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Silver nanoparticles (AgNPs) can be used as a surface plasmon resonance (SPR) colorimetric sensor; the correlation between the SPR phenomenon and the aggregation state of nanoparticle allows the real-time detection of a target molecule. Surface functionalization of NPs with proper molecular baits is often performed to establish the selectivity of the sensor. This work reports on the synthesis of AgNPs under reducing conditions and on the functionalization thereof with mercaptoundecanoic acid (11-MUA). UV-VIS Spectroscopy confirmed the formation of AgNPs, eliciting a surface plasmon absorption band (SPAB) at 393 nm that shifted to 417 nm upon surface coating. Dynamic light scattering was used to investigate the surface coatings; moreover, pelleted [email protected] nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analyzers (EDX), and infrared spectroscopy to corroborate the presence of 11MUA on the surface. Most interestingly, the resulting [email protected] selectively detected micromolar levels of Ni2+, also in the presence of other cations such as Mn2+, Co2+, Cd2+, Cu2+, Zn2+, Fe2+, Hg2+, Pb2+, and Cr3+.
Andrea Rossi; Marco Zannotti; Massimiliano Cuccioloni; Marco Minicucci; Laura Petetta; Mauro Angeletti; Rita Giovannetti. Silver Nanoparticle-Based Sensor for the Selective Detection of Nickel Ions. Nanomaterials 2021, 11, 1733 .
AMA StyleAndrea Rossi, Marco Zannotti, Massimiliano Cuccioloni, Marco Minicucci, Laura Petetta, Mauro Angeletti, Rita Giovannetti. Silver Nanoparticle-Based Sensor for the Selective Detection of Nickel Ions. Nanomaterials. 2021; 11 (7):1733.
Chicago/Turabian StyleAndrea Rossi; Marco Zannotti; Massimiliano Cuccioloni; Marco Minicucci; Laura Petetta; Mauro Angeletti; Rita Giovannetti. 2021. "Silver Nanoparticle-Based Sensor for the Selective Detection of Nickel Ions." Nanomaterials 11, no. 7: 1733.
The sensing behavior of a thin film composed of metal-free 5, 10, 15, 20-tetrakis (p-hydroxy phenyl) porphyrin and zinc phthalocyanine complex towards m-xylene, styrene, and HCl vapors in a homemade planar optical waveguide (POWG), was studied at room temperature. The thin film was deposited on the surface of potassium ion-exchanged glass substrate, using vacuum spin-coating method, and a semiconductor laser light (532 nm) as the guiding light. Opto-chemical changes of the film exposing with hydrochloric gas, m-xylene, and styrene vapor, were analyzed firstly with UV-Vis spectroscopy. The fabricated POWG shows good correlation between gas exposure response and absorbance change within the gas concentration range 10–1500 ppm. The limit of detection calculated from the logarithmic calibration curve was proved to be 11.47, 21.08, and 14.07 ppm, for HCl gas, m-xylene, and styrene vapors, respectively. It is interesting to find that the film can be recovered to the initial state with trimethylamine vapors after m-xylene, styrene exposures as well as HCl exposure. The gas-film interaction mechanism was discussed considering protonation and π-π stacking with planar aromatic analyte molecules.
Nuerguli Kari; Marco Zannotti; Rita Giovannetti; Patigu Maimaiti; Patima Nizamidin; Shawket Abliz; Abliz Yimit. Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide. Nanomaterials 2021, 11, 1634 .
AMA StyleNuerguli Kari, Marco Zannotti, Rita Giovannetti, Patigu Maimaiti, Patima Nizamidin, Shawket Abliz, Abliz Yimit. Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide. Nanomaterials. 2021; 11 (7):1634.
Chicago/Turabian StyleNuerguli Kari; Marco Zannotti; Rita Giovannetti; Patigu Maimaiti; Patima Nizamidin; Shawket Abliz; Abliz Yimit. 2021. "Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide." Nanomaterials 11, no. 7: 1634.
In the last decade, metal nanoparticles (NPs) have gained significant interest in the field of biotechnology due to their unique physiochemical properties and potential uses in a wide range of applications. Metal NP synthesis using microorganisms has emerged as an eco-friendly, clean, and viable strategy alternative to chemical and physical approaches. Herein, an original and efficient route for the microbial synthesis of copper NPs using bacterial strains newly isolated from an Antarctic consortium is described. UV-visible spectra of the NPs showed a maximum absorbance in the range of 380–385 nm. Transmission electron microscopy analysis showed that these NPs are all monodispersed, spherical in nature, and well segregated without any agglomeration and with an average size of 30 nm. X-ray powder diffraction showed a polycrystalline nature and face centered cubic lattice and revealed characteristic diffraction peaks indicating the formation of CuONPs. Fourier-transform infrared spectra confirmed the presence of capping proteins on the NP surface that act as stabilizers. All CuONPs manifested antimicrobial activity against various types of Gram-negative; Gram-positive bacteria; and fungi pathogen microorganisms including Escherichia coli, Staphylococcus aureus, and Candida albicans. The cost-effective and eco-friendly biosynthesis of these CuONPs make them particularly attractive in several application from nanotechnology to biomedical science.
Maria John; Joseph Nagoth; Marco Zannotti; Rita Giovannetti; Alessio Mancini; Kesava Ramasamy; Cristina Miceli; Sandra Pucciarelli. Biogenic Synthesis of Copper Nanoparticles Using Bacterial Strains Isolated from an Antarctic Consortium Associated to a Psychrophilic Marine Ciliate: Characterization and Potential Application as Antimicrobial Agents. Marine Drugs 2021, 19, 263 .
AMA StyleMaria John, Joseph Nagoth, Marco Zannotti, Rita Giovannetti, Alessio Mancini, Kesava Ramasamy, Cristina Miceli, Sandra Pucciarelli. Biogenic Synthesis of Copper Nanoparticles Using Bacterial Strains Isolated from an Antarctic Consortium Associated to a Psychrophilic Marine Ciliate: Characterization and Potential Application as Antimicrobial Agents. Marine Drugs. 2021; 19 (5):263.
