Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation
The size of TiO<sub>2</sub> can significantly affect both its photocatalytic and photo-electrochemical properties, thus altering the photooxidation of organic pollutants in air or water. In this work, we give an account of the photo-electrochemical and photocatalytic features of some nan...
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2021-03-01
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| author | Damián Monllor-Satoca Pedro Bonete Ridha Djellabi Giuseppina Cerrato Lorenza Operti Roberto Gómez Claudia Letizia Bianchi |
| author_facet | Damián Monllor-Satoca Pedro Bonete Ridha Djellabi Giuseppina Cerrato Lorenza Operti Roberto Gómez Claudia Letizia Bianchi |
| author_sort | Damián Monllor-Satoca |
| collection | DOAJ |
| description | The size of TiO<sub>2</sub> can significantly affect both its photocatalytic and photo-electrochemical properties, thus altering the photooxidation of organic pollutants in air or water. In this work, we give an account of the photo-electrochemical and photocatalytic features of some nanosized TiO<sub>2</sub> commercial powders towards a model reaction, the photooxidation of acetone. Cyclic voltammograms (CV) of TiO<sub>2</sub> particulate electrodes under UV illumination experiments were carried out in either saturated O<sub>2</sub> or N<sub>2</sub> solutions for a direct correlation with the photocatalytic process. In addition, the effect of different reaction conditions on the photocatalytic efficiency under UV light in both aqueous and gaseous phases was also investigated. CV curves with the addition of acetone under UV light showed a negative shift of the photocurrent onset, confirming the efficient transfer of photoproduced reactive oxygen species (ROSs), e.g., hydroxyl radicals or holes to acetone molecules. The photocatalytic experiments showed that the two nano-sized samples exhibit the best photocatalytic performance. The different photoactivity of the larger-sized samples is probably attributed to their morphological differences, affecting both the amount and distribution of free ROSs involved in the photooxidation reaction. Finally, a direct correlation between the photocatalytic measurements in gas phase and the photo-electrochemical measurements in aqueous phase is given, thus evincing the important role of the substrate-surface interaction with similar acetone concentrations. |
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| language | English |
| last_indexed | 2024-03-10T13:26:37Z |
| publishDate | 2021-03-01 |
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| spelling | doaj.art-ec7719d524184de58c0070a2bdd950352023-11-21T09:39:41ZengMDPI AGCatalysts2073-43442021-03-0111334910.3390/catal11030349Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants OxidationDamián Monllor-Satoca0Pedro Bonete1Ridha Djellabi2Giuseppina Cerrato3Lorenza Operti4Roberto Gómez5Claudia Letizia Bianchi6Institut Universitari d’Electroquímica i Departament de Química Física, Universitat d’Alacant, Apartat 99, E-03080 Alacant, SpainInstitut Universitari d’Electroquímica i Departament de Química Física, Universitat d’Alacant, Apartat 99, E-03080 Alacant, SpainDipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, 20133 Milano, ItalyDipartimento di Chimica & NIS Centre of Excellence, Università degli Studi di Torino, via Giuria 7, 10125 Torino, ItalyDipartimento di Chimica & NIS Centre of Excellence, Università degli Studi di Torino, via Giuria 7, 10125 Torino, ItalyInstitut Universitari d’Electroquímica i Departament de Química Física, Universitat d’Alacant, Apartat 99, E-03080 Alacant, SpainDipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, 20133 Milano, ItalyThe size of TiO<sub>2</sub> can significantly affect both its photocatalytic and photo-electrochemical properties, thus altering the photooxidation of organic pollutants in air or water. In this work, we give an account of the photo-electrochemical and photocatalytic features of some nanosized TiO<sub>2</sub> commercial powders towards a model reaction, the photooxidation of acetone. Cyclic voltammograms (CV) of TiO<sub>2</sub> particulate electrodes under UV illumination experiments were carried out in either saturated O<sub>2</sub> or N<sub>2</sub> solutions for a direct correlation with the photocatalytic process. In addition, the effect of different reaction conditions on the photocatalytic efficiency under UV light in both aqueous and gaseous phases was also investigated. CV curves with the addition of acetone under UV light showed a negative shift of the photocurrent onset, confirming the efficient transfer of photoproduced reactive oxygen species (ROSs), e.g., hydroxyl radicals or holes to acetone molecules. The photocatalytic experiments showed that the two nano-sized samples exhibit the best photocatalytic performance. The different photoactivity of the larger-sized samples is probably attributed to their morphological differences, affecting both the amount and distribution of free ROSs involved in the photooxidation reaction. Finally, a direct correlation between the photocatalytic measurements in gas phase and the photo-electrochemical measurements in aqueous phase is given, thus evincing the important role of the substrate-surface interaction with similar acetone concentrations.https://www.mdpi.com/2073-4344/11/3/349nanosized TiO<sub>2</sub>photocatalytic efficiencyphoto-electrochemical characterizationenvironmental remediation |
| spellingShingle | Damián Monllor-Satoca Pedro Bonete Ridha Djellabi Giuseppina Cerrato Lorenza Operti Roberto Gómez Claudia Letizia Bianchi Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation Catalysts nanosized TiO<sub>2</sub> photocatalytic efficiency photo-electrochemical characterization environmental remediation |
| title | Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation |
| title_full | Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation |
| title_fullStr | Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation |
| title_full_unstemmed | Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation |
| title_short | Comparative Photo-Electrochemical and Photocatalytic Studies with Nanosized TiO<sub>2</sub> Photocatalysts towards Organic Pollutants Oxidation |
| title_sort | comparative photo electrochemical and photocatalytic studies with nanosized tio sub 2 sub photocatalysts towards organic pollutants oxidation |
| topic | nanosized TiO<sub>2</sub> photocatalytic efficiency photo-electrochemical characterization environmental remediation |
| url | https://www.mdpi.com/2073-4344/11/3/349 |
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