Applied research in photocatalysis, solid state gas sensors, self-cleaning and antimicrobial surfaces

The group has a long-time interest in research on photocatalytic surfaces, with application in air cleaning and water cleaning. Employing either sun light, real or simulated, or artificial light sources, typically LEDs, removal of hazardous compounds are studies. We perform research on new synthesis methods and concepts for utilizing photocatalytic materials (e.g. pure, mixed, and doped transition metal oxides, heterojunction and hybrid materials involving 2D materials). The photocatalysts are either made as thin films, nanoporous coatings, photonic band gap structures, and multi-layer films with synergetic properties for UV absorption (photocatalysis) and NIR absorption (heat). A multifunctional photocatalytic/thermochromic coated window with spectrally enhanced indoor air cleaning properties is shown in Fig. 6

Figure 6: Photocatalytic removal of air pollutants present in the indoor air environment by means of a multifunctional photocatalytic-thermochromic coated window

Photocatalysts such as TiO2 are also superhydrophilic under bandgap illumination, and can be used as self-cleaning surfaces to transport away pollutants from a surface. We study advanced wetting properties of hierarchical structured binary and ternary oxides, and combinations of them. Acid-base modified surface modifications, such as SO4-TiO2, yields acid surfaces with oleophobic, and sustained photocatalytic properties (Fig 7a). Yttrium oxyhydride films exhibit light-induced hydrophobicity (Fig. 7b). Combinations of controlled wettability and catalytic activity with nanopattering and chromogenic nanocoatings can be used to create optical Lotus coatings for e.g. omnidirectional anti-reflective and self-modulating cover glass for solar cells.

Figure 7: (a) A textured SO4-TiO2 film is oleophobic, repelling grease […]. (b) An Yttrium oxyhydride (YHO) film becomes hydrophobic upon illumination.

[32] J. Montero, J. Thyr, I. T. Dedova, O. Acik, L. Österlund, CuOx-ZnO NR, Synthesis and Characterization of CuOx/ZnO Bicatalysts for Enhanced Photodegradation Of Orange II Dye. RSC Advances 1, 10224-10234 (2021).
[33] Jiří Henych, Štěpán Stehlík, Karel Mazanec, Jakub Tolasz, Jan Čermák, Bohuslav Rezek, Andreas Mattsson, and Lars Österlund, Reactive adsorption and photodegradation of Soman And Dimethyl Methylphosphonate on TiO2/Nanodiamond Composites, Applied Catalysis B: Environmental 259 (2019) 118097.
[34] Ji, Y., Mattsson, A., Niklasson, G. A., Granqvist, C. G., & Österlund, L. (2019). Synergistic TiO2/VO2 window coating with thermochromism, enhanced luminous transmittance, and photocatalytic activity. Joule, 3(10), 2457-2471.
[35] Lars Österlund, Andreas Mattsson, Martin Brischetto, Joel Johansson Byberg, Bozhidar I. Stefanov, Yu-Xia Ji & Gunnar A. Niklasson, Spectrally selective heat absorptive bilayer photocatalyst with enhanced reactivity: TiO2/TiAlN, Top. Catal., Volume 61, Issue 15–17 (2018) 1607–1614.
[36] Jiri Henych, Vaclav Stengl, Andreas Mattsson, Lars Österlund, In situ FTIR spectroscopy study of the photo-degradation of acetaldehyde and azo dye photobleaching on bismuth-modified TiO2, Photochem. Photobiol. 91 (2015) 48-58,
[36] Tarek S. Jamil, Montaser Y. Ghaly, Nady A. Fathy, Tarek A. Abd el-halim, Lars Österlund, Enhancement of TiO2 behavior on photocatalytic oxidation of MO dye using TiO2/AC under visible irradiation and sunlight radiation, Sep. Purif. Technol. 98, 270–279 (2012).
[37] Z. Topalian, G. A. Niklasson, and L. Österlund, Spectroscopic Study of the Photofixation of SO2 on Anatase TiO2 Thin Films and Their Oleophobic Properties, ACS Appl. Mater. Interfaces, 4, 672−679 (2012).
[38] Z. Topalian, G. Niklasson, C.-G Granqvist and L. Österlund, Photo-fixation of SO2 in nanocrystalline TiO2 films prepared by reactive DC magnetron sputtering, Thin Solid Films 518, 1341–1344 (2009).
[39] E.M. Baba, J. Montero (corr.), E. Strugovshchikov, E.Ö. Zayim, E.Z. Karazhanov, Light-induced breathing in photochromic yttrium oxy-hydrides, Phys. Rev. Mater. 4 (2019) 25201.

Last modified: 2022-03-17