Chicago/Turabian StyleMaria John; Joseph Nagoth; Marco Zannotti; Rita Giovannetti; Alessio Mancini; Kesava Ramasamy; Cristina Miceli; Sandra Pucciarelli. 2021. "Biogenic Synthesis of Copper Nanoparticles Using Bacterial Strains Isolated from an Antarctic Consortium Associated to a Psychrophilic Marine Ciliate: Characterization and Potential Application as Antimicrobial Agents." Marine Drugs 19, no. 5: 263.
Chemical composition in seawater of marine sediments, as well as the physical properties and chemical composition of soils, influence the phase behavior of natural gas hydrate by disturbing the hydrogen bond network in the water-rich phase before hydrate formation. In this article, some marine sediments samples, collected in National Antarctic Museum in Trieste, were analyzed and properties such as pH, conductivity, salinity, and concentration of main elements of water present in the sediments are reported. The results, obtained by inductively coupled plasma-mass spectrometry (ICP-MS) and ion chromatography (IC) analysis, show that the more abundant cation is sodium and, present in smaller quantities, but not negligible, are calcium, potassium, and magnesium, while the more abundant anion is chloride and sulfate is also appreciable. These results were successively used to determine the thermodynamic parameters and the effect on salinity of water on hydrates’ formation. Then, hydrate formation was experimentally tested using a small-scale apparatus, in the presence of two different porous media: a pure silica sand and a silica-based natural sand, coming from the Mediterranean seafloor. The results proved how the presence of further compounds, rather than silicon, as well as the heterogeneous grainsize and porosity, made this sand a weak thermodynamic and a strong kinetic inhibitor for the hydrate formation process.
Alberto Gambelli; Umberta Tinivella; Rita Giovannetti; Beatrice Castellani; Michela Giustiniani; Andrea Rossi; Marco Zannotti; Federico Rossi. Observation of the Main Natural Parameters Influencing the Formation of Gas Hydrates. Energies 2021, 14, 1803 .
AMA StyleAlberto Gambelli, Umberta Tinivella, Rita Giovannetti, Beatrice Castellani, Michela Giustiniani, Andrea Rossi, Marco Zannotti, Federico Rossi. Observation of the Main Natural Parameters Influencing the Formation of Gas Hydrates. Energies. 2021; 14 (7):1803.
Chicago/Turabian StyleAlberto Gambelli; Umberta Tinivella; Rita Giovannetti; Beatrice Castellani; Michela Giustiniani; Andrea Rossi; Marco Zannotti; Federico Rossi. 2021. "Observation of the Main Natural Parameters Influencing the Formation of Gas Hydrates." Energies 14, no. 7: 1803.
Substituent effect on optical gas sensing performance in porphyrin-based optical waveguide detection system was studied by molecular dynamics simulation (MDS), absorption/emission spectrum analysis, and optical waveguide (OWG) detection. The affinities of porphyrin with seven types of substituents (–H, –OH, –tBu, –COOH, –NH2, –OCH3, –SO3−) on para position of meso-phenyl porphyrin toward gas molecules in adsorption process were studied in different size of boxes with the same pressure and concentration. Analyte gases (CO2, H2S, HCl, NO2) were exposed to porphyrin film in absorption spectrophotometer, and in OWG with evanescent field excited by a guiding laser light with 670 nm wavelength. The extent of interaction between host molecule and the guest analytes was analyzed by the number of gas molecules in vicinity of 0.3 nm around substituents of porphyrin molecules. Optical waveguide results reveal that sulfonate porphyrin is mostly responsive to hydrochloride, hydrosulfide gas and nitrogen dioxide gases with strong response intensity. Molecular dynamics and spectral analysis provide objective information about the molecular state and sensing properties. Molecular rearrangements induced by gas exposure was studied by spectral analysis and surface morphology before and after gas exposure taking hydrosulfide gas as an example. Film-gas interaction mechanism was discussed in terms of each gas and substituent group characters.
Nuerguli Kari; Marco Zannotti; Gulgina Mamtmin; Rita Giovannetti; Babak Minofar; David Řeha; Patigu Maimaiti; Buayishamu Kutilike; Abliz Yimit. Substituent Effect on Porphyrin Film-Gas Interaction by Optical Waveguide: Spectrum Analysis and Molecular Dynamic Simulation. Materials 2020, 13, 5613 .
AMA StyleNuerguli Kari, Marco Zannotti, Gulgina Mamtmin, Rita Giovannetti, Babak Minofar, David Řeha, Patigu Maimaiti, Buayishamu Kutilike, Abliz Yimit. Substituent Effect on Porphyrin Film-Gas Interaction by Optical Waveguide: Spectrum Analysis and Molecular Dynamic Simulation. Materials. 2020; 13 (24):5613.
Chicago/Turabian StyleNuerguli Kari; Marco Zannotti; Gulgina Mamtmin; Rita Giovannetti; Babak Minofar; David Řeha; Patigu Maimaiti; Buayishamu Kutilike; Abliz Yimit. 2020. "Substituent Effect on Porphyrin Film-Gas Interaction by Optical Waveguide: Spectrum Analysis and Molecular Dynamic Simulation." Materials 13, no. 24: 5613.
