Questo lavoro è stato parzialmente finanziato da un progetto PEPS di Cellule Energie INSIS-CNRS (1D-RENOX) per ACG e il governo spagnolo (MAT2012-35324 e PIE-201460I004).

1. Preparazione del sol <ol><li> Preparare una soluzione di prehydrolyzed tetraetilortosilicato (TEOS) il giorno prima della preparazione dei film di gel in una cappa aspirante in cui una bilancia da laboratorio e un agitatore magnetico sono vincolate. In questa fase e in tutto il protocollo indossare un camice da laboratorio, guanti e occhiali di protezione. <ol><li> In un bicchiere da 50 ml contenente un agitatore magnetico rivestito di Teflon pesare 1,68 g di CTAB, aggiungere 48,13 ml di etanolo e 3,00 ml di HCl 35%, coprire il becher con un vetro d&#39;orologio e mescolare fino a quando il CTAB è completamente sciolto. </li><li> Aggiungere 7,37 ml di TEOS alla goccia a goccia bicchiere (ad una velocità di circa 1-2 gocce al secondo), agitando, coprire il recipiente con un vetro da orologio e lasciarlo mescolare O / N. </li></ol></li><li> Il giorno successivo, preparare una soluzione acquosa 1 M di 2+ Sr. Eseguire questa e le seguenti operazioni appena prima della preparazione dei film gel perché una soluzione invecchiato è incline a ri-precipitazione del sale Sr. <ol><li> Pesare 6.6654 g di SRCL 2 · 6H 2 O in un pallone tarato da 25 ml. </li><li> Aggiungere ultrapura acqua (ad esempio, Milli-Q) fino a 25 ml (menisco tangente al contrassegno pallone) e chiudere il pallone con un tappo di plastica e agitare delicatamente il pallone sciogliere il cloruro di stronzio. </li></ol></li><li> Aggiungere 2 ml della soluzione acquosa 1 M di Sr 2+ al bicchiere di vetro da 50 ml contenente sol che è stato lasciato sotto agitazione O / N. Agitare la soluzione per 25 min. </li><li> Smaltire i residui che sono stati alla fine generati secondo i protocolli del laboratorio di tutela della sicurezza e dell&#39;ambiente. </li></ol> 2. Gel deposizione di film su Si (100) Substrati <ol><li> Preparazione dei substrati <ol><li> Tagliare Si lastre di circa 2 cm per 5 cm su un 2 pollici di tipo p (100) wafer di silicio con uno spessore di 200 micron, con l&#39;adesione del wafer in una direzione parallela o perpendicolare al piano wafer con una punta di diamante o di un oggetti taglienti. Eseguire questo passaggio a annunciovance, per esempio il giorno prima della deposizione dei film di gel. </li><li> Appena prima della deposizione dei gel, pulire i substrati con etanolo e lasciare asciugare o utilizzare un flusso di azoto o aria compressa per accelerare l&#39;asciugatura. Eseguire questo passaggio in attesa del completamento della fase 1.3. </li></ol></li><li> Cappotto film. Al fine di ottenere una struttura omogenea macropori eseguire questo passaggio in condizioni di umidità relativa tra il 20% e il 55% a temperatura ambiente. <ol><li> Stabilire una sequenza di rivestimento per immersione. Selezionare le posizioni iniziale e finale, tenendo conto della lunghezza effettiva della lastra Si e il livello della soluzione nel beaker in modo che la lastra è di almeno 2 cm sopra il livello della soluzione nella posizione di partenza e 1 cm dal fondo della beaker al termine dell&#39;immersione. Impostare sia le immersione e di prelievo velocità a 150 mm / min. Impostare il tempo di immersione (tempo alla posizione finale) a zero. </li><li> Al termine della fase di 1,3 posto il bicchiere con il modoluzione in una posizione ben centrata sotto la lastra Si appeso al braccio dip-dispositivo a induzione. </li><li> Fissare un&#39;estremità della lastra Si al braccio dip-coater con la clip, assicurando la lastra è più possibile perpendicolare rispetto all&#39;orizzontale. </li><li> Eseguire la sequenza di dip coating e sganciare la lastra Si dal braccio dip-dispositivo a induzione. Ripetere i punti 2.2.3 e 2.2.4 con l&#39;aggiunta di lastre di silicio per produrre più film, facendo attenzione a non estendere questi preparati oltre 1 ora, per assicurare che la stabilità della soluzione non è compromessa. </li></ol></li><li> Smaltire le soluzioni che sono state alla fine generati secondo i protocolli del laboratorio di tutela della sicurezza e dell&#39;ambiente. </li></ol> 3. Gel Film cristallizzazione mediante trattamento termico <ol><li> Trattamento termico dei film di gel su Si (100). <ol><li> Programma un forno per eseguire il seguente trattamento termico in atmosfera di aria: riscaldamento da RT a 1.000 ° C a 3 ° C / min, tenendo a 1.000 °; C per 5 ore e raffreddamento a RT a 3 ° C / min. </li><li> Posizionare i dip Si substrati rivestiti in barca allumina, introdurlo nel forno ed eseguire il trattamento termico. </li></ol></li><li> Pulizia dei film cristallizzati. <ol><li> Immergere le pellicole cristallizzati per 3 ore in HNO 3 concentrato per rimuovere gli accumuli di Sr 2+ che sono stati espulsi alla superficie del film durante la cristallizzazione e quindi risciacquare prima con acqua deionizzata e poi il film con etanolo. </li></ol></li></ol>

