The authors acknowledge National Science Foundation grant CHE- 1214068 for supporting this research project.

1. Herstellung von GMS <ol><li> Nutzen Sie alle Chemikalien, die in dem folgenden Verfahren wie erhalten. </li><li> Vorbereitung 75 ml 2 M Salzsäure (HCl) -Lösung. Wiegen 2,0 g Poly (ethylenglycol) -block-poly (propylenglykol) -block-poly (ethylenglycol) (S123, Mw = 5800) und Überführung in den hergestellten 75 ml 2 M HCl-Lösung. Bei RT gelten Magnetrührstab in die Lösung bei einer Geschwindigkeit von 350 U / min, bis P123 vollständig gelöst ist. Die Lösung wird klar sein. </li><li> Wiegen 4 g Tetraethoxysilan (TEOS, MW = 208,33) in einem kleinen Fläschchen und Übertragung 180 ul von Bis [3- (triethoxysilyl) propyl] tetrasulfid (TESPTS, MW = 538,94) in das Fläschchen. Langsam schüttelt die Fläschchen, um die beiden Chemikalien mischen. In einer anderen Phiole wiegen 38 mg Chlorgoldsäure (HAuCl 4, 99,90%) und in 1 ml entionisiertem Wasser gelöst. </li><li> Erhöhen die P123 Lösungs-Temperatur auf 35 ° C in ein Ölbad mit Temperatur von dem Thermoelement gesteuert wird. </li><li> Sie das gesamte Gemisch aus TEOS undTESPTS in Schritt 1.3 auf den P123-Lösung hergestellt, und halten Sie die Lösung bei kräftigem magnetischem Rühren mit 700 U / min. Bewahren Sie die Lösung unter Rühren 2 Minuten, dann fügen Sie alle HAuCl 4 Lösung in Schritt 1.3 tropfenweise innerhalb von 30 Sekunden hergestellt. </li><li> Die Lösung wird unter Rühren bei 700 U / min für 24 h bei 35 ° C. </li><li> Nach 24 Stunden wird die Lösung in einer verschlossenen Flasche und lagern in einem Ofen bei 100 ° C für 72 Stunden eingestellt. Dies wird als hydrothermale Verarbeitung. </li><li> Nach der hydrothermalen Verarbeitung, filtriert die Lösung mit einem # 1 Filterpapier und Unterdruck unter einem Trichter, dann waschen mit Wasser zweimal und Ethanol dreimal zur Entfernung restlichen HCl. Bei jedem Waschvorgang, fügen Sie Wasser oder Ethanol 1 cm über feste und warten Sie, das Material zu trocknen. </li><li> Übertragen Fällung aus Filtration, um einen Keramiktiegel und kalzinieren bei 550 ° C für 4 Stunden. Stellen Sie die Rampenprogramm wie folgt: 25 ° C bis 550 ° C für 2 Stunden halten bei 550 ° C für 4hr, dann lassen Sie die Probe in Ofen bleiben bei geschlossener Tür, bis die Temperatur unter 40 ° C. </li><li> Nach dem Kalzinieren zu übertragen, um ein Produkt zu einem Glas mit einem Kunststoffspachtel. Das synthetisierte Material hat eine rote Farbe. </li></ol> 2. Katalytische Reaktion, Oxidation von Benzylalkohol <ol><li> Da die Oxidation von Benzylalkohol ist eine Flüssigphasenreaktion ohne separates Lösungsmittel Maßnahme 5 ml Benzylalkohol (99,8%) und überträgt es in einen 25 ml Dreihalskolben, dann ein Gewicht von 10 mg GMS Katalysator ist und Benzyl hinzuzufügen Alkohol. </li><li> Einrichtung einer temperaturgeregelten Ölbad mit Magnetrührer, um genaue und gleichmäßige Steuerung der Reaktionstemperatur zu gewährleisten. </li><li> Setzen Sie die Kolben mit Benzylalkohol und Katalysator in das Ölbad, stellen Sie die Temperatur auf 100 ° C und unter Rühren bei 150 U / min. </li><li> Fließt Sauerstoffgas mit 99,9% Reinheit in den Kolben bei 2 ml / min durch eine Massenflusssteuerung gesteuert. </li><li> Wenn dasTemperatur des Ölbads 100ºC erreicht und stabilisiert, einzuführen Sauerstoffgas in den Dreihalskolben gegeben. </li><li> Halten Sie die Sauerstoffströmungsrate und Temperatur konstant, und die die Reaktion für 6 Stunden gehen. </li><li> Nach der Reaktion zu filtern, um ein Produkt mit einem # 1 Filterpapier. Sammeln Sie die flüssige Phase und einen aliquoten zu einer Gaschromatographie (GC) Fläschchen. In der GC-Fläschchen, mischen vier Teile HPLC Essigsäure für jeden ein Teil Probe (Verwenden Sie beispielsweise 36 &amp; mgr; l Probe und 144 ul Essigsäure.) Setzen Sie die Fläschchen auf einem Gaschromatographen Autosampler für die Analyse. Abwaschen der feste Niederschlag auf dem Filterpapier mit DI-Wasser und Ethanol gewaschen und dann zu ermöglichen, in der Luft trocknen. Sammeln Sie die getrockneten Feststoff mit einem Spatel als Recycling-Katalysator. </li><li> Wiederholen Sie das gleiche Experiment Vorgang ab Schritt 2.3 durch 2.7 mit Recycling-Katalysator dreimal. In jeder Wiederholung, passen Sie die Menge an Benzylalkohol, um den in Schritt 2.2 beschrieben Verhältnis entsprechen. </li></ol> 3. Tippen Standmal Behandlung von GMS für die Prüfung der thermischen Stabilität <ol><li> Wiegen Sie drei separate 300 mg Portionen synthetisiert GMS, und speichern sie in Glasfläschchen. Diese werden als Batch 1, Charge 2 und Charge 3. Halten Batch 1 als Kontrollgruppe bezeichnet, und legte Charge 2 Charge 3 und in einen Ofen für die thermische Verarbeitung. </li><li> Programm der Ofen wie folgt für die Verarbeitung bei 400 ° C: 0,5 h in eine Rampe von 25 ° C bis 400 ° C, halten bei 400 ° C für 4 Stunden, damit die Probe in dem Ofen mit der Tür bleibt, bis die Temperatur sinkt geschlossen unter 40 ° C. Setzen Charge 2 in einem Tiegel und das Programm starten. </li><li> Programm der Ofen wie folgt für die Verarbeitung bei 650 ° C: 0,75 h Rampe von 25 ° C bis 650 ° C, halten bei 650 ° C für 4 Stunden, damit die Probe in dem Ofen verbleiben die Tür geschlossen, bis die Temperatur unter 40 ° C. Setzen Charge 3 in einem Tiegel und das Programm starten. </li></ol> 4. Charakterisierungder GMS Materials 21,22 <ol><li> Auf der Physisorption Instrument, GMS Degas Materialien mit folgendem Programm: 90 ° C für 60 min und dann 350 ° C für 480 min. Führen Sie Voll Isotherme Analyse der entgasten Materialien Physisorption Daten zu erhalten. </li><li> Disperse GMS Probe auf einem 200-mesh löchrigen Kohlen TEM-Gitter und beobachten die Probe unter einem Transmissionselektronenmikroskop. Beschränken Vergrößerung unter 44,000X, um das Material zu schützen. </li><li> Führen XRD mit Cu Ka-Strahlung (λ = 1,5418 Å). Set Röhrenspannung von 45 kV und Röhrenstrom von 40 mA. Sammeln Intensität im 2θ zwischen 10 ° und 90 ° mit einer Schrittweite von 0,008 ° und einer Messdauer von 5 s bei jedem Schritt. </li></ol>