The purpose of this work was the optimization of the extraction from spent coffee grounds, specifically 100% Arabica coffee blends, using a desirability approach. Spent coffees were recovered after the preparation of the espresso coffee under the typical conditions used in coffee bars with a professional machine. Spent coffee was subjected to different extraction procedures in water: by changing the extraction temperature (60, 80, or 100 °C) and the solvent extraction volume (10, 20, 30 mL for 1 g of coffee) and by maintaining constant the extraction time (30 min). The ranges of the process parameters, as well as the solvent to be used, were established by running preliminary experiments not reported here. The variables of interest for the experimental screening design were the content of caffeine, trigonelline, and nicotinic acid, quantitatively determined from regression lines of standard solutions of known concentrations by a validated HPLC-VWD method. Since solvent extraction volumes and temperatures were revealed to be the most significant process variables, for the optimization of the extraction process, an approach based on Response Surface Methodology (RSM) was considered. In particular, a Box-Wilson Central Composite Design, commonly named central composite design (CCD), was used to find the optimal conditions of the extraction process. Moreover, the desirability approach was then applied to maximize the extraction efficiency by searching the optimal values (or at least the best compromise solution) for all three response variables simultaneously. Successively, the best extract, obtained in a volume of 20 mL of water at an extraction temperature of 80 °C, was analyzed for total phenol content (TPC) through the Folin–Ciocalteu assay, and the antioxidant capacities (AC) through the trolox equivalent (TE) antioxidant capacity (DPPH), ferric-ion reducing antioxidant parameter (FRAP), and radical cation scavenging activity and reducing power (ABTS). The TPC and the AC for spent coffee were high and comparable to the results obtained in previous similar studies. Then, the extract was evaluated by inductively coupled plasma mass spectrometry (ICP–MS), revealing that potassium was the most abundant element, followed by phosphorus, magnesium, calcium, sodium, and sulfur, while very low content in heavy metals was observed. Preliminary in vitro assays in keratinocyte HaCaT cells were carried out to assess the safety, in terms of cytotoxicity of spent coffee, and results showed that cell viability depends on the extract concentration: cell viability is unmodified up to a concentration of 0.3 mg/mL, over which it becomes cytotoxic for the cells. Spent coffee extract at 0.03 and 0.3 mg/mL showed the ability to reduce intracellular reactive oxygen species formation induced by hydrogen peroxide in HaCaT cells, suggesting its antioxidant activity at intracellular levels.
Maria Rosa Gigliobianco; Barbara Campisi; Dolores Vargas Peregrina; Roberta Censi; Gulzhan Khamitova; Simone Angeloni; Giovanni Caprioli; Marco Zannotti; Stefano Ferraro; Rita Giovannetti; Cristina Angeloni; Giulio Lupidi; Letizia Pruccoli; Andrea Tarozzi; Dario Voinovich; Piera Di Martino. Optimization of the Extraction from Spent Coffee Grounds Using the Desirability Approach. Antioxidants 2020, 9, 370 .
AMA StyleMaria Rosa Gigliobianco, Barbara Campisi, Dolores Vargas Peregrina, Roberta Censi, Gulzhan Khamitova, Simone Angeloni, Giovanni Caprioli, Marco Zannotti, Stefano Ferraro, Rita Giovannetti, Cristina Angeloni, Giulio Lupidi, Letizia Pruccoli, Andrea Tarozzi, Dario Voinovich, Piera Di Martino. Optimization of the Extraction from Spent Coffee Grounds Using the Desirability Approach. Antioxidants. 2020; 9 (5):370.
Chicago/Turabian StyleMaria Rosa Gigliobianco; Barbara Campisi; Dolores Vargas Peregrina; Roberta Censi; Gulzhan Khamitova; Simone Angeloni; Giovanni Caprioli; Marco Zannotti; Stefano Ferraro; Rita Giovannetti; Cristina Angeloni; Giulio Lupidi; Letizia Pruccoli; Andrea Tarozzi; Dario Voinovich; Piera Di Martino. 2020. "Optimization of the Extraction from Spent Coffee Grounds Using the Desirability Approach." Antioxidants 9, no. 5: 370.
A simple method to prepare silver nanoparticles (AgNPs) with different shapes and dimensions was optimized by using a one-step reduction method with NaBH4, TSC and PVP, with H2O2 acting as an oxidation agent, to etch the nanoparticles and produce different morphologies. A series of AgNPs were obtained with different colours, including yellow to green and passing through orange, red, violet and blue, that exhibited different localized surface plasmon resonance (LSPR) as analysed by UV–visible spectroscopy. The dimensions and morphologies of the nanostructures were characterized in detail by scanning electron microscopy (SEM) and dynamic light scattering (DLS) techniques. The characterizations showed different trends in the morphologies, starting from spherical to not well-defined structures, triangular nanoplates, hexagonal nanoplates and ultimately once again showing quasi-spherical shapes. The triangular nanoplates were tested as plasmon sensors for mercury ions in aqueous solution, and they showed an LSPR-blueshift with a change in colour from blue to violet. When a calibration curve was measured in the concentration range from 0.14 to 0.5 mg l−1, the nanoparticles showed good linearity between the Hg2+ concentration in the solutions and the LSPR blueshift, with a correlation factor R2 of 0.9978 and an LOD of 0.013 mg l−1 (64.9 nM).
Marco Zannotti; Vittorio Vicomandi; Andrea Rossi; Marco Minicucci; Stefano Ferraro; Laura Petetta; Rita Giovannetti. Tuning of hydrogen peroxide etching during the synthesis of silver nanoparticles. An application of triangular nanoplates as plasmon sensors for Hg2+ in aqueous solution. Journal of Molecular Liquids 2020, 309, 113238 .
AMA StyleMarco Zannotti, Vittorio Vicomandi, Andrea Rossi, Marco Minicucci, Stefano Ferraro, Laura Petetta, Rita Giovannetti. Tuning of hydrogen peroxide etching during the synthesis of silver nanoparticles. An application of triangular nanoplates as plasmon sensors for Hg2+ in aqueous solution. Journal of Molecular Liquids. 2020; 309 ():113238.
Chicago/Turabian StyleMarco Zannotti; Vittorio Vicomandi; Andrea Rossi; Marco Minicucci; Stefano Ferraro; Laura Petetta; Rita Giovannetti. 2020. "Tuning of hydrogen peroxide etching during the synthesis of silver nanoparticles. An application of triangular nanoplates as plasmon sensors for Hg2+ in aqueous solution." Journal of Molecular Liquids 309, no. : 113238.
