Aldo Talon | Università Ca' Foscari Venezia (original) (raw)

Papers by Aldo Talon

XXV Reunión Científica de la Sociedad Española de Arcillas, 2018

A new synthesised triphenylamine-based dye was anchored to mesoporous pure anatase TiO2 thorough ... more A new synthesised triphenylamine-based dye was anchored to mesoporous pure anatase TiO2 thorough the OH-ending branch of its first generation dendritic structure. We present the optical properties of the dye-titania hybrid material and compare its performances with those of the same sensitizer on the commercial Degussa P25, which contains a rutile phase component. The optical and chemical properties of the dye make it a promising candidate as a metal-free dye for DSSCs.

Sesiones de pósters: Los pósters correspondientes a la primera sesión podrán colocarse a partir d... more Sesiones de pósters: Los pósters correspondientes a la primera sesión podrán colocarse a partir del domingo 1 de julio y deben retirarse durante la mañana del martes 3 de julio. A partir de las 12h del 3 de julio se podrán colgar los pósters correspondientes a la 2ª sesión.

International Journal of Hydrogen Energy, 2018

Gold nanoparticles precipitated-deposited on titania nanostructures (1.0 wt% nominal loading) wer... more Gold nanoparticles precipitated-deposited on titania nanostructures (1.0 wt% nominal loading) were studied in the preferential CO oxidation in excess of H 2 at room temperature and atmospheric pressure, both in dark and under simulated solar light irradiation. Titania supports were synthesized by means of two hydrothermal methods markedly acid and basic, giving rise to rutile nanorods and anatase deformed nanorods structures, respectively. Characterization techniques such as N 2 physisorption, XRD, XPS, DRUV-vis, HRTEM and XRF were performed in order to study the chemical, structural and optical properties of the catalysts. Well defined rutile nanorods structures were obtained from the acidic treatment allowing a regular distribution of gold nanoparticles and resulting quite active in the CO-PROX reaction. In particular the sample from the acidic synthetic approach calcined at 700 C displayed the best results as it was highly selective to CO 2 under both dark and simulated solar light irradiation.

Applied Surface Science, 2021

Abstract We investigated the effect of copper doping on the photocatalytic properties of TiO2 thi... more Abstract We investigated the effect of copper doping on the photocatalytic properties of TiO2 thin films. Titania thin films doped with three different copper concentrations were synthesized via radiofrequency-assisted (RF) magnetron sputtering, then annealed at 600 °C in controlled atmosphere (Ar, O2, H2 flow). The impact of the annealing in inert, oxidizing or reducing atmosphere on the crystalline and surface structure, and photocatalytic performance in the methylene blue degradation under UV light irradiation was investigated by X-ray diffraction, UV-Vis Spectroscopy, Rutherford Backscattering Spectrometry, electron scanning microscopy. Annealing induced very different crystallization in different atmospheres, with strong copper out-diffusion in samples annealed in reducing atmosphere and formation of large embedded nanoparticles. The Cu-doped titania films exhibited higher photocatalytic activity than pure titania film and the best performing catalyst, treated in H2 atmosphere, suggests that the presence of embedded copper nanoparticles (both metallic and oxidized) is able to strongly enhance the photocatalytic properties of the host titania matrix. Incorporated Cu particles can act as trapped sites for generated electrons, and this leads to the reduction of carrier recombination which, ultimately, plays a significant role in the increase of photoactivity. The recyclability of the best system was ascertained by a suitable 3-cycle stability test.

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A structurally organized mesoporous CuO/CeO 2 /Al 2 O 3 catalyst (8.3 % CuO, 17.0 % CeO 2) was pr... more A structurally organized mesoporous CuO/CeO 2 /Al 2 O 3 catalyst (8.3 % CuO, 17.0 % CeO 2) was prepared by a new single-step template sol-gel synthesis, characterized by TGA, XRD, N 2 adsorption and TPR, and tested for oxidative steam reforming of methanol (OSRM) at T = 200-400°C, H 2 O/CH 3 OH/O 2 molar ratios = 1.1/1/0.12, CH 3 OH concentration = 17.8%, GHSV = 6×10 4 h −1. The catalyst contained Cu 2+ species strongly interacting with CeO 2 , besides a CuO phase highly dispersed in alumina. After reduction in H 2 the catalyst, compared with more conventional CuO/CeO 2 systems, showed good activity and H 2 yield in the OSRM process.