<ol>
	<li>Liguras, D. K., Kondarides, D. I., Verykios, X. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+of+hydrogen+for+fuel+cells+by+steam+reforming+of+ethanol+over+supported+noble+metal+catalysts.">Production of hydrogen for fuel cells by steam reforming of ethanol over supported noble metal catalysts.</a> Appl. Catal. B-Environ. 43 (4), 345-354 (2003).</li><li>Gelin, P., Primet, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complete+oxidation+of+methane+at+low+temperature+over+noble+metal+based+catalysts:+a+review.">Complete oxidation of methane at low temperature over noble metal based catalysts: a review.</a> Appl. Catal. B-Environ. 39 (1), 1-37 (2002).</li><li>Lu, S. F., Pan, J., Huang, A. B., Zhuang, L., Lu, J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alkaline+polymer+electrolyte+fuel+cells+completely+free+from+noble+metal+catalysts.">Alkaline polymer electrolyte fuel cells completely free from noble metal catalysts.</a> Proc. Natl. Acad. Sci. U. S. A. 105 (52), 20611-20614 (2008).</li><li>Ma, C. 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=Catalytic+oxidation+of+benzyl+alcohol+on+Au+or+Au&#8211;Pd+nanoparticles+confined+in+mesoporous+silica.">Catalytic oxidation of benzyl alcohol on Au or Au&#8211;Pd nanoparticles confined in mesoporous silica.</a> Applied Catalysis B: Environmental. 92 (1-2), 202-208 (2009).</li><li>Bamwenda, G. R., Tsubota, S., Nakamura, T., Haruta, 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+influence+of+the+preparation+methods+on+the+catalytic+activity+of+platinum+and+gold+supported+on+TiO2+for+CO+oxidation.">The influence of the preparation methods on the catalytic activity of platinum and gold supported on TiO2 for CO oxidation.</a> Catalysis Letters. 44 (1-2), 83-87 (1997).</li><li>Brown, K. R., Walter, D. G., Natan, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seeding+of+colloidal+Au+nanoparticle+solutions.+2.">Seeding of colloidal Au nanoparticle solutions. 2.</a> Improved control of particle size. 12 (2), 306-313 (2000).</li><li>Niesz, K., Grass, M., Somorjai, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precise+control+of+the+Pt+nanoparticle+size+by+seeded+growth+using+EO13PO30EO13+triblock+copolymers+as+protective+agents.">Precise control of the Pt nanoparticle size by seeded growth using EO13PO30EO13 triblock copolymers as protective agents.</a> Nano Lett. 5 (11), 2238-2240 (2005).</li><li>Yuranov, I., 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=Pd/SiO2+catalysts:+synthesis+of+Pd+nanoparticles+with+the+controlled+size+in+mesoporous+silicas.">Pd/SiO2 catalysts: synthesis of Pd nanoparticles with the controlled size in mesoporous silicas.</a> J. Mol. Catal. A-Chem. 192, 1-2 (2003).</li><li>Brinas, R. P., Hu, M. H., Qian, L. P., Lymar, E. S., Hainfeld, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+nanoparticle+size+controlled+by+polymeric+Au(I)+thiolate+precursor+size.">Gold nanoparticle size controlled by polymeric Au(I) thiolate precursor size.</a> J. Am. Chem. Soc. 130 (3), 975-982 (2008).</li><li>Zhu, H. G., Liang, C. D., Yan, W. F., Overbury, S. H., Dai, S. <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+highly+active+silica-supported+Au+catalysts+for+CO+oxidation+by+a+solution-based+technique.">Preparation of highly active silica-supported Au catalysts for CO oxidation by a solution-based technique.</a> J. Phys. Chem. B. 110 (22), 10842-10848 (2006).</li><li>Gabaldon, J. P., Bore, M., Datye, 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=Mesoporous+silica+supports+for+improved+thermal+stability+in+supported+Au+catalysts.">Mesoporous silica supports for improved thermal stability in supported Au catalysts.</a> Top. Catal. 44 (1-2), 253-262 (2007).</li><li>Li, F. B., Li, X. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+enhancement+of+photodegradation+efficiency+using+Pt-TiO2+catalyst.">The enhancement of photodegradation efficiency using Pt-TiO2 catalyst.