2,889 research outputs found
Giornate europee del Patrimonio: Presentazione di libri al Castello di Torrechiara (PR)
No full textIn occasione della Giornata Europea del Patrimonio, è stata organizzata la presentazione dei volumi "La tradizione smarrita" di F. Benozzo (Viella, 2007) e "Le ombre della preistoria" di P. Galloni (Edizioni dell'Orso, 2007), coin il patrocinio del COmune di Langhirano e della Regione Emilia Romagn
Floating Photocatalysts as a Sustainable Solution for Water Harvesting in Vulnerable Communities
Get PDFThe exponential growth of the global population, projected to exceed 9 billion people by 2050, combined with increasing water scarcity driven by climate change, is placing unprecedented pressure on the world's water resources [1]. This issue is even more pronounced in developing countries, where water scarcity is a key factor behind numerous public health crises, during which unsanitary conditions expose both patients and doctors to risks of disease transmission [2].
In this challenging scenario, treating the tons of wastewater generated every day offers a promising solution. By transforming wastewater into a viable alternative water source, this approach addresses both resource scarcity and environmental sustainability. Although various technologies have been developed for water depollution (e.g., filtration, chemical or biological treatments) [3], they generally fail to remove contaminants of emerging concern (CECs) due to their high chemical stability, so developing efficient technologies for wastewater purification is crucial to mitigating water scarcity and ensuring access to safe water for all. In this framework, photocatalysis plays a pivotal role; indeed, the use of sunlight, an extremely powerful and abundant energy source, represents a vital resource in light of the current energy crisis. However, developing photocatalytic materials capable of exploiting the entire solar spectrum for pollutant photodegradation is challenging. Additionally, the most advanced materials reported in the literature are typically used as dispersed powders. Even if working with fine powders offers several benefits (e.g., high dispersion and impressive photoactivity), it also presents critical challenges, such as the difficulty of recovering them from the reaction mixture, which leads to contamination issues and additional costs [4]. For this reason, immobilizing photocatalysts strikes a balance between their advantages and the need for practical application by enhancing stability and enabling easier handling. In this context, floating photocatalysts offer the advantage of maximizing both light utilization and surface aeration, as they can remain at the air-water interface. Their use also reduces post-treatment costs. These foundations inspired the development of the project “Water Decontamination by Sunlight-Driven Floating Photocatalytic Systems” (SUNFLOAT). Within the SUNFLOAT project, various safe, cost-effective, and highly efficient photocatalysts designed to operate under solar irradiation were successfully fabricated and immobilized on different synthetic and natural floating supports [5-6]. The resulting materials were rigorously tested for the photodegradation of various CECs under both simulated and real sunlight conditions. The innovation introduced by the SUNFLOAT project highlights the practical viability of floating photocatalysts under natural solar conditions. The project underscores the effectiveness of these novel materials in harnessing solar energy for sustainable water purification. By proving their functionality under real sunlight, this initiative represents a significant advancement, offering an eco-friendly and scalable solution to improve water quality for remote communities facing water scarcity.
References:
[1]: He, C., Liu, Z., Wu, J., Pan, X., Fang, Z., Li, J., Brett, A.B., Nat. Commun.12, 4667 (2021).
[2]: https://www.cdc.gov
[3] Galloni, M.G., Ferrara, E., Falletta, E., Bianchi, C.L., Catalyst 12(8), 923, (2022).
[4] Djellabi, R., Giannantonio, R., Falletta, E., Bianchi, C.L., Curr. Opin. Chem. Eng.33, 100696 (2021).
[5] Galloni, M.G., Falletta, E., Mahdi, M., Giordana, A., Cerrato, G., Boffito, D.C., Bianchi, C.L., Adv. Sus. Syst. 2300565 (2024).
