Exploring the effect of the irradiation time on photosensitized dendrimer-based nanoaggregates for potential applications in light-driven water photoreduction
Por:
Martínez N.P., Inostroza-Rivera R., Durán B., Molero L., Bonardd S., Ramírez O., Isaacs M., Díaz D.D., Leiva A., Saldías C.
Publicada:
1 ene 2019
Resumen:
Fourth generation polyamidoamine dendrimer (PAMAM, G4) modified with fluorescein units (F) at the periphery and Pt nanoparticles stabilized by L-ascorbate were prepared. These dendrimers modified with hydrophobic fluorescein were used to achieve self-assembling structures, giving rise to the formation of nanoaggregates in water. The photoactive fluorescein units were mainly used as photosensitizer units in the process of the catalytic photoreduction of water propitiated by light. Complementarily, Pt-ascorbate nanoparticles acted as the active sites to generate H2. Importantly, the study of the functional, optical, surface potential and morphological properties of the photosensitized dendrimer aggregates at different irradiation times allowed for insights to be gained into the behavior of these systems. Thus, the resultant photosensitized PAMAM-fluorescein (G4-F) nanoaggregates (NG) were conveniently applied to light-driven water photoreduction along with sodium L-ascorbate and methyl viologen as the sacrificial reagent and electron relay agent, respectively. Notably, these aggregates exhibited appropriate stability and catalytic activity over time for hydrogen production. Additionally, in order to propose a potential use of these types of systems, the in situ generated H2 was able to reduce a certain amount of methylene blue (MB). Finally, theoretical electronic analyses provided insights into the possible excited states of the fluorescein molecules that could intervene in the global mechanism of H2 generation. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.
Filiaciones:
Martínez N.P.:
Departamento de Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, Macul, 7820436, Chile
Inostroza-Rivera R.:
Facultad de Ciencias de la Salud, Universidad Arturo Prat, Iquique, 1100000, Chile
Durán B.:
Centro de Investigación en Nanotecnología y Materiales Avanzados, Pontificia Universidad Católica de Chile, Macul, 7820436, Chile
Molero L.:
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago, 8320000, Chile
Bonardd S.:
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago, 8320000, Chile
Ramírez O.:
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago, 8320000, Chile
Isaacs M.:
Departamento de Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago, Macul, 7820436, Chile
Centro de Investigación en Nanotecnología y Materiales Avanzados, Pontificia Universidad Católica de Chile, Macul, 7820436, Chile
Díaz D.D.:
Institut für Organische Chemie, Universität Regensburg, Universitätsstr. 31, Regensburg, 93053, Germany
Instituto de Productos Naturales y Agrobiología del CSIC, Avda. Astrofísico Francisco Sánchez 3, La Laguna, Tenerife 38206, Spain
Leiva A.:
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago, 8320000, Chile
Saldías C.:
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago, 8320000, Chile
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