</a> Chemosphere. 48 (10), 1103-1111 (2002).</li><li>Sakthivel, 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=Enhancement+of+photocatalytic+activity+by+metal+deposition:+characterisation+and+photonic+efficiency+of+Pt,+Au+and+Pd+deposited+on+TiO2+catalyst.">Enhancement of photocatalytic activity by metal deposition: characterisation and photonic efficiency of Pt, Au and Pd deposited on TiO2 catalyst.</a> Water Res. 38 (13), 3001-3008 (2004).</li><li>Jia, C. G., Wang, Y. P., Feng, H. 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+and+Catalytic+Properties+Of+Polymer-Supported+Fe-Co-Cu+And+Fe-Co-Au+Pentametallic+Clusters.">Preparation and Catalytic Properties Of Polymer-Supported Fe-Co-Cu And Fe-Co-Au Pentametallic Clusters.</a> React. Polym. 18 (3), 203-211 (1992).</li><li>Yu, X. 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=Reduced+graphene+oxide+supported+Au+nanoparticles+as+an+efficient+catalyst+for+aerobic+oxidation+of+benzyl+alcohol.">Reduced graphene oxide supported Au nanoparticles as an efficient catalyst for aerobic oxidation of benzyl alcohol.</a> Appl. Surf. Sci. 280, 450-455 (2013).</li><li>Xu, Y. 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=Au@Pt+core-shell+nanoparticles+supported+on+multiwalled+carbon+nanotubes+for+methanol+oxidation.">Au@Pt core-shell nanoparticles supported on multiwalled carbon nanotubes for methanol oxidation.</a> Catal. Commun. 13 (1), 54-58 (2011).</li><li>Baker, C. O., 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=Size+Control+of+Gold+Nanoparticles+Grown+on+Polyaniline+Nanofibers+for+Bistable+Memory+Devices.">Size Control of Gold Nanoparticles Grown on Polyaniline Nanofibers for Bistable Memory Devices.</a> ACS Nano. 5 (5), 3469-3474 (2011).</li><li>Wei, G. -. T., Yang, Z., Lee, C. Y., Yang, H. Y., Wang, 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=Aqueous&#8722;Organic+Phase+Transfer+of+Gold+Nanoparticles+and+Gold+Nanorods+Using+an+Ionic+Liquid.">Aqueous&#8722;Organic Phase Transfer of Gold Nanoparticles and Gold Nanorods Using an Ionic Liquid.</a> J. Am. Chem. Soc. 126 (16), 5036-5037 (2004).</li><li>Gadenne, B., Hesemann, P., Moreau, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Supported+ionic+liquids:+ordered+mesoporous+silicas+containing+covalently+linked+ionic+species.">Supported ionic liquids: ordered mesoporous silicas containing covalently linked ionic species.</a> Chemical Communications. 15, 1768-1769 (2004).</li><li>Yang, J. 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=Understanding+preparation+variables+in+the+synthesis+of+Au/Al2O3+using+EXAFS+and+electron+microscopy.">Understanding preparation variables in the synthesis of Au/Al2O3 using EXAFS and electron microscopy.</a> Applied Catalysis A: General. 291 (1-2), 73-84 (2005).</li><li>Chen, L. 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=Intercalation+of+aggregation-free+and+well-dispersed+gold+nanoparticles+into+the+walls+of+mesoporous+silica+as+a+robust+&#8216;green&#8217;+catalyst+for+n-alkane+oxidation.">Intercalation of aggregation-free and well-dispersed gold nanoparticles into the walls of mesoporous silica as a robust &#8216;green&#8217; catalyst for n-alkane oxidation.</a> Journal of the American Chemical Society. 131, 914-915 (2009).</li><li>Wang, X., 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=Nanoscale+gold+intercalated+into+mesoporous+silica+as+a+highly+active+and+robust+catalyst.">Nanoscale gold intercalated into mesoporous silica as a highly active and robust catalyst.</a> Nanotechnology. 23, 294010-294018 (2012).</li><li>Chen, L. 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=Controlled+synthesis+of+nanoscale+icosahedral+gold+particles+at+room+temperature.">Controlled synthesis of nanoscale icosahedral gold particles at room temperature.</a> Chemcatchem. 4, 1662-1667 (2012).</li></ol>