[6] Galloni, M.G., Nikonova, V., Cerrato, G., Giordana, A., Pleva, P., Humpolicek, P., Falletta, E., Bianchi, C.L., J. Environ. Man., 369, 122365, (2024)
Construction of electron-active complex systems as model for artificial photosynthesis
No full textLa fotosintesi artificiale è un obiettivo ambizioso per la scienza moderna, che richiede una comprensione completa dei sistemi naturali. La comprensione di tutte le diverse reazioni del sistema è uno degli aspetti fondamentali nella ricerca chimica, fisica e biologica. Lo studio delle reazioni di trasferimento elettronico tra un accettore e un donatore è un punto cruciale, sia per lo sviluppo di sistemi artificiali sintetici, sia per possibili applicazioni nella costruzione di dispositivi elettronici e materiali fotosensibili. Lo scopo di questa tesi è stato quello di investigare reazioni di trasferimento elettronico e di energia, per avere informazioni riguardo le leggi che regolano questi sistemi complessi, usando diversi sistemi donatore-accettore, tra i quali particolare attenzione è stata rivolta al C60 come accettore e al ferrocene come donatore. Il lavoro sintetico è stato una parte importante della tesi, richiedendo tempo per ottimizzare le condizioni di reazione, le procedure di purificazione e per la completa caratterizzazione dei prodotti. Numerosi nuovi composti sono stati sintetizzati e sono state migliorate le rese per alcuni prodotti noti da letteratura. Un aspetto importante del lavoro ha riguardato lo studio dell’interazione tra donatore e l’accettore in alcune delle diadi ottenute, sia allo stato fondamentale, sia nello stato eccitato. Tra i vari risultati, i più interssanti possono essere riassunti nei seguenti punti. a) Un andamento peculiare emerge dagli esperimenti fotofisici e computazionali e dalle misure elettrochimiche e degli spettri di assorbimento nelle diadi fluorene-fullerene: cambia l’interazione, cambiando la posizione del fluorene che lega il fullerene. b) Risultati molto interessanti sono stati ottenuti quando ferrocene e fullerene sono uniti tramite legame spiro, dando una diade dalla geometria rigida. Difatti, confrontando le proprietà nello stato eccitato di questa diade con quelle della N-metil-2-ferrocenil-[3,4]-fulleropirrolidina, con maggiore libertà conformazionale, è stata osservata una reazione di trasferimento elettronico più veloce, indice di una maggiore interazione tra i due componenti. c) In diadi supramolecolari composte da ZnSalen e N-metil-2-piridil-[3,4]-fulleropirrolidina è stato osservato un efficiente trasferimento di energia. Questo sistema può essere usato come modello nei sistemi impiegati nella cattura della luce. d) Un efficiente trasferimento di elettroni avviene tra la tetraferrocenilporfirina di zinco e la N-metil-2piridil-[3,4]-fulleropirrolidina in una diade supramolecolare, come è stato osservato tramite la spettroscopia transiente, dove un tempo di vita di 800 ps della specie eccitata a separazione di carica è stato ottenuto in un solvente apolare come il toluene. In conclusione, sono stati ottenuti nuovi sistemi per lo studio delle reazioni di trasferimento di energia e di elettroni, che sono stati studiati usando diversi approcci sperimentali. I risultati possono essere di aiuto sia per una miglior comprensione dei fenomeni naturali, sia per lo sviluppo e la costruzione di dispositivi fotosensibili.Artificial photosynthesis is an ambitions target of modern science that obviously requires a complete understanding of natural photosynthesis. The understanding of all steps involved is one of the most important topic in chemical, biological, and physical research. The study of electron transfer reaction between donor and acceptor molecules is a crucial key point, both for development of artificial photosynthesis and for application in electronic devices and photosensible materials. The aim of this thesis was to investigate electron and energy transfer reactions, as source of information about the mechanisms that rule this complex reaction, using different donor-acceptor systems, among which attention have been focused at C60 as acceptor and ferrocene as donor. Synthetic work constituted a major task in this thesis, requiring several attempts in order to optimize reaction conditions, purification procedures and full characterization of products. A number of new compounds was obtained together with improved yields of known products. Another important aspect of the work involved investigation of donor-acceptor interaction in some of the dyads, both in ground and in excited states. Among all the results, the most significant ones may be summarized in the following points. a) A peculiar behaviour emerged from photophysical and computational experiments, electronic spectra and electrochemical measurements of fluorene-fullerene dyads. Different interaction was the result of changing the position through which the two moieties are connected. b) Very interesting results emerged when a frozen structure was obtained from connecting ferrocene and fullerene moieties in a rigid assembly. In fact, in comparison with a dyad with flexible connection, a faster electron transfer rate - and therefore an enhanced interaction - was observed in the excited state. c) Efficient energy transfer was observed with supramolecular (ZnSalen)-(N-methyl-2-pyridyl-[3,4]fulleropyrrolidine) dyads. This system can be used as a good model for light harvesting model. d) Very efficient electron transfer reaction occurred between zinctetraferrocenylporphyrin and pyridylfulleropyrrolidine in supramolecular (ZnFc4Porph)-(N-methyl-2-pyridyl-[3,4]-fulleropyrrolidine) dyad, as observed by transient spectroscopy, even in non polar solvent such as toluene. In conclusion, new good systems for energy an electron transfer were obtained and investigated by different approaches. They can be used to reach a deeper knowledge of complex phenomena that rule natural photosynthesis as well as to build photosensible devices
Solar-powered solutions: floating photocatalysts for sustainable water purification in a resource-challenged world
No full textThe exponential growth of the global population, projected to exceed 9 billion people by 2050, combined with increasing water scarcity driven by climate change, is placing unprecedented pressure on the world's water resources [1]. This issue is even more pronounced in developing countries, where water scarcity is a key factor behind numerous public health crises, during which unsanitary conditions expose both patients and doctors to risks of disease transmission [2].
