20 results on '"Lo Presti, Francesca"'
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2. Molecular layer deposition to grow a luminescent metalorganic monolayer on inorganic substrate: Breaking monopoly of solution routes to self-assembled monolayer
- Author
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Pellegrino, Anna L., Tudisco, Cristina, Lo Presti, Francesca, Milan, Emil, Speghini, Adolfo, Condorelli, Guglielmo G., and Malandrino, Graziella
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- 2023
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3. An innovative strategic route to the green synthesis of CsPbBr3 films on rigid and flexible substrates
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Sirna, Lorenzo, Pellegrino, Anna L., Lo Presti, Francesca, Faini, Fabiola, Grancini, Giulia, Bengasi, Giuseppe, Foti, Marina, and Malandrino, Graziella
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- 2023
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4. A molecular route to fluoro-perovskite materials: synthesis of CsCaF3 films through a sol–gel/spin-coating process
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Pellegrino, Anna L., Lo Presti, Francesca, and Malandrino, Graziella
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- 2022
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5. Morphology controlled synthesis of yttrium metal–organic frameworks with a tritopic ligand
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Lo Presti, Francesca, Borzì, Aurelio, Pellegrino, Anna Lucia, Rossi, Patrizia, Paoli, Paola, and Malandrino, Graziella
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- 2022
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6. Stimuli-Responsive Properties of a Zinc(II) Salen-Type Schiff-Base Complex and Vapochromic Detection of Volatile Organic Compounds.
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Gaeta, Massimiliano, Oliveri, Ivan Pietro, Munzi, Gabriella, Lo Presti, Francesca, and Di Bella, Santo
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- 2024
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7. LiNbO 3 Thin Films through a Sol–Gel/Spin-Coating Approach Using a Novel Heterobimetallic Lithium–Niobium Precursor.
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Lo Presti, Francesca, Pellegrino, Anna Lucia, Micard, Quentin, Condorelli, Guglielmo Guido, Margueron, Samuel, Bartasyte, Ausrine, and Malandrino, Graziella
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THIN films , *ENERGY dispersive X-ray spectroscopy , *ATTENUATED total reflectance , *LITHIUM niobate , *RAMAN spectroscopy , *X-ray photoelectron spectroscopy - Abstract
Lithium niobate is a lead-free material which has attracted considerable attention due to its excellent optical, piezoelectric, and ferroelectric properties. This research is devoted to the synthesis through an innovative sol–gel/spin-coating approach of polycrystalline LiNbO3 films on Si substrates. A novel single-source hetero-bimetallic precursor containing lithium and niobium was synthesized and applied to the sol–gel synthesis. The structural, compositional, and thermal characteristics of the precursor have been tested through attenuated total reflection, X-ray photoelectron spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The LiNbO3 films have been characterized from a structural point of view with combined X-ray diffraction and Raman spectroscopy. Field-emission scanning electron microscopy, energy dispersive X-ray analysis, and X-ray photoelectron spectroscopy have been used to study the morphological and compositional properties of the deposited films. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Efficient Optimization of High‐Quality Epitaxial Lithium Niobate Thin Films by Chemical Beam Vapor Deposition: Impact of Cationic Stoichiometry.
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Pellegrino, Anna L., Wagner, Estelle, Lo Presti, Francesca, Maudez, William, Kolb, Simon, Rani, Rashmi, Bernard, Antoine, Guy, Stephan, Gassenq, Alban, Raevskaia, Marina, Grillet, Christian, Moalla, Rahma, Botella, Claude, Bachelet, Romain, Masenelli, Bruno, Bluet, Jean‐Marie, Cueff, Sebastien, Chapon, Patrick, Benvenuti, Giacomo, and Malandrino, Graziella
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CHEMICAL vapor deposition ,THIN films ,THIN film deposition ,STOICHIOMETRY ,LITHIUM niobate ,SAPPHIRES ,BAND gaps - Abstract
Lithium niobate is a material of special interest for its challenging functional properties, which can suit various applications. However, high quality 200‐mm LixNb1‐xO3 thin film grown on sapphire substrate have never been reported so far which limits these potential applications. This paper reports the efficient optimization of high quality LiNbO3 thin film deposition on sapphire (001) substrate through chemical beam vapor deposition in a combinatorial configuration. With this technique, flow ratio of Li/Nb can be tuned from ≈0.25 to ≈2.45 on a single wafer. Various complementary characterizations (by means of diffraction, microscopy and spectroscopy techniques) have been performed at different areas of the film (different cationic ratios) in order to investigate the impact of the cationic stoichiometry deviation on the film properties. Close to cationic stoichiometry (LiNbO3), the epitaxial films are of high quality (single phase in spite of two in‐plane domains, low mosaicity of 0.04°, low surface roughness, refractive index and band gap close to bulk values). Deviating from the stoichiometry conditions, secondary phases are detected (LiNb3O8 for Nb‐rich flow ratios, and Li3NbO4 with partial amorphization for Li‐rich flow ratios). LiNbO3 films are of high interest for various key applications in data communications among others. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Eu3+ activated BaF2 nanostructured thin films: fabrication and a combined experimental and computational study of the energy conversion process.
