Reconhecemos a Virginia Military Institute (VMI) Departamento de Química para o apoio de ensaios eletroquímicos e instrumentação (LSC e JTH). O Gabinete de VMI do Director da Faculdade suportado custos de produção associados com publicações JoVE. Reconhecemos a UNC EFRC: Centro de Combustíveis solares, um Centro de Pesquisa de Energia Frontier financiado pelo Departamento de Energia, Secretaria de Ciência, Instituto de ciências básicas da energia sob Award Número DE-SC0001011, dos Estados Unidos para o apoio da síntese de compostos e caracterização de materiais (DPH ).

1. Synthesize 1 Sintetizar 1 (PhTpy é 4&#39;-fenil-2,2 &#39;: 6&#39;, 2 &#39;&#39; - terpyridine; 5,5&#39;-dvbpy é 5,5&#39;-divinil-2,2&#39;-bipiridina; Figura 4) de acordo com a o procedimento descrito anteriormente. 18 2. Preparar a 1,3 mM de uma solução de monómero de uma solução de electrólito <ol><li> Prepare uma solução eletrolítica 0,1 M estoque de tetra hexafluorophosphate n butilamónio, TBAPF 6, em acetonitrila, MeCN. <ol><li> Coloque MeCN sobre ativado 3 peneiras moleculares A ou K 2 CO 3, durante 24 horas para remover H 2 O. acidental </li><li> Coloque TBAPF 6 (0,969 g, 2,50 mmol) em 25,00 ml de um frasco seco à chama volumétrico. </li><li> Filtra-se o peneiro molecular ou K 2 CO 3 a partir de partículas de MeCN seco e trazer a 25,00 ml balão volumétrico contendo TBAPF <sub&gt; 6 para volume. </li></ol></li><li> Colocar 1 (0,0049 g, 5,2 x 10 -6 mol) em seco e 4 dram frasco ou um balão de fundo redondo de 10 ml e adicionar 4,00 ml da solução de estoque de 0,1 M em MeCN TBAPF 6. </li><li> Transferir 3,5-4,0 ml da solução electrolítica de cor vermelha-laranja de 1 para o compartimento central de uma célula de três compartimentos, com cada compartimento separado por uma frita de vidro de porosidade média. </li><li> Rapidamente encher os compartimentos exteriores da célula de 3 compartimentos de uma altura igual como a solução estoque compartimento central, com alguns dos restantes anidra 0,1 M em MeCN TBAPF 6 para evitar a fuga para os compartimentos exteriores. Nota: O tempo é um factor importante, pois as soluções nos diferentes compartimentos irá misturar lentamente e alterar significativamente a concentração do compartimento principal se as alturas de solventes não são o mesmo. </li></ol> 3. Electropolymerize 1 sobre um vidro 3 mm de diâmetroy Carbono Eletrodo ou de 1,0 cm 2 FTO Eletrodo <ol><li> Prepare septos para tubos de desgaseificação de nitrogênio / argônio e para os eletrodos. <ol><li> Cortar uma fenda em cada um dos septos de borracha 3 e guiar uma fina politetrafluoroetileno, PTFE, tubo através da fenda. </li><li> Deslize o eléctrodo 3 de referência de Ag / AgNO através de um dos septos, colocar o eléctrodo de referência / tubo de PTFE / septo em um dos compartimentos exteriores, e selar o compartimento com o septo. </li><li> Guiar o contador eléctrodo de fio de platina / gaze através de um septo lugar diferente do fio de platina / tubo de PTFE / septo em um dos compartimentos exteriores, e selar o compartimento com o septo. Se a fenda não é suficientemente grande ou fio suficientemente rígido para evitar a dobragem do fio, utilizar uma agulha de calibre grande para guiar o contador eléctrodo de fio de platina através do septo. </li><li> Guia de 3 mm em eletrodo de carbono vítreo recém polida através do septo restante e coloque-o de tal forma que o eletrodo é suspeNDED na solução ou, para um slide de FTO, guiar um fio ligado a um jacaré através do septo, em seguida, apertar o slide FTO com o jacaré e certifique-se de que o lado condutora do slide é perpendicular ao eléctrodo contador quando submersa . <ol><li> Antes de inserir o eletrodo de carbono vítreo: o polonês de carbono vítreo, colocando