Since the discovery in 1972, by Fujishima and Honda, of water splitting by using TiO2 under UV ir... more Since the discovery in 1972, by Fujishima and Honda, of water splitting by using TiO2 under UV irradiation, photocatalysis has gained interest in energy and environment fields worldwide. Nowadays, photocatalysis is an extensively studied field for pollutants degradation as well as for environmental remediation, inasmuch as these reactions can be accomplished at mild operating conditions and can be solar driven. Titania, specially anatase phase, is regarded as one of the most promising photocatalysts thanks to its high stability, optical properties, availability and non-toxicity. Nonetheless, the use of this semiconductor as a photocatalyst is limited by its wide band gap, as it requires wavelengths close to UV. Considering that approximately 5% of solar light consists in UV, one of the greatest challenges for photocatalysis hints at the development of catalysts active in the visible light scope, which stands for 43% of the incident solar spectrum. Nanoparticles of noble metals such ...

have shown promising properties in terms of activity, selectivity and resistance to CO 2 and H 2O... more have shown promising properties in terms of activity, selectivity and resistance to CO 2 and H 2O. In this work, a series of Ce–Zr–Cu mixed oxide systems, with different atomic ratios among cations, were prepared by slow co-precipitation with the aim to investigate the influence of the presence of very small amounts of zirconium on the performances of these three-component catalysts. The activity of these materials was evaluated in the CO preferential oxidation in hydrogen-rich gas stream (1.2% CO, 1.2% O2, 50% H2, He balance) in the absence and presence of CO2 and H 2O, in the 40-190°C temperature range. Correlations between catalytic activity and physico-chemical properties of the materials were made by X-ray Powder Diffraction (XRPD), N2 physisorption, TemperatureProgrammed Reduction (H2-TPR), X-ray Photoelectron Spectroscopy (XPS).

In view of the stringent CO intolerance of the proton-exchange membrane fuel cells (PEMFCs), it i... more In view of the stringent CO intolerance of the proton-exchange membrane fuel cells (PEMFCs), it is essential to eliminate even trace amounts of carbon monoxide from the reformate streams. The preferential oxidation (PROX) is considered to be a promising method for CO cleaning up. Catalytic systems, based on copper supported on ceria-modified organized mesoporous alumina, were investigated for the PROX of CO in hydrogen-rich gas stream. The catalysts showed an interesting activity in the CO-PROX. The sample with the best catalytic performance was characterized by N 2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRPD), high-resolution transmission electron microscopy (HRTEM), temperature-programmed reduction by H 2 (H 2-TPR), and successive re-oxidation (TPO).

Hierarchical Zn-ZSM-11 zeolite with an olive-shaped intergrowth morphology was synthesized via a ... more Hierarchical Zn-ZSM-11 zeolite with an olive-shaped intergrowth morphology was synthesized via a novel and facile one-step hydrothermal method by using tetrabutylammonium bromide (TBABr) and zinc oxide (ZnO) as a difunctional template and zinc source, respectively. Structural characterizations (XRD, IR, TG-DTA, SEM, and N 2 adsorption-desorption) were conducted to analyze the textural properties of Zn-ZSM-11 samples. Compared with the Zn containing ZSM-11 samples prepared by other methods (ZnSO 4 method, ZnO-impregnated-seed method and impregnation method), the Zn-ZSM-11 prepared by ZnO method exhibited enriched mesopores as well as good catalytic activity in methanol conversion. TEM images showed that Zn species were well incorporated into the zeolite framework, while the different morphology of Zn-ZSM-11 from ZSM-11 further verified that the Zn species had been involved in the formation of ZSM-11 framework. 27 Al and 29 Si MAS NMR spectra revealed that Zn species in zeolite framework significantly impacted the coordination of Si. The XRD patterns variation of the ZnO containing gel were also tracked to illustrate the crystallization process. It was found that the ZnO would be gradually dissolved under the severely alkaline environment and subsequently incorporated into the ZSM-11 framework in the crystallization process. This facile new synthesis strategy can also be extended to prepare other Zn containing zeolites and is potentially important for practical utilization.

1. Introducción En los últimos años la protección ambiental y el uso de fuentes de energía renova... more 1. Introducción En los últimos años la protección ambiental y el uso de fuentes de energía renovables son dos objetivos principales en la investigación química. La energía solar se puede aprovechar para la degradación fotocatalítica de moléculas orgánicas contaminantes, hormonas o medicamentos, tanto en el aire, en el agua, como en las superficies, porque la luz solar es capaz de descomponerlas [1]. A pesar de la gran cantidad de aplicaciones fotocatalíticas de la titania (TiO2), fotocatalizador no tóxico, de bajo costo y muy prometedor [2], hay algunos factores críticos que limitan su fotoactividad. El principal es el valor de su salto de energía, que limita su uso como fotocatalizador en la región UV del espectro. Con el objetivo principal de extender su uso a la región visible del espectro, en literatura se ha propuesto el depósito de metales nobles en su superficie, modificaciones superficiales, así como el dopaje con iones de metales de transición o elementos de tierras raras. ...