The authors have nothing to disclose.

Im Syntheseprotokoll ist darauf zu Tensidkonzentration pH-Lösung und der Reaktionstemperatur für die erfolgreiche Bildung von GMS. Die kritischen Schritte 1.2, 1.3, 1.4 und 1.6. Die oben genannten Parameter steuern die kritische Packungsparameter und Phase Mizellen aus Tensid gebildet. Die Phase und die Morphologie der Mizelle bestimmt den Endzustand Silica-Matrix, die als Rahmen für die GMS dient. Auch bei der Entstehung wichtig ist die Reihenfolge und die Zeit, die HAuCl Lösung zuzugeben. TEOS und TESPTS wirken al...

Als eine neue Technologie, die ein großes Potenzial in der Katalyse-Anwendungen hat, haben nanoskaligen Materialien intensive Forschungsinteresse in den letzten Jahrzehnten erhielt. Unter den nanoskaligen Katalysatoren berichtet, haben Edelmetallkatalysatoren wie Au, Ag, Pd und Pt weltweite Aufmerksamkeit 1-3 angezogen. Wählen katalytischer Reaktionen gehören die Oxidation von Kohlenmonoxid Forscher auf Au, Heck-Reaktion auf Pd-Katalysatoren und Wasserspaltung mit Pt. Trotz der vielversprechenden katalytische Potential wird nanoskalige Gold in ihrer Anwendbarkeit wegen der Deaktivierung von Vergiftungen, Verkokung thermischen Abbau, und Sintern beschränkt. Es wurde berichtet, dass Gold, als Vertreter für Edelmetalle, hat eine hohe Selektivität und ist weniger anfällig für Metall Auslaugen Überoxidation und Selbstvergiftung 4. Jedoch ist die katalytische Leistung von Gold hängt stark von der Partikelgröße. Haruta et al. Hat die Beziehung zwischen Katalysatorleistung und gehen gemeldetld Clusterdurchmesser, was die höchste Aktivität von Gold-Katalysatoren mit Partikelgröße ~ 2,7 nm 5. Die Teilchengröße der Edelmetalle können durch das Herstellungsverfahren 6-9 gesteuert werden; jedoch das Haupthindernis zur breiten Anwendung bleibt Aggregation und Aktivitätsverlust. Um das Problem der Sinterung zu lösen, ist ein übliches Verfahren, um nanoskalige Teilchen auf einem Trägermaterial zu immobilisieren. Verschiedene Trägermaterialien aufgebracht wurden einschließlich poröses Siliciumdioxid 10-11, halbleitende Metalloxide 12-13, Polymere 14, Graphen 15 und 16 Kohlenstoffnanoröhren. Unter den verwendeten Materialien ist poröses Siliciumdioxid ein attraktives Material als Träger, weil es nur schwach sauren, relativ inert, thermisch und chemisch stabil und kann mit sehr gut definierten meso- / Mikroporosität hergestellt werden. Die poröse Struktur bietet eine gute Unterstützung für Metallpartikel, sondern auch vermittelt größenselektive Substrat Zugang zuDie Metallkatalysatoren. Diese Selektivität ist wegen der Abstimmbarkeit mit diesen porösen Materialien verbunden sind besonders vielversprechend. Oft werden Goldpartikel als äußerst mobil auf Siliciumdioxidoberflächen 17-18 zu sein und bilden leicht sehr groß (über 50 nm) unreaktiv Teilchen, wenn sie hohen Temperaturen ausgesetzt wird, so dass es schwierig zu Goldnanopartikeln auf Kieselgel 19 vorzubereiten. Mukherjee et al. Berichteten Immobilisierung monodisperse gold auf mesoporösen Siliciumdioxid MCM-41 3-Aminopropyl-trimethoxysilan und 3-Mercaptopropyl-triethoxysilan sowie die unterstützten Goldnanopartikel wurde gefunden, daß für Hydrierungsreaktionen hochaktiv, und ein Auswaschen von Gold wurde festgestellt, in der Reaktion 20. Nach dem Bericht der Oberflächenmodifikation von mesoporösen Siliciumdioxid berichteten wir ein Verfahren, um Gold herzustellen interkaliert in die Wand des mesoporösen Siliciumdioxid (GMS). Darüber hinaus bietet das mesoporöse Siliciumdioxid Ansatz eine skalierbare apAnsatz, um potenziell unabhängig zu verändern den Katalysator und porösen Umgebung. Da katalytische Prozesse von entscheidender wirtschaftlicher Bedeutung könnten die Vorteile weit reich sein. Die Fähigkeit zur Entwicklung &quot;grüner&quot; Katalysatoren würde eine tiefgreifende positive Auswirkungen auf die Umwelt haben und zur Verbesserung der Wirtschaftlichkeit und Ressourceneffizienz wichtige industrielle Prozesse.

