Search

Your search keyword '"Capasso, Andrea"' showing total 176 results
Start Over Author "Capasso, Andrea"
176 results on '"Capasso, Andrea"'

3. Rational Design of Photo-Electrochemical Hybrid Devices based on Graphene and Chlamydomonas reinhardtii Light-Harvesting Proteins

Author

Ortiz-Torres, Martha, Fernández-Niño, Miguel, Cruz, Juan C, Capasso, Andrea, Matteocci, Fabio, Patiño, Edgar J., Hernández, Yenny, and Barrios, Andrés Fernando González

Subjects
Physics - Chemical Physics
Abstract

Dye-sensitized solar cells (DSSCs) have been highlighted as the promising alternative to generate clean energy based on low pay-back time materials. These devices have been designed to mimic solar energy conversion processes from photosynthetic organisms (the most efficient energy transduction phenomenon observed in nature) with the aid of low-cost materials. Recently, light-harvesting complexes (LHC) have been proposed as potential dyes in DSSCs based on their higher light-absorption efficiencies as compared to synthetic dyes. In this work, photo-electrochemical hybrid devices were rationally designed by adding for the first time Leu and Lys tags to heterologously expressed light-harvesting proteins from Chlamydomonas reinhardtii, thus allowing their proper orientation and immobilization on graphene electrodes. The light-harvesting complex 4 from C. reinhardtii (LHC4) was initially expressed in Escherichia coli, purified via affinity chromatography and subsequently immobilized on plasma-treated thin-film graphene electrodes. A photocurrent density of 40.30 \pm 9.26 \mu A/cm2 was measured on devices using liquid electrolytes supplemented with a phosphonated viologen to facilitate charge transfer. Our results suggest that a new family of graphene-based thin-film photovoltaic devices can be manufactured from rationally tagged LHC proteins and opens the possibility to further explore fundamental processes of energy transfer for biological components interfaced with synthetic materials., Comment: 17 pages, 4 figures

Published
2020

4. CVD-graphene/graphene flakes dual-films as advanced DSSC counter electrodes

Author

Capasso, Andrea, Bellani, Sebastiano, Palma, Alessandro Lorenzo, Najafi1, Leyla, Castillo, Antonio Esaù Del Rio, Curreli1, Nicola, Cinà, Lucio, Miseikis, Vaidotas, Coletti, Camilla, Calogero, Giuseppe, Pellegrini, Vittorio, Di Carlo, Aldo, and Bonaccorso, Francesco

Subjects
Physics - Applied Physics, Condensed Matter - Materials Science
Abstract

The use of graphene-based electrodes is burgeoning in a wide range of applications, including solar cells, light emitting diodes, touch screens, field-effect transistors, photodetectors, sensors and energy storage systems. The success of such electrodes strongly depends on the implementation of effective production and processing methods for graphene. In this work, we take advantage of two different graphene production methods to design an advanced, conductive oxide- and platinum-free, graphene-based counter electrode for dye-sensitized solar cells (DSSCs). In particular, we exploit the combination of a graphene film, produced by chemical vapor deposition (CVD) (CVD-graphene), with few-layer graphene (FLG) flakes, produced by liquid phase exfoliation. The CVD-graphene is used as charge collector, while the FLG flakes, deposited atop by spray coating, act as catalyst for the reduction of the electrolyte redox couple (i.e., I3-/I-- and Co+2/+3). The as-produced counter electrodes are tested in both I3-/I-- and Co+2/+3-based semitransparent DSSCs, showing power conversion efficiencies of 2.1% and 5.09%, respectively, under 1 SUN illumination. At 0.1 SUN, Co+2/+3-based DSSCs achieve a power conversion efficiency as high as 6.87%. Our results demonstrate that the electrical, optical, chemical and catalytic properties of graphene-based dual films, designed by combining CVD-graphene and FLG flakes, are effective alternatives to FTO/Pt counter electrodes for DSSCs for both outdoor and indoor applications.