- Author
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Lo Presti, Francesca, Pellegrino, Anna Lucia, Milan, Emil, Radicchi, Eros, Speghini, Adolfo, and Malandrino, Graziella
- Abstract
Significant work has recently focused on developing novel materials suitable for solar technologies with better conversion efficiencies, while maintaining low costs. BaF
2 has been investigated as a fluoride host for doping with luminescent ions for energy conversion processes in photovoltaic cells. This work employed a metal–organic chemical vapor deposition technique to prepare nanostructured europium-doped BaF2 thin films on silicon and quartz substrates. Samples have been fabricated by varying the deposition temperature from 300 to 600 °C in order to examine how temperature affects the structure, morphology, and luminescence of Eu-doped BaF2 thin films. A multicomponent combination of fluorinated β-diketonate metal–organic precursors of barium and europium, Ba(hfa)2 ·tetraglyme and Eu(hfa)3 ·diglyme, in an appropriate molar ratio, is employed to fabricate BaF2 based thin films. These precursors serve as a single molten source by delivering all the elements required (Ba, Eu, and F) for forming the Eu-doped BaF2 phase due to the similar nature of the ligands. On silicon substrates, preliminary deposition tests have been carried out to confirm the purity, homogeneity, and appropriate stoichiometry of films. The obtained results pave the way for the production of BaF2 thin films doped with lanthanide ions, particularly interesting for their up-conversion (UC), down-conversion (DC), and down-shifting (DS) properties. [ABSTRACT FROM AUTHOR]- Published
- 2023
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10. Self-assembled BiFeO3@MIL-101 nanocomposite for antimicrobial applications under natural sunlight.
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Pulvirenti, Luca, Lombardo, Cinzia, Salmeri, Mario, Bongiorno, Corrado, Mannino, Giovanni, Lo Presti, Francesca, Cambria, Maria Teresa, and Condorelli, Guglielmo Guido
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HYBRID materials ,MATERIALS testing ,MULTIFERROIC materials ,X-ray photoelectron spectroscopy ,NANOCOMPOSITE materials ,MATRIX-assisted laser desorption-ionization - Abstract
In this paper, we report on the synthesis of a new hybrid photocatalytic material activated by natural sunlight irradiation. The material consists of multiferroic nanoparticles of bismuth ferrite (BFO) modified through the growth of the Fe-based MIL-101 framework. Material characterization, conducted using various techniques (X-ray diffraction, transmission electron microscopy, FTIR, and X-ray photoelectron spectroscopies), confirmed the growth of the MIL-101 metal–organic framework on the BFO surface. The obtained system possesses the intrinsic photo-degradative properties of BFO nanoparticles significantly enhanced by the presence of MIL-101. The photocatalytic activity of this material was tested in antibacterial experiments conducted under natural sunlight exposure within the nanocomposite concentration range of 100–0.20 µg/ml. The MIL-modified BFO showed a significant decrease in both Minimum Inhibiting Concentration and Minimum Bactericide Concentration values compared to bare nanoparticles. This confirms the photo-activating effect of the MIL-101 modification. In particular, they show an increased antimicrobial activity against the tested Gram-positive species and the ability to begin to inhibit the growth of the four Escherichia coli strains, although at the maximum concentration tested. These results suggest that the new nanocomposite BiFeO
3 @MOF has been successfully developed and has proven to be an effective antibacterial agent against a wide range of microorganisms and a potential candidate in disinfection processes. [ABSTRACT FROM AUTHOR]- Published
- 2023
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11. Green Ultrasound-Assisted Synthesis of Rare-Earth-Based MOFs.
