Este trabajo fue parcialmente financiado por un proyecto PEPS de Cellule Energie INSIS-CNRS (1D-RENOX) para ACG y el Gobierno español (MAT2012-35324 y PIE-201460I004).

1. Preparación del Sol <ol><li> Preparar una solución de ortosilicato de tetraetilo prehidrolizado (TEOS) el día antes de la preparación de las películas de gel en una campana de humos en la que se colocan una balanza de laboratorio y un agitador magnético. En este paso y en todo el protocolo de llevar una bata de laboratorio, guantes y gafas de seguridad. <ol><li> En un vaso de 50 ml que contenía una barra de agitación magnética recubierta de teflón pesan 1,68 g de CTAB, añadir 48,13 ml de etanol y 3,00 ml de HCl 35%, cubrir el vaso con un vidrio de reloj y revuelva hasta que el CTAB se disuelva por completo. </li><li> Añadir 7,37 ml de TEOS a la gota a gota vaso de precipitados (a una velocidad de alrededor de 1-2 gotas por segundo) mientras se agitaba, cubrir el matraz con un vidrio de reloj y se deja agitar O / N. </li></ol></li><li> El día siguiente, preparar una solución acuosa 1 M de 2+ Sr. Realice este y los siguientes pasos justo antes de la preparación de las películas de gel debido a que una solución de edad es propensa a re-precipitación de la sal Sr. <ol><li> Pesar 6,6654 g de SrCl 2 · 6H 2 O en un matraz aforado de 25 ml. </li><li> Añadir agua ultrapura (por ejemplo, Milli-Q) hasta 25 ml (menisco tangente a la marca de frasco) y cerrar el frasco con una tapa de plástico y agite suavemente el frasco para disolver el cloruro de estroncio. </li></ol></li><li> Añadir 2 ml de la solución acuosa 1 M de Sr 2+ al vaso de precipitados de vidrio de 50 ml que contiene el sol que se dejó en agitación O / N. Se agita la solución durante 25 min. </li><li> Deseche los residuos que se han generado con el tiempo de acuerdo a los protocolos de protección de seguridad y medio ambiente del laboratorio. </li></ol> 2. Gel de deposición de película de Si (100) Sustratos <ol><li> Preparación de los sustratos <ol><li> Cortar losas de Si de alrededor de 2 cm por 5 cm fuera de un 2 pulgadas de tipo p (100) oblea de silicio con un espesor de 200 micras mediante la escisión de la oblea en una dirección paralela o perpendicular al plano de la oblea usando una punta de diamante o una objeto afilado filo. Realice este paso en anuncioVance, por ejemplo, el día antes de la deposición de las películas de gel. </li><li> Justo antes de la deposición de los geles, limpiar los sustratos con etanol y dejarlos secar o utilizar un flujo de nitrógeno o aire comprimido para acelerar el secado. Realice este paso a la espera de la finalización de la etapa 1.3. </li></ol></li><li> Cubra las películas. Con el fin de obtener una estructura homogénea de macroporos realizar este paso en condiciones de humedad relativa entre 20% y 55% a TA. <ol><li> Establecer una secuencia de recubrimiento por inmersión. Seleccionar las posiciones inicial y final, teniendo en cuenta la longitud real de la losa de Si y el nivel de la solución en el vaso de precipitados de modo que la losa es por lo menos 2 cm por encima del nivel de la solución en la posición de partida y 1 cm por encima de la parte inferior de la vaso de precipitados al final de la inmersión. Establezca tanto las velocidades de inmersión y de abstinencia a 150 mm / min. Ajuste el tiempo de inmersión (tiempo en la posición final) a cero. </li><li> Al término de la etapa 1.3 lugar el vaso de precipitados con el por lolución en una posición bien centrada debajo de la losa de Si cuelga del brazo de inmersión revestidor. </li><li> Fijar un extremo de la losa Si al brazo dip-revestidor con el clip, asegurando la losa es lo más perpendicular posible con respecto a la horizontal. </li><li> Ejecutar la secuencia de recubrimiento por inmersión y soltar la losa de Si desde el brazo dip-revestidor. Repita los pasos 2.2.3 y 2.2.4 con losas de Si adicionales para producir más películas, teniendo cuidado de no extender estas preparaciones más allá de 1 hora, para asegurar que la estabilidad de la solución no se vea comprometida. </li></ol></li><li> Deseche las soluciones que se han generado con el tiempo de acuerdo a los protocolos de protección de seguridad y medio ambiente del laboratorio. </li></ol> 3. Gel de Cine La cristalización por tratamiento térmico <ol><li> El tratamiento térmico de las películas de gel de Si (100). <ol><li> Programa de un horno para realizar el siguiente tratamiento térmico en atmósfera de aire: calentamiento desde temperatura ambiente a 1000 ° C a 3 ° C / min, mantenimiento a 1.000 °; C durante 5 horas y enfriar a RT en 3 ° C / min. </li><li> Coloque los sustratos de Si recubiertas por inmersión en un barco de alúmina, introducirlo en el horno y ejecutar el tratamiento térmico. </li></ol></li><li> Limpieza de las películas cristalizadas. <ol><li> Sumergir las películas cristalizadas para 3 hr en HNO 3 concentrado a fin de eliminar las acumulaciones de Sr 2+ que han sido expulsadas a la superficie de la película durante la cristalización y luego enjuagar las películas primero con agua desionizada y después con etanol. </li></ol></li></ol>

