News

Group members

Thesis defended

Mateusz Trochowski  has got his PhD degree. Congratulations!

Diversity of the photosensitization mechanisms of surface-functionalized oxide semiconductors.

The doctoral thesis is focused on verification of four hypotheses related to the photosensitization mechanisms of titanium(IV) oxide and zinc oxide. The first hypothesis concerned the possibility of protection of photosensitizers bound to the TiO2 surface by covering them with a thin layer of titanium(IV) oxide to improve the photostability. The strategy worked only for a minority of the tested samples. The second hypothesis was the higher stability of dihydroxy derivatives of anthraquinone comparised to catechol adsorbed at TiO2. Long-term photocatalytic tests have shown that all obtained materials are more photostable than the reference catechol/TiO2 system and some of them are also more active. The third problem concerned investigation how insignificant modifications of photocatalysts can significantly change their photocatalytic activity. A significant effect on photocatalytic activity, of the studied materials, in particular upon visible light irradiation, was observed, although changes in the phase composition, spectroscopic properties and morphology of the samples tested were negligible. The fourth hypothesis concerned determining of the mechanisms of localized surface plasmon resonance interaction with ZnO modified with Au nanoparticles. The analysis of emission spectra has shown that photosensitization of ZnO occurs most probably via the transfer of “hot” electrons.

 

Group members

Paulina got married

 

Today Paulina has changed her marital state. She is now very excited and needs some time to relax to reach the ground state.
Congratulations!

General

Scientific cooperation

The cooperation with Prof. Janusz Nowotny and Prof. Tad Bak reaches new level – Marcin Kobielusz spends two month as a visiting reasercher in School of Computing, Engineering and Mathematics, Western Sydney University.

Award

We play SHENG with Wuhan!

The Team of Photocatalysis has been granted with almost 1.4 million zloty for the joint Polish-Chinese research project entitled “Photocatalytic reduction of carbon dioxide based on p-type semiconductors”. The project is supported by the National Science Centre, Poland (NCN) and the National Natural Science Foundation of China (NSFC). Together with the group of Prof. Jiaguo Yu from Wuhan University of Technology we will focus on the development of p-type semiconducting photocatalysts, used alone or in combination with n-type semiconductors, for a more efficient solar fuels production encompassing one- and multi-electron CO2 reduction. Briefly, the artificial photosynthesis is our goal!


Conference

8th Czech – Polish Catalytic Symposium

Our results were presented at the 8th Czech – Polish Catalytic Symposium, held in Ostrava, Czech Republic, on February 15th 2019. We have presented 5 lectures. Symposium as always was packed with many interesting presentations but we also had time for discussions.

General

Thesis defended

Marcin Surówka  has got his PhD degree. Congratulation!

Photocatalytic Degradation of Herbicides at Titanium(IV) Oxide Modified with Metal Salts and Oxides

The doctoral thesis was focused on environmental problems related to contamination of water with herbicides: 2,4-D and 2,4,5-T. One of the most promising methods for water purification is heterogeneous photocatalysis. In this work a wide library of photocatalysts based on titanium(IV) oxide was synthetized. They were modified with different amounts (0.01-0.50%mol metal:Ti) of salts and oxides of following metals: Fe, Co, Ga, Bi, W, Mo, V and Ni. The materials were calcined at three chosen temperatures and characterised structurally and spectroscopically with XRD, UV-vis/DRS and photocurrent measurements. Their photocatalytic activity was investigated in the processes of terephthalic acid oxidation and herbicides and azure B degradation. Based on these studies the most favourable synthesis parameters were proposed: small modifier content and middle chosen calcination temperature, which result in both anatase and rutile presence in the final material. The most significant conclusion stated in this work is confirmation of indirect influence of modifiers on the photocatalytic activity of the materials. The role of modifiers is mostly observed during the photocatalyst synthesis – they influence the anatase to rutile ratio, being the main factor determining the overall photocatalytic activity of TiO2. Therefore, such modifiers are regarded as TiO2-synthesis-steering factors.