<table><tbody><tr><td>poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)</td><td>Aldrich</td><td>435465-250ML</td><td></td></tr><tr><td>tetraethoxysilane</td><td>TCI</td><td>201-083-8</td><td></td></tr><tr><td>bis[3-(triethoxysilyl)propyl]-tetrasulfide</td><td>GELEST</td><td>SIB1825.0-100GM</td><td></td></tr><tr><td>chloroauric acid</td><td>Aldrich</td><td>520918-1G</td><td></td></tr><tr><td>benzyl alcohol</td><td>Sigma-Aldrich</td><td>305197-1L</td><td></td></tr><tr><td>nitrogen physisorption</td><td>Micromeritics</td><td>Tristar II</td><td></td></tr><tr><td>X-ray diffraction</td><td>Philips</td><td>X&#039;Pert Pro</td><td></td></tr><tr><td>transmission electron microscopy</td><td>Philips</td><td>CM200</td><td></td></tr><tr><td>gas chromatography</td><td>Shimadzu</td><td>GC-2010</td><td></td></tr></tbody></table>

synthesis and catalytic performance of gold intercalated in the walls of mesoporous silica

Als vielversprechenden katalytisch aktiven Nanoreaktor wurden Gold-Nanopartikel in mesoporösen Siliciumdioxid (GMS) interkaliert erfolgreich synthetisiert und Eigenschaften der Materialien wurden untersucht. Wir verwendeten eine Eintopf Sol-Gel-Ansatz, um Gold-Nanopartikeln in den Wänden der mesoporösen Siliciumdioxid einlagern. Mit der Synthese zu starten, wurde P123 als Matrize verwendet, um Mizellen zu bilden. Dann wurde TESPTS als Oberflächenmodifizierungsmittel verwendet, um Nanopartikel aus Gold einlagern. Nach diesem Verfahren wurde in TEOS als Siliciumdioxid-Quelle, die eine Polymerisation in saurem Milieu unter zugegeben. Nachdem die hydrothermische Bearbeitung und die Kalzinierung wurde das Endprodukt erworben. Verschiedene Techniken wurden eingesetzt, um die Porosität, die Morphologie und Struktur der Gold interkalierten mesoporösen Siliciumdioxid charakterisieren. Die Ergebnisse zeigten eine stabile Struktur von mesoporösem Siliciumdioxid nach gold Interkalation. Durch die Oxidation von Benzylalkohol als Bezugsreaktion zeigten die GMS Materialien hoher Selecvität und Recyclingfähigkeit.

Dieses Verfahren wurde verwendet, um das Niveau der Häm-Synthese in normal (HBEC30KT) gegen Krebs (HCC4017) Lungenzellen zu vergleichen. 2 zeigt ein höheres Niveau der Häm-Synthese in Krebszellen (HCC4017) als normale Lungenzellen (HBEC30KT). Das Niveau der Häm-Synthese wurde auch in normalen Zellen und Krebszellen in Gegenwart von mitochondrialen Entkoppler Carbonylcyanid 3-chlorphenylhydrazon (CCCP) gemessen. Zellen wurden mit 10 uM CCCP 24 h vor der Messung Hämsynthese Ebenen behandelt. Wie erwa...

Watch this Scientific Journal Video about Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica at JoVE.com

Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

Synthese und katalytische Aktivität von Gold-Intercalated in den Wänden der mesoporösen Silicat-

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties ...

synthesis-catalytic-performance-gold-intercalated-walls-mesoporous

Research

JoVE Journal

Chemistry

10.0K Aufrufe.  Colorado School of Mines. Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

Serie: Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

Preparation of Silica Nanoparticles Through Microwave-assisted Acid-catalysis

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle diameters ranging from 30-250 nm by varying the reaction conditions. Through the selection of a microwave compatible solvent, silicic acid precursor, catalyst, and microwave irradiation time, these microwave-assisted methods were capable of overcoming the previously reported shortcomings associated with synthesis of silica nanoparticles using microwave reactors. The siloxane precursor was hydrolyzed using the acid catalyst, HCl. Acetone, a low-tan &#948; solvent, mediates the condensation reactions and has minimal interaction with the electromagnetic field. Condensation reactions begin when the silicic acid precursor couples with the microwave radiation, leading to silica nanoparticle sol formation. The silica nanoparticles were characterized by dynamic light scattering data and scanning electron microscopy, which show the materials&#39; morphology and size to be dependent on the reaction conditions. Microwave-assisted reactions produce silica nanoparticles with roughened textured surfaces that are atypical for silica sols produced by St&#246;ber&#39;s methods, which have smooth surfaces.