<ol>
	<li>Esser, A. T., Smith, K. C., Gowrishankar, T. R., Vasilkoski, Z., Weaver, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+for+the+intracellular+manipulation+of+organelles+by+conventional+electroportation.">Mechanisms for the intracellular manipulation of organelles by conventional electroportation.</a> Biophys. J. 98 (11), 2506-2514 (2010).</li><li>Stava, E., Yu, M., Shin, H. C., Shin, H., Kreft, D. J., Blick, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+fabrication+and+piezoelectric+tuning+of+micro-+and+nanopores+in+single+crystal+quartz.">Rapid fabrication and piezoelectric tuning of micro- and nanopores in single crystal quartz.</a> Lab Chip. 13 (1), 156-160 (2013).</li><li>Varshneya, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fundamentals of Inorganic Glasses. , (1994).</li><li>Christov, M., Kirov, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+ratio+of+dissolving+surface+area/growing+surface+area+in+the+hydrothermal+growth+of+quartz.">The ratio of dissolving surface area/growing surface area in the hydrothermal growth of quartz.</a> J. Cryst. Growth. 131 (3-4), 560-564 (1993).</li><li>Bertone, J. F., Cizeron, J., Wahi, R. K., Bosworth, J. K., Colvin, V. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrothermal+synthesis+of+quartz+nanocrystals.">Hydrothermal synthesis of quartz nanocrystals.</a> Nano Lett. 3, 655-659 (2003).</li><li>Jiang, Y., Brinker, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrothermal+synthesis+of+monodisperse+single-crystalline+alpha-quartz+nanospheres.">Hydrothermal synthesis of monodisperse single-crystalline alpha-quartz nanospheres.</a> Chem. Comm. 47 (26), 7524-7526 (2011).</li><li>Okabayashi, M., Miyazaki, K., Kono, T., Tanaka, M., Toda, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+Spherical+Particles+with+Quartz+Single.">Preparation of Spherical Particles with Quartz Single.</a> Chem. Lett. 34 (1), 58-59 (2005).</li><li>Carretero-Genevrier, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soft-Chemistry-Based+Routes+to+Epitaxial+&#945;-Quartz+Thin+Films+with+Tunable+Textures.">Soft-Chemistry-Based Routes to Epitaxial &#945;-Quartz Thin Films with Tunable Textures.</a> Science. 340 (6134), 827-831 (2013).</li><li>Brinker, C. J., Clem, P. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quartz+on+Silicon.">Quartz on Silicon.</a> Science. 340 (6134), 818-819 (2013).</li><li>Brinker, C. J., Lu, Y., Sellinger, A., Fan, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaporation-Induced+Self-Assembly:+Nanostructures+Made+Easy.">Evaporation-Induced Self-Assembly: Nanostructures Made Easy.</a> Adv. Mater. 11 (7), 579-585 (1999).</li><li>Griffith, C. S., Sizgek, G. D., Sizgek, E., Scales, N., Yee, P. J., Luca, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mesoporous+Zirconium+Titanium+Oxides.+Part+1:+Porosity+Modulation+and+Adsorption+Properties+of+Xerogels.">Mesoporous Zirconium Titanium Oxides. Part 1: Porosity Modulation and Adsorption Properties of Xerogels.</a> Langmuir. 24 (21), 12312-12322 (2008).</li><li>Lu, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuous+formation+of+supported+cubic+and+hexagonal+mesoporous+films+by+sol-gel+dip-coating.">Continuous formation of supported cubic and hexagonal mesoporous films by sol-gel dip-coating.</a> Nature. 389 (6649), 364-368 (1997).</li><li>Drisko, G. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Water-Induced+Phase+Separation+Forming+Macrostructured+Epitaxial+Quartz+Films+on+Silicon.">Water-Induced Phase Separation Forming Macrostructured Epitaxial Quartz Films on Silicon.</a> Adv. Funct. Mater. 24 (35), 5494-5502 (2014).</li></ol>

