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Synthesis and characterization of structurally ordered interactive electrocatalytic composites based on metal oxides and platinum

dc.contributor.advisorPanić, Vladimir
dc.contributor.otherGojković, Snežana
dc.contributor.otherGrgur, Branimir N.
dc.contributor.otherJovanović, Vladislava M.
dc.creatorKošević, Milica
dc.date.accessioned2022-01-12T13:11:12Z
dc.date.available2022-01-12T13:11:12Z
dc.date.issued2021
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=8155
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:23800/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=39963913
dc.identifier.urihttps://nardus.mpn.gov.rs/handle/123456789/18356
dc.identifier.urihttps://cer.ihtm.bg.ac.rs/handle/123456789/4931
dc.description.abstractIspitivana su svojstva titan(IV)-oksida i njegove karakteristike kao mogućeg interaktivnog i stabilnog nosača za RuO2 i Pt kao elektrokatalizatora u reakcijama od značaja za industrijsku elektrohemiju i alternativne izvore energije. Analizirano je i razmatrano kako u slučaju kompozita RuO2/TiO2 i Pt/TiO2, sintetizovanih na takav način da se dobijaju njihove uređene strukture, TiO2 služi kao stabilišuće i interaktivno jezgro, a RuO2, odnosno Pt, kao elektrokatalitički aktivna komponenta.Kompoziti RuO2/TiO2 i Pt/TiO2 su sintetizovani različitim hidrotermalnim metodama, koje uključuju temperaturno kontrolisan prelaz aerosolova i hidrosolova u čvrstu fazu. Kod kompozita RuO2/TiO2 se ispitivao uticaj temperature u pirolitičkom reaktoru na morfologiju dobijenog kompozita RuO2/TiO2 i stabilnost anoda koje su dobijene nanošenjem ovako dobijenog kompozita na Ti podlogu.Svojstva dobijenih kompozita analizirana su u zavisnosti od toga da li su sve faze sintetizovane u jednom koraku (in-situ) ili je faza nosača TiO2 sintetizovana prethodno (ex-situ). Strukturno-morfološka svojstva dobijenih materijala ispitivana su mikroskopskim tehnikama (SEM, TEM), analizom interakcije materijala sa elektromagnetnim zračenjem (FTIR, XRD, DLS, ramanska spektroskopija) i termogravimetrijskom analizom. Elektrohemijske karakteristike ispitivane su analizom nefaradejskog odziva i elektrokatalitičke aktivnosti i stabilnosti u reakcijama izdvajanja hlora i kiseonika (RuO2/TiO2), odnosno redukcije kiseonika i izdvajanja vodonika (Pt/TiO2).Nađeno je da se svi kompoziti dobijaju u obliku sferoidnih čestica/aglomerata, bez obzira na postupak dobijanja. Uređenost i ravnomernost strukture zavise od primenjenog postupka pripreme, kao i temperature prelaza u čvrstu fazu.Elektrohemijskim karakteristikama RuO2/TiO2 pogoduje niža temperatura pirolitičke sinteze, iako je utvrđeno da u tom slučaju izostaje potpuna konverzija prekursora rutenijuma u odgovarajući oksid. RuO2/TiO2 dobijen na nižoj temperaturi se pokazao stabilnijim, sa boljim kapacitivnim karakteristikama, usled karakteristične raspodele komponenti i faza kroz zapreminu matičnih sferoidnih strukturnih oblika kompozita. Za nominalno isti sastav RuO2/TiO2 dobijen na nižoj i višoj temperaturi, razmatrano je kako elektrohemijske karakteristike zavise od mikroskopske raspodele oksidnih komponenti kroz sferične aglomerate. Takođe, ovi nalazi diskutovani su uzimajući u obzir i kristalno stanje TiO2 u formi anatasa, koji pretežno čini jezgro ovih aglomerata.Kod kompozita Pt/TiO2 se ispitivao uticaj temperature sinteze i tipa sinteze na morfološka svojstva dobijenog kompozita i njegovu elektrokatalitičku aktivnost. Svi dobijeni kompoziti su bili sfernog oblika, nezavisno od primenjenih uslova sinteze. U ex-situ pristupu USP sintezi se dobijaju pravilna sferna jezgra čija je površina prekrivena ljuskom u vidu nanometarskih platinskih čestica, dok se in-situ pristupom dobija smeša većih šupljih sfera i manjih čvrstih sfera. Najbolja elektrokatalitička svojstva pokazuje kompozit sintetizovan ex-situ pristupom na umerenoj temperaturi.sr