Silica nanoparticles were prepared using acid-catalysis of a siloxane precursor and microwave-assisted synthetic techniques resulting in the controlled growth of nanomaterials ranging from 30-250 nm in diameter. The growth dynamics can be controlled by varying the initial silicic acid concentration, time of the reaction, and temperature of reaction.

Herstellung von Silica-Nanopartikeln durch Mikrowellen-unterstützte Säure-Katalyse

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle ...

Forschung

Chemie

In Situ SIMS and IR Spectroscopy of Well-defined Surfaces Prepared by Soft Landing of Mass-selected Ions

Soft landing of mass-selected ions onto surfaces is a powerful approach for the highly-controlled preparation of materials that are inaccessible using conventional synthesis techniques. Coupling soft landing with in situ characterization using secondary ion mass spectrometry (SIMS) and infrared reflection absorption spectroscopy (IRRAS) enables analysis of well-defined surfaces under clean vacuum conditions. The capabilities of three soft-landing instruments constructed in our laboratory are illustrated for the representative system of surface-bound organometallics prepared by soft landing of mass-selected ruthenium tris(bipyridine) dications, [Ru(bpy)3]2+ (bpy = bipyridine), onto carboxylic acid terminated self-assembled monolayer surfaces on gold (COOH-SAMs). In situ time-of-flight (TOF)-SIMS provides insight into the reactivity of the soft-landed ions. In addition, the kinetics of charge reduction, neutralization and desorption occurring on the COOH-SAM both during and after ion soft landing are studied using in situ Fourier transform ion cyclotron resonance (FT-ICR)-SIMS measurements. In situ IRRAS experiments provide insight into how the structure of organic ligands surrounding metal centers is perturbed through immobilization of organometallic ions on COOH-SAM surfaces by soft landing. Collectively, the three instruments provide complementary information about the chemical composition, reactivity and structure of well-defined species supported on surfaces.

In Situ SIMS and IR Spectroscopy of Well-defined Surfaces Prepared by Soft Landing of Mass-selected Ions

Soft landing of mass-selected ions onto surfaces is a powerful approach for the highly-controlled preparation of novel materials. Coupled with analysis by in situ secondary ion mass spectrometry (SIMS) and infrared reflection absorption spectroscopy (IRRAS), soft landing provides unprecedented insights into the interactions of well-defined species with surfaces.

In-situ-SIMS und IR-Spektroskopie von gut definierten Oberflächen durch weiche Landung der Messe-Ionen ausgewählt Vorbereitet

Soft landing of mass-selected ions onto surfaces is a powerful approach for the highly-controlled preparation of materials that are inaccessible using ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

Synthese, Charakterisierung und Funktionalisierung von Hybrid Au / CdS und Au / ZnS Kern / Schale-Nanopartikel

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the first, synthesis of ultra-small copper nanoclusters is described. The second example provides their utility for investigating time resolved kinetics of chemical reactions by analyzing gold nanoparticle formation using in situ X-ray absorption spectroscopy. The final example demonstrates continuous flow catalysis of reactions inside millifluidic channel coated with nanostructured catalyst.

Millifluidic devices are utilized for controlled synthesis of nanomaterials, time-resolved analysis of reaction mechanisms and continuous flow catalysis.

Millifluidics für Chemische Synthese und Zeitaufgelöste mechanistische Studien

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the ...

Biotechnik

In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films

Combinations of metal oxide semiconductors and gold nanoparticles (AuNPs) have been investigated as new types of materials. The in situ synthesis of AuNPs within the interlayer space of semiconducting layered titania nanosheet (TNS) films was investigated here. Two types of intermediate films (i.e., TNS films containing methyl viologen (TNS/MV2+) and 2-ammoniumethanethiol (TNS/2-AET+)) were prepared. The two intermediate films were soaked in an aqueous tetrachloroauric(III) acid (HAuCl4) solution, whereby considerable amounts of Au(III) species were accommodated within the interlayer spaces of the TNS films. The two types of obtained films were then soaked in an aqueous sodium tetrahydroborate (NaBH4) solution, whereupon the color of the films immediately changed from colorless to purple, suggesting the formation of AuNPs within the TNS interlayer. When only TNS/MV2+ was used as the intermediate film, the color of the film gradually changed from metallic purple to dusty purple within 30 min, suggesting that aggregation of AuNPs had occurred. In contrast, this color change was suppressed by using the TNS/2-AET+ intermediate film, and the AuNPs were stabilized for over 4 months, as evidenced by the characteristic extinction (absorption and scattering) band from the AuNPs.

In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films

Here, we present a protocol for the in situ synthesis of gold nanoparticles (AuNPs) within the interlayer space of layered titanate films without the aggregation of AuNPs. No spectral change was observed even after 4 months. The synthesized material has expected applications in catalysis, photo-catalysis, and the development of cost-effective plasmonic devices.