Los autores no tienen nada que revelar.

El método presentado es un enfoque de abajo hacia arriba para producir películas de cuarzo macroporosas en Si. En comparación con el método estándar de producción de películas de cuarzo, una tecnología de arriba hacia abajo basa en corte y pulido de grandes cristales de hidrotérmicamente cultivadas, el método descrito en el protocolo permite la obtención de películas mucho más delgadas con espesores entre 150 y 450 nm que se pueden controlar con el tasa de retiro. Todos los detalles experimentales en materi...

Cuando un material piezoeléctrico como α-cuarzo se somete a una polarización de tensión se somete a una deformación mecánica. Si este material es poroso, estos cambios de volumen pueden conducir a la expansión de los poros o contracción, la creación de un sistema de respuesta similar a lo que se puede observar en la vivencia de orgánulos biológicos. 1 deformable poroso α-cuarzo se ha producido usando microfabricación, 2 pero estas técnicas aún no puede producir estructuras de poro 3-D, y diámetros de poro son del orden de cientos de nanómetros. La cristalización de sílice amorfa estructurado ha visto obstaculizado por la nucleación homogénea causada por energías superficiales elevadas y deformación arquitectónico debido a engrosamiento y la fusión. Además, dado que todas las formas de sílice se basan en extremadamente estables SiO 4 redes tetraédricos, las energías libres de formación de sílice amorfa, α-cuarzo y otros SiO 2 polimorfos son casi iguales en una amplia gama de temperaturas, Making difícil producir α-cuarzo como un único polimorfo de la cristalización de un gel de sílice amorfa. 3 Otro aspecto que hace más difícil la cristalización controlada de sílice amorfa estructurada es que el cuarzo presenta una velocidad de nucleación relativamente lento, pero una tasa de crecimiento extremadamente rápido, reportado entre 10-94 nm / seg. 4,5 nucleación lenta junto con el crecimiento rápido tiende a generar cristales mucho más grandes que la estructura nanoporoso original, por lo tanto se pierde la morfología original. Metales alcalinos, tales como Na + y Li +, se han utilizado para cristalizar α-cuarzo, con frecuencia en combinación con el tratamiento hidrotermal. 5,6 Además, un Ti 4+ / Ca 2+ combinación fue empleado para cristalizar partículas esféricas de sílice en cuarzo por una ruta química suave utilizando alcóxidos de silicio. 7 Sin embargo, la cristalización controlada de una película de sílice amorfa estructurada en cuarzo sigue siendo un desafío. 2 bajo presión ambiente y temperaturas relativamente bajas. 8,9 epitaxia, surge de la falta de coincidencia entre α-favorable de cuarzo y el sustrato &lt;100&gt; silicio, la producción de películas delgadas orientadas piezoeléctricos. La evaporación inducida por auto-ensamblaje para producir películas de sílice mesoporosos se ha utilizado desde 1999. 10 Esta técnica se ha estudiado y se aplica a una multitud de agentes de plantilla en diversas condiciones para producir poros de tamaños variables y mesofases. Se ha encontrado que los cambios en el tamaño de mesoporos subnanométrica pueden tener un efecto dramático sobre la difusión de solutos a través de sistemas porosos 11, validación de esta extensa atención a los poros estructura. Por otra parte, la accesibilidad al sistema de poros de sílice interna se puede obtener mediante el control de la fase micelar de la plantilla. 12 Aquí, la ruta de síntesis tsombrero permite un control sin precedentes sobre el tamaño de poro y grosor de las capas de sílice amorfa utilizando una novela separación de fases se demuestra. 13 Estas películas se infiltran con Sr (II) las sales y se cristalizó a alfa-cuarzo a 1000 ° C bajo aire a presión ambiente. El tamaño de poro retenible el uso de este proceso de cristalización se determina, y el efecto de espesor de pared y grosor de la película se estudia. Por último, la piezoelectricidad y la deformabilidad del sistema de poros se estudian.