Published
2019
Full Text
View/download PDF

6. Exfoliation of Few-Layer Black Phosphorus in Low-Boiling-Point Solvents and Its Application in Li-Ion Batteries

Author

Castillo, Antonio Esau Del Rio, Pellegrini, Vittorio, Sun, Haiyan, Buha, Joka, Dinh, Duc Anh, Lago, Emanuele, Ansaldo, Alberto, Capasso, Andrea, Manna, Liberato, and Bonaccorso, Francesco

Subjects
Condensed Matter - Materials Science
Abstract

The liquid-phase exfoliation (LPE) of black phosphorus (BP) is a strategic route for the large-scale production of phosphorene and few-layer BP (FL-BP) flakes. The exploitation of this exfoliated material in cutting-edge technologies, e.g., in flexible electronics and energy storage, is however limited by the fact that the LPE of BP is usually carried out at a high boiling point and in toxic solvents. In fact, the solvent residual is detrimental to device performance in real applications; thus, complete solvent removal is critical. Here, we tackle these issues by exfoliating BP in different low boiling-point solvents. Among these solvents, we find that acetone also provides a high concentration of exfoliated BP, leading to the production of FL-BP flakes with an average lateral size and thickness of c.a. 30 and 7 nm, respectively. The use of acetone to produce less defective few-layer BP flakes (FL-BPacetone) from bulk crystals is a straightforward process which enables the rapid preparation of homogeneous thin films thanks to the fast solvent evaporation. The ratio of edge to bulk atoms for the BP flakes here produced, combined with the use of low-boiling-point solvents for the exfoliation process suggests that these thin films are promising anodes for lithium-ion batteries. To this end, we tested Li-ion half cells with FL-BPacetone anodes achieving a reversible specific capacity of 480 mAh/g at a current density of 100 mA/g, over 100 charge/discharge cycles. Moreover, a reversible specific capacity of 345 mAh/g is achieved for the FL-BPacetone-based anode at a high current density (i.e., 1 A/g). These findings indicate that the FL-BPacetone-based battery is promising with regards to the design of fast charge/discharge devices. Overall, the presented process is a step forward toward the fabrication of phosphorene-based devices., Comment: 30 pages, 11 images

Published
2018
Full Text
View/download PDF

7. Few-layer MoS2 flakes as hole-selective layer for solution-processed hybrid organic hydrogen-evolving photocathodes

Author

Bellani, Sebastiano, Najafi, Leyla, Castillo, Antonio Esau Del Rio, Capasso, Andrea, Antognazza, Maria Rosa, and Bonaccorso, Francesco

Subjects
Physics - Applied Physics, Condensed Matter - Materials Science
Abstract

High-efficiency organic photocathodes, based on regioregular poly(3-hexylthiophene) and phenyl-C61-butyric acid methyl ester (rr-P3HT:PCBM) bulk heterojunction sandwiched between charge-selective layers, are emerging as efficient and low-cost devices for solar hydrogen production by water splitting. Nevertheless, stability issues of the materials used as charge-selective layers are hampering the realization of long-lasting photoelectrodes, pointing out the need to investigate novel and stable materials. Here, we propose MoS2 nano-flakes, produced by Li-aided exfoliation of bulk counterpart, as efficient atomic-thick hole-selective layer for rr-P3HT:PCBM-based photocathodes. We carried out a p-type chemical doping to tune on-demand the MoS2 Fermi level in order to match the highest occupied molecular orbital level of the rr-P3HT, thus easing the hole collection at the electrode. The as-prepared p-doped MoS2-based photocathodes reached a photocurrent of 1.21 mA cm-2 at 0 V vs. RHE, a positive onset potential of 0.56 V vs. RHE and a power-saved figure of merit of 0.43%, showing a 6.1-fold increase with respect to pristine MoS2-based photocathodes, under simulated 1 Sun illumination. Operational activity of the photocathodes over time and under 1 Sun illumination revealed a progressive stabilization of the photocurrents at 0.49 mA cm-2 at 0 V vs. RHE. These results pave the way towards the exploitation of layered crystals as efficiency-boosters for scalable hybrid organic H2-evolving photoelectrochemical cells., Comment: 33 pages, 16 figures

Published
2018
Full Text
View/download PDF

9. Sustainable graphene production for solution-processed microsupercapacitors and multipurpose flexible electronics

Author

Sankar, Siva Nemala, primary, Fernandes, João, additional, Rodrigues, João, additional, Lopes, Vicente, additional, Pinto, Rui M.R., additional, Vinayakumar, K.B., additional, Placidi, Ernesto, additional, De Bellis, Giovanni, additional, Alpuim, Pedro, additional, Sampaio, Rui S., additional, Montemor, Maria F., additional, and Capasso, Andrea, additional