In this challenging scenario, treating the tons of wastewater generated every day offers a promising solution. By transforming wastewater into a viable alternative water source, this approach addresses both resource scarcity and environmental sustainability. Although various technologies have been developed for water depollution (e.g., filtration, chemical or biological treatments) [3], they generally fail to remove contaminants of emerging concern (CECs) due to their high chemical stability, so developing efficient technologies for wastewater purification is crucial to mitigating water scarcity and ensuring access to safe water for all. In this framework, photocatalysis plays a pivotal role; indeed, the use of sunlight, an extremely powerful and abundant energy source, represents a vital resource in light of the current energy crisis. However, developing photocatalytic materials capable of exploiting the entire solar spectrum for pollutant photodegradation is challenging. Additionally, the most advanced materials reported in the literature are typically used as dispersed powders. Even if working with fine powders offers several benefits (e.g., high dispersion and impressive photoactivity), it also presents critical challenges, such as the difficulty of recovering them from the reaction mixture, which leads to contamination issues and additional costs [4]. For this reason, immobilizing photocatalysts strikes a balance between their advantages and the need for practical application by enhancing stability and enabling easier handling. In this context, floating photocatalysts offer the advantage of maximizing both light utilization and surface aeration, as they can remain at the air-water interface. Their use also reduces post-treatment costs. These foundations inspired the development of the project “Water Decontamination by Sunlight-Driven Floating Photocatalytic Systems” (SUNFLOAT). Within the SUNFLOAT project, various safe, cost-effective, and highly efficient photocatalysts designed to operate under solar irradiation were successfully fabricated and immobilized on different synthetic and natural floating supports [5-6]. The resulting materials were rigorously tested for the photodegradation of various CECs under both simulated and real sunlight conditions. The innovation introduced by the SUNFLOAT project highlights the practical viability of floating photocatalysts under natural solar conditions. The project underscores the effectiveness of these novel materials in harnessing solar energy for sustainable water purification. By proving their functionality under real sunlight, this initiative represents a significant advancement, offering an eco-friendly and scalable solution to improve water quality for remote ommunities facing water scarcity.
References:
[1]: He, C., Liu, Z., Wu, J., Pan, X., Fang, Z., Li, J., Brett, A.B., Nat. Commun.12, 4667 (2021).
