1
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Minev N, Buchkov K, Todorova N, Todorov R, Videva V, Stefanova M, Rafailov P, Karashanova D, Dikov H, Strijkova V, Trapalis C, Lin SH, Dimitrov D, Marinova V. Synthesis of 2D PtSe 2 Nanolayers on Glass Substrates and Their Integration in Near-Infrared Light Shutters. ACS Omega 2024; 9:14874-14886. [PMID: 38585138 PMCID: PMC10993254 DOI: 10.1021/acsomega.3c08235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 03/02/2024] [Accepted: 03/06/2024] [Indexed: 04/09/2024]
Abstract
PtSe2 has asserted its key role among the emerging 2D transition metal dichalcogenides, however, its simplified growth process with controlled number of layers, high crystalline quality, and on inexpensive substrates is still challenging. Here, we report the synthesis details of PtSe2 layers on soda lime glass substrates by selenization of predeposited Pt layers using the thermally assisted conversion method at atmospheric pressure. PtSe2 syntheses are confirmed by X-ray photoelectron spectroscopy and Raman analysis. The layers were further investigated with transmission electron microscopy and optical ellipsometry, revealing the thickness and its dependence on the metal precursor sputtering time. Finally, the integration of PtSe2 as transparent conductive layers in polymer-dispersed liquid crystal structures operating as near-infrared light shutters is demonstrated and device performance is discussed. The proposed simple and inexpensive synthesis approach opens up new directions toward PtSe2 potential technological applications, including ITO-free optoelectronics.
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Affiliation(s)
- Nikolay Minev
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
| | - Krastyo Buchkov
- Institute
of Solid-State Physics, Bulgarian Academy
of Sciences, 72, Tzarigradsko
Chaussee Blvd, 1784 Sofia, Bulgaria
| | - Nadia Todorova
- Institute
of Nanoscience and Nanotechnology, National
Centre for Scientific Research “Demokritos” 15341 Agia Paraskevi, Greece
| | - Rosen Todorov
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
| | - Vladimira Videva
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
- Faculty
of Chemistry and Pharmacy, Sofia University, 1 James Bourchier Blvd., 1164 Sofia, Bulgaria
| | - Maria Stefanova
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
| | - Peter Rafailov
- Institute
of Solid-State Physics, Bulgarian Academy
of Sciences, 72, Tzarigradsko
Chaussee Blvd, 1784 Sofia, Bulgaria
| | - Daniela Karashanova
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
| | - Hristosko Dikov
- Central
Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia, Bulgaria
| | - Velichka Strijkova
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
| | - Christos Trapalis
- Institute
of Nanoscience and Nanotechnology, National
Centre for Scientific Research “Demokritos” 15341 Agia Paraskevi, Greece
| | - Shiuan Huei Lin
- Department
of Electrophysics, National Yang Ming Chiao
Tung University, 30010 Hsinchu, Taiwan
| | - Dimitre Dimitrov
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
- Institute
of Solid-State Physics, Bulgarian Academy
of Sciences, 72, Tzarigradsko
Chaussee Blvd, 1784 Sofia, Bulgaria
| | - Vera Marinova
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bontchev Str. 109, 1113 Sofia, Bulgaria
- Department
of Electrophysics, National Yang Ming Chiao
Tung University, 30010 Hsinchu, Taiwan
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2
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Bakola V, Kotrotsiou O, Ntziouni A, Dragatogiannis D, Plakantonaki N, Trapalis C, Charitidis C, Kiparissides C. Development of Composite Nanostructured Electrodes for Water Desalination via Membrane Capacitive Deionization. Macromol Rapid Commun 2024; 45:e2300640. [PMID: 38184786 DOI: 10.1002/marc.202300640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/22/2023] [Indexed: 01/08/2024]
Abstract
Novel two-layer nanostructured electrodes are successfully prepared for their application in membrane capacitive deionization (MCDI) processes. Nanostructured carbonaceous materials such as graphene oxide (GO) and carbon nanotubes (CNTs), as well as activated carbon (AC) are dispersed in a solution of poly(vinyl alcohol) (PVA), mixed with polyacrylic acid (PAA) or polydimethyldiallylammonium chloride (PDMDAAC), and subsequently cast on the top surface of an AC-based modified graphite electrode to form a thin composite layer that is cross-linked with glutaraldehyde (GA). Cyclic voltammetry (CV) is performed to investigate the electrochemical properties of the composite electrodes and desalination experiments are conducted in batch mode using a MCDI unit cell to investigate the effects of i) the nanostructured carbonaceous material, ii) its concentration in the polymer blend, and iii) the molecular weight of the polymers on the desalination efficiency of the system. Comparative studies with commercial membranes are performed proving that the composite nanostructured electrodes are more efficient in salt removal. The improved performance of the composite electrodes is attributed to the ion exchange properties of the selected polymers and the increased specific capacitance of the nanostructured carbonaceous materials. This research paves the way for wider application of MCDI in water desalination.