Published
2024
Full Text
View/download PDF

10. Eco‐Friendly Production of 2D Ti3C2Tx MXene and Cytotoxicity Mitigation Toward Biomedical Applications.

Author

Sankar, Siva Nemala, Araujo, Guilherme, Fernandes, João, Cerqueira, Fatima, Alpuim, Pedro, Ribeiro, Ana R., Lebre, Filipa, Alfaro‐Moreno, Ernesto, Placidi, Ernesto, Marras, Sergio, and Capasso, Andrea

Subjects
CELL morphology, CYTOTOXINS, SERUM albumin, CELL survival, CELL lines, KERATINOCYTE differentiation
Abstract

2D MXenes find applications in several technology fields. Solution processing techniques can facilitate the integration of these materials within the technological supply chain. Here, a highly concentrated (up to 1.5 g L−1) and stable dispersion of 2D Ti3C2Tx MXene flakes is produced by an environmentally friendly liquid phase exfoliation process (LPE) in dihydrolevoglucosenone (Cyrene). The flakes preserve their elemental composition after 6 months, while those exfoliated in N‐Methyl‐2‐pyrrolidone (NMP), a commonly used solvent, undergo significant oxidation. The cytotoxicity of the MXene flakes in Cyrene and in NMP is investigated by assessing the cellular viability in a human keratinocyte (HaCaT) cell line, which is a relevant model for skin applications. The data show that the MXene flakes in Cyrene induce cytotoxic effects for a dose > 1 µg cm−2, as similarly observed for the MXene flakes in NMP. Efforts are made to overcome this by collecting the MXene flakes and redispersing them in a solution of bovine serum albumin (BSA). MXene in BSA does not affect cellular viability and cell morphology, possibly due to the formation of a protective protein corona around the individual MXene flakes. These findings illustrate an environmentally friendly strategy to produce biocompatible 2D MXene for biomedical applications. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

15. Frailty, psychological well‐being, and social isolation in older adults with cognitive impairment during the SARS‐CoV‐2 pandemic: data from the GeroCovid initiative

Author

Terziotti, Camilla, primary, Ceolin, Chiara, additional, Devita, Maria, additional, Raffaelli, Cecilia, additional, Antenucci, Sara, additional, Bazzano, Salvatore, additional, Capasso, Andrea, additional, Castellino, Manuela, additional, Signore, Stefania Del, additional, Lubian, Francesca, additional, Maiotti, Mariangela, additional, Monacelli, Fiammetta, additional, Mormile, Maria Teresa, additional, Sgarito, Claudia, additional, Vella, Filomena, additional, Sergi, Giuseppe, additional, Gareri, Pietro, additional, Trevisan, Caterina, additional, Bellio, Andrea, additional, Fini, Filippo, additional, Malara, Alba, additional, Mossello, Enrico, additional, Fumagalli, Stefano, additional, Volpato, Stefano, additional, Monzani, Fabio, additional, Bellelli, Giuseppe, additional, Zia, Gianluca, additional, Incalzi, Raffaele Antonelli, additional, and Coin, Alessandra, additional

Published
2023
Full Text
View/download PDF

19. Stable Graphene Membranes for Selective Ion Transport and Emerging Contaminants Removal in Water

Author

Sankar, Siva Nemala, primary, Fernandes, João, additional, dos Santos, Marília Barreiros, additional, Espiña, Begoña, additional, Alpuim, Pedro, additional, Díez, Ander García, additional, Lanceros‐Mendez, Senentxu, additional, Saini, Lalita, additional, Kaushik, Suvigya, additional, Kalon, Gopinadhan, additional, and Capasso, Andrea, additional

Published
2023
Full Text
View/download PDF

21. Frailty, psychological well-being, and social isolation in older adults with cognitive impairment during the SARS-CoV-2 pandemic: data from the GeroCovid initiative

