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3. A Perspective on Recent Advances in Phosphorene Functionalization and its Application in Devices

Author

Peruzzini, Maurizio, Bini, Roberto, Bolognesi, Margherita, Caporali, Maria, Ceppatelli, Matteo, Cicogna, Francesca, Coiai, Serena, Heun, Stefan, Ienco, Andrea, Benito, Inigo Iglesias, Kumar, Abhishek, Manca, Gabriele, Passaglia, Elisa, Scelta, Demetrio, Serrano-Ruiz, Manuel, Telesio, Francesca, Toffanin, Stefano, and Vanni, Matteo

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Chemical Physics
Abstract

Phosphorene, the 2D material derived from black phosphorus, has recently attracted a lot of interest for its properties, suitable for applications in material science. In particular, the physical features and the prominent chemical reactivity on its surface render this nanolayered substrate particularly promising for electrical and optoelectronic applications. In addition, being a new potential ligand for metals, it opens the way for a new role of the inorganic chemistry in the 2D world, with special reference to the field of catalysis. The aim of this review is to summarize the state of the art in this subject and to present our most recent results in preparation, functionalization and use of phosphorene and its decorated derivatives. In particular, we discuss several key points, which are currently under investigation: the synthesis, the characterization by theoretical calculations, the high pressure behaviour of black phosphorus, as well as decoration with nanoparticles and encapsulation in polymers. Finally, device fabrication and electrical transport measurements are overviewed on the basis of recent literature and new results collected in our laboratories.

Published
2019
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4. Polymer-based black phosphorus (bP) hybrid materials by in situ radical polymerization: an effective tool to exfoliate bP and stabilize bP nanoflakes

Author

Passaglia, Elisa, Cicogna, Francesca, Costantino, Federica, Coiai, Serena, Legnaioli, Stefano, Lorenzetti, Giulia, Borsacchi, Silvia, Geppi, Marco, Telesio, Francesca, Heun, Stefan, Ienco, Andrea, Serrano-Ruiz, Manuel, and Peruzzini, Maurizio

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science, Physics - Applied Physics, Physics - Chemical Physics
Abstract

Black phosphorus (bP) has been recently investigated for next generation nanoelectronic multifunctional devices. However, the intrinsic instability of exfoliated bP (the bP nanoflakes) towards both moisture and air has so far overshadowed its practical implementation. In order to contribute to fill this gap, we report here the preparation of new hybrid polymer-based materials where bP nanoflakes exhibit a significantly improved stability. The new materials have been prepared by different synthetic paths including: i) the mixing of conventionally liquid-phase exfoliated bP (in DMSO) with PMMA solution; ii) the direct exfoliation of bP in a polymeric solution; iii) the in situ radical polymerization after exfoliating bP in the liquid monomer (methyl methacrylate, MMA). This last methodology concerns the preparation of stable suspensions of bPn-MMA by sonication-assisted liquid phase exfoliation (LPE) of bP in the presence of MMA followed by radical polymerization. The hybrids characteristics have been compared in order to evaluate the bP dispersion and the effectiveness of the bPn interfacial interactions with polymer chains aimed at their long-term environmental stabilization. The passivation of bPn results particularly effective when the hybrid material is prepared by in situ polymerization. By using this synthetic methodology, the nanoflakes, even if with a gradient of dispersion (size of aggregates), preserve their chemical structure from oxidation (as proved by both Raman and 31P-Solid State NMR studies) and are particularly stable to air and UV light exposure.

Published
2018
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6. Incorporation of 2D black phosphorus (2D-bP) in P3HT/PMMA mixtures for novel materials with tuned spectroscopic, morphological and electric features

Author

Coiai, Serena, Cicogna, Francesca, Scittarelli, Doriana, Legnaioli, Stefano, Borsacchi, Silvia, Ienco, Andrea, Serrano-Ruiz, Manuel, Caporali, Maria, Peruzzini, Maurizio, Dinelli, Franco, Ishak, Randa, Signori, Francesca, Toffanin, Stefano, Bolognesi, Margherita, Prescimone, Federico, and Passaglia, Elisa