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Lo Presti, Francesca, Pellegrino, Anna L., Consoli, Nancy, and Malandrino, Graziella
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FIELD emission electron microscopy , *METAL-organic frameworks , *X-ray powder diffraction , *THERMOGRAVIMETRY , *TECHNOLOGICAL innovations , *RARE earth metals - Abstract
Rare-earth (RE)-based metal organic frameworks (MOFs) are quickly gaining popularity as flexible functional materials in a variety of technological fields. These MOFs are useful for more than just conventional uses like gas sensors and catalyst materials; in fact, they also show significant promise in emerging technologies including photovoltaics, optical, and biomedical applications. Using yttrium and europium as ionic host centres and dopants, respectively, and 1,3,5-benzenetricarboxylic acid (H3-BTC) as an organic linker, we describe a simple and green approach for the fabrication of RE-MOFs. Specifically, Y-BTCs and Eu-doped Y-BTCs MOFs have been synthesised in a single step using an eco-friendly method that makes use of ultrasound technology. To establish a correlation between the morphological and structural properties and reaction conditions, a range of distinct reaction periods has been employed for the synthetic processes. Detailed analyses of the synthesised samples through powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), and Fourier-transform infrared spectroscopy (FT-IR) have confirmed the phase formation. Furthermore, thermal analyses such as thermogravimetric analysis (TGA) have been employed to evaluate the thermal stability and structural modifications of the Y-BTC and Eu-doped Y-BTC samples. Finally, the luminescent properties of the synthesised samples doped with Eu3+ have been assessed, providing an evaluation of their characteristics. As a proof of concept, an Eu-doped Y-BTC sample has been applied for the sensing of nitrobenzene as a molecule test of nitro derivatives. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Highly Tunable MOCVD Process of Vanadium Dioxide Thin Films: Relationship between Structural/Morphological Features and Electrodynamic Properties.
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Pellegrino, Anna Lucia, Lo Presti, Francesca, Papari, Gian Paolo, Koral, Can, Andreone, Antonello, and Malandrino, Graziella
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METAL organic chemical vapor deposition , *THIN films , *VANADIUM dioxide , *TERAHERTZ spectroscopy , *SCANNING electron microscopy - Abstract
The monoclinic structures of vanadium dioxide are widely studied as appealing systems due to a plethora of functional properties in several technological fields. In particular, the possibility to obtain the VO2 material in the form of thin film with a high control of structure and morphology represents a key issue for their use in THz devices and sensors. Herein, a fine control of the crystal habit has been addressed through an in-depth study of the metal organic chemical vapor deposition (MOCVD) synthetic approach. The focus is devoted to the key operative parameters such as deposition temperature inside the reactor in order to stabilize the P21/c or the C2/m monoclinic VO2 structures. Furthermore, the compositional purity, the morphology and the thickness of the VO2 films have been assessed through energy dispersive X-ray (EDX) analyses and field-emission scanning electron microscopy (FE-SEM), respectively. THz time domain spectroscopy is used to validate at very high frequency the functional properties of the as-prepared VO2 films. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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13. Metalorganic Chemical Vapor Deposition Approach to the Synthesis of Perovskite BaCeO 3 and BaCe 0.8 Y 0.2 O 3 Thin Films.
- Author
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Pellegrino, Anna L., Lo Presti, Francesca, and Malandrino, Graziella
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CHEMICAL vapor deposition , *PEROVSKITE , *THIN films , *ENERGY conversion , *HYDROGEN storage - Abstract
In the present energetic scenario, the development of materials with high potentiality in the technological fields of energy conversion processes, production and storage of hydrogen, are of great interest in the scientific community. In particular, we report for the first time the fabrication of crystalline and homogeneous barium-cerate-based materials in the form of thin films on various substrates. Starting from the β-diketonate precursor sources Ce(hfa)3diglyme, Ba(hfa)2tetraglyme and Y(hfa)3diglyme (Hhfa = 1,1,1,5,5,5-hexafluoroacetylacetone; diglyme = bis(2-methoxyethyl)ether; tetraglyme = 2,5,8,11,14-pentaoxapentadecane), a metalorganic chemical vapor deposition (MOCVD) approach has been successfully applied to the fabrication of BaCeO3 and doped BaCe0.8Y0.2O3 systems in the form of thin films. Structural, morphological and compositional analyses allowed for an accurate determination of the properties of deposited layers. The present approach represents a simple, easily scalable, and industrially appealing process for the production of compact and homogeneous barium cerate thin films. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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14. A Low Temperature Growth of Cu 2 O Thin Films as Hole Transporting Material for Perovskite Solar Cells.