Author

Terziotti, C, Ceolin, C, Devita, M, Raffaelli, C, Antenucci, S, Bazzano, S, Capasso, A, Castellino, M, Signore, S, Lubian, F, Maiotti, M, Monacelli, F, Mormile, M, Sgarito, C, Vella, F, Sergi, G, Gareri, P, Trevisan, C, Bellio, A, Fini, F, Malara, A, Mossello, E, Fumagalli, S, Volpato, S, Monzani, F, Bellelli, G, Zia, G, Incalzi, R, Coin, A, Terziotti, Camilla, Ceolin, Chiara, Devita, Maria, Raffaelli, Cecilia, Antenucci, Sara, Bazzano, Salvatore, Capasso, Andrea, Castellino, Manuela, Signore, Stefania Del, Lubian, Francesca, Maiotti, Mariangela, Monacelli, Fiammetta, Mormile, Maria Teresa, Sgarito, Claudia, Vella, Filomena, Sergi, Giuseppe, Gareri, Pietro, Trevisan, Caterina, Bellio, Andrea, Fini, Filippo, Malara, Alba, Mossello, Enrico, Fumagalli, Stefano, Volpato, Stefano, Monzani, Fabio, Bellelli, Giuseppe, Zia, Gianluca, Incalzi, Raffaele Antonelli, Coin, Alessandra, Terziotti, C, Ceolin, C, Devita, M, Raffaelli, C, Antenucci, S, Bazzano, S, Capasso, A, Castellino, M, Signore, S, Lubian, F, Maiotti, M, Monacelli, F, Mormile, M, Sgarito, C, Vella, F, Sergi, G, Gareri, P, Trevisan, C, Bellio, A, Fini, F, Malara, A, Mossello, E, Fumagalli, S, Volpato, S, Monzani, F, Bellelli, G, Zia, G, Incalzi, R, Coin, A, Terziotti, Camilla, Ceolin, Chiara, Devita, Maria, Raffaelli, Cecilia, Antenucci, Sara, Bazzano, Salvatore, Capasso, Andrea, Castellino, Manuela, Signore, Stefania Del, Lubian, Francesca, Maiotti, Mariangela, Monacelli, Fiammetta, Mormile, Maria Teresa, Sgarito, Claudia, Vella, Filomena, Sergi, Giuseppe, Gareri, Pietro, Trevisan, Caterina, Bellio, Andrea, Fini, Filippo, Malara, Alba, Mossello, Enrico, Fumagalli, Stefano, Volpato, Stefano, Monzani, Fabio, Bellelli, Giuseppe, Zia, Gianluca, Incalzi, Raffaele Antonelli, and Coin, Alessandra

Abstract

Background: The containment measures linked to the COVID-19 pandemic negatively affected the phyco-physical well-being of the population, especially older adults with neurocognitive disorders (NCDs). This study aims to evaluate whether the frailty of NCD patients was associated with different changes in multiple health domains, in particular in relation to loneliness and social isolation, pre- and post-lockdown. Materials and Methods: Patients were recruited from 10 Italian Centers for Cognitive Disorders and Dementia. Data were collected in the pre-pandemic period (T0), during the pandemic lockdown (T1), and 6–9 months post-lockdown (T2). The UCLA Loneliness Scale-3, Activities of Daily Living (ADL), Instrumental ADL (IADL), Mini-Mental State Examination, and Neuropsychiatric Inventory (NPI) were administered. Caregivers' burden was also tested. Patients were categorized as non-frail, pre-frail, and frail according to the Fatigue, Resistance, Ambulation, Illness, and Loss of Weight scale. Results: The sample included 165 subjects (61.9% women, mean age 79.5 ± 4.9 years). In the whole sample, the ADL, IADL, and NPI scores significantly declined between T0 and T2. There were no significative variations in functional and cognitive domains between the frail groups. During lockdown we recorded higher Depression Anxiety Stress Scales and Perceived Stress Scale scores in frail people. In multivariable logistic regression, frailty was associated with an increase in social isolation, and a loss of IADL. Conclusions: We observed a global deterioration in functional and neuro-psychiatric domains irrespective of the degree of frailty. Frailty was associated with the worsening of social isolation during lockdown. Frail patients and their caregivers seemed to experience more anxiety and stress disorders during SARS-CoV-2 pandemic.

Published
2023

22. Bipolar Resistive Switching in 2D MoSe2Grown by Atmospheric Pressure Chemical Vapor Deposition

Author

Fernandes, João, Grzonka, Justyna, Araújo, Guilherme, Schulman, Alejandro, Silva, Vitor, Rodrigues, João, Santos, João, Bondarchuk, Oleksandr, Ferreira, Paulo, Alpuim, Pedro, and Capasso, Andrea

Abstract

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) are highly promising nanomaterials for various electronic devices such as field-effect transistors, junction diodes, tunneling devices, and, more recently, memristors. 2D MoSe2stands out for having high electrical conductivity, charge carrier mobility, and melting point. While these features make it particularly appropriate as a switching layer in memristive devices, reliable and scalable production of large-area 2D MoSe2still represents a challenge. In this study, we manufacture 2D MoSe2films by atmospheric-pressure chemical vapor deposition and investigate them on the atomic scale. We selected and transferred MoSe2bilayer to serve as a switching layer between asymmetric Au–Cu electrodes in miniaturized crossbar vertical memristors. The electrochemical metallization devices showed forming-free, bipolar resistive switching at low voltages, with clearly identifiable nonvolatile states. Other than low-power neuromorphic computing, low switching voltages approaching the range of biological action potentials could unlock hybrid biological interfaces.

