Oxygen Effect on the Structural, Optical and Electrochemical Properties of Radio Frequency Sputtered SnO₂ Thin Films for Photocatalytic Degradation of Methylene Blue

Abstract:

Tin oxide thin films were synthesized on FTO substrates by the Radio Frequency sputtering technique in aO₂/Ar mixture atmosphere. X-ray diffraction patterns revealed the formation of tetragonal structure of SnO₂ films, with a crystallite size that increases from 8.3 to 10.3 nm by increasingthe oxygen percentage from 5% to 15%, then decreases again at 30%oxygen. SEM images reveal homogeneous, smooth, non-porous and crack-free surfaces in all films. EDX spectra confirm the increasing O/Sn ratio for high oxygen percentages. Optical transmittance is observed toincrease with increasing the oxygen percentagewith an energyband gap ranging between 3.78 and 3.91 eV. Mott-Schottky characterization shows higher charge carrier concentration in the film synthesized with 10% O₂. This film exhibits, afterwards, the highest efficiency in terms of degradation of in a UV photoreactor.

• Periodical: Journal of Nano Research (Volume 88)
• Pages: 27-43
• DOI: https://doi.org/10.4028/p-mc1Otd
• Online since: June 2025
• Authors: Mouhcine Ourbaa, Said Elmassi, Hamza Badr, Abdelaziz Tchenka, Jalila Hanyny, Abdelkader El Kissani, Layla El Gaini, Nasser S. Awwad, Abdelfattah Narjis, Lahcen Nkhaili*, Abdelkader Outzourhit
• Keywords: Methylene Blue Degradation, Oxygen Effect, Photocatalysis, RF Sputtering, Tin Oxide

References

[1] P. Vengatesh and T. S. Shyju, "Effect of substrate temperature on reactive RF magnetron sputtered SnO2thin films for photovoltaic applications," Mater. Today Proc., vol. 47, p.1035–1039, 2021.

DOI: 10.1016/j.matpr.2021.06.202

[2] O. Długosz and M. Banach, "ZnO–SnO2–Sn nanocomposite as photocatalyst in ultraviolet and visible light," Appl. Nanosci., vol. 11, no. 5, p.1707–1719, 2021.

DOI: 10.1007/s13204-021-01788-6

[3] G. Elango, S. M. Kumaran, S. S. Kumar, S. Muthuraja, and S. M. Roopan, "Green synthesis of SnO2 nanoparticles and its photocatalytic activity of phenolsulfonphthalein dye," Spectrochim. Acta - Part A Mol. Biomol. Spectrosc., vol. 145, p.176–180, 2015.

DOI: 10.1016/j.saa.2015.03.033

[4] S. Roguai and A. Djelloul, "Elaboration, characterization and applications of SnO2, 2 %Gd-SnO2 and 2 %Gd-9 %F-SnO2 thin films for the photocatalytic degradation of MB by USP method," Inorg. Chem. Commun., vol. 138, no. December 2021, p.109308, 2022.

DOI: 10.1016/j.inoche.2022.109308

[5] T. I. Gandhi, R. R. Babu, K. Ramamurthi, and M. Arivanandhan, Effect of Mn doping on the electrical and optical properties of SnO2 thin films deposited by chemical spray pyrolysis technique, vol. 598. Elsevier B.V., 2016.

DOI: 10.1016/j.tsf.2015.12.008

[6] G. Maharana et al., "Tungsten and fluorine co-doping induced morphology change and textured growth of spray-pyrolyzed SnO2 thin films viable for photocatalytic application," Surfaces and Interfaces, vol. 42, no. PA, p.103413, 2023.

DOI: 10.1016/j.surfin.2023.103413

[7] K. Daideche, H. Lahmar, D. Lerari, and A. Azizi, "Influence of deposition potential on the electrochemical growth and photocatalysis performance of SnO2 nanostructures," Inorg. Chem. Commun., vol. 147, no. August 2022, p.110154, 2023.

DOI: 10.1016/j.inoche.2022.110154

[8] L. Vayssieres, "Growth of arrayed nanorods and nanowires of ZnO from aqueous solutions," Adv. Mater., vol. 15, no. 5, p.464–466, 2003.

DOI: 10.1002/adma.200390108

[9] T. Nobis, E. M. Kaidashev, A. Rahm, M. Lorenz, and M. Grundmann, "Whispering gallery modes in nanosized dielectric resonators with hexagonal cross section," Phys. Rev. Lett., vol. 93, no. 10, p.1–4, 2004.

DOI: 10.1103/PhysRevLett.93.103903

[10] L. Amiri et al., "Spectroscopic study and thermoelectric properties of copper sulfide thin films prepared by the flash evaporation method," J. Alloys Compd., vol. 924, p.166479, 2022.

DOI: 10.1016/j.jallcom.2022.166479

[11] K. Darowicki, S. Krakowiak, and P. Ślepski, "Selection of measurement frequency in Mott-Schottky analysis of passive layer on nickel," Electrochim. Acta, vol. 51, no. 11, p.2204–2208, 2006.

DOI: 10.1016/j.electacta.2005.04.079

[12] D. Ham, S. Oh, and H. C. Kang, "Competing phases in epitaxial SnO2 thin films deposited on sapphire(0001) substrates using radio-frequency powder sputtering," Ceram. Int., vol. 48, no. 19, p.28396–28403, 2022.

