Name: surface functionalization of metal-organic frameworks for improved moisture resistance
Uploaded: 2018-09-05T15:30:00
Description: Watch this Scientific Journal Video about Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance at JoVE.com

Dette arbejde blev støttet af EU (ERC Stg Chem-fs-MOF 445 714122), spansk MINECO (Unit af Excellence MDM-2015-0538) og Generalitat Valenciana 447 (Grant GV/2016/137). C.M.-G. og J.C.-G. takke den spanske 448 MINECO for et Ramón y Cajal Fellowship og FPI stipendium 449 (CTQ2014-59209-P), henholdsvis. N.M.P. tak for Junta de 450 Andalusien for en postdoc stipendium P10-FQM-6050. Formål og 451 D.R.M. er også taknemmelig over for økonomisk støtte, der tilbydes af 452 projekt MAT2015-70615-R fra den spanske regering og 453 af EFRU-midler. ICN2 er finansieret af CERCA program/Generalitat de Catalunya og understøttes af programmet Severo Ochoa spanske Ministeriet for økonomi, industri og konkurrenceevne (MINECO, give nr. SEV-2013-0295).

1. Syntetisk Procedure af hdcat@HKUST
Bemærk: Hele processen skal udføres inde i en handskerummet for at undgå enhver kontakt med den omgivende fugt. Derfor, alle reagenser og opløsningsmidler skal være tørt og opbevaret i handskerummet.
<ol><li>Bringe en åben 4 mL hætteglas, to spatler og en 1 mL mikropipette i boksen handske.</li>
	<li>Overføre 50 mg af hdcat ind i hætteglasset. Bemærk: I nogle tilfælde kan en anti-statisk pistol være nødvendig for at undgå de uønskede v...