Published
2024
Full Text
View/download PDF

28. Strain-modulated optical response in 2D MoSe2 made by Na-assisted CVD on glass

Author

Rodrigues, João, Grzonka, Justyna, Fernandes, João, Santos, João, Bondarchuk, Oleksandr, Ferreira, Paulo, Alpuim, P., Capasso, Andrea, and Universidade do Minho

Subjects
Science & Technology, Ciências Naturais::Ciências Físicas
Abstract

Extended investigations on 2D transition metal dichalcogenides (TMDCs) have opened sound possibilities to apply these materials in several technological fields such as sensing. To this end, fully reproducible methods for the wafer-scale production of crystalline and uniform 2D TMDCs are in demand. In this work, atomically thin MoSe2 was grown by atmospheric-pressure chemical vapor deposition using the Na-assisted process with Se powder and Mo foil precursors on a glass substrate. The samples were extensively characterized via Raman and photoluminescence spectroscopy, atomic force microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy. The MoSe2 samples consist of submillimeter, monolayer single-crystals with 2H phase configuration. Being monolayer and crystalline, the samples exhibit well-defined and intense photoluminescence. CVD-grown 2D MoSe2 was integrated into a device with strain-tunable optical properties and tested. Under tensile strain (in the range of 0.2%–0.4%), the spectral emission responded to an in-plane strain with marked peak shifts toward lower energies for increasing levels of strain (∼3 and ∼2 nm shift for the main PL component at 0.2% and 0.4%, respectively), indicating a reduction of the bandgap., We acknowledge the financial support of the project “GEMIS—Graphene-enhanced Electro Magnetic Interference Shielding” with Reference No. POCI-01-0247-FEDER-045939, co-funded by COMPETE 2020—Operational Programme for Competitiveness and Internationalization and FCT—Science and Technology Foundation, under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund. This work was supported by FCT, through IDMEC-Mechanical Engineering Institute, under LAETA-Associate Laboratory of Energy, Transports and Aeronautics, Project No. UIDB/50022/2020 and via the Strategic Funding UIDB/04650/2020. We thank Dr. S. Sadewasser and Mr. B. Baumgartner for their assistance in preliminary experiments.

Published
2022

30. Understanding 2D MoSe2 grown by CVD

Author

Fernandes, João, primary, Grzonka, Justyna, additional, Rodrigues, João, additional, Santos, João, additional, Bondarchuk, Oleksandr, additional, Ferreira, Paulo, additional, Alpuim, Pedro, additional, and Capasso, Andrea, additional

Published
2022
Full Text
View/download PDF

33. Enhanced Photoluminescence in Transition Metal Dichalcogenides Monolayers by Gold Nanoparticle Supercrystals

Author

Joao Rodriguez, Molet, Pau, Scarabelli, Leonardo, Capasso, Andrea, Mihi, Agust��n, Alpuim, Pedro, and Garcia-Pomar, Juan Luis

Subjects
photonics, photoluminescence, transition metal dichalcogenide
Abstract

We developed a nanostructure to enhance the photoluminescence intensity of two-dimensional monolayers of transition metal dichalcogenides based on plasmonic supercrystal arrays. These plasmonic supercrystal arrays are deposited on top the monolayers by means of a template-assisted assembly of gold nanospheres with patterned polydimethylsiloxane molds [1]. These supercrystals arrays consist on square arrays of hexagonally packed gold nanoparticles (50 nm of diameter) which exhibit well-defined surface lattice resonance modes that can be tuned from the visible through the near-infrared by simple variation of the lattice parameter. This tunability can be used to enhance the photoluminescence emission of different transition metal dichalcogenides monolayers. So, as proof of concept, the photoluminescence signal of the monolayer MoS2 and MoSe2 can be significantly enhanced up to 5-6-fold coupling the frequency of the surface latticeresonance of the plasmonic supercrystal to the frequency emission of the transition metal dichalcogenides monolayer. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 840064