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Pellegrino, Anna L., Lo Presti, Francesca, Smecca, Emanuele, Valastro, Salvatore, Greco, Giuseppe, Di Franco, Salvatore, Roccaforte, Fabrizio, Alberti, Alessandra, and Malandrino, Graziella
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PEROVSKITE , *THIN films , *SOLAR cells , *COPPER oxide films , *PHOTOVOLTAIC power systems , *FIELD emission electron microscopy , *CHEMICAL vapor deposition - Abstract
Copper oxide thin films have been successfully synthesized through a metal–organic chemical vapor deposition (MOCVD) approach starting from the copper bis(2,2,6,6-tetramethyl-3,5-heptanedionate), Cu(tmhd)2, complex. Operative conditions of fabrication strongly affect both the composition and morphologies of the copper oxide thin films. The deposition temperature has been accurately monitored in order to stabilize and to produce, selectively and reproducibly, the two phases of cuprite Cu2O and/or tenorite CuO. The present approach has the advantages of being industrially appealing, reliable, and fast for the production of thin films over large areas with fine control of both composition and surface uniformity. Moreover, the methylammonium lead iodide (MAPI) active layer has been successfully deposited on the ITO/Cu2O substrate by the Low Vacuum Proximity Space Effusion (LV-PSE) technique. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and atomic force microscopy (AFM) analyses have been used to characterize the deposited films. The optical band gap (Eg), ranging from 1.99 to 2.41 eV, has been determined through UV-vis analysis, while the electrical measurements allowed to establish the p-type conductivity behavior of the deposited Cu2O thin films with resistivities from 31 to 83 Ω cm and carrier concentration in the order of 1.5–2.8 × 1016 cm−3. These results pave the way for potential applications of the present system as a hole transporting layer combined with a perovskite active layer in emergent solar cell technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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15. Metal‐Organic Chemical Vapor Deposition of Oxide Perovskite Films: A Facile Route to Complex Functional Systems.
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Lo Presti, Francesca, Pellegrino, Anna L., and Malandrino, Graziella
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CHEMICAL vapor deposition ,METAL organic chemical vapor deposition ,THIN films ,OXIDE coating ,SYSTEMS availability ,PEROVSKITE - Abstract
Perovskite oxide type materials exhibit a great profusion of unique functional properties and for this reason they have been named inorganic chameleon. Nevertheless, their actual applications require the availability of these systems in thin‐film form synthesized through a simple, scalable, and straightforward technique. Metal‐organic chemical vapor deposition (MOCVD) has been shown to be an outstanding process to prepare thin films of multi‐component oxides. Herein, the focus is devoted to oxide perovskite thin films on both single crystal and non‐single crystal substrates through MOCVD processes. This study discusses the principles and the basic rules governing conventional, plasma‐enhanced, and liquid‐assisted MOCVD processes. Among a plethora of oxide perovskites, several classes of functionalities belonging to the perovskite class: from superconductors to dielectrics and giant‐k dielectrics, from colossal magnetoresistance to ionic conductors, piezoelectrics and ferroelectrics, are explored in detail. [ABSTRACT FROM AUTHOR]
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- 2022
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16. Synthesis of MIL-Modified Fe 3 O 4 Magnetic Nanoparticles for Enhancing Uptake and Efficiency of Temozolomide in Glioblastoma Treatment.