XXV Reunión Científica de la Sociedad Española de Arcillas, 2018

A new synthesised triphenylamine-based dye was anchored to mesoporous pure anatase TiO2 thorough ... more A new synthesised triphenylamine-based dye was anchored to mesoporous pure anatase TiO2 thorough the OH-ending branch of its first generation dendritic structure. We present the optical properties of the dye-titania hybrid material and compare its performances with those of the same sensitizer on the commercial Degussa P25, which contains a rutile phase component. The optical and chemical properties of the dye make it a promising candidate as a metal-free dye for DSSCs.

Sesiones de pósters: Los pósters correspondientes a la primera sesión podrán colocarse a partir d... more Sesiones de pósters: Los pósters correspondientes a la primera sesión podrán colocarse a partir del domingo 1 de julio y deben retirarse durante la mañana del martes 3 de julio. A partir de las 12h del 3 de julio se podrán colgar los pósters correspondientes a la 2ª sesión.

International Journal of Hydrogen Energy, 2018

Gold nanoparticles precipitated-deposited on titania nanostructures (1.0 wt% nominal loading) wer... more Gold nanoparticles precipitated-deposited on titania nanostructures (1.0 wt% nominal loading) were studied in the preferential CO oxidation in excess of H 2 at room temperature and atmospheric pressure, both in dark and under simulated solar light irradiation. Titania supports were synthesized by means of two hydrothermal methods markedly acid and basic, giving rise to rutile nanorods and anatase deformed nanorods structures, respectively. Characterization techniques such as N 2 physisorption, XRD, XPS, DRUV-vis, HRTEM and XRF were performed in order to study the chemical, structural and optical properties of the catalysts. Well defined rutile nanorods structures were obtained from the acidic treatment allowing a regular distribution of gold nanoparticles and resulting quite active in the CO-PROX reaction. In particular the sample from the acidic synthetic approach calcined at 700 C displayed the best results as it was highly selective to CO 2 under both dark and simulated solar light irradiation.

Applied Surface Science, 2021

Abstract We investigated the effect of copper doping on the photocatalytic properties of TiO2 thi... more Abstract We investigated the effect of copper doping on the photocatalytic properties of TiO2 thin films. Titania thin films doped with three different copper concentrations were synthesized via radiofrequency-assisted (RF) magnetron sputtering, then annealed at 600 °C in controlled atmosphere (Ar, O2, H2 flow). The impact of the annealing in inert, oxidizing or reducing atmosphere on the crystalline and surface structure, and photocatalytic performance in the methylene blue degradation under UV light irradiation was investigated by X-ray diffraction, UV-Vis Spectroscopy, Rutherford Backscattering Spectrometry, electron scanning microscopy. Annealing induced very different crystallization in different atmospheres, with strong copper out-diffusion in samples annealed in reducing atmosphere and formation of large embedded nanoparticles. The Cu-doped titania films exhibited higher photocatalytic activity than pure titania film and the best performing catalyst, treated in H2 atmosphere, suggests that the presence of embedded copper nanoparticles (both metallic and oxidized) is able to strongly enhance the photocatalytic properties of the host titania matrix. Incorporated Cu particles can act as trapped sites for generated electrons, and this leads to the reduction of carrier recombination which, ultimately, plays a significant role in the increase of photoactivity. The recyclability of the best system was ascertained by a suitable 3-cycle stability test.

aidic.it

A structurally organized mesoporous CuO/CeO 2 /Al 2 O 3 catalyst (8.3 % CuO, 17.0 % CeO 2) was pr... more A structurally organized mesoporous CuO/CeO 2 /Al 2 O 3 catalyst (8.3 % CuO, 17.0 % CeO 2) was prepared by a new single-step template sol-gel synthesis, characterized by TGA, XRD, N 2 adsorption and TPR, and tested for oxidative steam reforming of methanol (OSRM) at T = 200-400°C, H 2 O/CH 3 OH/O 2 molar ratios = 1.1/1/0.12, CH 3 OH concentration = 17.8%, GHSV = 6×10 4 h −1. The catalyst contained Cu 2+ species strongly interacting with CeO 2 , besides a CuO phase highly dispersed in alumina. After reduction in H 2 the catalyst, compared with more conventional CuO/CeO 2 systems, showed good activity and H 2 yield in the OSRM process.