Chemical and sensory peculiarities of monovarietal extra virgin olive oils (MEVOOs) from the cultivars (cvs.) Ascolana tenera (ASC), Coroncina (COR), Mignola (MIG), Piantone di Mogliano (MOG), and Raggia (RAG) from Marche region (Italy) are investigated. Their polar phenolic substances and α-tocopherol are analysed through high performance liquid chromatography with different detectors. Volatile substances, fatty acid composition, and squalene are analysed by gas chromatography coupled to mass spectrometry (MS) and to the flame ionization detector, respectively. Total antioxidant activity and sensory analysis were also performed. MOG showed high squalene content (on average 0.88 ± 0.16 g/100 g), high relative amount of α-copaene among volatiles, and the highest oleic acid percentage. MIG had high α-tocopherol content (on average 350.0 ± 57.6 mg kg−1) and high α-farnesene in the volatile fraction. ASC showed the highest sensory quality and the lignan pinoresinol with higher concentration as compared to the other MEVOOs (p < 0.05), which resulted in a possible chemical marker for this cv. RAG was characterized by the sensory note of almond, which corresponds to its highest (E)-2-hexenal percentage. Sensory analysis and an antioxidant activity assay performed on a set of industrial extra virgin olive oils purchased in supermarkets, highlighted MEVOOs’ superiority from these points of view. Principal component analysis displays the main characteristics of the cvs. investigated.
Deborah Pacetti; Maria Chiara Boarelli; Rita Giovannetti; Stefano Ferraro; Paolo Conti; Barbara Alfei; Giovanni Caprioli; Massimo Ricciutelli; Gianni Sagratini; Donatella Fedeli; Rosita Gabbianelli; Dennis Fiorini. Chemical and Sensory Profiling of Monovarietal Extra Virgin Olive Oils from the Italian Marche Region. Antioxidants 2020, 9, 330 .
AMA StyleDeborah Pacetti, Maria Chiara Boarelli, Rita Giovannetti, Stefano Ferraro, Paolo Conti, Barbara Alfei, Giovanni Caprioli, Massimo Ricciutelli, Gianni Sagratini, Donatella Fedeli, Rosita Gabbianelli, Dennis Fiorini. Chemical and Sensory Profiling of Monovarietal Extra Virgin Olive Oils from the Italian Marche Region. Antioxidants. 2020; 9 (4):330.
Chicago/Turabian StyleDeborah Pacetti; Maria Chiara Boarelli; Rita Giovannetti; Stefano Ferraro; Paolo Conti; Barbara Alfei; Giovanni Caprioli; Massimo Ricciutelli; Gianni Sagratini; Donatella Fedeli; Rosita Gabbianelli; Dennis Fiorini. 2020. "Chemical and Sensory Profiling of Monovarietal Extra Virgin Olive Oils from the Italian Marche Region." Antioxidants 9, no. 4: 330.
In this work, we prepared different morphologies of silver nanoparticles: nanosphere, triangular nanoplates, hexagonal nanoplates, and quasi-spherical shapes, through one-step synthesis. Hydrogen peroxide was used as the oxidizing agent during the reduction of silver nitrate by sodium borohydride, in the presence of tri-sodium citrate and poly-vinyl-pyrrolidone. The obtained silver nanoparticles were fully characterized by UV-Vis spectroscopy, Dynamic Light Scattering and Scanning Electron Microscopy, and successfully used as Surface Enhanced Raman Scattering (SERS) substrates. The effect of shape and morphology on the Raman scattering enhancement was evaluated by using methylene blue as target molecules. The Raman measurements demonstrated that the prepared substrates are reliable and sensitive with analytical enhancement factors, estimated to be around 105 with a concentration of methylene blue 1 μM. When triangular and hexagonal nanoplates were tested with different concentrations of analyte, they demonstrated a good linearity in Raman intensity with a good detection of methylene blue 0.1 μM.
Marco Zannotti; Andrea Rossi; Rita Giovannetti. SERS Activity of Silver Nanosphere, Triangular Nanoplates, Hexagonal Nanoplates and Quasi-Spherical Nanoparticles: Effect of Shape and Morphology. Coatings 2020, 10, 288 .
AMA StyleMarco Zannotti, Andrea Rossi, Rita Giovannetti. SERS Activity of Silver Nanosphere, Triangular Nanoplates, Hexagonal Nanoplates and Quasi-Spherical Nanoparticles: Effect of Shape and Morphology. Coatings. 2020; 10 (3):288.
Chicago/Turabian StyleMarco Zannotti; Andrea Rossi; Rita Giovannetti. 2020. "SERS Activity of Silver Nanosphere, Triangular Nanoplates, Hexagonal Nanoplates and Quasi-Spherical Nanoparticles: Effect of Shape and Morphology." Coatings 10, no. 3: 288.
In this work, we studied the effect of inorganic ions occurring in natural waters on E. coli inactivation by solar and photo-Fenton processes, two crucial methods for drinking water treatment in sunny or developing countries. HCO3-,Cl-,SO42-,NO3-,NO2- and NH4+ were assessed at relevant concentrations for their inhibiting or facilitating role. The inactivation enhancement during solar disinfection (SODIS) was mainly attributed to the generation of HO• radicals produced during by excitation of NO3-,NO2-, while the HO• of photo-Fenton may be transformed into other radical species in presence of ions. Natural organic matter (NOM) was found to enhance both processes but also to hinder most of the enhancing ions, except for NO2-; modeling with the APEX software unveiled the inter-relations in the presence of NOM, and the possible inactivation activity by NO2•. The photo-Fenton inactivation was more significantly enhanced by ions than SODIS (besides the case of NO3-,NO2-), but both processes were found robust enough.
Elena Rommozzi; Stefanos Giannakis; Rita Giovannetti; Davide Vione; César Pulgarin. Detrimental vs. beneficial influence of ions during solar (SODIS) and photo-Fenton disinfection of E. coli in water: (Bi)carbonate, chloride, nitrate and nitrite effects. Applied Catalysis B: Environmental 2020, 270, 118877 .
AMA StyleElena Rommozzi, Stefanos Giannakis, Rita Giovannetti, Davide Vione, César Pulgarin. Detrimental vs. beneficial influence of ions during solar (SODIS) and photo-Fenton disinfection of E. coli in water: (Bi)carbonate, chloride, nitrate and nitrite effects. Applied Catalysis B: Environmental. 2020; 270 ():118877.
