Sinteza metalnih nanočestica iz površinski aktivnih tvari s prijelaznim metalima

master's thesis

• Title (english): Synthesis of metal nanoparticles from metallosurfactants
• Author: Nina Koščević
• Mentor: Jelena Macan (mentor)
• Committee member: Jelena Macan (predsjednik povjerenstva)
• Committee member: Domagoj Vrsaljko (član povjerenstva)
• Committee member: Vesna Tomašić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Cilj ovog rada bio je istražiti sintezu metalnih nanočestica Co, Ni i Cu kemijskom redukcijom pomoću dimernih PAT koje u svojoj strukturi sadrže metale, (12–2–12)[MBr4], M = Co, Ni, Cu, u dva različita medija, u vodi i emulziji heksan/voda. Jedno od važnih svojstava PAT koje u svojoj strukturi sadrže metale je sposobnost asocijacije u različite molekulske asocijate kao što su npr. micele, koje mogu poslužiti i kao izvor metalnih iona i kao predložak za sintezu metalnih nanočestica. Sinteza metalnih nanočestica je već duže vrijeme u centru pažnje znanstvenika jer zahvaljujući svojim specifičnim fizikalno-kemijskim svojstvima pružaju široku mogućnost primjene u različitim granama industrije, medicine i farmacije. Jedna od najjednostavnijih metoda sinteze metalnih nanočestica je kemijska redukcija, no ona često zahtijeva upotrebu toksičnih kemikalija. Korištenjem PAT kao izvora nanočestica te istovremeno kao stabilizatora, smanjuje se potreba za dodatnim kemikalijama.
Za određivanje veličine i morfologije sintetiziranih metalnih nanočestica korištene su mikroskopske tehnike, pretražna elektronska mikroskopija (SEM) i transmisijska elektronska mikroskopija (TEM), a za utvrđivanje prisutnih kemijskih elemenata, energijski razlučujući spektrometar (EDS). Za određivanje veličine i ζ potencijala dobivenih nanočestica korišteno je dinamičko raspršenje svjetlosti (DLS) i elektroforetsko raspršenje svjetlosti (ELS). Utvrđeno je da sinteza iz vode, iako ekološki prihvatljivija, lošiji sintetski put u odnosu na emulzije heksan/voda. U svim pokušajima sinteze izolirane su nanočestice metalnih oksida što je vidljivo iz snimljenih EDS spektara. Pomoću TEM i DLS analiza pokazano je da su pojedinačne nanočestice jako male i odgovaraju otprilike veličini micela dimernih PAT, ali su sklone agregiranju usprkos relativno velikim ζ potencijalima.

Abstract (english)

The aim of this study was to investigate the synthesis of Co, Ni, and Cu nanoparticles from dimeric surfactants (12–2–12)[MBr4], M = Co, Ni, Cu using chemical reduction method, in two different media: water and a hexane/water emulsion. An important property of dimeric surfactants containing metals is their ability to form metallomicelles, which can act both as a source of metal ions and as a template for the synthesis of metallic nanoparticles.
The synthesis of metallic nanoparticles has attracted considerable attention because of their distinctive physicochemical properties, which enable a broad spectrum of applications across diverse industries, particularly in medicine and pharmaceuticals. Chemical reduction is one of the simplest methods for synthesizing metallic nanoparticles, although it often requires toxic chemicals. By using dimeric surfactants as both a source of nanoparticles and as stabilizers, the need for additional chemicals is reduced. Microscopic techniques, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to determine the size and morphology of the synthesized metallic nanoparticles, while energy dispersive spectroscopy (EDS) was employed to identify the chemical elements present. Dynamic light scattering (DLS) and electrophoretic light scattering (ELS) were used to measure particle size and zeta potential. The findings indicate that while synthesis in water is more environmentally friendly, it is a less effective synthetic route compared to the hexane/water emulsion. In all synthesis attempts, metallic oxide nanoparticles were isolated, as shown by the recorded EDS spectra. TEM and DLS analyses revealed that individual nanoparticles were very small, approximately the size of the dimeric surfactant micelles, but they tended to aggregate despite relatively high zeta potentials.

• Keywords: dinamičko raspršenje svjetlosti; metali; nanočestice; površinski aktivne tvari; pretražna elektronska mikroskopija; transmisijska elektronska mikroskopija
• Keywords (english): dynamic light scattering; metals; nanoparticles; metallosurfactants; scanning electron microscopy; transmission electron microscopy
• Language: croatian
• URN:NBN: urn:nbn:hr:149:696117
• Study programme: Title: Chemical Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-09-19
• Created on: 2024-11-11 11:01:50