alumina (0,5 mm) em uma almofada de polimento molhado, então, mova o eletrodo em uma figura-8 movimento por 30 segundos, mantendo o eletrodo perpendicular ao pad - para polonês todos os lados do eléctrodo uniformemente - enxaguar e qualquer remanescente de alumina com um H2O garrafa de esguicho de água seguido por uma garrafa de esguicho de lavagem de MeCN. </li><li> Antes de prender a corrediça FTO: envolver diversas camadas de fita não condutor Kapton em torno da parte central de um 30 x 10 mm FTO corrediça de tal modo que uma porção de 10 x 10 mm de, a lâmina é exposta. </li><li> Colete um espectro UV-Vis do slide FTO, colocando / segurando o slide FTO em um postuladoíon no caminho do feixe do espectrômetro que foi pré-determinado para garantir a consistência. </li></ol></li></ol></li><li> Purgar as soluções na célula electroquímica de 3 compartimentos. <ol><li> Conecte uma extremidade do tubo Tygon ao azoto / fornecimento de argônio e conecte a outra extremidade a um lavador de gases contendo MeCN. </li><li> Corte outro pedaço de tubo Tygon, conecte uma extremidade à outflowing MeCN lavado nitrogênio / argônio, e conecte a outra extremidade a um 4 way splitter. </li><li> Ligue os tubos de PTFE aos 3 conexões restantes do 4 way splitter. </li><li> Submergir os tubos de PTFE para as soluções em cada um dos compartimentos e ligar o fluxo de azoto / árgon tal que uma rápida borbulhar da solução começa. </li><li> Continuar de-gaseificar a solução para 5-10 min, em seguida, puxar os tubos de PTFE apenas acima da superfície da solução, deixando o fluxo de azoto / árgon na, a fim de manter uma pressão positiva de gás inerte sobre o sistema e para impedir que a solução convection causada por borbulhamento. </li></ol></li><li> Realizar ensaios eletroquímicos. <ol><li> Conectar eléctrodos do potenciostato aos eléctrodos apropriados na célula de 3 compartimentos. </li><li> Realize uma voltametria cíclica, CV, experiência com os seguintes parâmetros: potencial de comutação = 0 V e -1,81 V; digitalização / velocidade de varredura = 100 mV / seg; = número de ciclos de cinco. </li><li> Quando o experimento CV está completa, remover o (carbono vítreo ou FTO) eléctrodo de trabalho a partir da polimerização em solução e suavemente enxaguar a superfície do eléctrodo com MeCN a partir de uma pipeta ou uma garrafa de esguicho para remover qualquer solução de monómero remanescente. </li></ol></li></ol> Cobertura Determinação 4. Superfície <ol><li> Inserir o eléctrodo de trabalho enxaguada numa solução recentemente preparada de 0,1 M TBAPF 6 / MeCN em uma célula electroquímica contendo um contra-eléctrodo e um eléctrodo de referência (de preferência o mesmo eléctrodo de referência utilizado no electropolymerization). </li><li> Realize uma voltametria cíclica, CV, experiência com os seguintes parâmetros: potenciais de comutação = 0 e 1,5 V; digitalização / velocidade de varredura = 100 mV / seg; = número de ciclos 15. </li><li> Integrar a carga sob os anódicos e catódicos picos para o electropolymer adsorvida Ru (III / II) pares, em média, a carga sob a anodic e picos catódicos, e usando a Equação 1 determinar a cobertura da superfície. </li><li> Para a corrediça FTO: local / segurar a corrediça FTO na posição predeterminada na frente do suporte da amostra de UV-Vis de tal modo que o percurso do feixe passa através da película colorida. O slide FTO pode ser molhado ou seco, mas fazer comparações sob as mesmas condições que os espectros em branco foi recolhido sob. </li><li> Subtrair o espectro obtido para o espectro FTO que foi recolhido para o slide particular, antes de electropolimerização do espectro do filme-em-FTO, a fim de produzir um espectro de absorção para o próprio filme. </li></ol>