Chicago/Turabian StyleElena Rommozzi; Stefanos Giannakis; Rita Giovannetti; Davide Vione; César Pulgarin. 2020. "Detrimental vs. beneficial influence of ions during solar (SODIS) and photo-Fenton disinfection of E. coli in water: (Bi)carbonate, chloride, nitrate and nitrite effects." Applied Catalysis B: Environmental 270, no. : 118877.
Reduced Graphene Oxide (rGO) has been prepared from commercial graphene oxide by a thermal reduction method and NiO/rGO photocathodes was obtained by a mixed NiCl2/rGO sol gel-process by using different amount of rGO material. A detailed characterization of NiO/rGO films was carried out by SEM, Raman and surface analysis. BET analysis revealed that the optimum surface area of the films was between 0.0 to 0.3 mg of rGO, while the surface area was lower with increasing graphene content. Despite the lower surface area, in the presence of the higher amount of rGO material a higher dye uptake was detected, possibly due to a π-staking interaction between the phenyl group of the dye and the graphene sheets. The p-type dye-sensitized solar cells prepared from these films showed a gradual increase in JSC up to 2.6 mA/cm2 with the higher amount of rGO, and VOC of 125 mV; in this case the efficiency was almost 2 times higher with respect to the solar cell with NiO alone. An EIS study showed that the charge recombination resistance was lower in presence of the rGO but the hole lifetime was similar. This behavior suggests that the higher JSC obtained with the higher amount of rGO can be ascribed to the higher dye uptake, which leads to a higher concentration of holes in the photocathodes.
Marco Zannotti; Elisabetta Benazzi; Lee Stevens; Marco Minicucci; Lawrence Bruce; Colin Snape; Elizabeth A. Gibson; Rita Giovannetti. Reduced Graphene Oxide-NiO Photocathodes for p-Type Dye-Sensitized Solar Cells. ACS Applied Energy Materials 2019, 2, 7345 -7353.
AMA StyleMarco Zannotti, Elisabetta Benazzi, Lee Stevens, Marco Minicucci, Lawrence Bruce, Colin Snape, Elizabeth A. Gibson, Rita Giovannetti. Reduced Graphene Oxide-NiO Photocathodes for p-Type Dye-Sensitized Solar Cells. ACS Applied Energy Materials. 2019; 2 (10):7345-7353.
Chicago/Turabian StyleMarco Zannotti; Elisabetta Benazzi; Lee Stevens; Marco Minicucci; Lawrence Bruce; Colin Snape; Elizabeth A. Gibson; Rita Giovannetti. 2019. "Reduced Graphene Oxide-NiO Photocathodes for p-Type Dye-Sensitized Solar Cells." ACS Applied Energy Materials 2, no. 10: 7345-7353.
In this study, a green and facile thermal reduction of graphene oxide using an eco-friendly system of d-(+)-glucose and NH4OH for the preparation of reduced graphene oxide was described. The obtained reduced graphene oxide dispersion was characterized by SEM, Dynamic Light Scattering, Raman and X-Ray Photoelectron Spectroscopy. TiO2 nanoparticles and reduced graphene oxide nanocomposites were successively prepared and used in the preparation of heterogeneous photocatalysts that were characterized by Atomic Force Microscopy and Photoluminescence Spectroscopy and subsequently tested as visible light photocatalysts for the photodegradation of Alizarin Red S in water as target pollutant. Obtained results of photocatalytic tests regarding the visible light photocatalytic degradation of Alizarin Red S demonstrated that the use of reduced graphene oxide in combination with TiO2 led to a significant improvement for both adsorption of Alizarin Red S on the catalyst surface and photodegradation efficiencies when compared to those obtained with not doped TiO2.
Elena Rommozzi; Marco Zannotti; Rita Giovannetti; Chiara Anna D’Amato; Stefano Ferraro; Marco Minicucci; Roberto Gunnella; Andrea Di Cicco. Reduced Graphene Oxide/TiO2 Nanocomposite: From Synthesis to Characterization for Efficient Visible Light Photocatalytic Applications. Catalysts 2018, 8, 598 .
AMA StyleElena Rommozzi, Marco Zannotti, Rita Giovannetti, Chiara Anna D’Amato, Stefano Ferraro, Marco Minicucci, Roberto Gunnella, Andrea Di Cicco. Reduced Graphene Oxide/TiO2 Nanocomposite: From Synthesis to Characterization for Efficient Visible Light Photocatalytic Applications. Catalysts. 2018; 8 (12):598.
Chicago/Turabian StyleElena Rommozzi; Marco Zannotti; Rita Giovannetti; Chiara Anna D’Amato; Stefano Ferraro; Marco Minicucci; Roberto Gunnella; Andrea Di Cicco. 2018. "Reduced Graphene Oxide/TiO2 Nanocomposite: From Synthesis to Characterization for Efficient Visible Light Photocatalytic Applications." Catalysts 8, no. 12: 598.
The effect of surface modification using ascorbic acid as a surface modifier of nano-TiO2 heterogeneous photocatalyst was studied. The preparation of supported photocatalyst was made by a specific paste containing ascorbic acid modified TiO2 nanoparticles used to cover Polypropylene as a support material. The obtained heterogeneous photocatalyst was thoroughly characterized (scanning electron microscope (SEM), RAMAN, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and Diffuse Reflectance Spectra (DRS) and successfully applied in the visible light photodegradation of Alizarin Red S in water solutions. In particular, this new supported TiO2 photocatalyst showed a change in the adsorption mechanism of dye with respect to that of only TiO2 due to the surface properties. In addition, an improvement of photocatalytic performances in the visible light photodegration was obtained, showing a strict correlation between efficiency and energy band gap values, evidencing the favorable surface modification of TiO2 nanoparticles.
Chiara Anna D’Amato; Rita Giovannetti; Marco Zannotti; Elena Rommozzi; Marco Minicucci; Roberto Gunnella; Andrea Di Cicco. Band Gap Implications on Nano-TiO2 Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst. Nanomaterials 2018, 8, 599 .