DOI: 10.1016/j.ceramint.2022.06.150

[13] S. Elmassi et al., "Effect of RF power on structural, optical and electrical properties of sputtered nickel oxide," Phys. B Condens. Matter, vol. 659, no. March, p.414853, 2023.

DOI: 10.1016/j.physb.2023.414853

[14] M. Ahmadipour, S. N. Ayub, M. F. Ain, and Z. A. Ahmad, "Structural, surface morphology and optical properties of sputter-coated CaCu3Ti4O12 thin film: Influence of RF magnetron sputtering power," Mater. Sci. Semicond. Process., vol. 66, no. March, p.157–161, 2017.

DOI: 10.1016/j.mssp.2017.04.019

[15] H. Zhang, J. Deng, Z. Pan, Z. Bai, L. Kong, and J. Wang, "Structural and optical properties of Nb-doped β-Ga2O3 thin films deposited by RF magnetron sputtering," Vacuum, vol. 146, no. 3, p.93–96, 2017.

DOI: 10.1016/j.vacuum.2017.09.033

[16] D. U. Lee, D. Y. Yun, Y. S. No, J. H. Hwang, C. H. Lee, and T. W. Kim, "Effect of applied voltage on the structural properties of SnO2 nanostuctures grown on indium-tin-oxide coated glass substrates," J. Nanosci. Nanotechnol., vol. 13, no. 11, p.7596–7599, 2013.

DOI: 10.1166/jnn.2013.7883

[17] R. Dangi, B. Basnet, M. Pandey, S. Bhusal, and B. Budhathoki, "Effect of Oxygen Vacancy on the Crystallinity and Optical Band," 2023.

DOI: 10.3390/en16062653

[18] A. Kania, M. M. Szindler, M. Szindler, and Z. Brytan, "Structure and Selected Properties of SnO2 Thin Films," 2024.

DOI: 10.3390/ma17133348

[19] H. Search, C. Journals, A. Contact, M. Iopscience, and I. P. Address, "Structural , electrical and optical properties of transparent conducting SnO 2 films : effect of the oxygen flow rate," vol. 015801, 2012.

DOI: 10.1088/0031-8949/86/01/015801

[20] A. Tchenka et al., "Effect of RF Sputtering Power and Deposition Time on Optical and Electrical Properties of Indium Tin Oxide Thin Film," Adv. Mater. Sci. Eng., vol. 2021, no. Dc, 2021.

DOI: 10.1155/2021/5556305

[21] M. Scimeca, S. Bischetti, H. K. Lamsira, R. Bonfiglio, and E. Bonanno, "Energy Dispersive X-ray ( EDX ) microanalysis : A powerful tool in biomedical research and diagnosis," vol. 62, 2018.

DOI: 10.4081/ejh.2018.2841

[22] A. Tchenka, A. Agdad, and E. Ech-Chamikh, "Determination of the thickness and optical properties by reflectance method," Infrared Phys. Technol., vol. 137, no. December 2023, p.105117, 2024.

DOI: 10.1016/j.infrared.2024.105117

[23] E. F. Rakotonarivo, C. N. Abouloula, A. Narjis, L. Nkhaili, F. Brouillette, and A. Oueriagli, "Optimization of the electrodeposition of the pure and cobalt doped copper oxide for solar cells and other applications," Phys. B Condens. Matter, vol. 609, no. December 2020, p.412783, 2021.

DOI: 10.1016/j.physb.2020.412783

[24] S. Elmassi et al., "Effect of annealing on structural, optical and electrical properties of nickel oxide thin films synthesized by the reactive radio frequency sputtering," Phys. B Condens. Matter, vol. 639, no. April, p.413980, 2022.

DOI: 10.1016/j.physb.2022.413980

[25] M. Suchea, S. Christoulakis, N. Katsarakis, T. Kitsopoulos, and G. Kiriakidis, "Comparative study of zinc oxide and aluminum doped zinc oxide transparent thin films grown by direct current magnetron sputtering," Thin Solid Films, vol. 515, no. 16 SPEC. ISS., p.6562–6566, 2007.

DOI: 10.1016/j.tsf.2006.11.151

[26] F. Cardon and W. P. Gomes, "On the determination of the flat-band potential of a semiconductor in contact with a metal or an electrolyte from the Mott-Schottky plot," J. Phys. D. Appl. Phys., vol. 11, no. 4, 1978.

DOI: 10.1088/0022-3727/11/4/003

[27] A. Ahmed, M. Naseem Siddique, U. Alam, T. Ali, and P. Tripathi, "Improved photocatalytic activity of Sr doped SnO2 nanoparticles: A role of oxygen vacancy," Appl. Surf. Sci., vol. 463, p.976–985, 2019.

DOI: 10.1016/j.apsusc.2018.08.182

[28] Q. Zhao et al., "Oxygen Vacancy Mediation in SnO2 Electron Transport Layers Enables Efficient, Stable, and Scalable Perovskite Solar Cells," J. Am. Chem. Soc., 2024.

DOI: 10.1021/jacs.4c03783

[29] M. Ayadi, O. Benhaoua, M. Sebais, et al. Effect of cerium doping on the structural, optical and photocatalytic properties of SnO2 thin films prepared by spray pyrolysis method. Mater. Res. Express 2019, 6 (7).

DOI: 10.1088/2053-1591/ab10c5

[30] D. Chu et al., "Enhanced photocatalytic properties of SnO2 nanocrystals with decreased size for ppb-level acetaldehyde decomposition," ChemCatChem, vol. 3, no. 2, p.371–377, 2011.

DOI: 10.1002/cctc.201000334