In - situ - Synthese von Gold - Nanopartikeln ohne Aggregation zwischen die Schichten von Layered - Titanat OHP - Folien

Combinations of metal oxide semiconductors and gold nanoparticles (AuNPs) have been investigated as new types of materials. The in situ synthesis of AuNPs ...

Ingenieurwesen

Preparation of Functional Silica Using a Bioinspired Method

The goal of the protocols described herein is to synthesize bioinspired silica materials, perform enzyme encapsulation therein, and partially or totally purify the same by acid elution. By combining sodium silicate with a polyfunctional bioinspired additive, silica is rapidly formed at ambient conditions upon neutralization. 
The effect of neutralization rate and biomolecule addition point on silica yield are investigated, and biomolecule immobilization efficiency is reported for varying addition point. In contrast to other porous silica synthesis methods, it is shown that the mild conditions required for bioinspired silica synthesis are fully compatible with the encapsulation of delicate biomolecules. Additionally, mild conditions are used across all synthesis and modification steps, making bioinspired silica a promising target for the scale-up and commercialization as both a bare material and active support medium.
The synthesis is shown to be highly sensitive to conditions, i.e., the neutralization rate and final synthesis pH, however tight control over these parameters is demonstrated through the use of auto titration methods, leading to high reproducibility in reaction progression pathway and yield. 
Therefore, bioinspired silica is an excellent active material support choice, showing versatility towards many current applications, not limited to those demonstrated here, and potency in future applications.

Here, we present a protocol to synthesize bioinspired silica materials and immobilize enzymes therein. Silica is synthesized by combining sodium silicate and an amine &#39;additive&#39;, which neutralize at a controlled rate. Material properties and function can be altered either by in situ enzyme immobilization or post-synthetic acid elution of encapsulated additives.

Vorbereitung der funktionalen Kieselsäure mit einer Muskelmodelle Methode

The goal of the protocols described herein is to synthesize bioinspired silica materials, perform enzyme encapsulation therein, and partially or totally ...

A Rapid Synthesis Method for Au, Pd, and Pt Aerogels Via Direct Solution-Based Reduction

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various precursor noble metal ions with reducing agents in a 1:1 (v/v) ratio results in the formation of metal gels within seconds to minutes compared to much longer synthesis times for other techniques such as sol-gel. Conducting the reduction step in a microcentrifuge tube or small volume conical tube facilitates a proposed nucleation, growth, densification, fusion, equilibration model for gel formation, with final gel geometry smaller than the initial reaction volume. This method takes advantage of the vigorous hydrogen gas evolution as a by-product of the reduction step, and as a consequence of reagent concentrations. The solvent accessible specific surface area is determined with both electrochemical impedance spectroscopy and cyclic voltammetry. After rinsing and freeze drying, the resulting aerogel structure is examined with scanning electron microscopy, X-ray diffractometry, and nitrogen gas adsorption. The synthesis method and characterization techniques result in a close correspondence of aerogel ligament sizes. This synthesis method for noble metal aerogels demonstrates that high specific surface area monoliths may be achieved with a rapid and direct reduction approach.

A rapid, direct solution-based reduction synthesis method to obtain Au, Pd, and Pt aerogels is presented.

Eine schnelle Synthese-Methode für Au, Pd und Pt-Aerogelen über lösungsorientierte Direktreduktion

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various ...

Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices

In this work, we report the synthesis and characterization of ordered nanoporous carbon material (also called ordered mesoporous carbon material [OMC]) with a 4.6 nm pore size, and ordered silica porous matrix, SBA-15, with a 5.3 nm pore size. This work describes the surface properties of nanoporous molecular sieves, their wettability, and the melting behavior of D2O confined in the differently ordered porous materials with similar pore sizes. For this purpose, OMC and SBA-15 with highly ordered nanoporous structures are synthesized via impregnation of the silica matrix by applying a carbon precursor and by the sol-gel method, respectively. The porous structure of investigated systems is characterized by an N2 adsorption-desorption analysis at 77 K. To determine the electrochemical character of the surface of synthesized materials, potentiometric titration measurements are conducted; the obtained results for OMC shows a significant pHpzc shift toward the higher values of pH, relative to SBA-15. This suggests that investigated OMC has surface properties related to oxygen-based functional groups. To describe the surface properties of the materials, the contact angles of liquids penetrating the studied porous beds are also determined. The capillary rise method has confirmed the increased wettability of the silica walls relative to the carbon walls and an influence of the pore roughness on the fluid/wall interactions, which is much more pronounced for silica than for carbon mesopores. We have also studied the melting behavior of D2O confined in OMC and SBA-15 by applying the dielectric method. The results show that the depression of the melting temperature of D2O in the pores of OMC is about 15 K higher relative to the depression of the melting temperature in SBA-15 pores with a comparable 5 nm size. This is caused by the influence of adsorbate/adsorbent interactions of the studied matrices.

