Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping
TiO2 is the most studied photocatalyst for the treatment of pollutants; however, its rather large band gap and the need for a removal step when used as a suspension hinder the wide application of this technology. Immobilized TiO2 films grown by cathodic arc deposition (CAD) have shown superior adhes...
| Autores principales: | , , , , , |
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| Formato: | Documento de conferencia publisherVersion |
| Lenguaje: | Inglés |
| Publicado: |
2024
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| Acceso en línea: | https://www.wcce11.org/wc/template/Proceedings-Abstracts_WCCE11.pdf? http://hdl.handle.net/20.500.12272/11078 |
| Aporte de: |
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I68-R174-20.500.12272-11078 |
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dspace |
| institution |
Universidad Tecnológica Nacional |
| institution_str |
I-68 |
| repository_str |
R-174 |
| collection |
RIA - Repositorio Institucional Abierto (UTN) |
| language |
Inglés |
| topic |
TiO2 Cathodic arc N-doping Cr(VI) |
| spellingShingle |
TiO2 Cathodic arc N-doping Cr(VI) Kleiman, Ariel Meichtry, Jorge Martín Xaubet, M. Grondona, D. Litter, Marta Irene Márquez, Adriana Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| topic_facet |
TiO2 Cathodic arc N-doping Cr(VI) |
| description |
TiO2 is the most studied photocatalyst for the treatment of pollutants; however, its rather large band gap and the need for a removal step when used as a suspension hinder the wide application of this technology. Immobilized TiO2 films grown by cathodic arc deposition (CAD) have shown superior adhesion to the substrate and activities similar to that of P-25 TiO2 films, the reference photocatalyst, but they still require UV light to be excited [1]. N-doping is a strategy frequently used to extend the TiO2 band gap to the visible range [2], but it has a scarce application on CAD-grown films. In this work, TiO2 CAD films, with and without N-doping, were prepared and tested on the photocatalytic removal of Cr(VI), a priority water pollutant, in the presence of ethylenediaminetetraacetic acid (EDTA) as an organic donor.
TiO2 films of different thicknesses: (290 ± 40 nm), (440 ± 40) nm, and (850 ± 70) nm, were deposited by CAD according to a reported method [1]. The doping of the films was performed by plasma immersion ion implantation in a N2 environment. For comparison, P-25 TiO2 films of (280 ± 20) nm and (480 ± 30) nm thicknesses were prepared by dip-coating; thicker P-25 films were not stable. All films were grown over a borosilicate glass substrate. Photocatalytic experiments were performed in thermostatted cylindrical glass cells (T = 25 °C) magnetically stirred and irradiated from the top with a HPA 400S lamp (λ > 320 nm, mean UV irradiance 28 W m-2), equipped with an IR filter. 10 mL of a 0.8 mM Cr(VI) and 1 mM EDTA solution at pH 2 (HClO4) were poured into each cell, and 0.25 mL samples were periodically taken for Cr(VI) quantification by the diphenylcarbazide method; at the end of the experiments, a Cr(III)-EDTA complex in solution was determined by direct spectrophotometry [1].
After 5 h of irradiation, Cr(VI) removals of 58% and 85% were obtained with pure and N-doped 290 nm CAD films, respectively, while for pure and N-doped 440 nm CAD films the corresponding removals were 70% and 85%; with the 280 nm and 480 nm P-25 films, Cr(VI) removals were 81% and 88%, respectively. Although thicker CAD films were more efficient (99% of Cr(VI) removal with 850 nm films), no difference could be appreciated between N-doped and undoped films. Cr(VI) evolution could be adjusted to a pseudo-first-order kinetics. In all cases, Cr(III)-EDTA represented 75% of the reduced Cr(VI), the remaining Cr(III) being retained on the TiO2 surface, [1].