<ol>
	<li>Banerjee, D., 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=Metal-organic+framework+with+optimally+selective+xenon+adsorption+and+separation.">Metal-organic framework with optimally selective xenon adsorption and separation.</a> Nature Communications. 7, (2016).</li><li>Elsaidi, S. K., 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=Hydrophobic+pillared+square+grids+for+selective+removal+of+CO+2from+simulated+flue+gas.">Hydrophobic pillared square grids for selective removal of CO 2from simulated flue gas.</a> Chemical Communications. 51 (85), 15530-15533 (2015).</li><li>Furukawa, H., Cordova, K. E., O'Keeffe, M., Yaghi, O. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+chemistry+and+applications+of+metal-organic+frameworks.">The chemistry and applications of metal-organic frameworks.</a> Science. 341 (6149), 1230444 (2013).</li><li>Howarth, A. J., 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=Chemical,+thermal+and+mechanical+stabilities+of+metal-organic+frameworks.">Chemical, thermal and mechanical stabilities of metal-organic frameworks.</a> Nature Reviews Materials. 1 (3), 15018 (2016).</li><li>Burtch, N. C., Jasuja, H., Walton, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Water+Stability+and+Adsorption+in+Metal-Organic+Frameworks.">Water Stability and Adsorption in Metal-Organic Frameworks.</a> Chem Rev. , (2014).</li><li>Guo, P., Dutta, D., Wong-Foy, A. G., Gidley, D. W., Matzger, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Water+Sensitivity+in+Zn4O-Based+MOFs+is+Structure+and+History+Dependent.">Water Sensitivity in Zn4O-Based MOFs is Structure and History Dependent.</a> Journal of the American Chemical Society. , 150213132255001 (2015).</li><li>Gao, W. 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=Remote+stabilization+of+copper+paddlewheel+based+molecular+building+blocks+in+metal-organic+frameworks.">Remote stabilization of copper paddlewheel based molecular building blocks in metal-organic frameworks.</a> Chemistry of Materials. 27 (6), 2144-2151 (2015).</li><li>Devic, T., Serre, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+valence+3p+and+transition+metal+based+MOFs.">High valence 3p and transition metal based MOFs.</a> Chemical Society Reviews. 43 (43), 6097-6115 (2014).</li><li>He, H., 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=A+Stable+Metal-Organic+Framework+Featuring+a+Local+Buffer+Environment+for+Carbon+Dioxide+Fixation.">A Stable Metal-Organic Framework Featuring a Local Buffer Environment for Carbon Dioxide Fixation.</a> Angewandte Chemie - International Edition. 57 (17), 4657-4662 (2018).</li><li>Nguyen, J. G., Cohen, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Moisture-resistant+and+superhydrophobic+metal-organic+frameworks+obtained+via+postsynthetic+modification.">Moisture-resistant and superhydrophobic metal-organic frameworks obtained via postsynthetic modification.</a> Journal of the American Chemical Society. 132 (13), 4560-4561 (2010).</li><li>Sun, Q., 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=Imparting+amphiphobicity+on+single-crystalline+porous+materials.">Imparting amphiphobicity on single-crystalline porous materials.</a> Nature Communications. 7, 13300 (2016).</li><li>Decoste, J. B., Peterson, G. W., Smith, M. W., Stone, C. A., Willis, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+stability+of+Cu-BTC+MOF+via+perfluorohexane+plasma-enhanced+chemical+vapor+deposition.">Enhanced stability of Cu-BTC MOF via perfluorohexane plasma-enhanced chemical vapor deposition.</a> Journal of the American Chemical Society. 134 (3), 1486-1489 (2012).</li><li>Wang, S., 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=Surface-specific+functionalization+of+nanoscale+metal-organic+frameworks.">Surface-specific functionalization of nanoscale metal-organic frameworks.</a> Angewandte Chemie - International Edition. 54 (49), 14738-14742 (2015).</li><li>Sun, 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=A+molecular-level+superhydrophobic+external+surface+to+improve+the+stability+of+metal-organic+frameworks.">A molecular-level superhydrophobic external surface to improve the stability of metal-organic frameworks.</a> Journal of Materials Chemistry A. 5 (35), 18770-18776 (2017).</li><li>Saiz-Poseu, J., 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=Versatile+Nanostructured+Materials+via+Direct+Reaction+of+Functionalized+Catechols.">Versatile Nanostructured Materials via Direct Reaction of Functionalized Catechols.</a> Advanced Materials. 25 (14), 2066-2070 (2013).</li><li>de Oliveira, J. A. F., 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=Dopamine+polymerization+promoted+by+a+catecholase+biomimetic+Cu+II(&#181;-OH)Cu+IIcomplex+containing+a+triazine-based+ligand.">Dopamine polymerization promoted by a catecholase biomimetic Cu II(&#181;-OH)Cu IIcomplex containing a triazine-based ligand.</a> Dalton Transactions. 45 (39), 15294-15297 (2016).</li><li>Koval, I. A., Gamez, P., Belle, C., Selmeczi, K., Reedijk, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+models+of+the+active+site+of+catechol+oxidase:+mechanistic+studies.">Synthetic models of the active site of catechol oxidase: mechanistic studies.</a> Chemical Society Reviews. 35 (9), 814 (2006).</li><li>Yang, J., Cohen Stuart, M. A., Kamperman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Jack+of+all+trades:+versatile+catechol+crosslinking+mechanisms.">Jack of all trades: versatile catechol crosslinking mechanisms.</a> Chemical Society Reviews. 43 (43), 8271-8298 (2014).</li><li>Castells-Gil, J., Novio, F., Padial, N. M., Tatay, S., Ru&#237;z-Molina, D., Mart&#237;-Gastaldo, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surface+Functionalization+of+Metal-Organic+Framework+Crystals+with+Catechol+Coatings+for+Enhanced+Moisture+Tolerance.">Surface Functionalization of Metal-Organic Framework Crystals with Catechol Coatings for Enhanced Moisture Tolerance.</a> ACS Applied Materials and Interfaces. 9 (51), 44641-44648 (2017).</li><li>Wang, S., 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=Surface-Specific+Functionalization+of+Nanoscale+Metal-Organic+Frameworks.">Surface-Specific Functionalization of Nanoscale Metal-Organic Frameworks.</a> Angewandte Chemie. 127 (49), 14951-14955 (2015).</li></ol>