Published
2021
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30. Pd and Rh nanoparticles onto ion-exchange borate monoliths: synthesis, characterization and application to selective hdrogenation reactions under continuous flow

Author

Liguori, Francesca, Barbaro, Pierluigi, Coiai, Serena, and Passaglia, Elisa

Subjects
flow reactor, monoliths, nanoparticles, hydrogenation
Abstract

Strong cation-exchange resins featured by low loading of noncoordinating B(C6H5)3- anions in styrene-divinylbenzene matrices at various cross-linking degree were synthesized via free radical bulk copolymerization with appropriate borate monomers. The polymerization mixture was tailored to obtain swellable materials for use as insoluble carriers of single-site heterogeneous catalysts. Having established an effective protocol for the synthesis of this material, we prepared an unconventional monolith (called MonoBor) featuring an homogeneous microstructure of interconnected macropores (10 ?m size) in situ, into a commercial glass column, so as to provide a monolithic mesoreactor perfectly suited for use under continuous flow.1 Palladium and Rhodium nanoparticles were immobilized onto the monolith and the resulting Pd or Rh@MonoBor catalyst was employed in the semihydrogenation reaction of alkynes 2 and selective hydrogenation of unsatured carbonyl compounds 3 under continuous flow by direct connection to a home-made reactor system. The macroporous monolith, showing excellent hydrodynamic properties and high chemical and mechanical stability, was successfully used under mild reaction conditions, without additives, with high performance in terms of space-to-time yield productivity, selectivity and catalyst durability.

Published
2018

31. A Perspective on Recent Advances in Phosphorene Functionalization and Its Applications in Devices

Author

Peruzzini, Maurizio, primary, Bini, Roberto, additional, Bolognesi, Margherita, additional, Caporali, Maria, additional, Ceppatelli, Matteo, additional, Cicogna, Francesca, additional, Coiai, Serena, additional, Heun, Stefan, additional, Ienco, Andrea, additional, Benito, Iñigo Iglesias, additional, Kumar, Abhishek, additional, Manca, Gabriele, additional, Passaglia, Elisa, additional, Scelta, Demetrio, additional, Serrano‐Ruiz, Manuel, additional, Telesio, Francesca, additional, Toffanin, Stefano, additional, and Vanni, Matteo, additional

Published
2018
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35. Polymer-Based Black Phosphorus (bP) Hybrid Materials by in Situ Radical Polymerization: An Effective Tool To Exfoliate bP and Stabilize bP Nanoflakes

Author

Passaglia, Elisa, primary, Cicogna, Francesca, additional, Costantino, Federica, additional, Coiai, Serena, additional, Legnaioli, Stefano, additional, Lorenzetti, Giulia, additional, Borsacchi, Silvia, additional, Geppi, Marco, additional, Telesio, Francesca, additional, Heun, Stefan, additional, Ienco, Andrea, additional, Serrano-Ruiz, Manuel, additional, and Peruzzini, Maurizio, additional

Published
2018
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38. POLYMER SURFACE MODIFICATION BY PHOTO-GRAFTING OF FUNCTIONAL NITROXIDES

Author

CICOGNA Francesca 1, DOMENICHELLI Ilaria 2, COIAI Serena 1, PINZINO Calogero 1, TADDEI Sara 3, MARTINELLI Elisa 3, and PASSAGLIA Elisa 1

Subjects
functional nitroxide radical, photografting, surface modification
Abstract

