\nDepart\u00adment of Chem\u00adi\u00adcal and Bio\u00admol\u00ade\u00adc\u00adu\u00adlar Engi\u00adneer\u00ading
\nRut\u00adgers, The State Uni\u00adver\u00adsi\u00adty of New Jer\u00adsey <\/em>
\n
![\"Fuat](\"http:\/\/catalysisclubphilly.org\/awe9a91v\/uploads\/2015\/03\/FuatCelik.png\")
<\/a>\nAbstract<\/strong>
\nIn sup\u00adport\u00aded met\u00adal cat\u00ada\u00adlysts, the trade\u00adoff between activ\u00adi\u00adty and selec\u00adtiv\u00adi\u00adty presents an impor\u00adtant chal\u00adlenge for cat\u00ada\u00adlyst design. By allow\u00ading two dis\u00adsim\u00adi\u00adlar met\u00adals, we can attempt to tune the selec\u00adtiv\u00adi\u00adty of the cat\u00ada\u00adlyst by enhanc\u00ading bond-for\u00adma\u00adtion and des\u00adorp\u00adtion rates through the addi\u00adtion of a less-reac\u00adtive ele\u00adment, while main\u00adtain high bond dis\u00adso\u00adci\u00ada\u00adtion activ\u00adi\u00adty from the more active met\u00adal. The result\u00ading cat\u00ada\u00adlyst prop\u00ader\u00adties depend strong\u00adly on the cat\u00ada\u00adlyst com\u00adpo\u00adsi\u00adtion and ratio of the two met\u00adals (elec\u00adtron\u00adic effect), but may also depend on the local struc\u00adture of sur\u00adface ensem\u00adbles of the alloy com\u00adpo\u00adnents (geo\u00admet\u00adric effect). In this talk we will explore two exam\u00adples of bina\u00adry alloys where sur\u00adface com\u00adpo\u00adsi\u00adtion and geom\u00ade\u00adtry play an impor\u00adtant role in deter\u00admin\u00ading the selec\u00adtiv\u00adi\u00adty of the cat\u00ada\u00adlyst through den\u00adsi\u00adty func\u00adtion\u00adal the\u00ado\u00adry (DFT).<\/p>\n
In the first exam\u00adple, we have exam\u00adined the effect of plat\u00adinum tin alloy struc\u00adture and com\u00adpo\u00adsi\u00adtion on the kinet\u00adics and ther\u00admo\u00addy\u00adnam\u00adics of dehy\u00addro\u00adgena\u00adtion and coke for\u00adma\u00adtion path\u00adways dur\u00ading light alka\u00adne dehy\u00addro\u00adgena\u00adtion. Light alka\u00adne dehy\u00addro\u00adgena\u00adtion to olefins can add sig\u00adnif\u00adi\u00adcant val\u00adue to hydro\u00adcar\u00adbon process\u00ades that gen\u00ader\u00adate ethane and propane by con\u00advert\u00ading low val\u00adue com\u00admod\u00adi\u00adty fuels to high-val\u00adue chem\u00adi\u00adcal and poly\u00admer pre\u00adcur\u00adsors. Sup\u00adport\u00aded Pt cat\u00ada\u00adlysts are known to be active but show sig\u00adnif\u00adi\u00adcant coke for\u00adma\u00adtion and deac\u00adti\u00adva\u00adtion, which can be alle\u00advi\u00adat\u00aded by alloy\u00ading with Sn and oth\u00ader main group ele\u00adments. We aim to under\u00adstand how the struc\u00adture and com\u00adpo\u00adsi\u00adtion of these alloys affect their abil\u00adi\u00adty to sup\u00adpress coke for\u00adma\u00adtion. We inves\u00adti\u00adgate the poten\u00adtial ener\u00adgy sur\u00adfaces from ethane along the desired path\u00adway to ethene, and along the unde\u00adsired path\u00adways towards sur\u00adface carbon\/coke. The effect of Pt\/Sn ratio and sur\u00adface geom\u00ade\u00adtry is inves\u00adti\u00adgat\u00aded. As com\u00adpared to pure Pt, bond scis\u00adsion is more dif\u00adfi\u00adcult on the alloys and des\u00adorp\u00adtion is more facile, and both effects are enhanced as three-fold hol\u00adlow sites con\u00adsist\u00ading of only Pt atoms are elim\u00adi\u00adnat\u00aded.<\/p>\n