Metoden rapporteret i dette arbejde giver en simpel og effektiv tilgang til overflade ændring af MOF krystaller af direkte reaktion med syntetisk catechols på milde betingelser uanset funktionaliteten af kæden. I modsætning til den konventionelle tilgang til at producere polydopamine-lignende belægninger, kan denne rute udføres i vandfri og anaerobe betingelser og uden nogen base tilføjelse, som kunne bringe stabiliteten i MOF. Methanol og kloroform blev første gang valgt baseret på tidligere værker<sup class="...

Metal-økologiske rammer er en klasse af krystallinsk porøse materialer indbygget fra uorganiske metalliske komponenter, normalt kaldet sekundær bygning enheder (SBUs), holdt sammen af polytopic økologiske ligander gennem koordinerende obligationer. Den samlesæt af disse SBUs med økologisk linkers muliggør dannelsen af udvidet 3D porøse strukturer med meget høj overflade områder og lovende applikationer inden for gas opbevaring og adskillelse1,2, katalyse og sensing3. Den største begrænsning for deres anvendelighed er dog deres ringe stabilitet i vand4,5som de fleste af dem inkorporerer divalent metaller i deres struktur, der resulterer i labile koordinering obligationer, som dem, der opstod i klassisk materialer som MOF-56eller HKUST7.
Fælles tilgange til at løse dette problem indebærer på den ene side, at skabe stærkere koordinering obligationer ved brug af stærkt ladede metaller, som Zr eller Ti(IV), grundlæggende N-donor ligander7,8 eller ligander indarbejde syrer og grundlæggende websteder9. Men denne metode er begrænset til nye materialer og tillader ikke for at øge stabiliteten af MOF'erne allerede er til rådighed. På den anden side bruge tilgange til at forbedre stabiliteten af de allerede kendte materialer metoderne efter syntetiske ændring for at indføre hydrofobe grupper i det tomme rum ved post syntetiske ændring af linker10,11 eller af kemiske dampe deposition (CVD)12. Desværre, stabiliteten af disse metoder kommer på udgifterne til en drastisk reduktion i porøsiteten af materialet og anvendelse af sofistikerede instrumentation. Den seneste brug af modificerede phosphonic syrer, såsom 1,2-dioleoyl-sn-glycero-3-phosphate (DOPA)13 eller n- octadecylphosphonic acid (OPA)14, at give hydrophobicity i kendte Zr(IV) MOF'erne bør også fremhæves.
Catechol forbindelser, såsom dopamin, har været flittigt brugt til at functionalize en bred vifte af materialer gennem dannelsen af polydopamine15. Dannelsen af disse belægninger er dog begrænset til brugen af vandige bufferet løsninger til lidt grundlæggende løsninger, som ikke er egnet til MOF'erne med labile obligationer. Bortoluzzi et al. har for nylig rapporteret, at polydopamine kan fremstilles i løsning af et binuclear Cu(II) kompleks byder Cu2(µ-O) som en katalytisk16 centre, som viser catecholase-lignende katalytiske aktivitet minder af naturlige enzymer såsom catechol oxidase17 og tyrosinase18. For nylig, har vi vist, hvordan en MOF baseret på Cu(II) padle-hjulet SBUs tilsluttet via trimesate linkers, kendt som HKUST, kan være beskyttet mod hydrolytisk nedbrydning ved polymerisering af functionalized catechols, såsom 4-hepatdecyl-catechol (hdcat) eller fluorerede-4-undecylcatechol (fdcat), på overfladen af krystaller19. Denne simple metode viser, hvordan effektive funktionelle belægninger kan syntetiseres under milde betingelser uanset funktionaliteten af catechol og uden brug af buffer løsninger, som kunne bringe stabiliteten i rammen, på grund af biomimetiske katalytisk aktivitet af Cu(II) enheder. Vi mener, at denne nye metode kunne dannelsen af funktionelle belægninger, som udover beskyttelse fra hydrolytisk nedbrydning, kunne bruges til selektiv adsorption af chiral molekyler eller flygtige organiske forbindelser.