<ol>
	<li>Abru&#241;a, H. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coordination+chemistry+in+two+dimensions:+chemically+modified+electrodes.">Coordination chemistry in two dimensions: chemically modified electrodes.</a> Coordination Chemistry Reviews. 86, 135-189 (1988).</li><li>Waltman, R. J., Bargon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrically+conducting+polymers:+a+review+of+the+electropolymerization+reaction,+of+the+effects+of+chemical+structure+on+polymer+film+properties,+and+of+applications+towards+technology.">Electrically conducting polymers: a review of the electropolymerization reaction, of the effects of chemical structure on polymer film properties, and of applications towards technology.</a> Canadian Journal of Chemistry. 64, 76-95 (1986).</li><li>Zhong, Y. -. W., Yao, C. -. J., Nie, H. -. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electropolymerized+films+of+vinyl-substituted+polypyridine+complexes:+Synthesis,+characterization,+and+applications.">Electropolymerized films of vinyl-substituted polypyridine complexes: Synthesis, characterization, and applications.</a> Coordination Chemistry Reviews. 257, 1357-1372 (2013).</li><li>Bard, A. J., Faulkner, L. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Electrochemical Methods Fundamentals and Applications. , (1980).</li><li>Ramos Sende, J. 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=Electrocatalysis+of+CO2+Reduction+in+Aqueous+Media+at+Electrodes+Modified+with+Electropolymerized+Films+of+Vinylterpyridine+Complexes+of+Transition+Metals.">Electrocatalysis of CO2 Reduction in Aqueous Media at Electrodes Modified with Electropolymerized Films of Vinylterpyridine Complexes of Transition Metals.</a> Inorganic Chemistry. 34, 3339-3348 (1995).</li><li>Cosnier, S., Deronzier, A., Moutet, 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=Electrochemical+coating+of+a+platinum+electrode+by+a+poly(pyrrole)+film+containing+the+fac-Re(2,2'-bipyridine)(CO)3Cl+system+application+to+electrocatalytic+reduction+of+CO2.">Electrochemical coating of a platinum electrode by a poly(pyrrole) film containing the fac-Re(2,2'-bipyridine)(CO)3Cl system application to electrocatalytic reduction of CO2.</a> Journal of Electroanalytical Chemistry and Interfacial Electrochemistry. 207, 315-321 (1986).</li><li>Cosnier, S., Deronzier, A., Moutet, 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=Electrocatalytic+reduction+of+CO2+on+electrodes+modified+by+fac-Re(2,2'-bipyridine)(CO)3Cl+complexes+bonded+to+polypyrrole+films.">Electrocatalytic reduction of CO2 on electrodes modified by fac-Re(2,2'-bipyridine)(CO)3Cl complexes bonded to polypyrrole films.</a> Journal of Molecular Catalysis. 45, 381-391 (1988).</li><li>Toole, T. R., 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=Electrocatalytic+reduction+of+CO2+at+a+chemically+modified+electrode.">Electrocatalytic reduction of CO2 at a chemically modified electrode.</a> Journal of the Chemical Society, Chemical Communications. 20, 1416-1417 (1985).</li><li>Cheung, K. -. C., 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=Ruthenium+Terpyridine+Complexes+Containing+a+Pyrrole-Tagged+2,2&#8242;-Dipyridylamine+Ligand&#8212;Synthesis.">Ruthenium Terpyridine Complexes Containing a Pyrrole-Tagged 2,2&#8242;-Dipyridylamine Ligand&#8212;Synthesis.</a> Crystal Structure, and Electrochemistry. Inorganic Chemistry. 51, 6468-6475 (2012).</li><li>Ashford, D. 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+Oxidation+by+an+Electropolymerized+Catalyst+on+Derivatized+Mesoporous+Metal+Oxide+Electrodes.">Water Oxidation by an Electropolymerized Catalyst on Derivatized Mesoporous Metal Oxide Electrodes.</a> Journal of the American Chemical Society. 136, 6578-6581 (2014).</li><li>Abru&#241;a, H. D., Denisevich, P., Umana, M., Meyer, T. J., Murray, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rectifying+interfaces+using+two-layer+films+of+electrochemically+polymerized+vinylpyridine+and+vinylbipyridine+complexes+of+ruthenium+and+iron+on+electrodes.">Rectifying interfaces using two-layer films of electrochemically polymerized vinylpyridine and vinylbipyridine complexes of ruthenium and iron on electrodes.</a> Journal of the American Chemical Society. 103, 1-5 (1981).</li><li>Gould, S., Gray, K. H., Linton, R. W., Meyer, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microstructures+in+thin+polymeric+films.+Photochemically+produced+molecular+voids.">Microstructures in thin polymeric films. Photochemically produced molecular voids.</a> Inorganic Chemistry. 31, 5521-5525 (1992).</li><li>Devenney, M., 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=Excited+State+Interactions+in+Electropolymerized+Thin+Films+of+Ru(II).">Excited State Interactions in Electropolymerized Thin Films of Ru(II).</a> Os(II), and Zn(II) Polypyridyl Complexes. The Journal of Physical Chemistry A. 101, 4535-4540 (1997).</li><li>Moss, J. 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=Sensitization+and+Stabilization+of+TiO2+Photoanodes+with+Electropolymerized+Overlayer+Films+of+Ruthenium+and+Zinc+Polypyridyl+Complexes:+A+Stable+Aqueous+Photoelectrochemical+Cell.">Sensitization and Stabilization of TiO2 Photoanodes with Electropolymerized Overlayer Films of Ruthenium and Zinc Polypyridyl Complexes: A Stable Aqueous Photoelectrochemical Cell.</a> Inorganic Chemistry. 43, 1784-1792 (2004).</li><li>Yang, J., Sykora, M., Meyer, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Electropolymerization of Vinylbipyridine Complexes of Ruthenium(II) and Osmium(II) in SiO2 Sol&#8722;Gel Films. Inorganic Chemistry. 44, 3396-3404 (2005).</li><li>Nie, H. -. J., Shao, J. -. Y., Wu, J., Yao, J., Zhong, Y. -. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+Reductive+Electropolymerization+of+Metal+Complexes+with+5,5&#8242;-Divinyl-2,2&#8242;-Bipyridine.">Synthesis and Reductive Electropolymerization of Metal Complexes with 5,5&#8242;-Divinyl-2,2&#8242;-Bipyridine.</a> Organometallics. 31, 6952-6959 (2012).</li><li>Yao, C. -. J., Zhong, Y. -. W., Nie, H. -. J., Abru&#241;a, H. D., Yao, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Near-IR+Electrochromism+in+Electropolymerized+Films+of+a+Biscyclometalated+Ruthenium+Complex+Bridged+by+1,2,4,5-Tetra(2-pyridyl)benzene.">Near-IR Electrochromism in Electropolymerized Films of a Biscyclometalated Ruthenium Complex Bridged by 1,2,4,5-Tetra(2-pyridyl)benzene.