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dc.contributor.advisorKaradaş, Ferdi
dc.contributor.authorAlsaç, Elif Pınar
dc.date.accessioned2017-10-30T12:25:51Z
dc.date.available2017-10-30T12:25:51Z
dc.date.copyright2017-09
dc.date.issued2017-10
dc.date.submitted2017-10-25
dc.identifier.urihttp://hdl.handle.net/11693/33861
dc.descriptionCataloged from PDF version of article.en_US
dc.descriptionThesis (M.S.): Bilkent University, Department of Chemistry, İhsan Doğramacı Bilkent University, 2017.en_US
dc.descriptionIncludes bibliographical references (leaves 89-105).en_US
dc.description.abstractResearch on H2 production has recently been directed to the development of cost-efficient and robust heterogeneous catalysts for splitting of water. While several Prussian blue analogues (PBAs) have been investigated as water oxidation catalysts, the field lacks a comprehensive study that focuses on the design of the ideal PBA for efficient water oxidation. Herein this thesis, a series of PBAs with different cyanide precursors were investigated to study the effect of hexacyanometal group to their electrocatalytic catalytic water oxidation activities. Cyclic voltammetry, chronoamperometry, and chronopotentiometry measurements reveal the close relation between the electron density of electroactive cobalt sites and electrocatalytic activity, which is also confirmed by Infrared and XPS studies. pH dependent cyclic voltammetry studies were also performed to gain insight about the catalytic mechanism and electronic structure of cyanide-based systems, to identify possible intermediates, and assign the rate-determining step of the process. In addition, a N-donor ligand, 1-heptyl 4-(4 pyridyl) pyridinium bromide, was used to prepare a new pentacyanoferrate complex. This complex was used to make a new series of PB analogues to investigate the effect of the change in the morphology to electrocatalytic water oxidation performance. Synthesis, characterization, and electrochemical experiments were performed to investigate electrocatalytic properties of PB analogues. With this synthesis route, the electroactive cobalt sites are increased approximately two-fold. It is observed that amorphous nature has positive impact on the catalytic activity when compared to cobalt hexacyanoferrates. A current density of 1 mA.cm-2 was achieved at an overpotential of 421 mV, which is much lower than those obtained with metal hexacyanometalates. Given the promising catalytic activities of several cobalt-based systems and the robustness of Prussian blue analogues in harsh catalytic processes including water oxidation, a Co-Co Prussian blue analogue was investigated as a Hydrogen evolution catalyst for the first time. Co-Co Prussian Blue modified FTO electrode demonstrated a significant Hydrogen evolution activity with an onset overpotential of 257 mV, a Tafel slope of 80.2 mV.dec-1, and a turnover frequency of 0.090 s-1 at an overpotential of 250 mV. Comparative XPS, Infrared, and XRD studies performed on pristine and post-catalytic electrodes confirm the stability of the catalyst.en_US
dc.description.statementofresponsibilityby Elif Pınar Alsaç.en_US
dc.format.extentxix, 109 leaves : charts (some color), charts, 29 cmen_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectEnergyen_US
dc.subjectWater Oxidationen_US
dc.subjectPrussian Blueen_US
dc.subjectWater Oxidation Catalysten_US
dc.subjectHexacyanideen_US
dc.subjectPentacyanideen_US
dc.subjectCyanideen_US
dc.subjectWater Reduction Catalysten_US
dc.subjectHydrogen Evolution Catalysten_US
dc.subjectElectrocatalysisen_US
dc.titleInvestigation of electrocatalytic performance of prussian blue analogues for water splittingen_US
dc.title.alternativePrusya mavisi türevlerinin suyun ayrışması için elektrokatalitik aktivitelerinin incelenmesien_US
dc.typeThesisen_US
dc.departmentDepartment of Chemistryen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US
dc.identifier.itemidB157043
dc.embargo.release2020-10-15


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