<table border="0" cellpadding="0" cellspacing="0" style="width:572px;" width="573">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Basolite C-300</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">688614</td>
			<td style="width:167px;">Commercial HKUST</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Anhydrous Methanol (99.8%)</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right">322415</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Anhydrous Chloroform (&#62;99%)</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td align="right">288306</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Mettler Toledo TGA/SDTA 851</td>
			<td style="width:71px;">Mettler Toledo</td>
			<td style="width:119px;"></td>
			<td>Thermogravimetric Analyser</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Agilent Cary 630 FTIR</td>
			<td style="width:71px;">Agilent</td>
			<td style="width:119px;"></td>
			<td>FT-IR Spectrophotometer, ATR Module</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">PANalytical X&#8217;Pert Pro</td>
			<td style="width:71px;">PANalytical</td>
			<td style="width:119px;"></td>
			<td>Powder XRD Diffractometer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">AUTOSORB-6 apparatus</td>
			<td style="width:71px;">Quantachrome</td>
			<td style="width:119px;"></td>
			<td>Nitrogen Isotherms were carried out with this equipment. Activation of the samples was carried out under dynamic vacuum at 170 &#176;C. Performed by the technical service of Universitat d&#39;Alacant.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">K-Alpha X-ray photoelectron spectrometer system</td>
			<td style="width:71px;">Thermo-Scientific</td>
			<td style="width:119px;"></td>
			<td>Analysis were performed at the X-Ray unit of the Universitat d&#39;Alacant</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">FEI Quanta 650 FEG scanning electron microscope</td>
			<td style="width:71px;">Fisher Scientific</td>
			<td style="width:119px;"></td>
			<td>Used to observe partcle morphologies and dimensions</td>
		</tr>
	</tbody>
</table>

surface functionalization of metal-organic frameworks for improved moisture resistance

Metal-økologiske rammer (MOF'erne) er en klasse af porøse uorganiske materialer med lovende egenskaber i gaslagre og adskillelse, katalyse og sensing. Men i hovedsagen begrænser deres anvendelighed er deres fattige stabilitet under fugtige forhold. De fælles metoder til at overvinde dette problem involverer dannelsen af stærk metal-linker obligationer ved hjælp af stærkt ladede metaller, som er begrænset til en række strukturer, indførelsen af alkylic grupper til rammerne af post syntetiske modifikation (PSM) eller kemiske dampe deposition (CVD) til at forbedre samlede hydrophobicity af rammerne. Disse sidste to fremkalder normalt en drastisk reduktion af porøsitet af materialet. Disse strategier tillader ikke for at udnytte egenskaber af MOF allerede tilgængelige og det er bydende nødvendigt at finde nye metoder til at øge stabiliteten i MOF'erne i vand samtidig med deres egenskaber intakt. Heri, rapporterer vi en roman metode til at øge vand stabiliteten af MOF krystaller byder Cu2(O2C)4 pagaj-hjulet enheder, såsom HKUST (hvor HKUST står for Hong Kong University of Science & Technology), med catechols functionalized med alkyl og fluoro-alkyl kæder. Ved at tage fordel af de umættede metal websteder og CuII ioner katalytiske catecholase-lignende aktivitet, vi er i stand til at oprette robuste hydrofobe belægninger gennem oxidation og efterfølgende polymerisation af catechol enheder på overfladen af den krystaller under anaerobe og vand-fri betingelser uden at forstyrre det underliggende struktur af rammerne. Denne tilgang ikke blot giver materialet med forbedret vand stabilitet, men også giver kontrol over funktionen af den beskyttende belægning, der muliggør udvikling af funktionelle belægninger til adsorption og separationer af flygtige organiske forbindelser . Vi er overbeviste om, at denne tilgang kunne også udvides til andre ustabile MOF'erne byder på åben metal websteder.