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	<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>

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Il metodo presentato è un approccio bottom-up per la produzione di film di quarzo macroporose su Si. Rispetto al metodo standard di produzione di film di quarzo, una tecnologia top-down basato sul taglio e la lucidatura di grandi cristalli idrotermica coltivate, il metodo descritto nel protocollo consente di ottenere film molto più sottili con spessore compreso tra 150 e 450 nm, che possono essere controllati con il tasso di ritiro. Tutti i dettagli sperimentali sul controllo di quarzo film di spessore, e la risposta ...

Quando un materiale piezoelettrico come α-quarzo viene sottoposto ad una polarizzazione di tensione subisce una deformazione meccanica. Se questo materiale è poroso, queste variazioni di volume possono portare all&#39;espansione dei pori o la contrazione, creando un sistema di risposta simile a quello che si può osservare nel vivere organelli biologici. 1 deformabile α-quarzo poroso è stato prodotto utilizzando microfabbricazione, 2 ma queste tecniche non possono ancora produrre strutture pori 3-D, e diametri dei pori sono dell&#39;ordine di centinaia di nanometri. Cristallizzazione di strutturato silice amorfa è stato ostacolato da nucleazione disomogenea causata da energie superficiali elevate e deformazione architettonico a causa di grossolani e fusione. Inoltre, dal momento che tutte le forme di silice sono costruiti su estremamente stabili SiO 4 reti tetraedrici, le energie libere di formazione di silice amorfa, α-quarzo e altri SiO 2 polimorfi sono quasi uguali in un ampio intervallo di temperature, making è difficile produrre α-quarzo come un singolo polimorfo dalla cristallizzazione di un gel di silice amorfa. 3 Un altro aspetto che rende difficile la cristallizzazione controllata di strutturato silice amorfa è che il quarzo presenta una velocità di nucleazione relativamente lento ma un tasso di crescita estremamente veloce, riportati tra 10-94 nm / sec. 4,5 lenta nucleazione accoppiato con rapida crescita tende a generare cristalli molto più grandi rispetto alla struttura nanoporoso originale, così la morfologia originaria viene persa. Metalli alcalini, quali Na + e Li +, sono stati utilizzati per cristallizzare α-quarzo, spesso in combinazione con il trattamento idrotermico. 5,6 Inoltre, un legame Ti 4+ / Ca 2+ combinazione è stata impiegata per cristallizzare particelle sferiche di silice nella quarzo per una via chimica morbido utilizzando alcossidi di silicio. 7, tuttavia, la cristallizzazione controllata di una pellicola strutturata silice amorfa in quarzo è rimasta una sfida. 2 sotto pressione ambiente e temperature relativamente basse. 8,9 epitassia, nasce dalla mancata corrispondenza tra α-favorevole quarzo e il substrato &lt;100&gt; silicio, la produzione di film sottili piezoelettrici orientati. È stato usato per evaporazione indotta autoassemblaggio di produrre film di silice mesoporosa dal 1999. 10 Questa tecnica è stata studiata e applicata ad una moltitudine di templanti in varie condizioni per produrre pori di dimensioni e mesophases variabili. Si è trovato che le variazioni di dimensione mesopore subnanometric possono avere un effetto drammatico sul soluto diffusione attraverso sistemi porosi 11, convalidando questa grande attenzione alla struttura dei pori. Inoltre, l&#39;accessibilità al sistema dei pori di silice interno può essere ottenuta controllando la fase micellare del modello. 12 Qui, la via di sintesi tcappello permette un controllo senza precedenti sullo spessore e dimensione dei pori di strati di silice amorfa con una separazione di fase romanzo è dimostrata. 13 Questi film sono infiltrati con (II) sali Sr e cristallizzato ad a-quarzo a 1000 ° C sotto aria a pressione ambiente. La dimensione dei pori retainable utilizza questo processo di cristallizzazione è determinata, e l&#39;effetto dello spessore della parete e spessore del film è studiato. Infine la piezoelettricità e la deformabilità del sistema di pori sono studiati.