Published
2021
Full Text
View/download PDF

34. Solution-Processed Functionalized Graphene Film Prepared by Vacuum Filtration for Flexible NO 2 Sensors.

Author

Dieng, Mbaye, Sankar, Siva, Ni, Pingping, Florea, Ileana, Alpuim, Pedro, Capasso, Andrea, Yassar, Abderrahim, and Bouanis, Fatima Zahra

Subjects
POLYVINYLIDENE fluoride, GLOBAL Positioning System, METAL phthalocyanines, RAMAN spectroscopy technique, ATOMIC force microscopy, DETECTORS, GRAPHENE
Abstract

Large-scale production of graphene nanosheets (GNSs) has led to the availability of solution-processable GNSs on the commercial scale. The controlled vacuum filtration method is a scalable process for the preparation of wafer-scale films of GNSs, which can be used for gas sensing applications. Here, we demonstrate the use of this deposition method to produce functional gas sensors, using a chemiresistor structure from GNS solution-based techniques. The GNS suspension was prepared by liquid-phase exfoliation (LPE) and transferred to a polyvinylidene fluoride (PVDF) membrane. The effect of non-covalent functionalization with Co-porphyrin and Fe-phthalocyanines on the sensor properties was studied. The pristine and functionalized GNS films were characterized using different techniques such as Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and electrical characterizations. The morphological and spectroscopic analyses both confirm that the molecules (Co-porphyrin and Fe-phthalocyanine) were successfully adsorbed onto the GNSs surface through π-π interactions. The chemiresistive sensor response of functionalized GNSs toward the low concentrations of nitrogen dioxide (NO2) (0.5–2 ppm) was studied and compared with those of the film of pristine GNSs. The tests on the sensing performance clearly showed sensitivity to a low concentration of NO2 (5 ppm). Furthermore, the chemical modification of GNSs significantly improves NO2 sensing performance compared to the pristine GNSs. The sensor response can be modulated by the type of adsorbed molecules. Indeed, Co-Por exhibited negative responsiveness (the response of Co-Por-GNS sensors and pristine GNS devices was 13.1% and 15.6%, respectively, after exposure to 0.5 ppm of NO2). Meanwhile, Fe-Phc-GNSs induced the opposite behavior resulting in an increase in the sensor response (the sensitivity was 8.3% and 7.8% of Fe-Phc-GNSs and pristine GNSs, respectively, at 0.5 ppm NO2 gas). [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

36. Efficient ReSe2 Photodetectors with CVD Single-Crystal Graphene Contacts

Author

Silva, Bruna, primary, Rodrigues, João, additional, Sompalle, Balaji, additional, Liao, Chun-Da, additional, Nicoara, Nicoleta, additional, Borme, Jérôme, additional, Cerqueira, Fátima, additional, Claro, Marcel, additional, Sadewasser, Sascha, additional, Alpuim, Pedro, additional, and Capasso, Andrea, additional

Published
2021
Full Text
View/download PDF

39. Neuronal Networks: Interactions between Primary Neurons and Graphene Films with Different Structure and Electrical Conductivity (Adv. Funct. Mater. 11/2021)

Author

Capasso, Andrea, primary, Rodrigues, João, additional, Moschetta, Matteo, additional, Buonocore, Francesco, additional, Faggio, Giuliana, additional, Messina, Giacomo, additional, Kim, Min Jung, additional, Kwon, Junyoung, additional, Placidi, Ernesto, additional, Benfenati, Fabio, additional, Bramini, Mattia, additional, Lee, Gwan‐Hyoung, additional, and Lisi, Nicola, additional

Published
2021
Full Text
View/download PDF

40. Double grain boundary configurations on graphite surfaces

Author

Capasso, Andrea, Muñoz-Rojas, F., Gupta, B., Motta, N., Placidi, E., Capasso, Andrea, Muñoz-Rojas, F., Gupta, B., Motta, N., and Placidi, E.

Abstract

We investigated the atomic structure of different kinds of grain boundaries on highly oriented pyrolytic graphite (HOPG) by scanning tunneling microscopy. We categorized several grain boundary configurations as a function of the misorientation angle between the adjacent grains, highlighting the occurrence of double grain boundaries (i.e., systems of two grain boundaries separated by a nanometric-scale inner region with specific atomic arrangement) for misorientation angles in the range 22°–32°. By using Molecular Dynamics simulations, we analyzed the structure and energy stability of single and double grain boundaries according to the misorientation angle. The experimental evidence is corroborated by Molecular Dynamics results and total energy calculations, which found a comparable stability between single and double grain boundaries for the same misorientation angle range. Our combination of experimental measurements and theoretical calculation extends the understanding of the structural configuration of large angle grain boundaries beyond the range of misorientation angles reported to date.