The modification of polymer surfaces by UV-induced graft polymerization is a powerful method to change the surface characteristics of a polymer without altering its bulk features [1]. In this work an alternative approach to modify the surface properties of an ethylene-octene copolymer (EOC) and of a polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) block copolymer is described. X-TEMPO derivatives were used as functional species in place of unsaturated monomers. Indeed TEMPO radicals can react with macroradicals by coupling giving rise to the functionalization of polymers in a peroxide-initiated radical process [2, 3]. In an UV photo-grafting process, the excited photo-initiator gives rise to macroradicals by H-abstraction from the polymer chains, and the X-TEMPO derivatives react with the carbon-centered macroradicals by coupling leading to the surface functionalization of the polymer material (Fig. 1). The 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl (BzO-TEMPO), the 4-(1-naphthoate)-2,2,6,6-tetramethylpiperidine-1-oxyl (NfO-TEMPO) and the 4-(4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-nonanoate)-2,2,6,6-tetramethyl-piperidine-1-oxyl (Fluo-TEMPO) were used as functional X-TEMPO radicals, whereas the 4-methoxybenzophenone (MeOBP) was used as a photo-initiator. The resulting functionalized polymers were characterized by ATR-FTIR spectroscopy, Electron Paramagnetic Resonance (EPR) and thermogravimetric analysis (TGA). Data confirmed the grafting of X-TEMPO derivatives and allowed the evaluation of the amount of grafted species. The fluorescence emission spectroscopy was used to investigate the optical properties of the NfO-TEMPO functionalized samples, while the contact angle measurements highlighted the wettability of the polymer surface modified with Fluo-TEMPO. Results show that the properties of the free X-TEMPO derivatives were transferred to the polymer surface thus giving "functional" polymer films.

Published
2016

39. Poly(lactic acid) plasticized with low-molecular-weight polyesters: structural, thermal and biodegradability features

Author

Cicogna, Francesca, primary, Coiai, Serena, additional, De Monte, Cristina, additional, Spiniello, Roberto, additional, Fiori, Stefano, additional, Franceschi, Massimiliano, additional, Braca, Francesca, additional, Cinelli, Patrizia, additional, Fehri, Seyed Mohammad Kazem, additional, Lazzeri, Andrea, additional, Oberhauser, Werner, additional, and Passaglia, Elisa, additional

Published
2017
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40. Post‐polymerization modification by nitroxide radical coupling.

Author

Coiai, Serena, Passaglia, Elisa, and Cicogna, Francesca

Subjects
POLYMERIZATION, NITROXIDES, COUPLING reactions (Chemistry), PLASTICS, PIPERIDINE, AMINES
Abstract

Post‐polymerization modification is an attractive approach to extend applications and convert commodity plastics into products with new, desirable and tunable properties. Among the post‐polymerization modification methods, the nitroxide radical coupling (NRC) reaction has been shown to be a convenient and versatile way to graft specific functionalities onto polymer chains and to control the onset and yield of polymer crosslinking during peroxide‐initiated processes. The use of 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) and its derivatives as controllers of scorch in crosslinking and as functionalizers in functionalization reactions is thoroughly described. Examples are also given of graft polymerization from macroalkoxyamines generated by NRC and grafting of nitroxides by irradiation processes. In addition, in this review we attempt to demonstrate the broad applications of the NRC reaction in the preparation of polymers with a multitude of functionalities and elaborate architectures. The examples discussed here concern the use of atom transfer and single electron transfer NRC reactions to design a variety of polymers with asymmetrical structure and the use of the radical crossover reaction, based on the alkoxyamine dynamic covalent bond, to generate reversible polymer structures and switchable functional polymers. © 2018 Society of Chemical Industry The coupling reaction between nitroxides and carbon‐centered radicals, also known as nitroxide radical coupling, is presented as an attractive, convenient and versatile post‐polymerization modification method. [ABSTRACT FROM AUTHOR]

Published
2019
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41. Thermo-oxidative stabilization of poly(lactic acid) with antioxidant intercalated layered double hydroxides

Author

Pérez Amaro, Lucía, Cicogna, Francesca, Passaglia, Elisa, Morici, Elisabetta, Oberhauser, Werner, Al-Malaika, Sahar, Dintcheva, Nadka Tz, Coiai, Serena, Pérez Amaro, Lucía, Cicogna, Francesca, Passaglia, Elisa, Morici, Elisabetta, Oberhauser, Werner, Al-Malaika, Sahar, Dintcheva, Nadka Tz, and Coiai, Serena