</a> Journal of the American Chemical Society. 133, 20720-20723 (2011).</li><li>Harrison, D. P., 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=Coordination+Chemistry+of+Single-Site+Catalyst+Precursors+in+Reductively+Electropolymerized+Vinylbipyridine+Films.">Coordination Chemistry of Single-Site Catalyst Precursors in Reductively Electropolymerized Vinylbipyridine Films.</a> Inorganic Chemistry. 52, 4747-4749 (2013).</li><li>Calvert, J. M., 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=Synthetic+and+mechanistic+investigations+of+the+reductive+electrochemical+polymerization+of+vinyl-containing+complexes+of+iron(II),+ruthenium(II),+and+osmium(II).">Synthetic and mechanistic investigations of the reductive electrochemical polymerization of vinyl-containing complexes of iron(II), ruthenium(II), and osmium(II).</a> Inorganic Chemistry. 22, 2151-2162 (1983).</li><li>Moss, J. A., Argazzi, R., Bignozzi, C. A., Meyer, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electropolymerization+of+Molecular+Assemblies.">Electropolymerization of Molecular Assemblies.</a> Inorganic Chemistry. 36, 762-763 (1997).</li><li>Deronzier, A., Eloy, D., Jardon, P., Martre, A., Moutet, 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=Electroreductive+coating+of+electrodes+from+soluble+polypyrrole-ruthenium+(II)+complexes:+ion+modulation+effects+on+their+electroactivity.">Electroreductive coating of electrodes from soluble polypyrrole-ruthenium (II) complexes: ion modulation effects on their electroactivity.</a> Journal of Electroanalytical Chemistry. 453, 179-185 (1998).</li><li>Mola, 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=Ru-Hbpp-Based+Water-Oxidation+Catalysts+Anchored+on+Conducting+Solid+Supports.">Ru-Hbpp-Based Water-Oxidation Catalysts Anchored on Conducting Solid Supports.</a> Angewandte Chemie International Edition. 47, 5830-5832 (2008).</li><li>Deronzier, A., Moutet, 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=Polypyrrole+films+containing+metal+complexes:+syntheses+and+applications.">Polypyrrole films containing metal complexes: syntheses and applications.</a> Coordination Chemistry Reviews. 147, 339-371 (1996).</li><li>Sabouraud, G., Sadki, S., Brodie, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanisms+of+pyrrole+electropolymerization.">The mechanisms of pyrrole electropolymerization.</a> Chemical Society Review. 29, 283-293 (2000).</li><li>Denisevich, P., Abru&#241;a, H. D., Leidner, C. R., Meyer, T. J., Murray, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electropolymerization+of+vinylpyridine+and+vinylbipyridine+complexes+of+iron+and+ruthenium:+homopolymers,+copolymers,+reactive+polymers.">Electropolymerization of vinylpyridine and vinylbipyridine complexes of iron and ruthenium: homopolymers, copolymers, reactive polymers.</a> Inorganic Chemistry. 21, 2153-2161 (1982).</li><li>Younathan, J. N., Wood, K. S., Meyer, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrocatalytic+reduction+of+nitrite+and+nitrosyl+by+iron(III)+protoporphyrin+IX+dimethyl+ester+immobilized+in+an+electropolymerized+film.">Electrocatalytic reduction of nitrite and nitrosyl by iron(III) protoporphyrin IX dimethyl ester immobilized in an electropolymerized film.</a> Inorganic Chemistry. 31, 3280-3285 (1992).</li><li>Ikeda, T., Schmehl, R., Denisevich, P., Willman, K., Murray, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Permeation+of+electroactive+solutes+through+ultrathin+polymeric+films+on+electrode+surfaces.">Permeation of electroactive solutes through ultrathin polymeric films on electrode surfaces.</a> Journal of the American Chemical Society. 104, 2683-2691 (1982).</li><li>Concepcion, J. 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=Making+Oxygen+with+Ruthenium+Complexes.">Making Oxygen with Ruthenium Complexes.</a> Accounts of Chemical Research. 42, 1954-1965 (2009).</li><li>Chen, Z., Concepcion, J. J., Jurss, J. W., Meyer, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-Site,+Catalytic+Water+Oxidation+on+Oxide+Surfaces.">Single-Site, Catalytic Water Oxidation on Oxide Surfaces.</a> Journal of the American Chemical Society. 131, 15580-15581 (2009).</li><li>Lapides, A. M., 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=Stabilization+of+a+Ruthenium(II)+Polypyridyl+Dye+on+Nanocrystalline+TiO2+by+an+Electropolymerized+Overlayer.">Stabilization of a Ruthenium(II) Polypyridyl Dye on Nanocrystalline TiO2 by an Electropolymerized Overlayer.</a> Journal of the American Chemical Society. 135, 15450-15458 (2013).</li><li>Paulson, S. C., Sapp, S. A., Elliott, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemical+and+Spectroelectrochemical+Investigations+into+the+Nature+of+Charge-Trapping+in+Electrochemically-Generated+Homopolymer+Films+of+Tris(4-vinyl-4&#8216;-methyl-2,2&#8216;-bipyridine)ruthenium(II).">Electrochemical and Spectroelectrochemical Investigations into the Nature of Charge-Trapping in Electrochemically-Generated Homopolymer Films of Tris(4-vinyl-4&#8216;-methyl-2,2&#8216;-bipyridine)ruthenium(II).</a> The Journal of Physical Chemistry B. 105, 8718-8724 (2001).</li><li>Laviron, E., Roullier, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=General+expression+of+the+linear+potential+sweep+voltammogram+for+a+surface+redox+reaction+with+interactions+between+the+adsorbed+molecules:+Applications+to+modified+electrodes.">General expression of the linear potential sweep voltammogram for a surface redox reaction with interactions between the adsorbed molecules: Applications to modified electrodes.</a> J. Electroanal. Chem. Interfacial Electrochem. 115, 65-74 (1980).</li><li>Laviron, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=General+expression+of+the+linear+potential+sweep+voltammogram+in+the+case+of+diffusionless+electrochemical+systems.">General expression of the linear potential sweep voltammogram in the case of diffusionless electrochemical systems.</a> J. Electroanal. Chem. 101, 19-28 (1979).</li><li>Ratcliff, E. L., Jenkins, J. L., Nebesny, K., Armstrong, N. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrodeposited,+&#34;Textured&#34;+Poly(3-hexyl-thiophene)+(e-P3HT)+Films+for+Photovoltaic+Applications.">Electrodeposited, &#34;Textured&#34; Poly(3-hexyl-thiophene) (e-P3HT) Films for Photovoltaic Applications.</a> Chemistry of Materials. 20, 5796-5806 (2008).</li></ol>