AMA StyleChiara Anna D’Amato, Rita Giovannetti, Marco Zannotti, Elena Rommozzi, Marco Minicucci, Roberto Gunnella, Andrea Di Cicco. Band Gap Implications on Nano-TiO2 Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst. Nanomaterials. 2018; 8 (8):599.
Chicago/Turabian StyleChiara Anna D’Amato; Rita Giovannetti; Marco Zannotti; Elena Rommozzi; Marco Minicucci; Roberto Gunnella; Andrea Di Cicco. 2018. "Band Gap Implications on Nano-TiO2 Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst." Nanomaterials 8, no. 8: 599.
A new approach to obtain a heterogeneous photocatalytic material with gold nanoparticles and TiO2 semiconductor was performed exploiting the reducing ability of acetylacetone, a chemical present in the TiO2 paste formulation. Gold / TiO2 heterogeneous catalyst supported on polypropylene [[email protected]]A was prepared; composition, structure and morphology of this new material were defined by using UV–Vis spectroscopy, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), X-Ray diffraction (XRD), X-Ray Fluorescence (XRF), Raman Spectroscopy, Photoluminescence and Diffuse Reflectance Spectroscopy. The new material was tested in the photocatalytic degradation of Alizarin Red S in water solution, as target pollutant, under visible light and correlated with structural and spectroscopic characterizations. [[email protected]]A showed higher photocatalytic activity respect to pure [[email protected]]A with an improvement of photodegradation kinetic. The best performance was obtained using [[email protected]]A sample with 0.006 wt.% of Au and the photocatalytic improvement was correlated with the band gap energy decrease of photocatalyst.
C.A. D'Amato; R. Giovannetti; M. Zannotti; Elena Rommozzi; S. Ferraro; C. Seghetti; M. Minicucci; Roberto Gunnella; A. Di Cicco. Enhancement of visible-light photoactivity by polypropylene coated plasmonic Au/TiO2 for dye degradation in water solution. Applied Surface Science 2018, 441, 575 -587.
AMA StyleC.A. D'Amato, R. Giovannetti, M. Zannotti, Elena Rommozzi, S. Ferraro, C. Seghetti, M. Minicucci, Roberto Gunnella, A. Di Cicco. Enhancement of visible-light photoactivity by polypropylene coated plasmonic Au/TiO2 for dye degradation in water solution. Applied Surface Science. 2018; 441 ():575-587.
Chicago/Turabian StyleC.A. D'Amato; R. Giovannetti; M. Zannotti; Elena Rommozzi; S. Ferraro; C. Seghetti; M. Minicucci; Roberto Gunnella; A. Di Cicco. 2018. "Enhancement of visible-light photoactivity by polypropylene coated plasmonic Au/TiO2 for dye degradation in water solution." Applied Surface Science 441, no. : 575-587.
The effect of pH change on 5,10,15,20-Tetrakis(4-hydroxyphenyl)-21H,23H-porphine (THPP) with its aggregation as function of water-ethanol mixture was studied with UV-vis, fluorescence, Raman and computational analysis. In neutral pH, THPP was present as free-base and, increasing the water amount, aggregation occurred with the formation of H- and J-aggregates. The aggregation constant and the concentration of dimers were calculated, other information about the dimer aggregation were evaluated by computational study. In acidic pH, by the insertions of two hydrogens in the porphyrin rings, the porphyrin changed its geometry with a ring deformation confirmed by red-shifted spectrum and quenching in fluorescence; at this low pH, increasing the water amount, the acidic form (THPPH) resulted more stable due to a polar environment with stronger interaction by hydrogen bonding. In basic pH, reached by NHOH, THPP porphyrin was able to react with alkali metals in order to form sitting-atop complex (MTHPP) confirmed by the typical absorption spectrum of metallo-porphyrin, Raman spectroscopy and by computational analysis.
Marco Zannotti; Rita Giovannetti; Babak Minofar; David Reha; Lydie Plackova; Chiara A. D'Amato; Elena Rommozzi; Hanna V. Dudko; Nuerguli Kari; Marco Minicucci. Aggregation and metal-complexation behaviour of THPP porphyrin in ethanol/water solutions as function of pH. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 2018, 193, 235 -248.
AMA StyleMarco Zannotti, Rita Giovannetti, Babak Minofar, David Reha, Lydie Plackova, Chiara A. D'Amato, Elena Rommozzi, Hanna V. Dudko, Nuerguli Kari, Marco Minicucci. Aggregation and metal-complexation behaviour of THPP porphyrin in ethanol/water solutions as function of pH. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. 2018; 193 ():235-248.
Chicago/Turabian StyleMarco Zannotti; Rita Giovannetti; Babak Minofar; David Reha; Lydie Plackova; Chiara A. D'Amato; Elena Rommozzi; Hanna V. Dudko; Nuerguli Kari; Marco Minicucci. 2018. "Aggregation and metal-complexation behaviour of THPP porphyrin in ethanol/water solutions as function of pH." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 193, no. : 235-248.
Synthetic dyes are widely used in textile, paper, food, cosmetic, and pharmaceutical industries. During industrial processes, some of these dyes are released into the wastewater and their successive release into rivers and lakes produces serious environmental problems. TiO2 is one of the most widely studied and used photocatalysts for environmental remediation. However, it is mainly active under UV-light irradiation due to its band gap of 3.2 eV, while it shows low efficiency under the visible light spectrum. Regarding the exploration of TiO2 activation in the visible light region of the total solar spectrum, the incorporation of carbon nanomaterials, such as graphene, in order to form carbon-TiO2 composites is a promising area. Graphene, in fact, has a large surface area which makes it a good adsorbent for organic pollutants removal through the combination of electrostatic attraction and π-π interaction. Furthermore, it has a high electron mobility and therefore it reduces the electron-hole pair recombination, improving the photocatalytic activity of the semiconductor. In recent years, there was an increasing interest in the preparation of graphene-based TiO2 photocatalysts. The present short review describes the recent advances in TiO2 photocatalyst coupling with graphene materials with the aim of extending the light absorption of TiO2 from UV wavelengths into the visible region, focusing on recent progress in the design and applications in the photocatalytic degradation of synthetic dyes.