Since the discovery in 1972, by Fujishima and Honda, of water splitting by using TiO2 under UV ir... more Since the discovery in 1972, by Fujishima and Honda, of water splitting by using TiO2 under UV irradiation, photocatalysis has gained interest in energy and environment fields worldwide. Nowadays, photocatalysis is an extensively studied field for pollutants degradation as well as for environmental remediation, inasmuch as these reactions can be accomplished at mild operating conditions and can be solar driven. Titania, specially anatase phase, is regarded as one of the most promising photocatalysts thanks to its high stability, optical properties, availability and non-toxicity. Nonetheless, the use of this semiconductor as a photocatalyst is limited by its wide band gap, as it requires wavelengths close to UV. Considering that approximately 5% of solar light consists in UV, one of the greatest challenges for photocatalysis hints at the development of catalysts active in the visible light scope, which stands for 43% of the incident solar spectrum. Nanoparticles of noble metals such ...

have shown promising properties in terms of activity, selectivity and resistance to CO 2 and H 2O... more have shown promising properties in terms of activity, selectivity and resistance to CO 2 and H 2O. In this work, a series of Ce–Zr–Cu mixed oxide systems, with different atomic ratios among cations, were prepared by slow co-precipitation with the aim to investigate the influence of the presence of very small amounts of zirconium on the performances of these three-component catalysts. The activity of these materials was evaluated in the CO preferential oxidation in hydrogen-rich gas stream (1.2% CO, 1.2% O2, 50% H2, He balance) in the absence and presence of CO2 and H 2O, in the 40-190°C temperature range. Correlations between catalytic activity and physico-chemical properties of the materials were made by X-ray Powder Diffraction (XRPD), N2 physisorption, TemperatureProgrammed Reduction (H2-TPR), X-ray Photoelectron Spectroscopy (XPS).

In view of the stringent CO intolerance of the proton-exchange membrane fuel cells (PEMFCs), it i... more In view of the stringent CO intolerance of the proton-exchange membrane fuel cells (PEMFCs), it is essential to eliminate even trace amounts of carbon monoxide from the reformate streams. The preferential oxidation (PROX) is considered to be a promising method for CO cleaning up. Catalytic systems, based on copper supported on ceria-modified organized mesoporous alumina, were investigated for the PROX of CO in hydrogen-rich gas stream. The catalysts showed an interesting activity in the CO-PROX. The sample with the best catalytic performance was characterized by N 2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRPD), high-resolution transmission electron microscopy (HRTEM), temperature-programmed reduction by H 2 (H 2-TPR), and successive re-oxidation (TPO).

Hierarchical Zn-ZSM-11 zeolite with an olive-shaped intergrowth morphology was synthesized via a ... more Hierarchical Zn-ZSM-11 zeolite with an olive-shaped intergrowth morphology was synthesized via a novel and facile one-step hydrothermal method by using tetrabutylammonium bromide (TBABr) and zinc oxide (ZnO) as a difunctional template and zinc source, respectively. Structural characterizations (XRD, IR, TG-DTA, SEM, and N 2 adsorption-desorption) were conducted to analyze the textural properties of Zn-ZSM-11 samples. Compared with the Zn containing ZSM-11 samples prepared by other methods (ZnSO 4 method, ZnO-impregnated-seed method and impregnation method), the Zn-ZSM-11 prepared by ZnO method exhibited enriched mesopores as well as good catalytic activity in methanol conversion. TEM images showed that Zn species were well incorporated into the zeolite framework, while the different morphology of Zn-ZSM-11 from ZSM-11 further verified that the Zn species had been involved in the formation of ZSM-11 framework. 27 Al and 29 Si MAS NMR spectra revealed that Zn species in zeolite framework significantly impacted the coordination of Si. The XRD patterns variation of the ZnO containing gel were also tracked to illustrate the crystallization process. It was found that the ZnO would be gradually dissolved under the severely alkaline environment and subsequently incorporated into the ZSM-11 framework in the crystallization process. This facile new synthesis strategy can also be extended to prepare other Zn containing zeolites and is potentially important for practical utilization.

1. Introducción En los últimos años la protección ambiental y el uso de fuentes de energía renova... more 1. Introducción En los últimos años la protección ambiental y el uso de fuentes de energía renovables son dos objetivos principales en la investigación química. La energía solar se puede aprovechar para la degradación fotocatalítica de moléculas orgánicas contaminantes, hormonas o medicamentos, tanto en el aire, en el agua, como en las superficies, porque la luz solar es capaz de descomponerlas [1]. A pesar de la gran cantidad de aplicaciones fotocatalíticas de la titania (TiO2), fotocatalizador no tóxico, de bajo costo y muy prometedor [2], hay algunos factores críticos que limitan su fotoactividad. El principal es el valor de su salto de energía, que limita su uso como fotocatalizador en la región UV del espectro. Con el objetivo principal de extender su uso a la región visible del espectro, en literatura se ha propuesto el depósito de metales nobles en su superficie, modificaciones superficiales, así como el dopaje con iones de metales de transición o elementos de tierras raras. ...