Napredni poluvodički materijali za fotokatalitičku primjenu

undergraduate thesis

• Title (english): Advanced semiconducting materials for photocatalysis
• Author: Ina Polić
• Mentor: Jozefina Katić (mentor)
• Committee member: Jozefina Katić (predsjednik povjerenstva)
• Committee member: Marijana Kraljić Roković (član povjerenstva)
• Committee member: Stjepan Milardović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2019-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Fotokataliza jest reakcija koja se odvija kada poluvodički materijal, odnosno fotokatalizator apsorbira kvant svjetlosti i u pobuđenom stanju fotokatalizator sudjeluje u kemijskim pretvorbama. Fotokataliza je promjena u kinetici kemijske reakcije potaknuta djelovanjem svjetla u kontaktu s fotokatalizatorom. Uslijed adsorpcije kvanta svjetlosti veće energije od energije zabranjene zone poluvodičkog materijala dolazi do nastajanja elektron-šupljina parova (elektroni iz valentne vrpce pobuđuju se u vodljivu vrpcu pri čemu u valentnoj vrpci nastaju šupljine). Nastali pobuđeni elektroni i šupljine mogu reagirati s elektron-donorima i elektron-akceptorima adsorbiranim na površinu poluvodičkog fotokatalitičkog materijala. U današnje se vrijeme poluvodički fotokatalizatori, uglavnom oksidi i sulfidi prijelaznih metala, zbog svoje niske cijene, prirodne dostupnosti i dostatne aktivacije energijom Sunčevog zračenja, ubrajaju u napredne materijale široke primjene. Koriste se u procesima konverzije energije (fotoliza vode i dobivanje vodika kao goriva) i zaštite okoliša (fotokatalitička razgradnja opasnih tvari u vodama).

Abstract (english)

Photocatalysis is reaction occurring due to the absorbance of light energy quantum by semiconducting material, the so called photocatalyst and in excited state photocatalyst actively participates in the chemical reactions. Photocatalysis is change in chemical reaction kinetics induced by absorbed light in contact with photocatalyst material. Upon absorption of light energy higher than the band gap energy of the semiconducting material, the formation of electron-hole pairs takes place (electrons are excited from the valence band to the conduction band resulting in formation of holes in the valence band). Formed excited electrons and holes can react with electron-donors and electron-acceptors adsorbed on the surface of the semiconductor photocatalyst material. Nowadays, semiconductor photocatalysts, mainly oxides and sulfides of transition metals, due to their low cost, nature abundance and sufficient solar energy activation efficiency, are considered as advanced materials of wide application. They are used in the energy conversion processes (water photolysis and obtaining of hydrogen as fuel) and in the environmental protection applications (photocatalytic decomposition of hazardous organic substances in water).

• Keywords: fotokatalizator; poluvodički materijali; valentna i vodljiva vrpca; energija zabranjene zone; obrada otpadnih voda
• Keywords (english): photocatalysis; semiconducting materials; valence and conduction band; band gap; wastewater treatment
• Language: croatian
• URN:NBN: urn:nbn:hr:149:042081
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Applied organic chemistry; 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: Access restricted to students and staff of home institution
• Created on: 2023-05-26 14:08:24