Doctoral defence: Dmytro Danilian "Photocatalytic Materials for Water Treatment and Antimicrobial Applications"

On 26 August at 14:00 Dmytro Danilian will defend his doctoral thesis "Photocatalytic Materials for Water Treatment and Antimicrobial Applications" for obtaining the degree of Doctor of Philosophy (in Material Sciences).

Supervisors: 
Vambola Kisand, University of Tartu
Rainer Pärna, University of Tartu
Professor Angela Ivask, University of Tartu

Oponent:
Andrei Kanaev (Laboratoire des Sciences des Procédés et des Matériaux, CNRS, Université Sorbonne Paris, France)

Summary: 
Urbanization have increased levels of harmful pollutants and antibody-resistant microbes in our environment. Now photocatalysis has emerged as an alternative and promising sustainable solution for water cleaning and disinfection. During the reactions photocatalyst itself does not decompose and is an inert nontoxic compound.
This thesis focuses on developing photocatalytic materials based on titanium dioxide (TiO₂) and zinc oxide (ZnO) for water purification and antimicrobial coatings. Firstly, the focus was on the photocatalytic particles used for water purification. For this purpose, magnetically recoverable photocatalysts were synthesized by combining TiO₂–P25 with magnetic copper ferrite. The photocatalyst effectively degraded a commonly used herbicide (2,4-D), and was successfully recovered and reused.
After that, the focus shifted towards the development of photocatalytic antimicrobial coating based on ZnO and Ag-doped ZnO. Nano- or microsized particles of ZnO and ZnO/Ag were embedded to an acrylic matrix and applied onto plywood or stainless steel. These coatings exhibited promising photocatalytic activity and photo-induced antibacterial activity in laboratory conditions. Furthermore, ZnO-based acrylic matrix coatings preserved their photocatalytic and antibacterial efficiency after simulated wear and tear.
Lastly, the commercial photocatalytic window glass based on TiO₂ coatings, BIOCLEAN® and SaniTise™, were investigated. It has been claimed that SaniTise™ has also antimicrobial functionalities. Analyses showed that SaniTise™ demonstrated higher photocatalytic and antibacterial activity than BIOCLEAN®.
Overall, the approach used in this thesis was designed to encompass different aspects of the development and application of photocatalytic materials, enhancing the understanding of material composition and possible use. Continued research in this field can pave the way for eco-friendly photocatalytic systems for water treatment and antimicrobial coatings.