Vpliv modifikacij na lastnosti mezoporoznega silicijevega dioksida

Pancar, Kaja (author), Cerc Korošec, Romana (mentor), Sever Škapin, Andrijana (comentor)

V laboratoriju sintetiziran silicijev dioksid predstavlja obetaven material za številne aplikacije: kot dostavni sistem zdravilnih učinkovin, senzorski sistem za zaznavanje analitov (preko adsorpcije) in kot katalitski sistem. Z uporabo površinsko aktivnih snovi ali polimerov je mogoče pripraviti delce SiO2 z dobro definirano porozno strukturo. Takšen material ima premer kanalov por med 2 nm in 50 nm in se po IUPAC imenuje mezoporozni material. Z nadaljnjimi modifikacijami lahko na površino mezoporoznega SiO2 kovalentno vežemo organske funkcionalne skupine, s čimer mu spremenimo lastnosti ter funkcionaliziramo površino materiala za določen namen. Proces pripenjanja novih funkcionalnih skupin na površino materiala imenujemo funkcionalizacija. Modifikacija SiO2 ni enoznačna in enostavna, saj nanjo vpliva veliko parametrov, ki imajo močan vpliv na lastnosti končnega produkta. Nedvoumno karakterizacijo otežuje tudi nehomogenost površine sintetiziranega materiala. Namen mojega magistrskega dela je bila sinteza mezoporoznih delcev SiO2 in nadaljnje sistematične modifikacije njihove površine z različnimi organosilanskimi reagenti. S tem postopkom na površino SiO2 kovalentno vežemo aminske, tiolne, etilne oz. fenilne skupine. Funkcionaliziran mezoporozni SiO2 smo okarakterizirali s sorpcijo dušika, infrardečo spektroskopijo, FE-SEM ter TG/DTG meritvami. Sposobnost adsorpcije molekul barvila na površino SiO2 smo ovrednotili z merjenjem količine adsorbiranega barvila, za kar smo uporabili UV-Vis spektrometrijo. Rezultate karakterizacije modificiranih SiO2 materialov smo med seboj primerjali in jih povezali s parametri modifikacij.

• Language: Slovenian
• Keywords: silicijev dioksid, mezoporoznost, funkcionalizacija površine SiO2, organosilan
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2020
• PID: 20.500.12556/RUL-117407
• COBISS.SI-ID: 22870531
• Publication date in RUL: 09.07.2020

PANCAR, Kaja, 2020, Vpliv modifikacij na lastnosti mezoporoznega silicijevega dioksida [online]. Master’s thesis. [Accessed 17 May 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=117407

Secondary language

• Language: English
• Title: Effect of modification on the properties of mesoporous silicon dioxide

Abstract

In the laboratory scale, synthesized silica has become a promising material for many applications, such as the delivery system for drugs, sensor system for the detection of analytes (via adsorption) and as the catalytic system. With the help of surfactants or polymers it is possible to prepare SiO2 particles with a well-defined porous structure. Pore tunnels have diameter between 2 nm and 50 nm. According to IUPAC nomenclature they are called mesoporous materials. With further modifications, organic functional groups can be covalently bound to the surface of mesoporous SiO2, thereby changing the SiO2 properties and functionalizing the surface of the material for a specific purpose. The process of attaching new functional groups to the surface of a material is called functionalization. The modification of SiO2 is not straightforward and simple, as it is influenced by many parameters. Unambigous characterization is also hindered by inhomogeneity of the surface of the synthesized material. The purpose of my master's thesis was synthesis of mesoporous SiO2 particles and further systematic modification of it’s surface with different organosilane reagents. In this way, amine, thiol, ethyl or phenyl groups were covalently bound to the SiO2 surface. Functionalized mesoporous SiO2 was characterized by nitrogen sorption, infrared spectroscopy, FE-SEM and TG/DTG measurements. The ability of adsorption of dye molecules to the SiO2 surface was evaluated by measuring the amount of dye adsorbed with the use of UV-Vis spectroscopy. Obtained properties of the modified SiO2 materials were compared and correlated with modification parameters. The aim of the research in the master's thesis was to evaluate the influence of modification parameters and the choice of organosilane reagent on the properties of the final product.

• Keywords: silicon dioxide, mesoporosity, functionalization of the SiO2 surface, organosilane