No conflicts of interest declared.

Electropolimerização oferece uma ampla gama de variáveis ​​controláveis ​​que não são comuns a outras técnicas. Além das variáveis ​​de reacção padrão como reagente (monómero) de concentração, temperatura, solvente, etc, electropolimerização pode ser adicionalmente controlado por parâmetros da experiência electroquímicos comuns aos métodos electroquímicos. Taxas de CV de digitalização, potenciais de comutação, e número de ciclos afetam a deposição de electropolymers. Por...

Electropolimerização é uma técnica de polimerização que utiliza um potencial aplicado para iniciar a polimerização de precursores monoméricos directamente na superfície de um eléctrodo e tem sido explorada para produzir electroactivo fina e / ou fotoquimicamente polypyridyl filmes activos em superfícies de eléctrodos e semicondutores. 1-4 Eletrocatálise, 5-10 de transferência de elétrons, 11, 12 fotoquímica, 13-16 eletrocromismo, 17 e 18 de coordenação química foram investigadas em filmes eletropolimerizado. Esta técnica foi desenvolvida pela primeira vez na Universidade da Carolina do Norte, em uma colaboração Meyer-Murray para a eletropolimerização do vinil 3, 5, 7, 8, 11-15, 19, 20 e pirrol 6, 9, 21-24 me derivadocomplexos TAL em uma variedade de condução substratos. A Figura 1 apresenta uma série de ligantes baseados piridil comum que, quando coordenou a complexos de metais, têm produzido electropolymers. Em electropolimerização redutiva, electropolimerização de compostos vinílicos contendo ocorre mediante a redução de piridilo ligandos conjugados com grupos vinilo, enquanto funcionalizado com ligandos-pirrole, electropolimerização é iniciada pela oxidação dos radicais pirrole, resultando em electropolimerização oxidativo (Figura 2). Electropolimerização tecnologia foi desenvolvida com o objectivo de proporcionar um método generalizado para unir directamente virtualmente qualquer complexo de metal de transição com qualquer eléctrodo. A versatilidade do método abre a porta para numerosas investigações de electropolymer eléctrodos modificados. Em contraste com outras estratégias de fixação, que envolvem ligação directa para o eléctrodo, a electropolimerização oferece advantage de não necessitar de superfície do eletrodo pré-modificação. . Por isso, pode ser aplicada a qualquer número de substratos condutores, independentemente da sua composição ou morfologia de superfície 4, 10, 25, 26 Esta versatilidade é um resultado da mudança de propriedades físicas como o comprimento de polímero cresce; os monómeros são solúveis na solução electrolitica, mas como a polimerização ea reticulação rigidifies o filme, precipitação e adsorção física da superfície do eléctrodo ocorre (Figura 3). 27 Em comparação com o óxido de carboxilato ligado à superfície, que são instáveis ​​em superfícies de óxido em água, ou complexos derivatizado-fosfonato, que são instáveis ​​a pH elevados, utilizados em pesquisa de combustíveis solar, estas estruturas interfaciais película de eléctrodo de polímero de oferecer a vantagem adicional de estabilidade em uma variedade de materiais, incluindo solventes orgânicos e água sobre uma grande faixa de pH (0-14).28-30 electropolimerização também pode depositar filmes com grandes intervalos de coberturas visíveis da superfície, a partir de sub-monocamada para dezenas ou centenas de equivalentes de monocamada, enquanto estruturas de carboxilato ou derivado-fosfonato complexos de interface estão limitados a coberturas de superfície monocamada. Embora qualquer número de compostos que contêm piridilo e polypyridyl vinil ou de pirrole são capazes de polimerização, [Ru II (PhTpy) (5,5&#39;-dvbpy) (MeCN)] (PF6) 2, (1; PhTpy é 4&#39;-fenil -2,2 &#39;: 6&#39;, 2 &#39;&#39; - terpyridine; 5,5&#39;-dvbpy é 5,5&#39;-divinil-2,2&#39;-bipiridina; Figura 4) irá ser utilizada como um complexo modelo demonstrar electropolimerização redutiva em carbono vítreo e óxido de estanho dopado com flúor, FTO, eletrodos neste relatório. 1 é um exemplo de um precursor electropolymer moderna que tem aplicações potenciais electrocatalíticas e, devido ao seu metal-ligand de transferência de carga, MLCT, espectro de absorção encontra-se na região visível do espectro de luz, pode ser investigada com UV-Vis. 18, 30 Por favor, note que alguns resultados apresentados aqui por 1 já foram publicados em uma forma ligeiramente modificada. 18

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reductive electropolymerization of a vinyl-containing poly-pyridyl complex on glassy carbon and fluorine-doped tin oxide electrodes

Controlável modificação da superfície do eletrodo é importante em um número de campos, especialmente aqueles com aplicações de combustíveis solares. Electropolimerização é uma técnica de modificação de superfície que electrodepósitos um filme polimérico na superfície de um eléctrodo pela utilização de um potencial aplicado para iniciar a polimerização de substratos presentes na camada de Helmholtz. Esta técnica útil foi estabelecido pela primeira vez por uma colaboração Murray-Meyer da Universidade da Carolina do Norte em Chapel Hill no início de 1980 e utilizado para estudar inúmeros fenômenos físicos de filmes contendo complexos inorgânicos como o substrato monomérica. Aqui, destacam-se um procedimento para eletrodos de revestimento com um complexo inorgânico realizando electropolimerização redutora do complexo poli-piridil contendo vinil em carbono vítreo e flúor óxido de estanho dopado eletrodos revestidos. Recomendações sobre configurações de células eletroquímicas e procedimentos de solução de problemas estão incluídos. Embora não explicitly descrito aqui, electropolimerização oxidativa de compostos contendo pirrolo segue procedimentos semelhantes à base de vinil electropolimerização redutora, mas são muito menos sensíveis ao oxigénio e à água.

