{"id":654,"date":"2008-05-22T15:10:56","date_gmt":"2008-05-22T19:10:56","guid":{"rendered":"http:\/\/www.catalysisclubphilly.org\/awe9a91v\/?p=654"},"modified":"2012-10-17T11:47:02","modified_gmt":"2012-10-17T15:47:02","slug":"the-use-of-ultra-high-field-nuclear-magnetic-resonance-spectroscopy-to-study-the-surface-structure-and-catalytic-properties-of-poorly-crystalline-al2o3-surfaces","status":"publish","type":"post","link":"https:\/\/catalysisclubphilly.org\/awe9a91v\/abstracts\/the-use-of-ultra-high-field-nuclear-magnetic-resonance-spectroscopy-to-study-the-surface-structure-and-catalytic-properties-of-poorly-crystalline-al2o3-surfaces\/","title":{"rendered":"The Use of Ultra High-Field Nuclear Magnetic Resonance Spectroscopy to Study the Surface Structure and Catalytic Properties of Poorly Crystalline \u03b3-Al2<\/sub>O3<\/sub> Surfaces"},"content":{"rendered":"

2008 Spring Symposium<\/h3>\n

 
\nCharles H.F. Peden<\/strong>, Ja Hun Kwak, Jian Zhi Hu, Do Heui Kim, and J\u00e1nos Szanyi
\nInsti\u00adtute for Inter\u00adfa\u00adcial Catal\u00ady\u00adsis
\nPacif\u00adic North\u00adwest Nation\u00adal Lab\u00ado\u00adra\u00adto\u00adry
\nRich\u00adland, Wash\u00ading\u00adton 99352, USA<\/em>
\n
\nAbstract<\/strong> \u2014 \u03b3-alu\u00admi\u00adna, one of the metastable \u2018tran\u00adsi\u00adtion\u2019 alu\u00admi\u00adna struc\u00adtur\u00adal poly\u00admorphs, is an impor\u00adtant cat\u00adalyt\u00adic mate\u00adr\u00adi\u00adal both as an active phase and as a sup\u00adport for oth\u00ader cat\u00adalyt\u00adi\u00adcal\u00adly active phas\u00ades. As such, the bulk and sur\u00adface struc\u00adture of \u03b3-alu\u00admi\u00adna, and its for\u00adma\u00adtion and ther\u00admal sta\u00adbil\u00adi\u00adty con\u00adtin\u00adue to be the sub\u00adject of a con\u00adsid\u00ader\u00adable amount of research. How\u00adev\u00ader, due to the low crys\u00adtallini\u00adty and very fine par\u00adti\u00adcle size of \u03b3-alu\u00admi\u00adna, it is very dif\u00adfi\u00adcult to apply well-estab\u00adlished ana\u00adlyt\u00adi\u00adcal tech\u00adniques for deter\u00admin\u00ading its sur\u00adface struc\u00adtures.<\/p>\n

