TY - JOUR

T1 - Effect of Cu2O Substrate on Photoinduced Hydrophilicity of TiO2 and ZnO Nanocoatings

AU - Maevskaya, Maria V.

AU - Rudakova, Aida V.

AU - Emeline, Alexei V.

AU - Bahnemann, Detlef W.

N1 - Funding Information: Funding: The reported study was funded by RFBR, project number 19-32-90111. Funding Information: Acknowledgments: AVE and MVM are grateful to Russian Foundation for Basic Research (RFBR) for grant N 19-32-90111 to support this research. Experimental studies were performed in laboratory “Photoactive nanocomposite materials” supported by Saint-Petersburg State University (ID: 73032813). We are thankful to the Resource Center (RC) “Nanophotonics”, RC “Centre for Innovative Technologies of Composite Nanomaterials”, RC “X-ray Diffraction Studies”, RC “Centre for Physical Methods of Surface Investigation” and RC “Nanotechnology” of the Research Park at the Saint-Petersburg State University for helpful assistance in the preparation and characterization of the samples.

PY - 2021/6/9

Y1 - 2021/6/9

N2 - The effect of a Cu2 O substrate on the photoinduced alteration of the hydrophilicity of TiO2 and ZnO surfaces was studied. It was demonstrated that the formation of heterostructures Cu2 O/TiO2 and Cu2 O/ZnO strongly changed the direction of the photoinduced alteration of surface hydrophilicity: while both TiO2 and ZnO demonstrate surface transition to superhydrophilic state under UV irradiation and no significant alteration of the surface hydrophilicity under visible light irradiation, the formation of Cu2 O/TiO2 and Cu2 O/ZnO heterostructures resulted in photoinduced decay of the surface hydrophilicity caused by both UV and visible light irradiation. All observed photoinduced changes of the surface hydrophilicity were compared and analyzed in terms of pho-toinduced alteration of the surface free energy and its polar and dispersive components. Alteration of the photoinduced hydrophilic behavior of TiO2 and ZnO surfaces caused by formation of the corresponding heterostructures with Cu2 O are explained within the mechanism of electron transfer and increasing of the electron concentration on the TiO2 and ZnO surfaces.

AB - The effect of a Cu2 O substrate on the photoinduced alteration of the hydrophilicity of TiO2 and ZnO surfaces was studied. It was demonstrated that the formation of heterostructures Cu2 O/TiO2 and Cu2 O/ZnO strongly changed the direction of the photoinduced alteration of surface hydrophilicity: while both TiO2 and ZnO demonstrate surface transition to superhydrophilic state under UV irradiation and no significant alteration of the surface hydrophilicity under visible light irradiation, the formation of Cu2 O/TiO2 and Cu2 O/ZnO heterostructures resulted in photoinduced decay of the surface hydrophilicity caused by both UV and visible light irradiation. All observed photoinduced changes of the surface hydrophilicity were compared and analyzed in terms of pho-toinduced alteration of the surface free energy and its polar and dispersive components. Alteration of the photoinduced hydrophilic behavior of TiO2 and ZnO surfaces caused by formation of the corresponding heterostructures with Cu2 O are explained within the mechanism of electron transfer and increasing of the electron concentration on the TiO2 and ZnO surfaces.

KW - Adsorbed water

KW - Charge transfer

KW - Heterostructures

KW - Photoinduced hydrophilicity

KW - Surface energy

KW - Work function

UR - http://www.scopus.com/inward/record.url?scp=85107455809&partnerID=8YFLogxK

U2 - 10.3390/nano11061526

DO - 10.3390/nano11061526

M3 - Article

AN - SCOPUS:85107455809

VL - 11

JO - Nanomaterials

JF - Nanomaterials

SN - 2079-4991

IS - 6

M1 - 1526

ER -