The photocatalytic efficiency increased with the thickness of the films. Although P-25 films showed a higher photoactivity than the CAD films of similar thickness, thicker and more active CAD films can be surely obtained in future works. N-doping increased slightly the photocatalytic activity of the thinnest films. |
| format |
Documento de conferencia publisherVersion |
| author |
Kleiman, Ariel Meichtry, Jorge Martín Xaubet, M. Grondona, D. Litter, Marta Irene Márquez, Adriana |
| author_facet |
Kleiman, Ariel Meichtry, Jorge Martín Xaubet, M. Grondona, D. Litter, Marta Irene Márquez, Adriana |
| author_sort |
Kleiman, Ariel |
| title |
Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| title_short |
Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| title_full |
Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| title_fullStr |
Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| title_full_unstemmed |
Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping |
| title_sort |
preliminary results of photocatalytic cr(vi) reduction using tio2 films grown by cathodic arc deposition: effect of the film thickness and the n-doping |
| publishDate |
2024 |
| url |
https://www.wcce11.org/wc/template/Proceedings-Abstracts_WCCE11.pdf? http://hdl.handle.net/20.500.12272/11078 |
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1809230353978621952 |
| spelling |
I68-R174-20.500.12272-110782024-07-04T20:31:41Z Preliminary results of photocatalytic Cr(VI) reduction using TiO2 films grown by cathodic arc deposition: effect of the film thickness and the N-doping Kleiman, Ariel Meichtry, Jorge Martín Xaubet, M. Grondona, D. Litter, Marta Irene Márquez, Adriana TiO2 Cathodic arc N-doping Cr(VI) TiO2 is the most studied photocatalyst for the treatment of pollutants; however, its rather large band gap and the need for a removal step when used as a suspension hinder the wide application of this technology. Immobilized TiO2 films grown by cathodic arc deposition (CAD) have shown superior adhesion to the substrate and activities similar to that of P-25 TiO2 films, the reference photocatalyst, but they still require UV light to be excited [1]. N-doping is a strategy frequently used to extend the TiO2 band gap to the visible range [2], but it has a scarce application on CAD-grown films. In this work, TiO2 CAD films, with and without N-doping, were prepared and tested on the photocatalytic removal of Cr(VI), a priority water pollutant, in the presence of ethylenediaminetetraacetic acid (EDTA) as an organic donor. TiO2 films of different thicknesses: (290 ± 40 nm), (440 ± 40) nm, and (850 ± 70) nm, were deposited by CAD according to a reported method [1]. The doping of the films was performed by plasma immersion ion implantation in a N2 environment. For comparison, P-25 TiO2 films of (280 ± 20) nm and (480 ± 30) nm thicknesses were prepared by dip-coating; thicker P-25 films were not stable. All films were grown over a borosilicate glass substrate. Photocatalytic experiments were performed in thermostatted cylindrical glass cells (T = 25 °C) magnetically stirred and irradiated from the top with a HPA 400S lamp (λ > 320 nm, mean UV irradiance 28 W m-2), equipped with an IR filter. 10 mL of a 0.8 mM Cr(VI) and 1 mM EDTA solution at pH 2 (HClO4) were poured into each cell, and 0.25 mL samples were periodically taken for Cr(VI) quantification by the diphenylcarbazide method; at the end of the experiments, a Cr(III)-EDTA complex in solution was determined by direct spectrophotometry [1]. After 5 h of irradiation, Cr(VI) removals of 58% and 85% were obtained with pure and N-doped 290 nm CAD films, respectively, while for pure and N-doped 440 nm CAD films the corresponding removals were 70% and 85%; with the 280 nm and 480 nm P-25 films, Cr(VI) removals were 81% and 88%, respectively. Although thicker CAD films were more efficient (99% of Cr(VI) removal with 850 nm films), no difference could be appreciated between N-doped and undoped films. Cr(VI) evolution could be adjusted to a pseudo-first-order kinetics. In all cases, Cr(III)-EDTA represented 75% of the reduced Cr(VI), the remaining Cr(III) being retained on the TiO2 surface, [1]. The photocatalytic efficiency increased with the thickness of the films. Although P-25 films showed a higher photoactivity than the CAD films of similar thickness, thicker and more active CAD films can be surely obtained in future works. N-doping increased slightly the photocatalytic activity of the thinnest films. 1. Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, CABA, Argentina. 2. Universidad de Buenos Aires-CONICET, Instituto de Física del Plasma (INFIP), Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria Pab. I, 1428, CABA, Argentina. 3. Centro de Tecnologías Químicas, FRBA-UTN, Medrano 951, C1179AAQ, CABA, Argentina. 4. DQRA, Gerencia Química, CNEA-CONICET, Av. Gral. Paz 1499, 1650 San Martín, Buenos Aires, Argentina. 5. IIIA-UNSAM-CONICET, Institute of Environmental Research and Engineering, Habitat and Sustainability School, National University of San Martín-CONICET, Campus Miguelete, Av. 25 de Mayo y Francia, 1650 San Martín, Prov. de Buenos Aires, Argentina. 2024-07-04T20:31:41Z 2024-07-04T20:31:41Z 2023-06-08 info:eu-repo/semantics/conferenceObject publisherVersion https://www.wcce11.org/wc/template/Proceedings-Abstracts_WCCE11.pdf? http://hdl.handle.net/20.500.12272/11078 eng PID-UTN MSTCBA0008699 openAccess Open Access msword |