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			<td height="21" style="height:21px;width:180px;">Furnace</td>
			<td style="width:281px;">Nabertherm&#160;</td>
			<td>R 50/250/12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">Atomic Force Microscope</td>
			<td style="width:281px;">Agilent&#160;</td>
			<td>5500 LS</td>
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			<td height="21" style="height:21px;width:180px;">Materials and Reagents&#160;</td>
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			<td height="21" style="height:21px;width:180px;">Silicon wafers</td>
			<td style="width:281px;">SHE Europe Ltd.</td>
			<td></td>
			<td></td>
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			<td height="21" style="height:21px;width:180px;">SrCl2&#183;6H2O</td>
			<td style="width:281px;">Aldrich</td>
			<td>13909</td>
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			<td height="21" style="height:21px;width:180px;">CTAB</td>
			<td style="width:281px;">Aldrich</td>
			<td>H5582</td>
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			<td height="21" style="height:21px;width:180px;">Ethanol Absolute&#160;</td>
			<td style="width:281px;">Aldrich</td>
			<td>161086</td>
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			<td height="21" style="height:21px;width:180px;">HCl 35% solution</td>
			<td style="width:281px;">PanReac</td>
			<td>721019</td>
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		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">TEOS</td>
			<td style="width:281px;">Aldrich</td>
			<td>131903</td>
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preparation of macroporous epitaxial quartz films on silicon by chemical solution deposition

This work describes the detailed protocol for preparing piezoelectric macroporous epitaxial quartz films on silicon(100) substrates. This is a three-step process based on the preparation of a sol in a one-pot synthesis which is followed by the deposition of a gel film on Si(100) substrates by evaporation induced self-assembly using the dip-coating technique and ends with a thermal treatment of the material to induce the gel crystallization and the growth of the quartz film. The formation of a silica gel is based on the reaction of a tetraethyl orthosilicate and water, catalyzed by HCl, in ethanol. However, the solution contains two additional components that are essential for preparing mesoporous epitaxial quartz films from these silica gels dip-coated on Si. Alkaline earth ions, like Sr2+ act as glass melting agents that facilitate the crystallization of silica and in combination with cetyl trimethylammonium bromide (CTAB) amphiphilic template form a phase separation responsible of the macroporosity of the films. The good matching between the quartz and silicon cell parameters is also essential in the stabilization of quartz over other SiO2 polymorphs and is at the origin of the epitaxial growth.

El progreso de la síntesis material fue controlado mediante el control de diferentes aspectos. Después del proceso de recubrimiento por inmersión se puede observar el aspecto de las películas, la aparición eventual de estructuras de difracción en el lugar reflejada de un láser verde y la microscopía electrónica de barrido (SEM) en el modo de electrones imágenes retrodispersada (Figura 1A-B). Después de que el proceso de cristalización es importante para graba...

Watch this Scientific Journal Video about Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition at JoVE.com

Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition

A protocol is presented for the preparation of piezoelectric macroporous epitaxial films of quartz on silicon by solution chemistry using dip-coating and thermal treatments in air.