[2]: https://www.cdc.gov
[3]: Galloni, M.G., Ferrara, E., Falletta, E., Bianchi, C.L., Catalyst 12(8), 923, (2022)
[4]: Djellabi, R., Giannantonio, R., Falletta, E., Bianchi, C.L., Curr. Opin. Chem. Eng.33, 100696 (2021)
[5]: Galloni, M.G., Falletta, E., Mahdi, M., Giordana, A., Cerrato, G., Boffito, D.C., Bianchi, C.L., Adv. Sus. Syst. 2300565 (2024),
[6] Galloni, M.G., Nikonova, V., Cerrato, G., Giordana, A., Pleva, P., Humpolicek, P., Falletta, E., Bianchi, C.L., J. Environ. Man., 369, 122365, (2024
Matteo Galloni, Cultura, evangelizzazione e fede nel «Protrettico» di Clemente Alessandrino (coll. Verba seniorum, N.S., 10). 1986
No full textDe Halleux André. Matteo Galloni, Cultura, evangelizzazione e fede nel «Protrettico» di Clemente Alessandrino (coll. Verba seniorum, N.S., 10). 1986. In: Revue théologique de Louvain, 18ᵉ année, fasc. 2, 1987. p. 248
Synthesis of new ferrocenyl derivatives and their use in the first cyclopropanation of fullerene C-60 with ferrocenes
No full textNew ferrocenyl derivatives (a beta-ketoester and a beta-diester) were synthesised and linked to fullerene C-60, with the aim to elucidate factors involved in intramolecular electronic communication. These are the first examples of fullerene functionalised with ferrocenes via the cyclopropanation reaction. The resulting dyads were characterised. (C) 2003 Elsevier B.V. All rights reserved
KuQuinones as sensitizers of NiO based p-type dye-sensitized solar cells
Get PDFA new series of KuQuinones (KuQs) have been synthesized and employed as dye-sensitizers for NiO-based p-type dye-sensitized solar cells (p-DSSCs). KuQs are pentacyclic quinoid compounds which are characterized by a fully conjugated structure that is responsible for the strong and broad absorption in the visible spectrum. The HOMO/LUMO states of KuQs considered here have matching energy levels with the upper edge of the NiO valence band and I−/I3 − redox potential energy. These features render such compounds suitable for NiO sensitization in p-DSSCs. The new carboxylic acid-substituted KuQ derivatives proposed here differ in the length of the alkyl chain. The JV characteristic curves and the external quantum efficiency spectra have been recorded. The results showed that the performances of KuQ-sensitized cells were similar to that of the benchmark sensitizer erythrosine B (Ery B), despite the lack of electronic conjugation between the anchoring group and the light absorbing unit. This result led us to hypothesize that the photoinduced charge transfer between the excited KuQ dyes and the NiO electrode occurred through space and not via chemical bonds as it usually occurs in these systems. The mechanism of charge transfer through space has been supported by data from IR spectroscopy. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique
Bromination of tetrapyrrolic scaffolds: a sustainable approach
No full textA sustainable procedure developed for the bromination of organic substrates, such as olefins and small aromatic rings, has been applied to porphyrin derivatives. The synthetic method, based on a V(V) or Mo(VI) catalyzed reaction, occurs in a two-phase medium and uses cheap and environmental friendly reagents such as KBr and H2O2 as the bromine source and primary oxidant respectively. Compared to the classical protocols for porphyrinoid bromination, this approach is based on milder and safer reaction conditions. The selective formation of mono or polybrominated substrates has been achieved by accurate tuning of key parameters (H2O2 and KBr amount, catalyst). While with vanadium good results to obtain partially substituted porphyrins have been gained, full peripheral functionalization can be obtained with either vanadium or molybdenum catalysis depending on the metal ion coordinated to the inner cor
A journey into the electrochemistry of vanadium compounds
No full texttVanadium is an element with a fascinating history, a widespread diffusion in bacteria and eukaryan organ-isms, and rich coordination chemistry. The properties of vanadium compounds attracted the interest ofresearchers in different fields, such as biochemistry, medicinal chemistry, and catalysis, leading to severalreviews. However, although the rich and varied chemistry of vanadium was acknowledged to be due tothe variety of easily accessible oxidation states, no review was devoted – to the best of our knowledge – toelectrochemical properties of vanadium compounds. The present review aims at filling this lacuna, pre-senting a survey of electrochemical data related to vanadium compounds, starting from the eighties of thelast century until mid 2014. The data are organized in tables, with experimental information necessaryfor comparisons, according to oxidation states of vanadium, beginning with the largest set, that is thatof vanadium(IV) compounds and, within this set, on the basis of ligand coordinating atoms. The original ligands abbreviations were kept, when possible, or adapted, according to recent IUPAC recommenda-tions. We hope to offer the reader a comprehensive – if not complete – overview of electrochemistry ofvanadium compounds and to make relatively easy to retrieve the desired information. What is evidentis the variety and versatility of vanadium compounds also in redox processes
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