dc.description.abstractProperties and characteristics of titanium(IV) oxide, as posible interactive and stable support for RuO2 and Pt electrocatalysts, are studied. RuO2 and Pt are important electrocatalytic materials, often used in industrial electrochemistry and alternative power sources. It was found that in Pt/TiO2 and RuO2/TiO2 composites synthesized in a way which enables highly ordered structures TiO2 acts like a stabilising and interactive core, while Pt and RuO2 are electrocatalyticaly active components encapsulating the core. As supporting component in both Pt/TiO2 and RuO2/TiO2 composites, TiO2 synthesis and its characterisation is performed separately.RuO2/TiO2 and Pt/TiO2 composites are synthesiezed using varouis hydrothermal approches consisting of temperature-controled conversion of aerosols and hydrosols to the solid phase. In the case of RuO2/TiO2 composite, influence of synthesis temperature on the morphology of the obtained composites was studied. Influence of the synthesis temperature on the stability of activated Ti anodes coated by obtained composites was examined as well.Dependance of the properties of the obtained composites on the applied synthesis approach was investigated. In-situ approach as one-step synthesis is applied along with the ex-situ approach, which implies that at least supporting component, TiO2, has been prepared prior to the composite synthesis. Strucutral and morphological properties of the obtained materials were tested using SEM, TEM, FTIR, XRD, DLS, Raman and TGA techniques. Electrochemical characterization involved the analysis of non-Faradaic response and electrocatalytic activity and stability in chlorine and oxygen evolution reactions (RuO2/TiO2), as well as oxygen reduction and hydrogen evolution reactions (Pt/TiO2).It was found that all synthesized composites had spherical shape, independently of the synthesis method. Structure arrangement and uniformity depend on the applied approach, as well as on the synthesis temperature. Although conversion of ruthenium precursor to coresponding oxide was not complete at lower synthesis temperature, this temperature is beneficial for electrochemical characteristics of the RuO2/TiO2 composite. Namely, RuO2/TiO2 composite synthesiezed at lower temperature had better stability and capacitive characteristics.Influence of the microscopic distribution of the oxide components throughout the spherical agglomerates on the electrochemical characteristics of the RuO2/TiO2 composites synthesized at two different temperatures, with same nominal composition, was investigated. In addition, the disscusion takes into account the influence of the anatase TiO2 that cores are primary consisted of.Influence of the synthesis temperature and method on the morphological properties and electrocatalytic activity of the obtained Pt/TiO2 composites were examined. All of the prepared composites were of spherical shape, independently of the applied conditions. Regular spherical cores covered by a shell of nanometric platinum particles were obtained by ex-situ approach, whereas in-situ aproach resulted in mixture of huge hollow speheres and smaller all-solid spheres. The most promising electocatalytical properties were obtained by ex-situ USP method at moderate temperatures.en
dc.languagesr
dc.publisherУниверзитет у Београду, Технолошко-металуршки факултетsr
dc.relationinfo:eu-repo/grantAgreement/MESTD/Basic Research (BR or ON)/172060/RS//
dc.rightsopenAccessen
dc.rights.urihttps://creativecommons.org/licenses/by-nc-nd/4.0/
dc.sourceУниверзитет у Београдуsr
dc.subjectPrevlaka RuO2/TiO2sr
dc.subjectRuO2/TiO2 coatingen
dc.subjectultrazvučna sprej pirolizasr
dc.subjectizdvajanje vodonikasr
dc.subjectizdvajanje hlora i kiseonikasr
dc.subjectnanouređena struktura jezgro/ljuskasr
dc.subjectPt na nosačusr
dc.subjectTiO2 kao nosač elektrokatalizatorasr
dc.subjectultrasonic spray pyrolysisen
dc.subjecthydrogen evolution reactionen
dc.subjectchlorine and oxygen evolution reactionsen
dc.subjectsupported Pt nanoparticlesen
dc.subjectTiO2 as an electrocatalyst supporten
dc.titleSinteza i karakterizacija strukturno uređenih interaktivnih elektrokatalitičkih kompozita zasnovanih na oksidima metala i platinisr
dc.title.alternativeSynthesis and characterization of structurally ordered interactive electrocatalytic composites based on metal oxides and platinumen
dc.typedoctoralThesisen
dc.rights.licenseBY-NC-ND
dc.identifier.rcubhttps://hdl.handle.net/21.15107/rcub_nardus_18356
dc.identifier.fulltexthttp://cer.ihtm.bg.ac.rs/bitstream/id/21346/Doktorat_28806.pdf
dc.identifier.fulltexthttp://cer.ihtm.bg.ac.rs/bitstream/id/21347/IzvestajKomisije28806.pdf
dc.type.versionpublishedVersion


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