variety of materials and applications. These nanocomposite materials abound both with organic or inorganic matrices and represent oportunities to design eclectic materials by taking advantage of the best properties of their components. But the hybrid concept can even go beyond this approach by creating materials with novel structures or supramolecular architectures, with synergic properties, or even with activities impossible for the isolated components. This article is a general review of the field, discussing the different categories of materials according to their chemical nature and their applications as structural or functional materials. A variety of hybrids with organic matrics (most commonly polymers) are distinguished from these in which the dominating phase is inorganic (polymeric or extended in nature). To the category of silicon-based hybrids that predominated in the early literature a larger variety of hybrids has followed which includes, among many others, inorganic molecular species intergrated in organic polymers, perovskites built with organic and inorganic building blocks or polymer-inserted inorganic phases. All of them are categorized and discussed with emphasis on their many different applications and commercial developments.; Peer reviewed

Hybrid Organic-Inorganic Materials - In Search of Synergic Activity

Gómez-Romero, P.
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
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47.71621%
Full-text available Open Access at: http://www.cienciateca.com/PGR_Review_Hybrids_AdvMat2001.pdf; This review surveys the work developed in the field of functional hybrid materials, especially those containing conducting organic polymers (COPs), in combination with a variety of inorganic species, from molecular to extended phases, including clusters and nano-sized inorganic particles. Depending on the dominating structural matrix, we distinguish and analyze organic-inorganic (OI) hybrids, nanocomposite materials, and inorganic-organic (IO) phases. These materials have been used in a wide variety of applications, including energy-storage applications, electrocatalysis, the harnessing of electrochromic and photoelectrochromic properties, application in display devices, photovoltaics, and novel energy-conversion systems, proton-pump electrodes, sensors, or chemiresistive detectors, which work as artificial noses.; Peer reviewed

Carbon nanotube ‒ inorganic hybrids : from synthesis to application

Cabana Jiménez, Laura; Peral Pérez, José
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion
Publicado em //2015 ENG
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Aquesta Tesi descriu la preparació de varis híbrids formats per nanotubs de carboni i material inorgànic per a diferents aplicacions, que van des de l'electrònica fins a la biomedicina. El propòsit d'aquesta recerca ha estat treballar en la funcionalització de nanotubs de carboni mitjançant la decoració externa i l'emplenat amb materials inorgànics per obtenir híbrids amb propietats funcionals. Com a pas previ a la funcionalització, els nanotubs de carboni s'han de purificar per a eliminar les impureses no desitjades. En aquesta Tesi, hem proposat un mètode de purificació per a nanotubs de carboni multicapa consistent en l'ús servir vapor d'aigua, que és un agent oxidant lleu. Hem investigat l'efecte del temps de tractament amb vapor d'aigua en el grau de purificació i escurçament dels nanotubs de carboni. Hem vist que la purificació amb vapor d'aigua genera mostres de nanotubs de carboni d'alta qualitat i amb les puntes obertes. A més, hem apreciat que la seva llargada pot ser modulada fàcilment. Un cop purificats els nanotubs de carboni, hem preparat diferents tipus d'híbrids mitjançant la incorporació del material a les seves parets. Hem procedit a la decoració externa dels nanotubs de carboni amb nanopartícules d'òxid de ferro superparamagnètiques a través d'un mètode dut a terme in situ. S'ha aconseguit obtenir un agent de contrast dual tant per ressonància magnètica com per imatge nuclear a través del etiquetat de les nanopartícules amb 99mTc. A més...