Preparación de macroporosas Epitaxial cuarzo Films en silicio por la solución de deposición química

This work describes the detailed protocol for preparing piezoelectric macroporous epitaxial quartz films on silicon(100) substrates. This is a three-step ...

preparation-macroporous-epitaxial-quartz-films-on-silicon-chemical

Research

JoVE Journal

Chemistry

9.2K vistas.  CNRS-École Centrale de Lyon. A protocol is presented for the preparation of piezoelectric macroporous epitaxial films of quartz on silicon by solution chemistry using dip-coating and thermal treatments in air. 

Video: Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia

Plasma enhanced chemical vapor deposition (PECVD) of perfluoroalkanes has long been studied for tuning the wetting properties of surfaces. For high surface area microporous materials, such as metal-organic frameworks (MOFs), unique challenges present themselves for PECVD treatments. Herein the protocol for development of a MOF that was previously unstable to humid conditions is presented. The protocol describes the synthesis of Cu-BTC (also known as HKUST-1), the treatment of Cu-BTC with PECVD of perfluoroalkanes, the aging of materials under humid conditions, and the subsequent ammonia microbreakthrough experiments on milligram quantities of microporous materials. Cu-BTC has an extremely high surface area (~1,800 m2/g) when compared to most materials or surfaces that have been previously treated by PECVD methods. Parameters such as chamber pressure and treatment time are extremely important to ensure the perfluoroalkane plasma penetrates to and reacts with the inner MOF surfaces. Furthermore, the protocol for ammonia microbreakthrough experiments set forth here can be utilized for a variety of test gases and microporous materials.

Herein the procedures for plasma enhanced chemical vapor deposition of perfluoroalkanes on microporous materials such as metal-organic frameworks to enhance their stability and hydrophobicity are described. Furthermore, breakthrough testing of milligram quantities of samples is described in detail.

Preparación de hidrófobos orgánicos marcos de metal a través de Plasma Enhanced Chemical Vapor Deposition de perfluoroalcanos para la eliminación de amoniaco

Plasma enhanced chemical vapor deposition (PECVD) of perfluoroalkanes has long been studied for tuning the wetting properties of surfaces. For high ...

Investigación

Química

Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films

Atomically defined substrate surfaces are prerequisite for the epitaxial growth of complex oxide thin films. In this protocol, two approaches to obtain such surfaces are described. The first approach is the preparation of single terminated perovskite SrTiO3 (001) and DyScO3 (110) substrates. Wet etching was used to selectively remove one of the two possible surface terminations, while an annealing step was used to increase the smoothness of the surface. The resulting single terminated surfaces allow for the heteroepitaxial growth of perovskite oxide thin films with high crystalline quality and well-defined interfaces between substrate and film. In the second approach, seed layers for epitaxial film growth on arbitrary substrates were created by Langmuir-Blodgett (LB) deposition of nanosheets. As model system Ca2Nb3O10- nanosheets were used, prepared by delamination of their layered parent compound HCa2Nb3O10. A key advantage of creating seed layers with nanosheets is that relatively expensive and size-limited single crystalline substrates can be replaced by virtually any substrate material.

Various procedures are outlined to prepare atomically defined templates for epitaxial growth of complex oxide thin films. Chemical treatments of single crystalline SrTiO3 (001) and DyScO3 (110) substrates were performed to obtain atomically smooth, single terminated surfaces. Ca2 Nb3 O10- nanosheets were used to create atomically defined templates on arbitrary substrates.

Plantillas Atómicamente definidos para crecimiento epitaxial de óxido complejo Películas Delgadas

Atomically defined substrate surfaces are prerequisite for the epitaxial growth of complex oxide thin films. In this protocol, two approaches to obtain ...

Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene

Recent progress in the field of organic materials has yielded devices such as organic light emitting diodes (OLEDs) which have advantages not found in traditional materials, including low cost and mechanical flexibility. In a similar vein, it would be advantageous to expand the use of organics into high frequency electronics and spin-based electronics. This work presents a synthetic process for the growth of thin films of the room temperature organic ferrimagnet, vanadium tetracyanoethylene (V[TCNE]x, x~2) by low temperature chemical vapor deposition (CVD). The thin film is grown at &#60;60 &#176;C, and can accommodate a wide variety of substrates including, but not limited to, silicon, glass, Teflon and flexible substrates. The conformal deposition is conducive to pre-patterned and three-dimensional structures as well. Additionally this technique can yield films with thicknesses ranging from 30 nm to several microns. Recent progress in optimization of film growth creates a film whose qualities, such as higher Curie temperature (600 K), improved magnetic homogeneity, and narrow ferromagnetic resonance line-width (1.5 G) show promise for a variety of applications in spintronics and microwave electronics.

We present the synthesis of the organic-based ferrimagnet vanadium tetracyanoethylene (V[TCNE]x, x~2) via low temperature chemical vapor deposition (CVD). This optimized recipe yields an increase in Curie temperature from 400 K to over 600 K and a dramatic improvement in magnetic resonance properties.

Deposición de vapor químico de un imán Orgánica, vanadio tetracianoetileno

Recent progress in the field of organic materials has yielded devices such as organic light emitting diodes (OLEDs) which have advantages not found in ...

Preparation of Highly Porous Coordination Polymer Coatings on Macroporous Polymer Monoliths for Enhanced Enrichment of Phosphopeptides

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous polymer monoliths. The developed approach is based on the preparation of a macroporous polymer containing carboxylic acid functional groups and the subsequent step-by-step solution-based controlled growth of a layer of a porous coordination polymer on the surface of the pores of the polymer monolith. The prepared metal-organic polymer hybrid has a high specific micropore surface area. The amount of iron(III) sites is enhanced through metal-organic coordination on the surface of the pores of the functional polymer support. The increase of metal sites is related to the number of iterations of the coating process.
The developed preparation scheme is easily adapted to a capillary column format. The functional porous polymer is prepared as a self-contained single-block porous monolith within the capillary, yielding a flow-through separation device with excellent flow permeability and modest back-pressure. The metal-organic polymer hybrid column showed excellent performance for the enrichment of phosphopeptides from digested proteins and their subsequent detection using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presented experimental protocol is highly versatile, and can be easily implemented to different organic polymer supports and coatings with a plethora of porous coordination polymers and metal-organic frameworks for multiple purification and/or separation applications.

A procedure for the preparation of porous hybrid separation media composed of a macroporous polymer monolith internally coated by a high surface area microporous coordination polymer is presented.

Preparación de altamente poroso Coordinación Polymer Coatings en macroporosas Polymer Monolitos de Enriquecimiento mejorada de Phosphopeptides

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous ...

Preparation of Mica and Silicon Substrates for DNA Origami Analysis and Experimentation

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of these applications require interaction with and adhesion of DNA nanostructures to a substrate. Due to its atomically flat and easily cleaned nature, mica has been the substrate of choice for DNA origami experiments. However, the practical applications of mica are relatively limited compared to those of semiconductor substrates. For this reason, a straightforward, stable, and repeatable process for DNA origami adhesion on derivatized silicon oxide is presented here. To promote the adhesion of DNA nanostructures to silicon oxide surface, a self-assembled monolayer of 3-aminopropyltriethoxysilane (APTES) is deposited from an aqueous solution that is compatible with many photoresists. The substrate must be cleaned of all organic and metal contaminants using Radio Corporation of America (RCA) cleaning processes and the native oxide layer must be etched to ensure a flat, functionalizable surface. Cleanrooms are equipped with facilities for silicon cleaning, however many components of DNA origami buffers and solutions are often not allowed in them due to contamination concerns. This manuscript describes the set-up and protocol for in-lab, small-scale silicon cleaning for researchers who do not have access to a cleanroom or would like to incorporate processes that could cause contamination of a cleanroom CMOS clean bench. Additionally, variables for regulating coverage are discussed and how to recognize and avoid common sample preparation problems is described.

Reproducible cleaning processes for substrates used in DNA origami research are described, including bench-top RCA cleaning and derivatization of silicon oxide. Protocols for surface preparation, DNA origami deposition, drying parameters, and simple experimental set-ups are illustrated.

Preparación de Mica y Silicon Sustratos para el Análisis de Origami ADN y Experimentación

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of ...