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Affiliation(s)
- Veroniki Bakola
- Centre for Research and Technology Hellas (CERTH), Chemical Process and Energy Resources Institute (CPERI), 6th km Charilaou-Thermi Rd, Thermi, Thessaloniki, 57001, Greece
- Aristotle University of Thessaloniki (AUTH), Department of Chemical Engineering, University Campus, Thessaloniki, 54124, Greece
| | - Olympia Kotrotsiou
- Centre for Research and Technology Hellas (CERTH), Chemical Process and Energy Resources Institute (CPERI), 6th km Charilaou-Thermi Rd, Thermi, Thessaloniki, 57001, Greece
| | - Afroditi Ntziouni
- Research Unit of Advanced, Composite, Nano-Materials and Nanotechnology, School of Chemical Engineering, National Technical University of Athens, 9 Heroon Polytechneiou Street, Zografos, Athens, 15780, Greece
| | - Dimitris Dragatogiannis
- DELTA-MPIS, Technological Park of Lefkippos, Neapoleos and Patriarchou Grigoriou St, Agia Paraskevi, Attikis, Athens, 15341, Greece
| | - Niki Plakantonaki
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Agia Paraskevi, Attikis, Athens, 15341, Greece
| | - Christos Trapalis
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Agia Paraskevi, Attikis, Athens, 15341, Greece
| | - Costas Charitidis
- Research Unit of Advanced, Composite, Nano-Materials and Nanotechnology, School of Chemical Engineering, National Technical University of Athens, 9 Heroon Polytechneiou Street, Zografos, Athens, 15780, Greece
| | - Costas Kiparissides
- Centre for Research and Technology Hellas (CERTH), Chemical Process and Energy Resources Institute (CPERI), 6th km Charilaou-Thermi Rd, Thermi, Thessaloniki, 57001, Greece
- Aristotle University of Thessaloniki (AUTH), Department of Chemical Engineering, University Campus, Thessaloniki, 54124, Greece
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3
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Giannakopoulou T, Todorova N, Plakantonaki N, Vagenas M, Sakellis E, Papargyriou D, Katsiotis M, Trapalis C. CO 2-Derived Nanocarbons with Controlled Morphology and High Specific Capacitance. ACS Omega 2023; 8:29500-29511. [PMID: 37599958 PMCID: PMC10433508 DOI: 10.1021/acsomega.3c03207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 07/07/2023] [Indexed: 08/22/2023]
Abstract
The conversion of CO2 to nanocarbons addresses a dual goal of harmful CO2 elimination from the atmosphere along with the production of valuable nanocarbon materials. In the present study, a simple one-step metallothermic CO2 reduction to nanocarbons was performed at 675 °C with the usage of a Mg reductant. The latter was employed alone and in its mixture with ferrocene, which was found to control the morphology of the produced nanocarbons. Scanning electron microscopy (SEM) analysis reveals a gradual increase in the amount of nanoparticles with different shapes and a decrease in tubular nanostructures with the increase of ferrocene content in the mixture. A possible mechanism for such morphological alterations is discussed. Transmission electron microscopy (TEM) analysis elucidates that the nanotubes and nanoparticles gain mainly amorphous structures, while sheet- and cloud-like morphologies also present in the materials possess significantly improved crystallinity. As a result, the overall crystallinity was preserved constant for all of the samples, which was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. Finally, electrochemical tests demonstrated that the prepared nanocarbons retained high specific capacitance values in the range of 200-310 F/g (at 0.1 V/s), which can be explained by the measured high specific surface area (650-810 m2/g), total pore volume (1.20-1.55 cm3/g), and the degree of crystallinity. The obtained results demonstrate the suitability of ferrocene for managing the nanocarbons' morphology and open perspectives for the preparation of efficient "green" nanocarbon materials for energy storage applications and beyond.