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Pulvirenti, Luca, Monforte, Francesca, Lo Presti, Francesca, Li Volti, Giovanni, Carota, Giuseppe, Sinatra, Fulvia, Bongiorno, Corrado, Mannino, Giovanni, Cambria, Maria Teresa, and Condorelli, Guglielmo Guido
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IRON oxide nanoparticles ,MAGNETIC nanoparticle hyperthermia ,MAGNETIC nanoparticles ,TEMOZOLOMIDE ,METHYLGUANINE ,X-ray photoelectron spectroscopy ,BRAIN tumors - Abstract
A nanometric hybrid system consisting of a Fe
3 O4 magnetic nanoparticles modified through the growth of Fe-based Metal-organic frameworks of the MIL (Materials Institute Lavoiser) was developed. The obtained system retains both the nanometer dimensions and the magnetic properties of the Fe3 O4 nanoparticles and possesses increased the loading capability due to the highly porous Fe-MIL. It was tested to load, carry and release temozolomide (TMZ) for the treatment of glioblastoma multiforme one of the most aggressive and deadly human cancers. The chemical characterization of the hybrid system was performed through various complementary techniques: X-ray-diffraction, thermogravimetric analysis, FT-IR and X-ray photoelectron spectroscopies. The nanomaterial showed low toxicity and an increased adsorption capacity compared to bare Fe3 O4 magnetic nanoparticles (MNPs). It can load about 12 mg/g of TMZ and carry the drug into A172 cells without degradation. Our experimental data confirm that, after 48 h of treatment, the TMZ-loaded hybrid nanoparticles (15 and 20 μg/mL) suppressed human glioblastoma cell viability much more effectively than the free drug. Finally, we found that the internalization of the MIL-modified system is more evident than bare MNPs at all the used concentrations both in the cytoplasm and in the nucleus suggesting that it can be capable of overcoming the blood-brain barrier and targeting brain tumors. In conclusion, these results indicate that this combined nanoparticle represents a highly promising drug delivery system for TMZ targeting into cancer cells. [ABSTRACT FROM AUTHOR]- Published
- 2022
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17. VOCs Photothermo-Catalytic Removal on MnO x -ZrO 2 Catalysts.
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Fiorenza, Roberto, Farina, Roberta Agata, Malannata, Enrica Maria, Lo Presti, Francesca, and Balsamo, Stefano Andrea
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TOLUENE ,VOLATILE organic compounds ,CATALYSTS ,IONIC interactions ,OPTICAL materials ,ZIRCONIUM oxide - Abstract
Solar photothermo-catalysis is a fascinating multi-catalytic approach for volatile organic compounds (VOCs) removal. In this work, we have explored the performance and the chemico-physical features of non-critical, noble, metal-free MnO
x -ZrO2 mixed oxides. The structural, morphological, and optical characterizations of these materials pointed to as a low amount of ZrO2 favoured a good interaction and the ionic exchange between the Mn and the Zr ions. This favoured the redox properties of MnOx increasing the mobility of its oxygens that can participate in the VOCs oxidation through a Mars-van Krevelen mechanism. The further application of solar irradiation sped up the oxidation reactions promoting the VOCs total oxidation to CO2 . The MnOx -5 wt.%ZrO2 sample showed, in the photothermo-catalytic tests, a toluene T90 (temperature of 90% of conversion) of 180 °C and an ethanol T90 conversion to CO2 of 156 °C, 36 °C, and 205 °C lower compared to the thermocatalytic tests, respectively. Finally, the same sample exhibited 84% toluene conversion and the best selectivity to CO2 in the ethanol removal after 5 h of solar irradiation at room temperature, a photoactivity similar to the most employed TiO2 -based materials. The as-synthetized mixed oxide is promising for an improved sustainability in both catalyst design and environmental applications. [ABSTRACT FROM AUTHOR]- Published
- 2022
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18. One-Pot Synthesis of TiO 2 -rGO Photocatalysts for the Degradation of Groundwater Pollutants.
