Utilizing Spectroscopy and Optical Microscopy to Characterize Titanium Dioxide Thin Films

Keywords: Nano-crystalline titanium dioxide, Particles/Pin holes, Surface band gap, Transmittance, STS measurements


This paper presents the surface electronic structure and morphological characteristics of the nano-crystalline titanium dioxide (nc TiO2) films derived from the two different sol-gels. Using Scanning tunneling microscopy/spectroscopy (STM/S), it was found that the particles of nc-TiO2 produced from batch A have a surface band gap of ~3.3 eV while the particles of nc-TiO2 produced from batch B have a surface band gap of ~2.6 eV. On other hand, the small particles have aggregated together to form larger particles ranging from ~120 nm to 150 nm in size and distributed randomly over the surface of the batch A nc-TiO2 films. For batch B nc-TiO2films, the small particles have formed larger particles but with their size ranging from 200 nm to 225 nm. That is ascribed to differences between sol-gels used to prepare nc-TiO2 films. As a result of that, the electric power of batch A nc-TiO2/P3HT solar cells is enhanced by more than 8 times in comparison with batch B solar cells.


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C. Leyens, and M. Peters, Titanium and Titanium Alloys: Fundamental and Application, (Wiley, VCH, 2003).

M. Kralova, M. Vesely, and P. Dzik, “Physical and chemical properties of titanium dioxide printed layers”, Catal. 161(1), 97 (2011). https://doi.org/10.1016/j.cattod.2010.11.019

H. Al-Dmour, RH. Alzard, H. Alblooshi, K. Alhosani, S. AlMadhoob, and N. Saleh, “Enhanced Energy Conversion of Z907-Based Solar Cells by Cucurbituril Macrocycles”, Font.Chem. 561, 1 (2019). https://doi.org/10.3389/fchem.2019.00561

Y. Liang, and H. Ding, “Mineral-TiO2 composites:Preparation and application in papermaking, paints and plastics”, J. Alloys Compd. 844, 156139 (2020). https://doi.org/10.1016/j.jallcom.2020.156139

A. Fujishima, and K. Honda, “Electrochemical Photolysis of Water at a Semiconductor Electrode”, Nature, 238, 37 (1972). https://doi.org/10.1038/238037a0

K. Gopinath, N. Madhav, A. Krishnan, R. Malolan, and G. Rangarajan, “Present applications of titanium dioxide for the photocatalytic removal of pollutants from water: A review”, J. Environ. Manage. 270, 110906 (2020) https://doi.org/10.1016/j.jenvman.2020.110906

B. O’Regan, and M. Grätzel, Nature, 353, 373 (1991). https://doi.org/10.1038/353737a0

I. Hao, J, Yan, S. Guan, L, Cheng, Q. Zhao, Z. Zhu, Y. Wang, Y. Lu, and J. Liu, “Oxygen vacancies in TiO2/SnO coatings prepared by ball milling followed by calcination and their influence on the photocatalytic activity”, Appl. Surf. Sci. 466, 490 (2019). https://doi.org/10.1016/j.apsusc.2018.10.071

H. Al Dmour, D.M. Taylor, and J.A. Cambridge, “Effect of nanocrystalline-TiO2 morphology on the performance of polymer heterojunction solar cells”, J. Phys. D, 40(17), 5034 (2007). https://doi.org/10.1088/0022-3727/40/17/004

F. Petronella, A. Pagliarulo, A. Truppi, M. Lettieri, M. Masieri, A. Calia, and R. Comparelli, “TiO2 Nanocrystal Based Coatings for the Protection of Architectural Stone: The Effect of Solvents in the Spray-Coating Application for a Self-Cleaning Surfaces”, Coating. 8(10), 356 (2018). https://doi.org/10.3390/coatings8100356

A. Thomas, and K. Syres, “Adsorption of organic molecules on rutile TiO2 and anatase TiO2 single crystal surfaces”, Chem. Soc. Rev. 41, 4207 (2012). https://doi.org/10.1039/c2cs35057b

NT-MDT Spectrum Instruments, Proezd 4922, 4/3 Zelenograd, Moscow 124460, Russia, http://www.ntmdt.com

C. Dette, O. Pérez, C. Kley, P. Punke, E. Patrick, P. Jacobson, F. Giustino, et al, “TiO2 Anatase with a Bandgap in the Visible Region”, Nano Lett. 14(11), 6533 (2014). https://doi.org/10.1021/nl503131s

A.A. Abd El-Moula, M. Raaif, and F.M. El-Hossary, “Optical Properties of Nanocrystalline/Amorphous TiO2 Thin Film Deposited by rf Plasma Magnetron Sputtering”, Acta Phys. Pol. A, 137, 1068 (2020). https://doi.org/10.12693/APhysPolA.137.1068

H. Al Dmour, and D.M. Taylor, “Revisiting the origin of open circuit voltage in nanocrystalline-TiO 2/polymer heterojunction solar cells”, Appl. Phys. Lett. 94, 223309 (2009). https://doi.org/10.1063/1.3153122

M. Wu, J. Wu, C. Yen, H. Lo, F. Lin, and F. Su, “Correlation between nanoscale surface potential and power conversion efficiency of P3HT/TiO2 nanorod bulk heterojunction photovoltaic devices”, Nanoscale, 2(28), 1448 (2010). https://doi.org/10.1039/b9nr00385a

H. Al Dmour, “A Capacitance response of solar cells based on amorphous Titanium dioxide (A-TiO2) semiconducting heterojunctions”, AIMS Mater. Sci. 8(2), 261 (2021). https://doi.org/10.3934/matersci.2021017

W.J.E. Beek, M.M. Wienke, M. Kemerink, X. Yang, and R.A.J. Janssen, “Hybrid Zinc Oxide Conjugated Polymer Bulk Heterojunction Solar Cells”, J. Phys. Chem. B, 109, 9505 (2005). https://doi.org/10.1021/jp050745x

How to Cite
Al Dmour, H. (2022). Utilizing Spectroscopy and Optical Microscopy to Characterize Titanium Dioxide Thin Films. East European Journal of Physics, (4), 171-175. https://doi.org/10.26565/2312-4334-2022-4-17