Of par\u00adtic\u00adu\u00adlar impor\u00adtance for under\u00adstand\u00ading the cat\u00adalyt\u00adic prop\u00ader\u00adties of \u03b3-alu\u00admi\u00adna, relat\u00ading its sur\u00adface struc\u00adture to the ori\u00adgin of Lewis acid\u00adi\u00adty has been of con\u00adsid\u00ader\u00adable inter\u00adest and has been stud\u00adied by sol\u00adid state NMR and FTIR spec\u00adtro\u00adscopies, and most recent\u00adly by the\u00ado\u00adret\u00adi\u00adcal cal\u00adcu\u00adla\u00adtions. In this pre\u00adsen\u00adta\u00adtion, we report the first use of very high field (21.1T) NMR to iden\u00adti\u00adfy and quan\u00adti\u00adfy sur\u00adface Al species thought to be respon\u00adsi\u00adble for impart\u00ading Lewis acid\u00adi\u00adty to the \u03b3-Al2<\/sub>O3<\/sub> sur\u00adface. In par\u00adtic\u00adu\u00adlar, a peak in the NMR spec\u00adtrum at ~23 ppm with rel\u00ada\u00adtive\u00adly low inten\u00adsi\u00adty, can be assigned to 5-coor\u00addi\u00adnat\u00aded Al3+<\/sup> ions, and can be clear\u00adly dis\u00adtin\u00adguished from the two oth\u00ader peaks rep\u00adre\u00adsent\u00ading Al3+<\/sup> ions in tetra-, and octa\u00adhe\u00addral coor\u00addi\u00adna\u00adtion sites. Spin-lat\u00adtice 27<\/sup>Al relax\u00adation time mea\u00adsure\u00adments clear\u00adly show that these pen\u00adta-coor\u00addi\u00adnat\u00aded Al3+<\/sup> sites are locat\u00aded on the sur\u00adface of the \u03b3-alu\u00admi\u00adna sup\u00adport. Fur\u00adther\u00admore, we report the first obser\u00adva\u00adtion of pref\u00ader\u00aden\u00adtial anchor\u00ading of an impreg\u00adnat\u00aded cat\u00adalyt\u00adic phase onto these pen\u00adta\u00adco\u00ador\u00addi\u00adnat\u00aded Al3+<\/sup> sites by not\u00ading that BaO and Pt depo\u00adsi\u00adtion onto this \u03b3-alu\u00admi\u00adna sam\u00adple results in the loss of inten\u00adsi\u00adty of the 23 ppm peak lin\u00adear\u00adly pro\u00adpor\u00adtion\u00adal to the amount of cat\u00adalyt\u00adic phase deposit\u00aded. Final\u00adly, our recent results also sug\u00adgest an impor\u00adtant role for these sites in deter\u00admin\u00ading the ther\u00admal sta\u00adbil\u00adi\u00adty of the \u03b3-Al2<\/sub>O3<\/sub> phase dur\u00ading high tem\u00adper\u00ada\u00adture cal\u00adci\u00adna\u00adtion.
\n
\nSpeaker\u2019s Biog\u00adra\u00adphy<\/strong> \u2014 Dr. Peden is Inter\u00adim Direc\u00adtor of the Insti\u00adtute for Inter\u00adfa\u00adcial Catal\u00ady\u00adsis at Pacif\u00adic North\u00adwest Nation\u00adal Lab\u00ado\u00adra\u00adto\u00adry (PNNL). He is also a Lab\u00ado\u00adra\u00adto\u00adry Fel\u00adlow and man\u00adages 8 sci\u00aden\u00adtif\u00adic staff with\u00adin the Chem\u00adi\u00adcal Sci\u00adences Divi\u00adsion at PNNL. Dr. Peden\u2019s main research inter\u00adests are in the sur\u00adface and inter\u00adfa\u00adcial chem\u00adistry of inor\u00adgan\u00adic solids; in par\u00adtic\u00adu\u00adlar, the het\u00adero\u00adge\u00adneous cat\u00adalyt\u00adic chem\u00adistry of met\u00adals and oxides (reac\u00adtion mech\u00ada\u00adnisms, mate\u00adri\u00adals).<\/p>\n","protected":false},"excerpt":{"rendered":"

2008 Spring Sym\u00adpo\u00adsium   Charles H.F. Peden, Ja Hun Kwak, Jian Zhi Hu, Do Heui Kim, and J\u00e1nos Szanyi Insti\u00adtute for Inter\u00adfa\u00adcial Catal\u00ady\u00adsis Pacif\u00adic North\u00adwest Nation\u00adal Lab\u00ado\u00adra\u00adto\u00adry Rich\u00adland, Wash\u00ading\u00adton 99352, USA Abstract \u2014 \u03b3-alu\u00admi\u00ad\u00adna, one of the metastable \u2018tran\u00adsi\u00adtion\u2019 alu\u00admi\u00adna struc\u00adtur\u00adal poly\u00admorphs, is an impor\u00adtant cat\u00adalyt\u00adic mate\u00adr\u00adi\u00adal both as an active phase and as a [\u2026]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[15],"tags":[52],"class_list":["post-654","post","type-post","status-publish","format-standard","hentry","category-abstracts","tag-symposium"],"_links":{"self":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/654","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/comments?post=654"}],"version-history":[{"count":9,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/654\/revisions"}],"predecessor-version":[{"id":2484,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/654\/revisions\/2484"}],"wp:attachment":[{"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/media?parent=654"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/categories?post=654"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/tags?post=654"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}