Rita Giovannetti; Elena Rommozzi; Marco Zannotti; Chiara Anna D’Amato. Recent Advances in Graphene Based TiO2 Nanocomposites (GTiO2Ns) for Photocatalytic Degradation of Synthetic Dyes. Catalysts 2017, 7, 305 .
AMA StyleRita Giovannetti, Elena Rommozzi, Marco Zannotti, Chiara Anna D’Amato. Recent Advances in Graphene Based TiO2 Nanocomposites (GTiO2Ns) for Photocatalytic Degradation of Synthetic Dyes. Catalysts. 2017; 7 (10):305.
Chicago/Turabian StyleRita Giovannetti; Elena Rommozzi; Marco Zannotti; Chiara Anna D’Amato. 2017. "Recent Advances in Graphene Based TiO2 Nanocomposites (GTiO2Ns) for Photocatalytic Degradation of Synthetic Dyes." Catalysts 7, no. 10: 305.
The geochemistry of thermal spring waters in the Acquasanta Terme area, located on the Adriatic side of central Italy, has been investigated in order to characterize the geothermal feeding system. The springs discharge more than 100 L/s at temperature ranging between 20 and 30 °C. They occur in a tectonic window of Mesozoic limestones in the central sector of the Acquasanta anticline within the Laga foredeep Basin. Chemical and isotopic compositions of thermal and cold fluids were investigated, most of them monitored for one year, in order to understand the thermal fluid circulation paths. The chemistry of the major elements defines the existence of Na–Cl and Ca–Cl–SO4 2- hot discharging waters and permits the characterization of the thermal end-member hosted in carbonate-dominated reservoir (Burano Anhydrites Fm–Calcare Massiccio Fm). This deep fluid is well represented by the sample T1 and shows high temperature and electrical conductivity (EC), very stable over time, and not affected by mixing phenomena. This is also confirmed by tritium results (0 T.U.). Close to the surface at different depth, such water undergoes mixing or dilution processes with HCO3 − rich freshwaters, driven by the complex structural setting of the area and by diffuse karst caves. This is identified as the main reason for observed compositional variations of sampled springs, and three areas affected by different mixing phenomena have been defined at the surface. The concentrations of SO4 2− and H2S suggest redox processes affecting sulfur after interaction with evaporitic formations, identified with the Burano Anhydrites, at the base of the Umbria–Marche sedimentary sequence (∼3500-m-deep). Contribution from this reservoir is also supported by characteristic Sr isotope signature. δ18O and δD values indicate a meteoric origin of the thermal waters and allow estimation of an average infiltration altitude ranging between 1500 and 1700 m a.s.l. This datum, supported by structural data, suggests the Laga Mountains as the recharge area of the system. Reservoir temperature inferred by SO4 2−–HCO3 −–F, Ca/Mg and SO4 2−/F geothermometers is about 80 °C, consistent with the geothermal gradient of the foredeep basin, and deserving further investigations for potential economic implications about this low-enthalpy geothermal area
Alessandro Fusari; Michael R. Carroll; Stefano Ferraro; Rita Giovannetti; Geoffrey Giudetti; Chiara Invernizzi; Mario Mussi; Maddalena Pennisi. Circulation path of thermal waters within the Laga foredeep basin inferred from chemical and isotopic (δ18O, δD, 3H, 87Sr/86Sr) data. Applied Geochemistry 2017, 78, 23 -34.
AMA StyleAlessandro Fusari, Michael R. Carroll, Stefano Ferraro, Rita Giovannetti, Geoffrey Giudetti, Chiara Invernizzi, Mario Mussi, Maddalena Pennisi. Circulation path of thermal waters within the Laga foredeep basin inferred from chemical and isotopic (δ18O, δD, 3H, 87Sr/86Sr) data. Applied Geochemistry. 2017; 78 ():23-34.
Chicago/Turabian StyleAlessandro Fusari; Michael R. Carroll; Stefano Ferraro; Rita Giovannetti; Geoffrey Giudetti; Chiara Invernizzi; Mario Mussi; Maddalena Pennisi. 2017. "Circulation path of thermal waters within the Laga foredeep basin inferred from chemical and isotopic (δ18O, δD, 3H, 87Sr/86Sr) data." Applied Geochemistry 78, no. : 23-34.
Novel composite materials PEn (n = 1–9) have been prepared by an easily up-scalable embedding procedure of three different families of Ag(I) acylpyrazolonato complexes in polyethylene (PE) matrix. In details, PE1–PE3 composites contain polynuclear [Ag(QR)]n complexes, PE4–PE6 contain mononuclear [Ag(QR)(L)m] complexes and PE7–PE9 are loaded with mononuclear [Ag(QR) (PPh3)2] complexes, respectively (where L = 1-methylimidazole or 2-ethylimidazole, m = 1 or 2, and HQR = 1-phenyl-3-methyl-4-RC(═O)-5-pyrazolone, where in detail HQfb, R = −CF2CF2CF3; HQcy, R = −cyclo-C6H11; HQbe, R = −C(H)═C(CH3)2). The PEn composites, prepared by using a 1:1000 w/w silver additive/polyethylene ratio, have been characterized in bulk by IR spectroscopy and TGA analyses, which confirmed that the properties of polyethylene matrix are essentially unchanged. AFM, SEM, and EDX surface techniques show that silver additives form agglomerates with dimensions 10–100 μm on the polyethylene surface, with a slight increment of surface roughness of pristine plastic within 50 nm. However, the elastic properties of the composites are essentially the same of PE. The antibacterial activity of all composites has been tested against three bacterial strains (E. coli, P. aeruginosa and S. aureus) and results show that two classes of composites, PE1–PE3 and PE4–PE6, display high and persistent bactericidal and bacteriostatic activity, comparable to PE embedded with AgNO3. By contrast, composites PE7–PE9 exhibit a reduced antibacterial action. Contact and release tests in several conditions for specific migration of Ag+ from plastics, indicate a very limited but time persistent release of silver ions from PE1–PE6 composites, thus suggesting that they are potential antibacterial materials for future applications. Instead, PE7–PE9 almost do not release silver, only trace levels of silver ions being detected, in accordance with their reduced antibacterial action. None of the composites is toxic against higher organisms, as confirmed by D. magna test of ecotoxicity.