- Author
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Balsamo, Stefano Andrea, Fiorenza, Roberto, Condorelli, Marcello, Pecoraro, Roberta, Brundo, Maria Violetta, Lo Presti, Francesca, and Sciré, Salvatore
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TITANIUM dioxide ,PHOTOCATALYSTS ,POLLUTANTS ,GRAPHENE oxide ,CATALYST testing ,HERBICIDES - Abstract
A non-conventional approach to prepare titanium dioxide-reduced graphene oxide (TiO
2 -rGO) nanocomposites based on solar photoreduction is here presented. The standard hydro-solvothermal synthesis of the TiO2 -rGO composites requires high temperatures and several steps, whereas the proposed one-pot preparation allows one to obtain the photocatalysts with a simple and green procedure, by exploiting the photocatalytic properties of titania activated by the solar irradiation. The TiO2 -rGO catalysts were tested in the solar photodegradation of a widely adopted toxic herbicide (2,4-Dichlorophenoxyacetic acid, 2,4-D), obtaining the 97% of degradation after 3 h of irradiation. The as-prepared TiO2 -rGO composites were more active compared to the same photocatalysts prepared through the conventional thermal route. The structural, optical, and textural properties of the composites, determined by Raman, Photoluminescence, Fourier Transform InfraRed (FTIR), UV-vis diffuse reflectance (DRS) spectroscopies, and N2 absorption-desorption measurements, showed as the solar irradiation favors the reduction of graphene oxide with higher efficiency compared to the thermal-driven synthesis. Furthermore, the possible toxicity of the as-synthesized composites was measured exposing nauplii of microcrustacean Artemia sp. to solutions containing TiO2 -rGO. The good results in the 2,4-D degradation process and the easiness of the TiO2 -rGO synthesis allow to consider the proposed approach a promising strategy to obtain performing photocatalysts. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
19. Self‐Assembling of Block Copolymers with Alternative Solvents.
- Author
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Lombardo, Valentina, D'Urso, Luisa, Lo Presti, Francesca, Scalese, Silvia, Magna, Antonino, and Puglisi, Rosaria A.
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BLOCK copolymers ,POLYMER solutions ,SOLVENTS ,ETHYL acetate ,CAUSATION (Philosophy) ,ENVIRONMENTAL risk - Abstract
Block copolymer (BCP) lithography is one of the most technologically intriguing and scientifically interesting strategies for achieving nanometer‐sized features. This method usually exploits toluene as solvent for the deposition of BCPs in all the processing steps. However, this chemical has some technical disadvantages, such as high toxicity and hygroscopicity. The first aspect can limit its use on the industrial scale because of the protocols on the environmental and operator risks, while the second causes aging effects that can alter the results. In order to overcome these intrinsic limitations, a BCP self‐assembly (BCP‐SA) strategy is presented by using alternative deposition solvents in place of toluene. A preliminary study, based on the physical characteristics, such as volatility, polarity, and hygroscopicity, is carried out to explore two new alternative solvents, ethyl acetate and tetrahydrofuran. The effects on the BCP‐SA due to the new solvents are studied by SEM analysis supported by suitable software for the images elaboration. The results achieved show very promising outcomes for the polymer solutions obtained with ethyl acetate, in terms of uniformity of geometrical features, ordered areas extension, and homogeneity of the pattern obtained, making this chemical a good alternative to toluene. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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20. Journey of a molecule from the solid to the gas phase and vice versa : direct estimation of vapor pressure of alkaline-earth metalorganic precursors for atmospheric pressure vapor phase deposition of fluoride films.
- Author
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Lo Presti F, Pellegrino AL, and Malandrino G
- Abstract
Atmospheric pressure (AP) vapor phase processes such as spatial atomic layer deposition (S-ALD) and AP-metalorganic chemical vapor deposition (AP-MOCVD) are becoming increasingly appealing for their use in a variety of academic and industrial applications. Evaluation of precursor vapour pressures is crucial for their application in AP processes and to this aim the Langmuir equation has been applied as a simple and straightforward method for estimating the vapor pressure and vaporization enthalpy of various metalorganic precursors. Using benzoic acid as a calibration reference, the vapour pressure-temperature curves for several alkaline-earth β-diketonate fluorinated compounds, with molecular formula "M(hfa)
2 ·L" (with M = Mg, Ca, Sr, Ba; Hhfa = 1,1,1,5,5,5-hexafluoroacetylacetone and L = diglyme, triglyme, and tetraglyme) are derived from their termogravimetric curves. Thus, the enthalpy of vaporization of all complexes has been estimated using the Clausius-Clapeyron equation. As a proof of concept, preliminary results on the use of [Mg(hfa)2 ·2H2 O]·2diglyme and [Ca(hfa)2 ·diglyme·H2 O] or [Ca(hfa)2 ·triglyme] as precursors for AP-MOCVD deposition of MgF2 and CaF2 in the form of thin films are presented. This approach may be used to easily determine vapor pressures of complexes and thus evaluate " a priori " the suitability of a compound as precursor for AP-MOCVD and/or spatial ALD.- Published
- 2022
- Full Text
- View/download PDF
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