TY - JOUR

T1 - Self-cleaning properties of zirconium dioxide thin films

AU - Rudakova, A.V.

AU - Emeline, A.V.

AU - Bulanin, K.M.

AU - Chistyakova, L.V.

AU - Maevskaya, M.V.

AU - Bahnemann, D.W.

N1 - Funding information: The present study was performed within the Project “Establishment of the Laboratory “Photoactive Nanocomposite Materials” No. 14.Z50.31.0016 supported by a Mega-grant of the Government of the Russian Federation . A.V. Rudakova and K.M. Bulanin thank to the RFBR No. 18-03-0085518 grant which supported the studies of photocatalytic and antibacterial activities. Authors are also grateful to the RC “Nanophotonics”, RC “Nanotechnology”, RC “X-ray Diffraction Studies”, RC “Optical and Laser Materials Research”, RC “Centre for culturing collections of microorganisms”, and RC “Centre for Physical Methods of Surface Investigation” of the Research Park at the Saint-Petersburg State University for helpful assistance in conducting synthesis and characterization of the samples.

PY - 2018/12/1

Y1 - 2018/12/1

N2 - Here we focused on the fundamental study of self-cleaning properties of zirconium dioxide films, including photoinduced alteration of surface hydrophilicity, photocatalytic and photoinduced bactericidal activities. The accent was made on the factors influencing the photoinduced hydrophilic conversion such as surface acidity and spectral composition of light for the surface photoexcitation. The studies on photoinduced hydrophilic conversion of the ZrO 2 thin film were carried out using the contact angle measurements and XPS method. The experimental data demonstrate the very different hydrophilic behavior of the hydrated surface depending on the spectral region of photoexcitation corresponding to intrinsic or extrinsic ZrO 2 absorption. This is explained by the difference in the concentration of photoelectrons and photoholes which participate in the photo-induced surface processes. It is suggested that hole-trapping species such as surface hydroxyl groups and adsorbed water molecules play a crucial role in the photoinduced superhydrophilic transition. The effect of the electron-acceptor and electron-donor gas atmospheres on the aging of the surface superhydrophilicity is found to be in agreement with this conclusion. The photochemical activity of ZrO 2 coatings was tested by photodegradation of stearic acid. The antibacterial properties are investigated against Escherichia coli. The ZrO 2 thin films reveal self-cleaning properties and can be successfully used as biomedical or construction material.

AB - Here we focused on the fundamental study of self-cleaning properties of zirconium dioxide films, including photoinduced alteration of surface hydrophilicity, photocatalytic and photoinduced bactericidal activities. The accent was made on the factors influencing the photoinduced hydrophilic conversion such as surface acidity and spectral composition of light for the surface photoexcitation. The studies on photoinduced hydrophilic conversion of the ZrO 2 thin film were carried out using the contact angle measurements and XPS method. The experimental data demonstrate the very different hydrophilic behavior of the hydrated surface depending on the spectral region of photoexcitation corresponding to intrinsic or extrinsic ZrO 2 absorption. This is explained by the difference in the concentration of photoelectrons and photoholes which participate in the photo-induced surface processes. It is suggested that hole-trapping species such as surface hydroxyl groups and adsorbed water molecules play a crucial role in the photoinduced superhydrophilic transition. The effect of the electron-acceptor and electron-donor gas atmospheres on the aging of the surface superhydrophilicity is found to be in agreement with this conclusion. The photochemical activity of ZrO 2 coatings was tested by photodegradation of stearic acid. The antibacterial properties are investigated against Escherichia coli. The ZrO 2 thin films reveal self-cleaning properties and can be successfully used as biomedical or construction material.

KW - Antibacterial activity

KW - Coating

KW - Photocatalytic activity

KW - Photoexcitation

KW - Photoinduced hydrophilicity

KW - Self-cleaning

KW - Surface acidity

KW - Thin film

KW - Zirconium oxide

UR - http://www.scopus.com/inward/record.url?scp=85053319961&partnerID=8YFLogxK

U2 - 10.1016/j.jphotochem.2018.08.037

DO - 10.1016/j.jphotochem.2018.08.037

M3 - Article

VL - 367

SP - 397

EP - 405

JO - Journal of Photochemistry and Photobiology A: Chemistry

JF - Journal of Photochemistry and Photobiology A: Chemistry

SN - 1010-6030

ER -