Published
2020

43. An ab initio study of hydroxylated graphane.

Author

Buonocore, Francesco, Capasso, Andrea, and Lisi, Nicola

Subjects
*GRAPHENE oxide, *HYDROXYLATION, *COVALENT bonds, *FUNCTIONAL groups, *HYDROGEN, *OXYGEN
Abstract

Graphene-based derivatives with covalent functionalization and well-defined stoichiometry are highly desirable in viewof their application as functional surfaces. Here, we have evaluated by ab initio calculations the energy of formation and the phase diagram of hydroxylated graphane structures, i.e., fully functionalized graphene derivatives coordinated with -H and -OH groups. We compared these structures to different hydrogenated and non-hydrogenated graphene oxide derivatives, with high level of epoxide and hydroxyl groups functionalization. Based on our calculations, stable phases of hydroxylated graphane with lowand high contents of hydrogen are demonstrated for high oxygen and hydrogen partial pressure, respectively. Stable phases of graphene oxide with a mixed carbon hybridization are also found. Notably, the synthesis of hydroxylated graphane has been recently reported in the literature. [ABSTRACT FROM AUTHOR]

Published
2017
Full Text
View/download PDF

44. Strain-modulated optical response in 2D MoSe2 made by Na-assisted CVD on glass.

Author

Rodrigues, João, Grzonka, Justyna, Fernandes, João, Santos, João, Bondarchuk, Oleksandr, Ferreira, Paulo, Alpuim, Pedro, and Capasso, Andrea

Subjects
X-ray photoelectron spectroscopy, CHEMICAL vapor deposition, TRANSMISSION electron microscopy, OPTICAL properties, OPTICAL devices, ATOMIC force microscopy
Abstract

Extended investigations on 2D transition metal dichalcogenides (TMDCs) have opened sound possibilities to apply these materials in several technological fields such as sensing. To this end, fully reproducible methods for the wafer-scale production of crystalline and uniform 2D TMDCs are in demand. In this work, atomically thin MoSe2 was grown by atmospheric-pressure chemical vapor deposition using the Na-assisted process with Se powder and Mo foil precursors on a glass substrate. The samples were extensively characterized via Raman and photoluminescence spectroscopy, atomic force microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy. The MoSe2 samples consist of submillimeter, monolayer single-crystals with 2H phase configuration. Being monolayer and crystalline, the samples exhibit well-defined and intense photoluminescence. CVD-grown 2D MoSe2 was integrated into a device with strain-tunable optical properties and tested. Under tensile strain (in the range of 0.2%–0.4%), the spectral emission responded to an in-plane strain with marked peak shifts toward lower energies for increasing levels of strain (∼3 and ∼2 nm shift for the main PL component at 0.2% and 0.4%, respectively), indicating a reduction of the bandgap. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

45. Interactions between Primary Neurons and Graphene Films with Different Structure and Electrical Conductivity

Author

Capasso, Andrea, primary, Rodrigues, João, additional, Moschetta, Matteo, additional, Buonocore, Francesco, additional, Faggio, Giuliana, additional, Messina, Giacomo, additional, Kim, Min Jung, additional, Kwon, Junyoung, additional, Placidi, Ernesto, additional, Benfenati, Fabio, additional, Bramini, Mattia, additional, Lee, Gwan‐Hyoung, additional, and Lisi, Nicola, additional

Published
2020
Full Text
View/download PDF

49. CVD-graphene/graphene flakes dual-films as advanced DSSC counter electrodes

Author

Capasso, Andrea, primary, Bellani, Sebastiano, additional, Palma, Alessandro Lorenzo, additional, Najafi, Leyla, additional, Del Rio Castillo, Antonio Esaù, additional, Curreli, Nicola, additional, Cinà, Lucio, additional, Miseikis, Vaidotas, additional, Coletti, Camilla, additional, Calogero, Giuseppe, additional, Pellegrini, Vittorio, additional, Di Carlo, Aldo, additional, and Bonaccorso, Francesco, additional

Published
2019
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results