Electropolymer crescimento é mais facilmente reconhecido quando observado o andamento da experiência CV prescrito (Protocolo de texto PASSO 3.3.2). A Figura 5 exemplifica o crescimento electropolymer numa 0,071 centímetros (3 mm de diâmetro) 2 eléctrodo de carbono vítreo com um. O primeiro ciclo do experimento produz um voltamograma aproximadamente parecida com o que se espera de uma solução de rutênio de concentração semelhante (Figura 5, traço p...

Watch this Scientific Journal Video about Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes at JoVE.com

Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes

A procedure for performing reductive electropolymerization of vinyl-containing compounds onto glassy carbon and fluorine doped tin-oxide coated electrodes is presented. Recommendations on electrochemical cell configurations and troubleshooting procedures are included. Although not explicitly described here, oxidative electropolymerization of pyrrole-containing compounds follows similar procedures to vinyl-based reductive electropolymerization.

Electropolimerização redutiva de um complexo poli-piridil-vinil no Glassy contendo carbono e flúor-dopado com óxido de estanho Eléctrodos

Controllable electrode surface modification is important in a number of fields, especially those with solar fuels applications. Electropolymerization is ...

reductive-electropolymerization-vinyl-containing-poly-pyridyl-complex

Research

JoVE Journal

Chemistry

11.7K visualizações.  Virginia Military Institute. A procedure for performing reductive electropolymerization of vinyl-containing compounds onto glassy carbon and fluorine doped tin-oxide coated electrodes is presented. Recommendations on electrochemical cell configurations and troubleshooting procedures are included. Although not explicitly described here, oxidative electropolymerization of pyrrole-containing compounds follows similar procedures to vinyl-based reductive electropolymerization. 

Vídeo: Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes

Improved In-gel Reductive &#946;-Elimination for Comprehensive O-linked and Sulfo-glycomics by Mass Spectrometry

Separation of proteins by SDS-PAGE followed by in-gel proteolytic digestion of resolved protein bands has produced high-resolution proteomic analysis of biological samples. Similar approaches, that would allow in-depth analysis of the glycans carried by glycoproteins resolved by SDS-PAGE, require special considerations in order to maximize recovery and sensitivity when using mass spectrometry (MS) as the detection method. A major hurdle to be overcome in achieving high-quality data is the removal of gel-derived contaminants that interfere with MS analysis. The sample workflow presented here is robust, efficient, and eliminates the need for in-line HPLC clean-up prior to MS. Gel pieces containing target proteins are washed in acetonitrile, water, and ethyl acetate to remove contaminants, including polymeric acrylamide fragments. O-linked glycans are released from target proteins by in-gel reductive &#946;-elimination and recovered through robust, simple clean-up procedures. An advantage of this workflow is that it improves sensitivity for detecting and characterizing sulfated glycans. These procedures produce an efficient separation of sulfated permethylated glycans from non-sulfated (sialylated and neutral) permethylated glycans by a rapid phase-partition prior to MS analysis, and thereby enhance glycomic and sulfoglycomic analyses of glycoproteins resolved by SDS-PAGE.

Improved In-gel Reductive &amp;#946;-Elimination for Comprehensive O-linked and Sulfo-glycomics by Mass Spectrometry

In order to comprehensively explore the diversity of O-linked glycans, a new procedure for in-gel reductive &#946;-elimination, combined with permethylation and a rapid phase-partition method, is applied to the analysis of O-linked glycans directly released from glycoproteins resolved by SDS-PAGE and amenable to subsequent glycomic analysis by mass spectrometry.

Melhorou em-gel redutivas β-eliminação para Comprehensive O-ligados e sulfo-glycomics por Espectrometria de Massa

Separation of proteins by SDS-PAGE followed by in-gel proteolytic digestion of resolved protein bands has produced high-resolution proteomic analysis of ...

Química

Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films

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

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

Templates atomicamente definidos para crescimento epitaxial do Complexo Óxido Filmes Finos

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

Transport of Surface-modified Carbon Nanotubes through a Soil Column

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, electronics and biomedical applications. Due to their accelerating production and use, CNTs constitute a potential environmental risk if they are released to soil and groundwater systems. It is therefore essential to improve the current understanding of environmental fate and transport of CNTs. The transport and retention of CNTs in both natural and artificial media have been reported in literature, but the findings widely vary and are thus not conclusive. There are a number of physical and chemical parameters responsible for variation in retention and transport. In this study, a complete procedure of selected multiwalled carbon nanotubes (MWCNTs) is presented starting from their surface modification to a complete set of laboratory column experiments at critical physical and chemical scenarios. Results indicate that the stability of the commercially available MWCNTs are critical with their attached surface functional group which can also influence the transport and retention of MWCNT through the surrounding medium.

Surface properties of a nanoparticle are important for their interaction with the surrounding medium. Therefore the surface modification of carbon nanotubes can be critical for their transport and retention through porous media. Here, lab scale column experiments are used to understand the possible transport and retention of these nanoparticles.

Transporte de nanotubos de carbono de superfície modificada através de uma coluna de solo

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

Photochemical Oxidative Growth of Iridium Oxide Nanoparticles on CdSe@CdS Nanorods

We demonstrate a procedure for the photochemical oxidative growth of iridium oxide catalysts on the surface of seeded cadmium selenide-cadmium sulfide (CdSe@CdS) nanorod photocatalysts. Seeded rods are grown using a colloidal hot-injection method and then moved to an aqueous medium by ligand exchange. CdSe@CdS nanorods, an iridium precursor and other salts are mixed and illuminated. The deposition process is initiated by absorption of photons by the semiconductor particle, which results with formation of charge carriers that are used to promote redox reactions. To insure photochemical oxidative growth we used an electron scavenger. The photogenerated holes oxidize the iridium precursor, apparently in a mediated oxidative pathway. This results in the growth of high quality crystalline iridium oxide particles, ranging from 0.5 nm to about 3 nm, along the surface of the rod. Iridium oxide grown on CdSe@CdS heterostructures was studied by a variety of characterization methods, in order to evaluate its characteristics and quality. We explored means for control over particle size, crystallinity, deposition location on the CdS rod, and composition. Illumination time and excitation wavelength were found to be key parameters for such control. The influence of different growth conditions and the characterization of these heterostructures are described alongside a detailed description of their synthesis. Of significance is the fact that the addition of iridium oxide afforded the rods astounding photochemical stability under prolonged illumination in pure water (alleviating the requirement for hole scavengers).