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			<td height="21" style="height:21px;width:180px;">Dip coater</td>
			<td style="width:281px;">Nadetech&#160;</td>
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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>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">Materials and Reagents&#160;</td>
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			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">Silicon wafers</td>
			<td style="width:281px;">SHE Europe Ltd.</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">SrCl2&#183;6H2O</td>
			<td style="width:281px;">Aldrich</td>
			<td>13909</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:180px;">CTAB</td>
			<td style="width:281px;">Aldrich</td>
			<td>H5582</td>
			<td></td>
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		<tr height="21">
			<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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		<tr height="21">
			<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>
			<td></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.

Il progresso della sintesi materiale è stato controllato dal controllo di diversi aspetti. Dopo il processo di dip-coating si può osservare l&#39;aspetto dei film, l&#39;eventuale comparsa di strutture di diffrazione nel punto riflessa di un laser verde e la microscopia elettronica a scansione (SEM) immagini in modalità retrodiffusi elettroni (Figura 1A-B). Dopo il processo di cristallizzazione è importante registrare Atomic Force Microscopy (AFM) immagini topografic...

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.

Preparazione di macroporosi Epitassiali Films quarzo su silicio da Solution Chemical Deposition

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

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9.2K Views.  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.

Preparazione del idrofobi Frameworks Metal-Organic tramite Plasma avanzata Chemical Vapor Deposition del perfluoroalcani per la rimozione di ammoniaca

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

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Chimica

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.

Modelli atomicamente definiti per epitassiale crescita di ossido Complex Thin Films

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.

Chemical Vapor Deposition di un magnete biologico, 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 ...

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.

Preparazione di altamente poroso Coordinamento rivestimenti polimerici su macroporosi Polymer Monoliti di avanzata Arricchimento fosfopeptidi

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.

Preparazione di Mica e Silicon substrati per il DNA Origami Analisi e sperimentazione

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.

Crescita epitassiale di perovskite titanato di stronzio su Germanio 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 ...

Capillary Electrophoresis to Monitor Peptide Grafting onto Chitosan Films in Real Time

Free-solution capillary electrophoresis (CE) separates analytes, generally charged compounds in solution through the application of an electric field. Compared to other analytical separation techniques, such as chromatography, CE is cheap, robust and effectively requires no sample preparation (for a number of complex natural matrices or polymeric samples). CE is fast and can be used to follow the evolution of mixtures in real time (e.g., chemical reaction kinetics), as the signals observed for the separated compounds are directly proportional to their quantity in solution.
Here, the efficiency of CE is demonstrated for monitoring the covalent grafting of peptides onto chitosan films for subsequent biomedical applications. Chitosan&#39;s antimicrobial and biocompatible properties make it an attractive material for biomedical applications such as cell growth substrates. Covalently grafting the peptide RGDS (arginine - glycine - aspartic acid - serine) onto the surface of chitosan films aims at improving cell attachment. Historically, chromatography and amino acid analysis have been used to provide a direct measurement of the amount of grafted peptide. However, the fast separation and absence of sample preparation provided by CE enables equally accurate yet real-time monitoring of the peptide grafting process. CE is able to separate and quantify the different components of the reaction mixture: the (non-grafted) peptide and the chemical coupling agents. In this way the use of CE results in improved films for downstream applications.
The chitosan films were characterized through solid-state NMR (nuclear magnetic resonance) spectroscopy. This technique is more time-consuming and cannot be applied in real time, but yields a direct measurement of the peptide and thus validates the CE technique.

Free solution capillary electrophoresis is a fast, cheap and robust analytical method that enables the quantitative monitoring of chemical reactions in real time. Its utility for rapid, convenient and precise analysis is demonstrated here through analysis of covalent peptide grafting onto chitosan films for improved cell adhesion.

Elettroforesi capillare per monitorare Peptide innesto su Chitosano film in tempo reale

Free-solution capillary electrophoresis (CE) separates analytes, generally charged compounds in solution through the application of an electric field. ...

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.

Bassa pressione processo di soluzione Vapor-assistita per sintonizzabile Band Gap Pinhole Metilammonio piombo ad alogenuri Perovskite film

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-assisted Chemical Vapor Deposition di strutture in ossido di metallo: aste di ossido di zinco

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.