Title Nanošenje titanatnih nanocijevi na stakleni supstrat Title (english) Deposition of titanate nanotubes on glass substrate Author Matija Galjer Mentor Stanislav Kurajica (mentor)Committee member Stanislav Kurajica (predsjednik povjerenstva)Committee member Juraj Šipušić (član povjerenstva)Committee member Jelena Macan (član povjerenstva)Granter University of Zagreb Defense date and country 2017-06-28, Croatia Scientific / art field, TECHNICAL SCIENCES Abstract Nanotehnologija je područje koje neprestano donosi nova rješenja u raznim znanstvenim, tehnološkim, ekološkim i medicinskim djelatnostima. Nanodimenzionirani materijali posjeduju poneka drugačija svojstva od materijala makro-veličine. Ova specifična svojstva omogućuju korištenje nanočestica u posebne svrhe. Jedan od često korištenih nanodimenzioniranih materijala su titanatne nanocjevčice. One posjeduju neka izvanredna svojstva, kao što su fotokatalitička aktivnost i velika specifična površina. Sposobnost fotokatalize omogućuje korištenje titanatnih nanocjevčica u raznim procesima, primjerice obradi otpadnih voda. U izvedbi ovog procesa često se poseže za heterogenim katalitičkim reakcijama. Jedno od mogućih izvedbi heterogene katalize je korištenje slojeva katalizatora na čvrstom supstratu kako bi se izdvojile i razgradile toksične tvari iz otpadnih voda. Cilj ovog rada je sinteza i karakterizacija titanatnih nanocjevčica, te nanošenje istih na stakleni supstrat u kombinaciji s titanijevim n-butoksidom. Titanatne nanocjevčice pripremljene su hidrotermalnom sintezom te nanesene na stakleni supstrat pomoću oštrice s mogućnosti nanošenja sloja debljine100 µm, bez korištenja isušujućih agensa. Promatran je utjecaj omjera količina titanatnih nanocjevčica i titanijevog n-butoksida na površinsku morfologiju, sastav faza, mehaničku stabilnost nanošenog filma i fotokatalitičku aktivnost titanatnih nanocjevčica. Karakterizacija filmova provedena je pomoću pretražne elektronske mikroskopije, optičke mikroskopije, rendgenske difrakcije, diferencijalne termičke analize (DTA), termogravimetrijske analize (TGA) i diferencijalne termogravimetrijske analize (DTG), metode ljepljive trake, Infracrvene spektroskopije s Fourierovim transformacijama (FTIR), UV-Vis spektroskopije i difuzne reflektancijske spektroskopije (DRS). Fotokatalitička svojstva vrednovana su u procesu degradacije bojila - metilenskog modrila. Tanki filmovi pokazali su kompozitnu morfologiju umreženih titanatnih nanocjevčica zaglađenih gelom. Viši udjeli alkoksida doprinijeli su nastanku defekata i pukotina. Svi uzorci pokazali su fotokatalitičku aktivnost, a kao prihvatljiv kinetički model korišten je model pseudo-prvog reda. Brzina degradacije bojila bila je proporcionalna s prekrivenošću površine filmom i bila je veća za filmove s većim udjelom titanatnih nanocjevčica zbog afiniteta kationskih vrsta ka adsorpciji na površinu nanocjevčica.
Abstract (english) Nanotechnology is a field which is constantly bringing new solutions to science, technology, ecology and medicine. Nanodimensional materials possess various properties which are different in comparison to the macromaterials. Due to these specific properties, usage of nanomaterials in special areas is possible. Titania nanotubes are nanoparticles which are often used. Titania nanotubes possess some of the rare-occurring properties, such as photocatalytic activity and great specific surface area. The possibility of photocatalysis enables for the titania nanotubes to be used in various processes, such as waste water treatment. Waste water treatment includes isolation and removal of the toxic components, or their conversion to non-toxic form. In this process, heterogenic catalysis is often used. One of the possible ways of catalysis performance is usage of solid catalyst on a solid substrate in form of a thin film. The aim of this work was synthesis and characterization of titania nanotubes, and their deposition on the glass substrate in combination with titanium n-butoxide. Titania nanotubes were prepared via hydrothermal method, and deposited by doctor's blade with the optional thickness of the applicated layer of 100 µm, without usage of drying agents. The effect of titania nanotubes to titanium n-butoxide ratio on surface morphology, phase composition, mechanical stability and photocatalytic activity were observed. Characterization was carried out via optical and scanning electron microscope, X-ray diffraction, Fourier-transformed infrared analysis (FTIR), Differential thermal analysis (DTA), Thermogravimetric analysis (TGA), Differential thermogravimetric analysis (DTG), Scotch-tape method and UV-Vis and Diffuse reflectance spectroscopy (DRS). Photocatalytic properties were observed via degradation of methylene blue dye. Thin film showed composite surface morphology of titanate nanotube network which were smoothened out by gel. Higher ratios of alkoxide induced more cracks and defects to the surface. All prepared samples demonstrated efficient photocatalytic activity, pseudo-first order kinetic was found to be an acceptable model for photocatalytic dye degradation. The degradation of dye was proportional to the surface coverage and was increased for the films with greater amount of titania nanotubes due to the affinity of cationic species for adsorption on the surface of nanotubes.
Keywords
titanatne nanocjevčice
tanki filmovi
nanošenje oštricom
fotokataliza
Keywords (english)
titanate nanotubes
thin films
doctor's blade casting
photocatalysis
Language croatian URN:NBN urn:nbn:hr:149:814683 Study programme Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2019-09-27 12:45:55
