Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition
This work presents the evaluation of the photocatalytic activity of P25 TiO<sub>2</sub> particles, coated with SiO<sub>2</sub>, using atomic layer deposition (ALD) for the photocatalytic removal of methylene blue, oxidation of methanol and inactivation of <i>Escherichia...
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MDPI AG
2020-04-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/10/4/450 |
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| author | Miguel Martín-Sómer Dominik Benz J. Ruud van Ommen Javier Marugán |
| author_facet | Miguel Martín-Sómer Dominik Benz J. Ruud van Ommen Javier Marugán |
| author_sort | Miguel Martín-Sómer |
| collection | DOAJ |
| description | This work presents the evaluation of the photocatalytic activity of P25 TiO<sub>2</sub> particles, coated with SiO<sub>2</sub>, using atomic layer deposition (ALD) for the photocatalytic removal of methylene blue, oxidation of methanol and inactivation of <i>Escherichia coli</i> bacteria in water and its comparative evaluation with bare P25 TiO<sub>2</sub>. Two different reactor configurations were used, a slurry reactor with the catalyst in suspension, and a structured reactor with the catalyst immobilized in macroporous foams, that enables the long-term operation of the process in continuous mode, without the necessity of separation of the particles. The results show that the incorporation of SiO<sub>2</sub> decreases the efficiency of the photocatalytic oxidation of methanol, whereas a significant improvement in the removal of methylene blue is achieved, and no significant changes are observed in the photocatalytic inactivation of bacteria. Adsorption tests showed that the improvements, observed in the removal of methylene blue by the incorporation of SiO<sub>2</sub>, was mainly due to an increase in its adsorption. The improvement in the adsorption step as part of the global photocatalytic process led to a significant increase in its removal efficiency. Similar conclusions were reached for bacterial inactivation where the loss of photocatalytic efficiency, suggested by the methanol oxidation tests, was counteracted with a better adherence of bacteria to the catalyst that improved its elimination. With respect to the use of macroporous foams as support, a reduction in the photocatalytic efficiency is observed, as expected from the decrease in the available surface area. Nevertheless, this lower efficiency can be counteracted by the operational improvement derived from the easy catalyst reuse. |
| first_indexed | 2024-03-10T20:18:41Z |
| format | Article |
| id | doaj.art-bcb0fe30d4a74b449abbcc0de4a5762d |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T20:18:41Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-bcb0fe30d4a74b449abbcc0de4a5762d2023-11-19T22:20:53ZengMDPI AGCatalysts2073-43442020-04-0110445010.3390/catal10040450Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer DepositionMiguel Martín-Sómer0Dominik Benz1J. Ruud van Ommen2Javier Marugán3Department of Chemical and Environmental Technology, Universidad Rey Juan Carlos, C/Tulipán s/n, 28933 Móstoles, Madrid, SpainDepartment of Chemical Engineering, Delft University of Technology, Mekelweg 5, 2628 CD Delft, The NetherlandsDepartment of Chemical Engineering, Delft University of Technology, Mekelweg 5, 2628 CD Delft, The NetherlandsDepartment of Chemical and Environmental Technology, Universidad Rey Juan Carlos, C/Tulipán s/n, 28933 Móstoles, Madrid, SpainThis work presents the evaluation of the photocatalytic activity of P25 TiO<sub>2</sub> particles, coated with SiO<sub>2</sub>, using atomic layer deposition (ALD) for the photocatalytic removal of methylene blue, oxidation of methanol and inactivation of <i>Escherichia coli</i> bacteria in water and its comparative evaluation with bare P25 TiO<sub>2</sub>. Two different reactor configurations were used, a slurry reactor with the catalyst in suspension, and a structured reactor with the catalyst immobilized in macroporous foams, that enables the long-term operation of the process in continuous mode, without the necessity of separation of the particles. The results show that the incorporation of SiO<sub>2</sub> decreases the efficiency of the photocatalytic oxidation of methanol, whereas a significant improvement in the removal of methylene blue is achieved, and no significant changes are observed in the photocatalytic inactivation of bacteria. Adsorption tests showed that the improvements, observed in the removal of methylene blue by the incorporation of SiO<sub>2</sub>, was mainly due to an increase in its adsorption. The improvement in the adsorption step as part of the global photocatalytic process led to a significant increase in its removal efficiency. Similar conclusions were reached for bacterial inactivation where the loss of photocatalytic efficiency, suggested by the methanol oxidation tests, was counteracted with a better adherence of bacteria to the catalyst that improved its elimination. With respect to the use of macroporous foams as support, a reduction in the photocatalytic efficiency is observed, as expected from the decrease in the available surface area. Nevertheless, this lower efficiency can be counteracted by the operational improvement derived from the easy catalyst reuse.https://www.mdpi.com/2073-4344/10/4/450atomic layer depositionwater treatmentphotocatalysisTiO<sub>2</sub>-SiO<sub>2</sub>immobilized photocatalystmethylene blue adsorption |
| spellingShingle | Miguel Martín-Sómer Dominik Benz J. Ruud van Ommen Javier Marugán Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition Catalysts atomic layer deposition water treatment photocatalysis TiO<sub>2</sub>-SiO<sub>2</sub> immobilized photocatalyst methylene blue adsorption |
| title | Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition |
| title_full | Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition |
| title_fullStr | Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition |
| title_full_unstemmed | Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition |
| title_short | Multitarget Evaluation of the Photocatalytic Activity of P25-SiO<sub>2</sub> Prepared by Atomic Layer Deposition |
| title_sort | multitarget evaluation of the photocatalytic activity of p25 sio sub 2 sub prepared by atomic layer deposition |
| topic | atomic layer deposition water treatment photocatalysis TiO<sub>2</sub>-SiO<sub>2</sub> immobilized photocatalyst methylene blue adsorption |
| url | https://www.mdpi.com/2073-4344/10/4/450 |
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