Fabio Marchetti; Jessica Palmucci; Claudio Pettinari; Riccardo Pettinari; Mirko Marangoni; Stefano Ferraro; Rita Giovannetti; Stefania Scuri; Iolanda Grappasonni; Mario Cocchioni; Francisco Jose Maldonado Hódar; Roberto Gunnella. Preparation of Polyethylene Composites Containing Silver(I) Acylpyrazolonato Additives and SAR Investigation of their Antibacterial Activity. ACS Applied Materials & Interfaces 2016, 8, 29676 -29687.
AMA StyleFabio Marchetti, Jessica Palmucci, Claudio Pettinari, Riccardo Pettinari, Mirko Marangoni, Stefano Ferraro, Rita Giovannetti, Stefania Scuri, Iolanda Grappasonni, Mario Cocchioni, Francisco Jose Maldonado Hódar, Roberto Gunnella. Preparation of Polyethylene Composites Containing Silver(I) Acylpyrazolonato Additives and SAR Investigation of their Antibacterial Activity. ACS Applied Materials & Interfaces. 2016; 8 (43):29676-29687.
Chicago/Turabian StyleFabio Marchetti; Jessica Palmucci; Claudio Pettinari; Riccardo Pettinari; Mirko Marangoni; Stefano Ferraro; Rita Giovannetti; Stefania Scuri; Iolanda Grappasonni; Mario Cocchioni; Francisco Jose Maldonado Hódar; Roberto Gunnella. 2016. "Preparation of Polyethylene Composites Containing Silver(I) Acylpyrazolonato Additives and SAR Investigation of their Antibacterial Activity." ACS Applied Materials & Interfaces 8, no. 43: 29676-29687.
Graphene dispersion (GR) was prepared by liquid-phase sonication of graphite and evaluated by XRD, DLS and UV-Vis analysis. It was used to prepare [email protected]–TiO 2 , showing positive effects on ARS photodegradation under visible light irradiation. The aim of this study was the preparation of a graphene/TiO 2 heterogeneous catalyst supported on polypropylene for visible light photocatalysis. Aqueous graphene dispersions were prepared by liquid-phase exfoliation of graphite in the presence of a non-ionic surfactant, Triton X-100. The obtained graphene dispersion was characterized by X-ray diffraction, dynamic light scattering and UV-Visible spectroscopy and was subsequently used for the preparation of graphene/TiO 2 photocatalyst. As-prepared photocatalysts were tested for the photocatalytic degradation of a refractory dye, Alizarin Red S, in water solutions as target pollutant. Graphene/TiO 2 nanocomposites showed higher adsorption of Alizarin Red S on the catalyst surface and higher photocatalytic activity for its degradation under visible light irradiation, in respect to those obtained with pure TiO 2 .
Rita Giovannetti; Elena Rommozzi; Marco Zannotti; Chiara Anna D'amato; S. Ferraro; Marco Cespi; G. Bonacucina; M. Minicucci; A. Di Cicco. Exfoliation of graphite into graphene in aqueous solution: an application as graphene/TiO 2 nanocomposite to improve visible light photocatalytic activity. RSC Advances 2016, 6, 93048 -93055.
AMA StyleRita Giovannetti, Elena Rommozzi, Marco Zannotti, Chiara Anna D'amato, S. Ferraro, Marco Cespi, G. Bonacucina, M. Minicucci, A. Di Cicco. Exfoliation of graphite into graphene in aqueous solution: an application as graphene/TiO 2 nanocomposite to improve visible light photocatalytic activity. RSC Advances. 2016; 6 (95):93048-93055.
Chicago/Turabian StyleRita Giovannetti; Elena Rommozzi; Marco Zannotti; Chiara Anna D'amato; S. Ferraro; Marco Cespi; G. Bonacucina; M. Minicucci; A. Di Cicco. 2016. "Exfoliation of graphite into graphene in aqueous solution: an application as graphene/TiO 2 nanocomposite to improve visible light photocatalytic activity." RSC Advances 6, no. 95: 93048-93055.
The simultaneous adsorption and visible light photodegradation of Alizarin Red S in water solutions were studied in real time mode by using nano-TiO2, such as Anatase and Aeroxide P-25, supported on polypropylene strips. Kinetic results of the overall process were compared with those obtained from separated steps of adsorption and photodegradation previously studied; kinetic advantages were evidenced with the simultaneous approach. From the study of different dye concentrations, a kinetic model has been proposed which describes the overall process. This model considered two consecutive processes: The adsorption of dye on TiO2 surface and its photodegradation. The obtained results were in good agreement with experimental data and can predict the profiles of free dye, dye adsorbed on TiO2 and photoproduct concentrations during the total process.
Rita Giovannetti; Elena Rommozzi; Chiara Anna D’Amato; Marco Zannotti. Kinetic Model for Simultaneous Adsorption/Photodegradation Process of Alizarin Red S in Water Solution by Nano-TiO2 under Visible Light. Catalysts 2016, 6, 84 .
AMA StyleRita Giovannetti, Elena Rommozzi, Chiara Anna D’Amato, Marco Zannotti. Kinetic Model for Simultaneous Adsorption/Photodegradation Process of Alizarin Red S in Water Solution by Nano-TiO2 under Visible Light. Catalysts. 2016; 6 (6):84.
Chicago/Turabian StyleRita Giovannetti; Elena Rommozzi; Chiara Anna D’Amato; Marco Zannotti. 2016. "Kinetic Model for Simultaneous Adsorption/Photodegradation Process of Alizarin Red S in Water Solution by Nano-TiO2 under Visible Light." Catalysts 6, no. 6: 84.