A protocol for the photochemical oxidative growth of small crystalline iridium oxide nanoparticles on the surface of CdSe@CdS seeded rod nanoparticles is presented.

Fotoquímica Crescimento oxidativo da Iridium nanopartículas de óxido de CdSe @ CdS nanobastões

We demonstrate a procedure for the photochemical oxidative growth of iridium oxide catalysts on the surface of seeded cadmium selenide-cadmium sulfide ...

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The composition of heavy crude oils and shale oils varies substantially depending on the origin of the mixture. In particular they contain an increased amount of nitrogen containing compounds compared to the conventionally used sweet crude oils. As nitrogen compounds have an influence on the operation of thermal processes occurring in coker units and steam crackers, and as some species are considered as environmentally hazardous, a detailed analysis of the reactions involving nitrogen containing compounds under pyrolysis conditions provides valuable information. Therefore a novel method has been developed and validated with a feedstock containing a high nitrogen content, i.e., a shale oil. First, the feed was characterized offline by comprehensive two-dimensional gas chromatography (GC &#215; GC) coupled with a nitrogen chemiluminescence detector (NCD). In a second step the on-line analysis method was developed and tested on a steam cracking pilot plant by feeding pyridine dissolved in heptane. The former being a representative compound for one of the most abundant classes of compounds present in shale oil. The composition of the reactor effluent was determined via an in-house developed automated sampling system followed by immediate injection of the sample on a GC &#215; GC coupled with a time-of-flight mass spectrometer (TOF-MS), flame ionization detector (FID) and NCD. A novel method for quantitative analysis of nitrogen containing compounds using NCD and 2-chloropyridine as an internal standard has been developed and demonstrated.

A method combining comprehensive two-dimensional gas chromatography with nitrogen chemiluminescence detection has been developed and applied to on-line analysis of nitrogen containing compounds in a complex hydrocarbon matrix.

Análise on-line de compostos contendo azoto em matrizes de hidrocarbonetos complexos

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The ...

Investigations on the Ga(III) Complex of EOB-DTPA and Its 68Ga Radiolabeled Analogue

We demonstrate a method for the isolation of EOB-DTPA (3,6,9-triaza-3,6,9-tris(carboxymethyl)-4-(ethoxybenzyl)-undecanedioic acid) from its Gd(III) complex and protocols for the preparation of its novel non-radioactive, i.e., natural Ga(III) as well as radioactive 68Ga complex. The ligand as well as the Ga(III) complex were characterized by nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and elemental analysis. 68Ga was obtained by a standard elution method from a 68Ge/68Ga generator. Experiments to evaluate the 68Ga-labeling efficiency of EOB-DTPA at pH 3.8&#8211;4.0 were performed. Established analysis techniques radio TLC (thin layer chromatography) and radio HPLC (high performance liquid chromatography) were used to determine the radiochemical purity of the tracer. As a first investigation of the 68Ga tracers&#39; lipophilicity the n-octanol/water distribution coefficient of 68Ga species present in a pH 7.4 solution was determined by an extraction method. In vitro stability measurements of the tracer in various media at physiological pH were performed, revealing different rates of decomposition.

Investigations on the GaIII Complex of EOB-DTPA and Its 68Ga Radiolabeled Analogue

A procedure for the isolation of EOB-DTPA and subsequent complexation with natural Ga(III) and 68Ga is presented herein, as well as a thorough analysis of all compounds and investigations on labeling efficiency, in vitro stability and the n-octanol/water distribution coefficient of the radiolabeled complex.

As investigações sobre o Complexo Ga (III) de EOB-DTPA e sua<sup&gt; 68</sup&gt; Ga Radiolabeled Analogue

We demonstrate a method for the isolation of EOB-DTPA (3,6,9-triaza-3,6,9-tris(carboxymethyl)-4-(ethoxybenzyl)-undecanedioic acid) from its Gd(III) ...

Grafting Multiwalled Carbon Nanotubes with Polystyrene to Enable Self-Assembly and Anisotropic Patchiness

We demonstrate a straightforward protocol to graft pristine multiwalled carbon nanotubes (MWCNTs) with polystyrene (PS) chains at the sidewalls through a free-radical polymerization strategy to enable the modulation of the nanotube surface properties and produce supramolecular self-assembly of the nanostructures. First, a selective hydroxylation of the pristine nanotubes through a biphasic catalytically mediated oxidation reaction creates superficially distributed reactive sites at the sidewalls. The latter reactive sites are subsequently modified with methacrylic moieties using a silylated methacrylic precursor to create polymerizable sites. Those polymerizable groups can address further polymerization of styrene to produce a hybrid nanomaterial containing PS chains grafted to the nanotube sidewalls. The polymer-graft content, amount of silylated methacrylic moieties introduced and hydroxylation modification of the nanotubes are identified and quantified by Thermogravimetric Analysis (TGA). The presence of reactive functional groups hydroxyl and silylated methacrylate are confirmed by Fourier Transform Infrared Spectroscopy (FT-IR). Polystyrene-grafted carbon nanotube solutions in tetrahydrofuran (THF) provide wall-to-wall collinearly self-assembled nanotubes when cast samples are analyzed by transmission electron microscopy (TEM). Those self-assemblies are not obtained when suitable blanks are similarly cast from analogous solutions containing non-grafted counterparts. Therefore, this method enables the modification of the nanotube anisotropic patchiness at the sidewalls which results into spontaneous auto-organization at the nanoscale.

