Е-Публикации
Технически университет - София

Abstract: All Rights Reserved.In the study, the photocatalytic activity of TiO2 films that are created by dip-coating from a sol that contained titanium (IV) isopropoxide, monoethanolamine, and 2-methoxyethanol is demonstrated. Through photo-fixation of Ag (I) ions with varied concentration (10-2 - 10-4 M) in the water phase under UV illumination, the films are subsequently surface-modified with Ag co-catalyst layers. Scanning Electron Microscopy (SEM), X-Ray Photoelectron Spectroscopy (XPS), Ultraviolet-Visible (UV) Spectroscopy, and Electron Paramagnetic Resonance (EPR) techniques are used to physically characterize the samples. Results reveal that the modification of the cocatalyst had no impact on the thickness and porosity of the films. In addition, the study show that the modified TiO2 films had increased photocatalytic activity. All the characterization methods used have shown the formation of surface - bound Ag (I) species and metallic silver nanoclusters. By measuring the Methylene Blue (MB) dye degradation under UV light illumination, as - prepared and Ag -modified TiO2 films are evaluated for their photocatalytic activity, and the impact of the silver precursor concentration during photo-fixation is investigated. The highest catalytic activity is seen for films that have been modified at a concentration of Ag (I) of 10-2M. Ordered from highest to lowest, the MB photodegradation rate constants are TiO2 < TiO2 /Ag, 10-4 < TiO2 /Ag, 10-3 < TiO2 / Ag, 10-2.

References

1. 1. S. Sadikin, J. Ridwan, M. Umar, A. Raub, J. Yunas, A. Hamzah, D. Dahlan, M. Rahman, A. Umar, Photocatalytic activity and stability properties of porous TiO2 film as photocatalyst for methylene blue and methylene orange degradation, Int. J. Electrochem. Sci., 18, 9, 2023, 100246.
2. 2. G. Canbaz, N. Çakmak, A. Eroğlu, Ü. Açıkel, Removal of Acid Orange 74 from wastewater with TiO2 nanoparticle, Int. Adv. Res. Eng. J., 03, 2019, 75-80.
3. 3. D. Kim, Sh. Han, S. Kwak, Synthesis and photocatalytic activity of mesoporous TiO2 with the surface area, crystallite size, and pore size, J. Colloid Interface Sci., 316, 1, 2007, 85-91.
4. 4. J. Jeong, Ch. Lee, Structural properties and photocatalytic activity of amorphous-crystalline TiO2 thin films, Thin Solid Films, 788, 2024, 140178.
5. 5. M. Nasr, C. Eid, R. Habchi, P. Miele, M. Bechelany, Recent progress on titanium dioxide nanomaterials for photocatalytic applications, Chem. Sus. Chem., 11, 2018, 3023-3047.
6. 6. T. Pathak, R. Kroon, V. Craciun, M. Popa, M. Chifiriuc, H. Swart, Influence of Ag, Au and Pd noble metals doping on structural, optical and antimicrobial properties of zinc oxide and titanium dioxide nanomaterials, Heliyon, 5, 2019, e01333.
7. 7. S. Tauster, S. Fung, R. Garten, Strong metal-support interactions. group 8 noble metals supported on TiO2, J. Am. Chem. Soc., 100, 1978, 170-175.
8. 8. M. Khairy, E. Kamar, M. Mousa, Photocatalytic activity of nano-sized Ag and Au metal-doped TiO2 embedded in rGO under visible light irradiation, Mater. Sci. Eng. B, 286, 2022, 116023.
9. 9. M. Kanoun, F. Ahmed, Ch. Awada, Ch. Jonin, P. Brevet, Band gap engineering of Au doping and Au-N codoping into anatase TiO2 for enhancing the visible light photocatalytic performance, Inter. J. Hydrogen Energy, 51, C, 2024, 907-913.
10. 10. J. Belošević-Čavor, V. Koteski, V. Ivanovski, D. Toprek, A. Umićević, Tailoring the photocatalytic properties of anatase TiO2 by B-TM (TM = Pt, Ta, V) co-doping, Physica B: Condensed Matter, 670, 2023, 415358.
11. 11. S. Lee, I. Yoo, R. Singh, Y. Lee, S. Kalanur, H. Seo, Enhanced photocatalytic properties of band structure engineered Pd/TiO2 via sequential doping, Appl. Surf. Sci., 570, 2021, 151255.
12. 12. D. Shirley, High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold, Phys. Rev. B, 5, 1972, 4709-4714.
13. 13. J. Scofield, Hartree, Slater subshell photoionization cross-sections at 1254 and 1487 eV, J. Electron. Spectrosc. Relat. Phenom., 8, 1976, 129-137.
14. 14. J. Coronado, A. Maira, J. Conesa, K. Yeung, V. Augugliaro, J. Soria, EPR Study of the Surface Characteristics of Nanostructured TiO2 under UV Irradiation, Langmuir, 17, 2001, 5368-5374.
15. 15. J.W. Rodriguez-Acosta, M.Á. Mueses, F. Machuca-Martínez, Mixing Rules Formulation for a Kinetic Model of the Langmuir-Hinshelwood Semipredictive Type Applied to the Heterogeneous Photocatalytic Degradation of Multicomponent Mixtures, Int. J. Photoen., 9, 2014, 817538.
16. 16. R.S. André, C.A. Zamperini, E.G. Mima, Antimicrobial activity of TiO2:Ag nanocrystalline heterostructures: Experimental and theoretical insights, Chem. Phys., 459, 2015, 87-95.

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