Abstract

Two antioxidant modified layered double hydroxides (AO-LDHs) were successfully prepared by theintercalation of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid (IrganoxCOOH) and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) in the layered structure of LDH. It was foundthat by anchoring the phenolic moieties to the LDH layers the antioxidant power is retained in the caseof Trolox, and even amplified in the case of IrganoxCOOH. A small amount of the two AO-LDHs wasincorporated into poly(lactic acid), PLA, by solution mixing and melt extrusion. The thermo-oxidativestability of the composites was compared with that of the neat PLA and PLA containing free AOs. SECanalysis indicates that, after a controlled period of ageing, both the AO-LDHs protect the PLA fromchain scission. The oxidation induction time (OIT, DSC) at 230 °C shows also the beneficial effects ofthe presence of the functional filler in the polymer matrix. Further, results from a preliminary migrationtest suggest that the AO species have a low tendency to migrate away from the AO-LDHs embedded inthe polymer matrix thus keeping the AO protected inside the nanofiller layers thereby remaining activefor a longer time.

Published
2016

47. The effect of layered double hydroxides dispersion on thermal and mechanical properties of poly(vinyl chloride)/poly(methyl methacrylate) blends

Author

Amaro Perez, Lucia, Coiai, Serena, Conzatti, Lucia, Manariti, Antonella, Ciardelli, Francesco, and Passaglia, Elisa

Subjects
poly(vinyl chloride), poly(methyl methacrylate), layered double hydroxides, composites, thermal stability
Abstract

Poly(vinyl chloride) (PVC)/layered double hydroxide (LDH) composites and PVC/poly(methyl methacrylate) (PMMA)/LDH composites were prepared via solution intercalation into PVC using both unmodified and organo-modified LDHs and variable-molecular-weight PMMA as additional components. The LDH dispersion was investigated using X-ray diffraction analysis and electron microscopy in scanning and transmission modes. Spotlight fourier transform infrared (FTIR) chemical imaging analysis was also used to obtain a deeper insight into the dispersion of polymer phases and LDH segregation. Thermal properties were determined using thermogravimetric analysis and differential scanning calorimetry; moreover, a preliminary investigation of mechanical properties in tensile mode and evaluation of the Vicat softening temperature were carried out. The morphological analysis of PVC/LDH and PVC/PMMA/LDH composites evidenced in both cases the presence of disordered micro-aggregates with loss of the LDH crystallographic symmetry depending on the amount and molecular weight of PMMA. In particular, in the case of PVC/PMMA/LDH composites, the FTIR imaging analysis showed that PMMA mostly segregated in the LDH phase. However, even if the degree of LDH dispersion was not elevated (micro-aggregates with disordered structures and size ranging from 0.5 up to 11 mu m were evidenced), thermal stability and mechanical properties of the composites were improved with a synergic effect of PMMA and LDH. (c) 2013 Society of Chemical Industry

Published
2013

48. Reazioni su polimeri

Author

Coiai, Serena, Cicogna, Francesca, and Passaglia, Elisa

Published
2012

49. Grafting of Functional Nitroxyl Free Radicals to Polyolefins as a Tool to Postreactor Modification of Polyethylene-Based Materials with Control of Macromolecular Architecture

Author

Cicogna, Francesca, Coiai, Serena, Passaglia, Elisa, Tucci, Irene, Ricci, Lucia, Ciardelli, Francesco, and Batistini, Antonio

Abstract

Nitroxyl radicals were used as functionalizing agents during the free radical postreactor modification process of polyolefins carried out in the melt. The 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (HO-TEMPO) and the 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl (BzO-TEMPO) free radicals were successfully grafted onto a polyethylene-based material (ethylene-co-1-octene copolymer) by coupling reaction with polymer macroradicals; these last were formed by H-abstraction through peroxide addition. The macromolecular structure of the functionalized polyolefins was assessed by 1H-NMR, FTIR spectroscopy, and SEC measurements which were used to evidence the grafting site, to evaluate the grafting level and to highlight the occurrence of chain extension through crosslinking side reactions. Indeed the use of proper model compounds allowed the preparation of accurate FTIR calibration curves for the quantitative determination of the functionalization degree. Besides the high temperature SEC analysis highlighted that this fast and simple coupling reaction between macroradicals and nitroxyl free radicals grants the grafting of functionalities onto the polyolefin backbone by contemporarily preventing the side reactions liable of the structure and MW modification of the pristine polymer.

Published
2011

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