Razvoj i primjena imobiliziranih kompozitnih fotokatalizatora dobivenih sol-gel postupkom

doctoral thesis

• Title (english): Development and application of immobilized composite photocatalysts obtained by sol-gel process
• Author: Igor Jajčinović
• Mentor: Ivan Brnardić (mentor)
• Mentor: Ivana Grčić (komentor)
• Committee member: Anita Štrkalj (predsjednik povjerenstva)
• Committee member: Tamara Holjevac Grgurić (član povjerenstva)
• Committee member: Vedrana Špada (član povjerenstva)
• Granter: University of Zagreb; Faculty of Metallurgy; Sisak
• Defense date and country: 2025-01-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy

Abstract

U ovom radu korišten je fotokatalizator titan(IV) oksid (TiO2) zbog svoje dostupnosti, kemijske i biološke inertnosti, ali i dobrih fotokatalitičkih svojstava. Da bi se olakšala njegova primjena u usporedbi sa suspendiranim oblikom provedena je njegova imobilizacija na mrežu od staklenih vlakana sol-gel postupkom. Istraživano je mogu li se u procesu sušenja primijeniti i mikrovalovi zbog same brzine sušenja i pripreme fotokatalizatora te je utvrđen negativan utjecaj. Daljnje istraživanje bilo je usmjereno prema dopiranju TiO2 višeslojnim ugljičnim nanocijevima (MWCNT) i grafen oksidom (GO) s ciljem poboljšanja fotokatlitičke aktivnosti TiO2 pri Sunčevom zračenju. Dopiranje je provedeno s različitim udjelima MWCNT u odnosu na masu TiO2: 1,5, 5, 10, 25, 50 i 100 mas. %. Najbolju fotokatalitičku aktivnost pokazao je fotokatalizator dopiran s 10 mas.% MWCNT u usporedbi s pripravljenim TiO2 fotokatalizatorom. Na temelju istraživanja fotokatalizatora pripremljenog s MWCNT pripremljeni su i fotokatalizatori dopirani s GO i to u udjelima od 5, 10 i 25 mas. %. Rezultati su pokazali da GO negativno utječe na fotokatalizu. Fotokatalitička aktivnost pripremljenih fotokatalizatora je praćena razgradnjom modalne otopine salicilne kiseline UV-Vis spektrofotometrom pod simuliranim Sunčevim zračenjem. Salicilna kiselina je korištena kao primjer mikroonečišćenja koje se uvelike pojavljuje u okolišu jer ima široku primjenu u lijekovima i kozmetičkim proizvodima. Nadalje, istražena je postojanost pripravljenih fotokatalizatora te su rezultati starenja na zraku i u vodi pokazali da je moguća višekratna uporaba pripremljenih fotokatalizatora bez značajnog opadanja njegove aktivnosti.

Abstract (english)

It was investigated whether microwaves could also be used for the drying process due to the speed of drying and the preparation of the photocatalyst, and a negative impact was determined. Further research was focused on the doping of titanium(IV) oxide (TiO2) with multi wall carbon nanotubes (MWCNT) and graphene oxide (GO) with the aim of improving the photocatalytic activity of TiO2 under solar radiation. The doping was carried out with different proportions of MWCNT in relation to the mass of the TiO2: 1.5, 5, 10, 25, 50 and 100 wt. %. The photocatalyst doped with 10 wt. % MWCNT showed the best photocatalytic activity compared to the photocatalyst prepared with TiO2. Based on the study of the photocatalyst prepared with MWCNT, photocatalysts doped with GO were also prepared in proportions of 5, 10 and 25 wt. %. The results showed that GO has a negative effect on the photocatalysis. The photocatalytic activity of the prepared photocatalysts was monitored by decomposing the salicylic acid modal solution with a UV-Vis spectrophotometer under simulated solar radiation. Salicylic acid was used as an example of a micropollutant that is widely present in the environment as it is often used in pharmaceuticals and cosmetic products. Furthermore, the stability of the prepared photocatalysts was investigated, and the results of aging in air and in water showed that repeated use of the prepared photocatalysts is possible without a significant decrease in its activity.

• Keywords: Titan(IV) oksid; fotokataliza; mikroonečišćenja; ugljične nanocijevi; grafen oksid
• Keywords (english): Titanium(IV) oxide; photocatalysis; micropollutants; carbon nanotubes; graphene oxide
• Language: croatian
• URN:NBN: urn:nbn:hr:115:812571
• Promotion: 2025
• Study programme: Title: Doctoral study mechanical engineering, naval architecture, aeronautical engineering, metallurgical engineering; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje tehničkih znanosti (doktor/doktorica znanosti, područje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-03-15 13:23:58