A procedure for the synthesis of polystyrene-grafted multiwalled carbon nanotubes using successive chemical modification steps to selectively introduce the polymer chains to the sidewalls and their self-assembly via anisotropic patchiness is presented.

Enxertia de nanotubos de carbono de Multiwalled com poliestireno para habilitar auto-montagem e anisotrópica Patchiness

We demonstrate a straightforward protocol to graft pristine multiwalled carbon nanotubes (MWCNTs) with polystyrene (PS) chains at the sidewalls through a ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). In the case of fast reversible electrochemical processes, current is predominantly affected by the rate of diffusion, which is the slowest and limiting stage. EIS is a powerful technique that allows separate analysis of stages of charge transfer that have different AC frequency response. The capability of the method was used to extract the value of charge transfer resistance, which characterizes the rate of charge exchange on the electrode-solution interface. The application of this technique is broad, from biochemistry up to organic electronics. In this work, we are presenting the method of analysis of organic compounds for optoelectronic applications.

Electrochemical impedance spectroscopy (EIS) of species that undergo reversible oxidation or reduction in solution was used for determination of rate constants of oxidation or reduction.

Espectroscopia de impedância eletroquímica como uma ferramenta para estimativa de constante taxa eletroquímica

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Solvothermal Synthesis of MIL-96 and UiO-66-NH2 on Atomic Layer Deposited Metal Oxide Coatings on Fiber Mats

Metal-organic frameworks (MOFs), which contain reactive metal clusters and organic ligands allowing for large porosities and surface areas, have proven effective in gas adsorption, separations, and catalysis. MOFs are most commonly synthesized as bulk powder, requiring additional processes to adhere them to functional devices and fabrics that risk decreasing the powder porosity and adsorption capacity. Here, we demonstrate a method of first coating fabrics with metal oxide films using atomic layer deposition (ALD). This process creates conformal films of controllable thickness on each fiber, while providing a more reactive surface for MOF nucleation. By submerging the ALD coated fabric in solution during solvothermal MOF synthesis, the MOFs create a conformal, well-adhered coating on the fibers, resulting in a MOF-functionalized fabric, without additional adhesion materials that may block MOF pores and functional sites. Here we demonstrate two solvothermal synthesis methods. First, we form a MIL-96(Al) layer on polypropylene fibers using synthetic conditions that convert the metal oxide to MOF. Using initial inorganic films of varying thicknesses, diffusion of the organic linker into the inorganic allows us to control the extent of MOF loading on the fabric. Second, we perform a solvothermal synthesis of UiO-66-NH2 in which the MOF nucleates on the conformal metal oxide coating on polyamide-6 (PA-6) fibers, thereby producing a uniform and conformal thin film of MOF on the fabric. The resulting materials can be directly incorporated into filter devices or protective clothing and eliminate the maladroit qualities of loose powder.

Solvothermal Synthesis of MIL-96 and UiO-66-NH2 on Atomic Layer Deposited Metal Oxide Coatings on Fiber Mats

Metal-organic frameworks are effective in gas storage and heterogeneous catalysis, but typical synthesis methods result in loose powders that are difficult to incorporate into smart materials. We demonstrate a method of first coating fabrics with ALD metal oxides, resulting in conformal films of MOF on the fabrics during solvothermal synthesis.

Síntese de Solvothermal de MIL-96 e UiO-66-NH2 na camada atômica depositado revestimentos de óxido metálico em esteiras de fibra

Metal-organic frameworks (MOFs), which contain reactive metal clusters and organic ligands allowing for large porosities and surface areas, have proven ...

Negative Additive Manufacturing of Complex Shaped Boron Carbides

Boron carbide (B4C) is one of the hardest materials in existence. However, this attractive property also limits its machineability into complex shapes for high wear, high hardness, and lightweight material applications such as armors. To overcome this challenge, negative additive manufacturing (AM) is employed to produce complex geometries of boron carbides at various length scales. Negative AM first involves gelcasting a suspension into a 3D-printed plastic mold. The mold is then dissolved away, leaving behind a green body as a negative copy. Resorcinol-formaldehyde (RF) is used as a novel gelling agent because unlike traditional hydrogels, there is little to no shrinkage, which allows for extremely complex molds to be used. Furthermore, this gelling agent can be pyrolyzed to leave behind ~50 wt% carbon, which is a highly effective sintering aid for B4C. Due to this highly homogenous distribution of in situ carbon within the B4C matrix, less than 2% porosity can be achieved after sintering. This protocol highlights in detail the methodology for creating near fully dense boron carbide parts with highly complex geometries.

A method called negative additive manufacturing is used to produce near fully dense complex shaped boron carbide parts of various length scales. This technique is possible via the formulation of a novel suspension involving resorcinol-formaldehyde as a unique gelling agent that leaves behind a homogenous carbon sintering aid after pyrolysis.

Fabricação aditiva negativa do complexo em forma de carbonetos de boro

Boron carbide (B4C) is one of the hardest materials in existence. However, this attractive property also limits its machineability into complex shapes for ...