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dc.contributor.advisorÖzensoy, Emrah
dc.contributor.authorErcan, Kerem Emre
dc.date.accessioned2016-04-27T12:56:10Z
dc.date.available2016-04-27T12:56:10Z
dc.date.copyright2015-09
dc.date.issued2015-09
dc.date.submitted15-09-2015
dc.identifier.urihttp://hdl.handle.net/11693/29003
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (leaves 74-83).en_US
dc.descriptionThesis (M.S.): Bilkent University, Department of Chemistry, İhsan Doğramacı Bilkent University, 2015.en_US
dc.description.abstractThe main purpose of this study is to identify the nature of hybrid perovskites in the form of LaCoxMn1-xO3 (x=0.0-1.0) for catalytic De-NOx applications. Characteristic structure, thermal stability and NOx/SOx adsorption/release properties of perovskites were studied by XRD, BET, XPS, in-situ FTIR, ex-situ FTIR, TEM, BET, TPD and TPR. LaCo0.8Mn0.2 and LaCo0.7Mn0.3O3 were found to yield the highest NOx storage Capacity (NSC) among other investigated perovskites due to their optimized B-site composition. NOx and SOx adsorption experiments pointed out that B-site substitution did not have a significant alteration on adsorption geometries of corresponding adsorbates. NOx uptakes of the investigated perovskites were observed to be enhanced via H2 reduction as verified by IR results. Furthermore, N2 (28 a.m.u) release monitored by QMS during NOx TPD revealed direct N-O bond activation and complete reduction of NOx species under certain conditions. SOx adsorption and reduction experiments suggested that SOx reduction via H2 is more effective for Mn-enrich perovskites, since Co-enriched materials formed irreversible sulfate species. It was observed that adsorbed NOx species can be readily replaced by SOx species in the co-presence of NOx and SOx. It was also demonstrated that the oxygen-defect density and the surface oxygen concentration of hybrid perovskites can be modified by fine-tuning the substitution at the B-site. Based on ex-situ FTIR results, it was established that Co-O linkages could be gradually replaced with Mn-O linkages by increasing the Mn loading in the perovskite composition. Furthermore, specific surface areas (SSA) of hybrid perovskites were found to be enhanced by increasing the Mn loading. Current results suggest that hybrid perovskites are promising novel catalytic architectures for De-NOx applications due to their high NSC and versatile chemical structure which can be fine-tuned to enhance SOx tolerance, redox properties and thermal stability.en_US
dc.description.statementofresponsibilityby Kerem Emre Ercanen_US
dc.format.extentxvi, 83 leaves : charts.en_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectPerovskiteen_US
dc.subjectNOxen_US
dc.subjectSOxen_US
dc.subjectLaMnO3en_US
dc.subjectLaCoO3en_US
dc.subjectLaCoxMn1-xO3en_US
dc.titleNovel hybrid perovskite catalysts for DE-NOx applicationsen_US
dc.title.alternativeDe-nox uygulamaları için yeni nesil hibrit perovskitleren_US
dc.typeThesisen_US
dc.departmentDepartment of Chemistryen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US
dc.identifier.itemidB151301
dc.embargo.release2017-09-14


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