Influence of Oblique Angle Deposition on the Structural, Optical, and Photocatalytic Performance of TiO₂ Thin Films

Document Type : Original Article

Authors

1 Department of Physics, Faculty of Science, Arak University, Arak, Iran

2 Department of Nanoscience & Nanotechnology, Arak University, Arak, Iran

10.22075/ppam.2026.39966.1189

Abstract

In the present study, TiO₂ thin films were deposited on glass substrates using thermal evaporation technique at oblique angles of 40°, 60°, 70°, and 80° to study the influences of deposition angles on the structural, optical, and photocatalytic properties of the deposited films. FESEM and AFM studies showed increasing deposition angle results in a porous and rough surface morphology. This is attributed to shadowing effects and limited adatom diffusion. The optical transmittance and absorption spectra were recorded using a UV–Vis spectrophotometer, indicating that films deposited at higher oblique angles exhibited enhanced light transmission and modified absorption behavior. The photocatalytic activity of the TiO₂ thin films was evaluated through methylene orange degradation under UV irradiation. The degradation efficiency was followed in time steps of 30, 60, 90, and 120 min. The results showed that the sample deposited at 60° exhibits the maximum photocatalytic activity. This is regarded as an enhancement due to its optimized surface roughness and increased surface area, improving photon absorption and charge carrier separation. 

Keywords

Main Subjects


© 2026 The Author(s). Progress in Physics of Applied Materials published by Semnan University Press. This is an open access article under the CC-BY 4.0 license. (https://creativecommons.org/licenses/by/4.0/)

[1]Tulli, F., Morales, J.M., Salas, E.E., Moran Vieyra, F.E. and Borsarelli, C.D., 2021. Photocatalytic efficiency tuning by the surface roughness of TiO2 coatings on glass prepared by the doctor blade method. Journal of Photochemistry and Photobiology, 97, pp.22-31.
[2]Kirk, C.H., Wang, P., Chong, C.Y.D., Zhao, Q., Sun, J. and Wang, J., 2024. TiO2 photocatalytic ceramic membranes for water and wastewater treatment: Technical readiness and pathway ahead. Journal of Materials Science, 183, pp.152-164.
[3]Salmaniannezhad, H., Salmaniannezhad, H., Zarei Moghadam, R., Khani, M., Ardani, M. and Shokri, B., 2023. Design and fabrication of multi-layers antireflection coating consisting of MgF2 and SiO2. Progress in Physics and Applied Materials, 3, pp.141-146.
[4]Yousefzadeh, S., Rostam Jadidoleslam, N. and Moharrami, K., 2026. Hydrothermally Synthesized TiO2 Nanostructures on Ti foil for Visible Light Assisted Photocatalytic Degradation of Tetracycline. Progress in Physics and Applied Materials, 6, pp.15-25.
[5]O'Byrne, M., Kerzabi, B., Abbarchi, M., Lifschitz, A., Zamora, T., Malgras, V., Gourdin, A., Modaresialam, M., Grosso, D. and Putero, M., 2024. Investigation of the anatase-to-rutile transition for TiO2 sol-gel coatings with refractive index up to 2.7. Thin Solid Films, 790, p.140193.
[6]Adedokun, O., Obaseki, O.S., Yam, F.K., Ooi, M.D.J., Adedokun, O.M. and Jubu, P.R., 2024. Influence of growth temperature on structural, optical, morphological and photoelectrochemical characteristics of vertically aligned hydrothermally synthesized TiO2 nanorods. Physica B: Condensed Matter, 688, p.416155.
[7]Lee, S.H., Na, K.H., Kim, J.Y., Yoon, H.S., Han, H. and Choi, W.Y., 2024. Fabrication and characterization of electrospun Cu-doped TiO2 nanofibers and enhancement of photocatalytic performance depending on Cu content and electron beam irradiation. Polymers, 16, p.694.
[8]Wang, Y.H., Rahman, K.H., Wu, C.C. and Chen, K.C., 2020. A review on the pathways of the improved structural characteristics and photocatalytic performance of titanium dioxide (TiO2) thin films fabricated by the magnetron-sputtering technique. Catalysts, 10, p.598.
[9]Lan, N.T.K., Duoc, N.T., Duy, N.N., Van Chung, C., Du, B.D. and Hien, N.Q., 2020. Synthesis of Ag nano/TiO2 by electron beam irradiation for photo‐degradation of rhodamine B compound in water. Vietnam Journal of Chemistry, 58, pp.398-403.
[10]Villamayor, A., Pomone, T., Perero, S., Ferraris, M., Barrio, V.L., G-Berasategui, E. and Kelly, P., 2023. Development of photocatalytic nanostructured TiO2 and NiO/TiO2 coatings by DC magnetron sputtering for photocatalytic applications. Ceramics International, 49, pp.19309-19317.
[11]Hawkeye, M.M., Taschuk, M.T. and Brett, M.J., 2014. Introduction: Glancing angle deposition technology. In: Glancing Angle Deposition of Thin Films.
[12]Quang, D.D., Nguyen, T.N., Nguyen, D.T., Hai, T.N.D., Vu, T.H., Le, T.T., Vu, T.M. and Le, V.V., 2025. Fabrication and characterization of pulsed electron beam deposited TiO2 thin films with glancing angle deposition techniques for biosensing application. Vietnam Journal of Science and Technology, 63, pp.285-296.
[13]Yasuda, Y., Kitahara, N. and Hoshi, Y., 2013. Glancing Angle Sputter Deposition of Titanium Dioxide Films for Photocatalytic Applications. ECS Transactions, 50, pp.25-35.
[14]Pandey, A.K., Tiwari, A.K. and Paliwal, H., 2022. Enhancement of mechanical, thermal and optical properties of TiO2 thin films using glancing angle deposition technique. Optical Materials, 134, p.113054.
 
[15]Bensouici, F., Bououdina, M., Dakhel, A.A., Tala-Ighil, R., Tounane, M., Iratni, A., Souier, T., Liu, S. and Cai, W., 2017. Optical, structural and photocatalysis properties of Cu-doped TiO2 thin films. Applied Surface Science, 395, pp.110-116.
[16]Zarei Moghadam, R., Omrany, A.H., Taherkhani, M. and Shokrian, F., 2021. Fabrication of multi-layer antireflection coating consisting of ZnS and MgF2. Progress in Physics and Applied Materials, 1, pp.7-13.
[17]Naas, L.A., Bouaouina, B., Bensouici, F., Mokeddem, K. and Abaidia, S.E., 2024. Effect of TiN thin films deposited by oblique angle sputter deposition on sol-gel coated TiO2 layers for photocatalytic applications. Thin Solid Films, 793, p.140275.
[18]Kang, M., Kim, S.W. and Park, H.Y., 2018. Optical properties of TiO2 thin films with crystal structure. Journal of Physics and Chemistry of Solids, 123, pp.266-270.