<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Photocatalytic degradation of organic pollutants from wastewater using titanium dioxide is recognized as an efficient process. To be feasible, this process needs to be solar- or visible light -activated, but, due to its wide band gap energy, titanium dioxide can only be activated by ultraviolet radiation. In this paper, thin films of titanium dioxide were deposited by Spray Pyrolysis Deposition using organo-metallic (titanium-iso-propoxide) and inorganic (titanium chloride) precursors, as a first step in optimizing the deposition process of titanium dioxide - carbon composite thin films, active in the visible spectral range. The thin films were characterized to outline the differences when using these two precursor solutions, when deposited on Fluorine doped Tin Oxide-glass, regular glass and microscopic glass, in terms of crystallinity (by using X-ray diffraction), elemental composition (using Energy Dispersive X-ray spectrometry), surface morphology (Scanning Electronic Microscopy and Atomic Force Microscopy). The photocatalytic activity of the titanium dioxide thin films was investigated based on the removal efficiencies of methylene blue from a synthetically prepared wastewater. The samples deposited using the inorganic precursor show higher roughness, and this proves to be the most important factor that influences the phocatalytic processes. After 8 hours of ultraviolet irradiation, methylene blue removal efficiencies up to 36% were observed; the highest removal efficiency was registered using the thin titanium dioxide film obtained using the titanium chloride precursor, deposited on fluorine doped tin oxide glass substrate, due to the titanium dioxide-tin dioxide semiconductor tandem formed at the interface, that limits the electron-hole recombination, thus increasing the photoctalytic performance of the substrate.</p></abstract>

Photocatalytic degradation of organic pollutants from wastewater using titanium dioxide is recognized as an efficient process. To be feasible, this process needs to be solar- or visible light -activated, but, due to its wide band gap energy, titanium dioxide can only be activated by ultraviolet radiation. In this paper, thin films of titanium dioxide were deposited by Spray Pyrolysis Deposition using organo-metallic (titanium-iso-propoxide) and inorganic (titanium chloride) precursors, as a first step in optimizing the deposition process of titanium dioxide - carbon composite thin films, active in the visible spectral range. The thin films were characterized to outline the differences when using these two precursor solutions, when deposited on Fluorine doped Tin Oxide-glass, regular glass and microscopic glass, in terms of crystallinity (by using X-ray diffraction), elemental composition (using Energy Dispersive X-ray spectrometry), surface morphology (Scanning Electronic Microscopy and Atomic Force Microscopy). The photocatalytic activity of the titanium dioxide thin films was investigated based on the removal efficiencies of methylene blue from a synthetically prepared wastewater. The samples deposited using the inorganic precursor show higher roughness, and this proves to be the most important factor that influences the phocatalytic processes. After 8 hours of ultraviolet irradiation, methylene blue removal efficiencies up to 36% were observed; the highest removal efficiency was registered using the thin titanium dioxide film obtained using the titanium chloride precursor, deposited on fluorine doped tin oxide glass substrate, due to the titanium dioxide-tin dioxide semiconductor tandem formed at the interface, that limits the electron-hole recombination, thus increasing the photoctalytic performance of the substrate.

The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO<sub>2</sub> Photocatalytic Thin Films

R&D Center Renewable Energy System and Recycling

Annals of West University of Timisoara - Physics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO Photocatalytic Thin Films

Photocatalytic degradation of organic pollutants from wastewater using titanium dioxide is recognized as an efficient process. To be feasible, this process...

The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO₂ Photocatalytic Thin Films

Published Online: Aug 29, 2018

Page range: 75 - 87

Received: Mar 15, 2018

Accepted: Jun 17, 2018

DOI: https://doi.org/10.2478/awutp-2018-0008

Keywords
Titanium dioxide, Thin film, Spray pyrolysis deposition, Photocatalysis

© 2018 Ioana Tismanar et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO2 Photocatalytic Thin Films

Published Online: Aug 29, 2018

Page range: 75 - 87

Received: Mar 15, 2018

Accepted: Jun 17, 2018

DOI: https://doi.org/10.2478/awutp-2018-0008

KeywordsTitanium dioxide, Thin film, Spray pyrolysis deposition, Photocatalysis

© 2018 Ioana Tismanar et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO₂ Photocatalytic Thin Films

Keywords
Titanium dioxide, Thin film, Spray pyrolysis deposition, Photocatalysis