In the sec\u00adond exam\u00adple, we eval\u00adu\u00adate Au\/Ni near-sur\u00adface alloys as poten\u00adtial oxy\u00adgen reduc\u00adtion cat\u00ada\u00adlysts for the direct syn\u00adthe\u00adsis of hydro\u00adgen per\u00adox\u00adide from O2 and H2, there\u00adby avoid\u00ading the cur\u00adrent anthraquinone process. While Au may have high\u00ader O-H bond for\u00adma\u00adtion activ\u00adi\u00adty, it is a poor O2-dis\u00adso\u00adci\u00ada\u00adtion cat\u00ada\u00adlyst, and like\u00adwise Ni is very effec\u00adtive at O2-dis\u00adso\u00adci\u00ada\u00adtion but not oxy\u00adgen hydro\u00adgena\u00adtion. Alloy\u00ading Au with Ni(111) low\u00aders H2 dis\u00adso\u00adci\u00ada\u00adtion bar\u00adri\u00ader while keep\u00ading the O2 dis\u00adso\u00adci\u00ada\u00adtion bar\u00adri\u00ader large rel\u00ada\u00adtive to O2 hydro\u00adgena\u00adtion. Des\u00adorp\u00adtion of H2O2 is sim\u00adi\u00adlar\u00adly com\u00adpet\u00adi\u00adtive with H2O2 dis\u00adso\u00adci\u00ada\u00adtion on alloy sur\u00adfaces. How\u00adev\u00ader, the selec\u00adtiv\u00adi\u00adty for the OOH rad\u00adi\u00adcal remains a chal\u00adlenge, with bar\u00adri\u00ader\u00adless O-O bond dis\u00adso\u00adci\u00ada\u00adtion and large (1.3 eV) hydro\u00adgena\u00adtion bar\u00adri\u00aders. We fur\u00adther inves\u00adti\u00adgate how the Au\/Ni sur\u00adface may rearrange itself to regen\u00ader\u00adate three-fold hol\u00adlows of Ni atoms in the pres\u00adence of strong\u00adly adsorb\u00ading sur\u00adface species.<\/p>\n","protected":false},"excerpt":{"rendered":"
Meet\u00ading Pro\u00adgram \u2014 March 2015 Fuat E Celik Depart\u00adment of Chem\u00adi\u00adcal and Bio\u00admol\u00ade\u00adc\u00adu\u00adlar Engi\u00adneer\u00ading Rut\u00adgers, The State Uni\u00adver\u00adsi\u00adty of New Jer\u00adsey Abstract In sup\u00adport\u00aded met\u00adal cat\u00ada\u00adlysts, the trade\u00adoff between activ\u00adi\u00adty and selec\u00adtiv\u00adi\u00adty presents an impor\u00adtant chal\u00adlenge for cat\u00ada\u00adlyst design. By allow\u00ading two dis\u00adsim\u00adi\u00adlar met\u00adals, we can attempt to tune the selec\u00adtiv\u00adi\u00adty of the cat\u00ada\u00adlyst by [\u2026]<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[15],"tags":[],"class_list":["post-4216","post","type-post","status-publish","format-standard","hentry","category-abstracts"],"_links":{"self":[{"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4216","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/comments?post=4216"}],"version-history":[{"count":1,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4216\/revisions"}],"predecessor-version":[{"id":4218,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/posts\/4216\/revisions\/4218"}],"wp:attachment":[{"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/media?parent=4216"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/categories?post=4216"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/catalysisclubphilly.org\/awe9a91v\/wp-json\/wp\/v2\/tags?post=4216"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}