Here we report the synthesis and characterization of ordered nanoporous carbon (with a 4.6 nm pore size) and SBA-15 (with a 5.3 nm pore size). The work describes the surface and textural properties of nanoporous molecular sieves, their wettability, and the melting behavior of D2O confined in the materials.

Oberflächeneigenschaften von synthetisierten nanoporöse Carbon und Silica-Matrizen

In this work, we report the synthesis and characterization of ordered nanoporous carbon material (also called ordered mesoporous carbon material [OMC]) ...

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

With this protocol, a well-defined singlesite silica-supported heterogeneous catalyst [(&#8801;Si-O-)Hf(=NMe)(&#951;1-NMe2)] is designed and prepared according to the methodology developed by surface organometallic chemistry (SOMC). In this framework, catalytic cycles can be determined by isolating crucial intermediates. All air-sensitive materials are handled under inert atmosphere (using gloveboxes or a Schlenk line) or high vacuum lines (HVLs, &#60;10-5 mbar). The preparation of SiO2-700 (silica dehydroxylated at 700 &#176;C) and subsequent applications (the grafting of complexes and catalytic runs) requires the use of HVLs and double-Schlenk techniques. Several well-known characterization methods are used, such as Fourier-transform infrared spectroscopy (FTIR), elemental microanalysis, solid-state nuclear magnetic resonance spectroscopy (SSNMR), and state-of-the-art dynamic nuclear polarization surface enhanced NMR spectroscopy (DNP-SENS). FTIR and elemental microanalysis permit scientists to establish the grafting and its stoichiometry. 1H and 13C SSNMR allows the structural determination of the hydrocarbon ligands coordination sphere. DNP SENS is an emerging powerful technique in solid characterization for the detection of poorly sensitive nuclei (15N, in our case). SiO2-700 is treated with about one equivalent of the metal precursor compared to the amount of surface silanol (0.30 mmol&#183;g-1) in pentane at room temperature. Then, volatiles are removed, and the powder samples are dried under dynamic high vacuum to afford the desired materials [(&#8801;Si-O-)Hf(&#951;2&#960;-MeNCH2)(&#951;1-NMe2)(&#951;1-HNMe2)]. After a thermal treatment under high vacuum, the grafted complex is converted into metal imido silica complex [(&#8801;Si-O-)Hf(=NMe)(&#951;1-NMe2)]. [(&#8801;Si-O-)Hf(=NMe)(&#951;1-NMe2)] effectively promotes the metathesis of imines, using the combination of two imine substrates, N-(4-phenylbenzylidene)benzylamine, or N-(4-fluorobenzylidene)-4-fluoroaniline, with N-benzylidenetert-butylamine as substrates. A significantly lower conversion is observed with the blank runs; thus, the presence of the imido group in [(&#8801;Si-O-)Hf(=NMe)(&#951;1-NMe2)] is correlated to the catalytic performance.

A new group IV metal catalyst for imine metathesis is prepared by grafting amine metal complex onto dehydroxylated silica. Surface metal fragments are characterized using FT-IR, elemental microanalysis, and solid-state NMR spectroscopy. Further dynamic nuclear polarization surface enhanced NMR spectroscopy experiments complement the determination of the coordination sphere.

Imine Metathesis von Silica-unterstützten Katalysatoren mit der Methodik der Oberflächenorganometallischen Chemie

With this protocol, a well-defined singlesite silica-supported heterogeneous catalyst [(&#8801;Si-O-)Hf(=NMe)(&#951;1-NMe2)] is designed and prepared ...

A Salt-Templated Synthesis Method for Porous Platinum-based Macrobeams and Macrotubes

The synthesis of high surface area porous noble metal nanomaterials generally relies on time consuming coalescence of pre-formed nanoparticles, followed by rinsing and supercritical drying steps, often resulting in mechanically fragile materials. Here, a method to synthesize nanostructured porous platinum-based macrotubes and macrobeams with a square cross section from insoluble salt needle templates is presented. The combination of oppositely charged platinum, palladium, and copper square planar ions results in the rapid formation of insoluble salt needles. Depending on the stoichiometric ratio of metal ions present in the salt-template and the choice of chemical reducing agent, either macrotubes or macrobeams form with a porous nanostructure comprised of either fused nanoparticles or nanofibrils. Elemental composition of the macrotubes and macrobeams, determined with x-ray diffractometry and x-ray photoelectron spectroscopy, is controlled by the stoichiometric ratio of metal ions present in the salt-template. Macrotubes and macrobeams may be pressed into free standing films, and the electrochemically active surface area is determined with electrochemical impedance spectroscopy and cyclic voltammetry. This synthesis method demonstrates a simple, relatively fast approach to achieve high-surface area platinum-based macrotubes and macrobeams with tunable nanostructure and elemental composition that may be pressed into free-standing films with no required binding materials.

A synthesis method to obtain porous platinum-based macrotubes and macrobeams with a square cross section through chemical reduction of insoluble salt-needle templates is presented.

Eine salzgemusterte Synthesemethode für poröse Platin-basierte Makrostrahlen und Makroröhren

The synthesis of high surface area porous noble metal nanomaterials generally relies on time consuming coalescence of pre-formed nanoparticles, followed ...