Epitaxial Growth of Perovskite Strontium Titanate on Germanium via Atomic Layer Deposition

Atomic layer deposition (ALD) is a commercially utilized deposition method for electronic materials. ALD growth of thin films offers thickness control and conformality by taking advantage of self-limiting reactions between vapor-phase precursors and the growing film. Perovskite oxides present potential for next-generation electronic materials, but to-date have mostly been deposited by physical methods. This work outlines a method for depositing SrTiO3 (STO) on germanium using ALD. Germanium has higher carrier mobilities than silicon and therefore offers an alternative semiconductor material with faster device operation. This method takes advantage of the instability of germanium's native oxide by using thermal deoxidation to clean and reconstruct the Ge (001) surface to the 2&#215;1 structure. 2-nm thick, amorphous STO is then deposited by ALD. The STO film is annealed under ultra-high vacuum and crystallizes on the reconstructed Ge surface. Reflection high-energy electron diffraction (RHEED) is used during this annealing step to monitor the STO crystallization. The thin, crystalline layer of STO acts as a template for subsequent growth of STO that is crystalline as-grown, as confirmed by RHEED. In situ X-ray photoelectron spectroscopy is used to verify film stoichiometry before and after the annealing step, as well as after subsequent STO growth. This procedure provides framework for additional perovskite oxides to be deposited on semiconductors via chemical methods in addition to the integration of more sophisticated heterostructures already achievable by physical methods.

This work details the procedures for the growth and characterization of crystalline SrTiO3 directly on germanium substrates by atomic layer deposition. The procedure illustrates the ability of an all-chemical growth method to integrate oxides monolithically onto semiconductors for metal-oxide semiconductor devices.

Crecimiento epitaxial de perovskita del titanato de estroncio en el germanio a través de deposición de capas atómicas

Atomic layer deposition (ALD) is a commercially utilized deposition method for electronic materials. ALD growth of thin films offers thickness control and ...

Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films

Organo-lead halide perovskites have recently attracted great interest for potential applications in thin-film photovoltaics and optoelectronics. Herein, we present a protocol for the fabrication of this material via the low-pressure vapor assisted solution process (LP-VASP) method, which yields ~19% power conversion efficiency in planar heterojunction perovskite solar cells. First, we report the synthesis of methylammonium iodide (CH3NH3I) and methylammonium bromide (CH3NH3Br) from methylamine and the corresponding halide acid (HI or HBr). Then, we describe the fabrication of pinhole-free, continuous methylammonium-lead halide perovskite (CH3NH3PbX3 with X = I, Br, Cl and their mixture) films with the LP-VASP. This process is based on two steps: i) spin-coating of a homogenous layer of lead halide precursor onto a substrate, and ii) conversion of this layer to CH3NH3PbI3-xBrx by exposing the substrate to vapors of a mixture of CH3NH3I and CH3NH3Br at reduced pressure and 120 &#176;C. Through slow diffusion of the methylammonium halide vapor into the lead halide precursor, we achieve slow and controlled growth of a continuous, pinhole-free perovskite film. The LP-VASP allows synthetic access to the full halide composition space in CH3NH3PbI3-xBrx with 0&#160;&#8804; x&#160;&#8804; 3. Depending on the composition of the vapor phase, the bandgap can be tuned between 1.6 eV&#160;&#8804; Eg&#160;&#8804; 2.3 eV. In addition, by varying the composition of the halide precursor and of the vapor phase, we can also obtain CH3NH3PbI3-xClx. Films obtained from the LP-VASP are reproducible, phase pure as confirmed by X-ray diffraction measurements, and show high photoluminescence quantum yield. The process does not require the use of a glovebox.

Here, we present a protocol for the synthesis of CH3NH3I and CH3NH3Br precursors and the subsequent formation of pinhole-free, continuous CH3NH3PbI3-xBrx thin films for the application in high efficiency solar cells and other optoelectronic devices.

Proceso de solución asistida por Vapor de baja presión para banda sintonizables hueco agujero de alfiler-libre Methylammonium plomo haluro perovskita películas

Organo-lead halide perovskites have recently attracted great interest for potential applications in thin-film photovoltaics and optoelectronics. Herein, ...

Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, their high cost production and/or incompatibility with microfabrication technologies, due to the use of pre-deposited catalyst-seeds and/or high processing temperatures exceeding 900 &#176;C, represent a drawback for a widespread use of these methods. Here, however, we report the synthesis of ZnO rods via a non-catalyzed vapor-solid mechanism enabled by using an aerosol-assisted chemical vapor deposition (CVD) method at 400 &#176;C with zinc chloride (ZnCl2) as the precursor and ethanol as the carrier solvent. This method provides both single-step formation of ZnO rods and the possibility of their direct integration with various substrate types, including silicon, silicon-based micromachined platforms, quartz, or high heat resistant polymers. This potentially facilitates the use of this method at a large-scale, due to its compatibility with state-of-the-art microfabrication processes for device manufacture. This report also describes the properties of these structures (e.g., morphology, crystalline phase, optical band gap, chemical composition, electrical resistance) and validates its gas sensing functionality towards carbon monoxide.

Columnar zinc oxide structures in the form of rods are synthesized via aerosol-assisted chemical vapor deposition without the use of pre-deposited catalyst-seed particles. This method is scalable and compatible with various substrates based on either silicon, quartz or polymers.

Aerosol-asistida por deposición de Vapor químico del óxido de Metal estructuras: barras de óxido de Zinc

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, ...

Reactive Vapor Deposition of Conjugated Polymer Films on Arbitrary Substrates

We demonstrate a method of conformally coating conjugated polymers on arbitrary substrates using a custom-designed, low-pressure reaction chamber. Conductive polymers, poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propylenedioxythiophene) (PProDOT), and a semiconducting polymer, poly(thieno[3,2-b]thiophene) (PTT), were deposited on unconventional highly-disordered and textured substrates with high surface areas, such as paper, towels and fabrics. This reported deposition chamber is an improvement of previous vapor reactors because our system can accommodate both volatile and nonvolatile monomers, such as 3,4-propylenedioxythiophene and thieno[3,2-b]thiophene. Utilization of both solid and liquid oxidants are also demonstrated. One limitation of this method is that it lacks sophisticated in situ thickness monitors. Polymer coatings made by the commonly used solution-based coating methods, such as spin-coating and surface grafting, are often not uniform or susceptible to mechanical degradation. This reported vapor phase deposition method overcomes those drawbacks and is a strong alternative to common solution-based coating methods. Notably, polymer films coated by the reported method are uniform and conformal on rough surfaces, even at a micrometer scale. This feature allows for future application of vapor deposited polymers in electronics devices on flexible and highly textured substrates.

This paper presents a protocol for reactive vapor deposition of poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), and poly(thieno[3,2-b]thiophene) films on glass slides and rough substrates, such as textiles and paper.

Deposición de Vapor reactivo de polímero conjugado películas sobre sustratos de arbitrarias

We demonstrate a method of conformally coating conjugated polymers on arbitrary substrates using a custom-designed, low-pressure reaction chamber. ...

Deposition of Porous Sorbents on Fabric Supports

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material that can be subsequently treated by dip coating. Dip coating with a sol preparation provides a supported porous layer on the fabric. In this case, the porous layer is a porphyrin functionalized sorbent system based on a powdered material that has been demonstrated previously for the capture and conversion of phosgene. A representative coating is applied to cotton fabric at a loading level of 10 mg/g. This coating has minimal impact on water vapor transport through the fabric (93% of the support fabric rate) while significantly reducing transport of 2-chloroethyl ethyl sulfide (CEES) through the material (7% of support fabric rate). The described approaches are suitable for use with other fabrics providing amine and hydroxyl groups for modification and can be used in combination with other sol preparations to produce varying functionality.

This report details a microwave-initiated approach for deposition of porphyrin functionalized porous organosilicate sorbents on a cotton fabric and demonstrates reduction in 2-chloroethyl ethyl sulfide (CEES) transport through the fabric resulting from this treatment.

Deposición de los absorbentes porosos en soportes de tela

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material ...