Alle reagenser og materialer blev opbevaret i handskerummet- og bruges som modtaget uden nogen yderligere rensning, medmindre andet er angivet. Hele processen er udført i en handskerummet for at undgå kontakt med fugtighed, der kunne forringe den ubestrøget materiale.
For at sikre reproducerbarheden under forsøgene, blev kommercielt tilgængelig HKUST med en gennemsnitlig partikelstørrelse tæt på 40-50 µm (<strong class=...

Watch this Scientific Journal Video about Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance at JoVE.com

Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance

Robuste funktionelle catechol belægninger blev produceret i ét trin ved direkte reaktion af det materiale, der er kendt som HKUST med syntetisk catechols under anaerobe forhold. Dannelse af homogene belægninger omkring hele krystal er tilskrevet den biomimetiske katalytisk aktivitet af Cu(II) dimerer på den udvendige overflade af krystaller.

Overflade Functionalization af Metal-økologiske rammer for forbedret fugt modstand

Metal-organic frameworks (MOFs) are a class of porous inorganic materials with promising properties in gas storage and separation, catalysis and sensing. ...

Improving water stability is critical for the integration of MOFs into chemically demanding applications. Our method can help to increase the stability of MOFs that are not stable in water. The main advantage of this technique is that not only allows the modification of the hydrophobicity of the coated material, but also allows us to have control over the functionality of the coating.This technique takes advantage of the catalytic open metal sites present in some MOFs, which can trigger the polymerization of the catechol molecules on the surface of the crystals without affecting the overall porosity of the material. First, bring a four-milliliter glass vial, two spatulas, and a one-milliliter micropipette into a glove box. Special care must be taken in order to maintain oxygen-free reaction conditions.Add 50 milligrams of hdcat into the glass vial. Then, add one milliliter of anhydrous chloroform to the glass vial. Following this, add 10 milligrams of HKUST to the hdcat solution, and seal the vial tightly.After removing the vial from the glove box, sonicate the suspension of HKUST and hdcat for a few seconds to homogenize the solution. Make sure the vial is tightly sealed, and place it in an oven at 70 degrees Celsius overnight. After removing the vial from the oven, transfer it to the glove box with a 15-milliliter centrifuge tube.In the glove box, transfer the contents of the vial to the centrifuge tube using fresh anhydrous chloroform. After removing the centrifuge tube from the glove box, separate the coated material by centrifugation at 3, 354 times g for one minute. Once the centrifuge tube is returned to the glove box, carefully extract the supernatant using a dropper and store it in a clean 40-milliliter glass vial.Next, suspend the coated material in three milliliters of anhydrous chloroform in order to remove polymerized catechol units that are not attached to the surface of the crystals. After removing the chloroform, suspend the coated material in three milliliters of anhydrous methanol in order to remove unreacted hdcat molecules. After repeating the washing step three times, transfer the washed hdcat-HKUST to a glass vial using anhydrous methanol.Once the coated solid has settled at the bottom of the vial, remove the supernatant and allow the powder to dry at room temperature in the glove box. Bring a four-milliliter glass vial, two spatulas, and a one-milliliter micropipette into the glove box. Add 50 milligrams of fdcat to the glass vial.Then, add one milliliter of anhydrous chloroform to the glass vial. Next, add 10 milligrams of HKUST to the fdcat solution, and seal the vial tightly. After removing the vial from the glove box, sonicate the suspension of HKUST and fdcat for a few seconds to homogenize the solution.Make sure the vial is tightly sealed, and place it in the oven at 70 degrees Celsius overnight. After removing the vial from the oven, transfer it to the glove box with a 15-milliliter centrifuge tube. In the glove box, transfer the contents of the vial to the centrifuge tube using fresh anhydrous chloroform.After removing the centrifuge tube from the glove box, separate the coated material by centrifugation at 3, 354 times g for one minute. Once the centrifuge tube is returned to the glove box, carefully extract the supernatant using a dropper and store it in a clean 40-milliliter glass vial. Following this, suspend the coated material in three milliliters of anhydrous chloroform in order to remove polymerized catechol units that are not attached to the surface of the crystals.After removing the chloroform, suspend the coated material in three milliliters of anhydrous methanol in order to remove unreacted fdcat molecules. After repeating the washing step three times, transfer the washed fdcat-HKUST to a glass vial using anhydrous methanol. Once the coated solid has settled at the bottom of the vial, remove the supernatant and allow the powder to dry at room temperature in the glove box.The surface-modified crystals show increased hydrophobicity when soaked in water. In comparison with HKUST, which immediately sinks to the bottom of the vial, hdcat-HKUST and fdcat-HKUST can stand in water for several days without sinking. Contact angle measurements confirm their superior hydrophobicity.The FT-IR spectrum of hdcat-HKUST shows bands corresponding to alkane C-H stretching vibrations of the hdcat alkyl chain, which are not present in HKUST. For fdcat-HKUST, alkane C-F stretching vibrations are visible in the spectrum, which are not observed in HKUST. SEM images of hdcat-HKUST and fdcat-HKUST show an external corrugated layer surrounding the crystals, which suggests an effective polymerization on the crystals while respecting their morphology.XPS measurements show the presence of copper I in hdcat-HKUST and fdcat-HKUST, which is attributed to the reaction of the catechol moieties by copper units on the surface and subsequent polymerization. The formation of catecholate coatings on HKUST proceeded with no impact on the crystalline structure of HKUST, as confirmed by powder x-ray diffraction measurements. This was also confirmed by porosity measurements at 77 kelvin, which showed that hdcat-HKUST and fdcat-HKUST retain their surface area with minor variations after the coating process.While attempting this procedure, it's important to maintain oxygen-free reaction conditions, as oxygen could promote the polymerization of the catechol molecules in solution rather than on the surface of the crystals. Following this procedure, we have been able to modify the wettability of MOF materials by simple functionalization of their external surfaces. Also, this technique enables us to have control over the functionality of the coating, which enables us to have novel functionalities which were not present in the bare material, such as chiral separation or VOCs capture.

