Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation
Four silver phosphate-based materials were successfully synthesized, characterized, and evaluated, together with TiO<sub>2</sub>, in the photodegradation of synthetic dyes (tartrazine, Orange II, rhodamine, and Brilliant Blue FCF) under two irradiation sources centered at 420 and 450 nm....
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MDPI AG
2020-07-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/10/7/774 |
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| author | Alice Pavanello Alejandro Blasco Peter F. Johnston Miguel A. Miranda Maria Luisa Marin |
| author_facet | Alice Pavanello Alejandro Blasco Peter F. Johnston Miguel A. Miranda Maria Luisa Marin |
| author_sort | Alice Pavanello |
| collection | DOAJ |
| description | Four silver phosphate-based materials were successfully synthesized, characterized, and evaluated, together with TiO<sub>2</sub>, in the photodegradation of synthetic dyes (tartrazine, Orange II, rhodamine, and Brilliant Blue FCF) under two irradiation sources centered at 420 and 450 nm. Scanning Electron Microscopy (SEM) images showed different topologies of the synthesized materials, whereas diffuse reflectance spectra demonstrated that they display absorption up to 500 nm. Degradation experiments were performed in parallel with the silver materials and TiO<sub>2</sub>. Upon irradiation centered at 420 nm, the abatement of the dyes was slightly more efficient in the case of TiO<sub>2</sub>—except for Orange II. Nevertheless, upon irradiation centered at 450 nm, TiO<sub>2</sub> demonstrated complete inefficiency and silver phosphates accomplished the complete abatement of the dyes—except for Brilliant Blue FCF. A careful analysis of the achieved degradation of dyes revealed that the main reaction mechanism involves electron transfer to the photogenerated holes in the valence band of silver photocatalysts, together with the direct excitation of dyes and the subsequent formation of reactive species. The performance of TiO<sub>2</sub> was only comparable at the shorter wavelength when hydroxyl radicals could be formed; however, it could not compete under irradiation at 450 nm since the formed superoxide anion is not as reactive as hydroxyl radicals. |
| first_indexed | 2024-03-10T18:32:26Z |
| format | Article |
| id | doaj.art-3d7b74acfd56438e8ffcddf9dee15496 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T18:32:26Z |
| publishDate | 2020-07-01 |
| publisher | MDPI AG |
| record_format | Article |
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| spelling | doaj.art-3d7b74acfd56438e8ffcddf9dee154962023-11-20T06:29:35ZengMDPI AGCatalysts2073-43442020-07-0110777410.3390/catal10070774Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light IrradiationAlice Pavanello0Alejandro Blasco1Peter F. Johnston2Miguel A. Miranda3Maria Luisa Marin4Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022 Valencia, SpainInstituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022 Valencia, SpainInstituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022 Valencia, SpainInstituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022 Valencia, SpainInstituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022 Valencia, SpainFour silver phosphate-based materials were successfully synthesized, characterized, and evaluated, together with TiO<sub>2</sub>, in the photodegradation of synthetic dyes (tartrazine, Orange II, rhodamine, and Brilliant Blue FCF) under two irradiation sources centered at 420 and 450 nm. Scanning Electron Microscopy (SEM) images showed different topologies of the synthesized materials, whereas diffuse reflectance spectra demonstrated that they display absorption up to 500 nm. Degradation experiments were performed in parallel with the silver materials and TiO<sub>2</sub>. Upon irradiation centered at 420 nm, the abatement of the dyes was slightly more efficient in the case of TiO<sub>2</sub>—except for Orange II. Nevertheless, upon irradiation centered at 450 nm, TiO<sub>2</sub> demonstrated complete inefficiency and silver phosphates accomplished the complete abatement of the dyes—except for Brilliant Blue FCF. A careful analysis of the achieved degradation of dyes revealed that the main reaction mechanism involves electron transfer to the photogenerated holes in the valence band of silver photocatalysts, together with the direct excitation of dyes and the subsequent formation of reactive species. The performance of TiO<sub>2</sub> was only comparable at the shorter wavelength when hydroxyl radicals could be formed; however, it could not compete under irradiation at 450 nm since the formed superoxide anion is not as reactive as hydroxyl radicals.https://www.mdpi.com/2073-4344/10/7/774conduction bandholehydroxyl radicalmechanismsuperoxide aniontitanium dioxide |
| spellingShingle | Alice Pavanello Alejandro Blasco Peter F. Johnston Miguel A. Miranda Maria Luisa Marin Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation Catalysts conduction band hole hydroxyl radical mechanism superoxide anion titanium dioxide |
| title | Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation |
| title_full | Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation |
| title_fullStr | Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation |
| title_full_unstemmed | Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation |
| title_short | Enhanced Photodegradation of Synthetic Dyes Mediated by Ag<sub>3</sub>PO<sub>4</sub>-Based Semiconductors under Visible Light Irradiation |
| title_sort | enhanced photodegradation of synthetic dyes mediated by ag sub 3 sub po sub 4 sub based semiconductors under visible light irradiation |
| topic | conduction band hole hydroxyl radical mechanism superoxide anion titanium dioxide |
| url | https://www.mdpi.com/2073-4344/10/7/774 |
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