Primjena rGO/BiVO4 elektrode u fotoelektrokemijskoj razgradnji amoxicilina

undergraduate thesis

• Title (english): Application of rGO/BiVO4 electrode for the photoelectrochemical degradation of amoxicillin
• Author: Ivan Marković
• Mentor: Marijana Kraljić Roković (mentor)
• Committee member: Marijana Kraljić Roković (predsjednik povjerenstva)
• Committee member: Zoran Mandić (član povjerenstva)
• Committee member: Ivana Panžić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2022-09-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Cilj ovog rada bio je ispitati fotoelektrokemijski proces degradacije amoksicilina čija je koncentracija 0,1 mmol dm^-3. Mjerenja su se odvijala na elektrodi sa nanokompozitom koji se sastoji od fotokatalizatora BiVO4 čiji su slojevi naneseni na sloj reduciranog grafenovog oksida (rGO). Mjerenja su provedena za osvijetljene i neosvijetljene elektrode, za što nam je kao izvor služila LED lampa. Za karakterizacije pojedinih elektroda korištena je metoda linearne polarizacije prije i nakon fotoelektrokemijskog procesa, dok se za praćenje samog fotoelektrokemijskog procesa koristila metoda kronoamperometrije. Rezultati su pokazali kako u prisutnosti svjetla dolazi do pojave fotostruja što govori da je došlo do uspješnog stvaranja parova elektron-šupljina. Dobivena mjerenja su također pokazala da radikali nastali u fotoelektrokemijskom procesu oksidiraju rGO. Mjerenja provedena metodom kronoamperometrije ukazuju kako je fotostruja stabilnija pri pH = 6 nego pri pH = 4 iz čega se može zaključiti da se aktivnost elektrode značajnije smanjuje pri nižim pH vrijednostima. Praćenje koncentracije amoksicilina HPLC metodom pokazalo je kako s vremenom dolazi do degradacije amoksicilina. Iako su tijekom ispitivanja metodom linearne polarizacije dobivene veće fotostruje uz deblji sloj BiVO4 tijekom razgradnje farmaceutika nisu zabilježene značajne razlike u brzini razgradnje kod različitih BiVO4 slojeva.

Abstract (english)

The goal of this work was to examine the photoelectrochemical degradation of amoxicillin, whose concentration is 0.1 mmol dm^-3. The measurements were carried out with an electron containing a BiVO4 photocatalyst. The layers of BiVO4 were applied over the reduced graphene oxide (rGO). Measurements were performed for illuminated and non-illuminated electrodes. LED lamp has been used as source of light. The linear polarisation method was used to characterize the electrodes before and after the photoelectrochemical process, while the chronoamperometry method has been used to follow the photoelectrochemical process. The results showed that photocurrent appears in the presence of light, which indicates that there was a successful formation of electron-hole pairs. Additionally, it is evident that radicals formed in the photoelectrochemical process oxidize rGO.The chronoamperometry method shows that the photocurrent is more stable at pH = 6 than at pH = 4 indicating that the activity of electrode decreases with pH decrease. Amoxycilline degradation in photoelectrochemical process was proved by HPLC method. Although linear polarisation shows that higher photocurrents were obtained for thicker layer of BiVO4, photoelectrochemical degradation does not show sigificant differences of pharmaceuticals degradation with different electrodes.

• Keywords: amoksicilin; degradacija farmaceutika; elektrokemijske metode; fotokatalizator; fotoelektrokemijski proces; rGO-BiVO4
• Keywords (english): amoxicillin; degradatiojn of pharmaceutical; electrochemical methods; photocatlyst; photoelectrochemical process; rGO-BiVO4
• Language: croatian
• URN:NBN: urn:nbn:hr:149:918483
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2023-09-01
• Created on: 2023-03-06 13:24:29