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Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and ...

Synthesis of a Water-soluble Metal&#8211;Organic Complex Array

Syntese af en Vandopløseligt Metal-Organic Complex Array

We demonstrate a method for the synthesis of a water-soluble multimetallic peptidic array containing a predetermined sequence of metal centers such as ...

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

Udvikling af heterogene Enantioselektive katalysatorer ved hjælp af chiral metal-organiske rammer (MOFs)

Substrate size discrimination by the pore size and homogeneity of the chiral environment at the reaction sites are important issues in the validation of ...

Synthesis of Single-Crystalline Core-Shell Metal-Organic Frameworks

Syntese af enkeltkrystallinske kerne-shell metal-organiske rammer

Because of their designability and unprecedented synergistic effects, core-shell metal-organic frameworks (MOFs) have been actively examined recently. ...

A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks

En teknisk vejledning til udførelse af spektroskopiske målinger på metal-organiske rammer

Metal-organic frameworks (MOFs) offer a unique platform to understand light-driven processes in solid-state materials, given their high structural ...

Syntese af lavvalente MOF'er fra multitopic phosphin linkers

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers

Forfatter Spotlight: Eksperimentelle tilgange til syntese af lavvalente metalorganiske rammer fra multitopic phosphin linkers  

Eksperimentelle tilgange til syntese af lavvalente metal-organiske rammer fra multitopic phosphin linkers

Metal-organic frameworks (MOFs) are the subject of intense research focus due to their potential applications in gas storage and separation, biomedicine, ...

Magnetometrisk karakterisering af redox-aktive MOF'er faststofelektrokemi

Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks

Forfatter Spotlight: Magnetometrisk karakterisering af mellemprodukter i faststofelektrokemien af redox-aktive metalorganiske rammer  

Magnetometrisk karakterisering af mellemprodukter i faststofelektrokemi af redox-aktive metal-organiske rammer

Electrochemical energy storage has been a widely discussed application of redox-active metal-organic frameworks (MOFs) in the past 5 years. Although MOFs ...