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Affiliation(s)
- Tatiana Giannakopoulou
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Nadia Todorova
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Niki Plakantonaki
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Michail Vagenas
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Elias Sakellis
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | | | - Marios Katsiotis
- Group
Innovation & Technology, TITAN Cement
S.A., 11143 Athens, Greece
| | - Christos Trapalis
- Institute
of Nanoscience and Nanotechnology, National
Center for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
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4
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Antonopoulou M, Bika P, Papailias I, Zervou SK, Vrettou A, Efthimiou I, Mitrikas G, Ioannidis N, Trapalis C, Dallas P, Vlastos D, Hiskia A. Photocatalytic degradation of organic micropollutants under UV-A and visible light irradiation by exfoliated g-C 3N 4 catalysts. Sci Total Environ 2023:164218. [PMID: 37211132 DOI: 10.1016/j.scitotenv.2023.164218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/02/2023] [Accepted: 05/13/2023] [Indexed: 05/23/2023]
Abstract
In the present study, the photocatalytic performance of exfoliated graphitic carbon nitride (g-C3N4) catalysts, with enhanced properties and response in UV and visible light irradiation, was evaluated for the removal of selected contaminants i.e., diuron, bisphenol A and ethyl paraben. Commercial TiO2 Degussa P25 was also used as a reference photocatalyst. g-C3N4 catalysts demonstrated good photocatalytic activity which in some cases is comparable to TiO2 Degussa P25 leading to high removal percentages of the studied micropollutants under UV-A light irradiation. In contrast to TiO2 Degussa P25, g-C3N4 catalysts were also able to degrade the studied micropollutants under visible light irradiation. For all the studied g-C3N4 under both UV-A and visible light irradiation, the overall degradation rate decreases in the order of bisphenol A > diuron > ethyl paraben. Among the studied g-C3N4, the chemically exfoliated catalyst (g-C3N4-CHEM) showed superior photocatalytic activity under UV-A light irradiation due to its enhanced characteristics, such as pore volume and specific surface area and ~ 82.0 in 6 min, ~75.7 in 15 min and ~ 96.3 % in 40 min removals were achieved for BPA, DIU and EP, respectively. Under visible light irradiation, the thermally exfoliated catalyst (g-C3N4-THERM) demonstrated the best photocatalytic performance and the degradation ranged from ~29.5 to 59.4 % after 120 min. EPR data revealed that the three g-C3N4 semiconductors generate mainly O2•-, whereas TiO2 generates both HO• and O2•-, the latter only under UV-A light irradiation. Nevertheless, the indirect formation of HO• in the case of g-C3N4 should also be considered. Hydroxylation, oxidation, dealkylation, dechlorination and ring opening were the main degradation pathways. The process proceeded without significant alterations in toxicity levels. Based on the results, heterogeneous photocatalysis using g-C3N4 catalysts is a promising method for the removal of organic micropollutants without the formation of harmful transformation products.
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Affiliation(s)
- Maria Antonopoulou
- Department of Sustainable Agriculture, University of Patras, 30100, Agrinio, Greece.
| | - Panagiota Bika
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Ilias Papailias
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Sevasti-Kiriaki Zervou
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Androniki Vrettou
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Ioanna Efthimiou
- Department of Sustainable Agriculture, University of Patras, 30100, Agrinio, Greece
| | - George Mitrikas
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Nikolaos Ioannidis
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Christos Trapalis
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Panagiotis Dallas
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
| | - Dimitris Vlastos
- Department of Biology, Section of Genetics Cell Biology and Development, University of Patras, 26500 Patras, Greece
| | - Anastasia Hiskia
- Institute of Nanoscience & Nanotechnology, NCSR "Demokritos", Patr. Gregoriou E' & 27 Neapoleos Str, 15341 Agia Paraskevi, Athens, Greece
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5
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Mavrikos A, Papoulis D, Todorova N, Papailias I, Trapalis C, Panagiotaras D, Chalkias D, Stathatos E, Gianni E, Somalakidi K, Sygkridou D, Komarneni S. Synthesis of Zn/Cu metal ion modified natural palygorskite clay – TiO2 nanocomposites for the photocatalytic outdoor and indoor air purification. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113568] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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6
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Athanasoulia I, Giachalis K, Korres D, Todorova N, Giannakopoulou T, Tarantili PA, Trapalis C. Study of thermomechanical, structural and antibacterial properties of poly(lactic acid) reinforced with graphene oxide nanoparticles via melt mixing. POLYM INT 2020. [DOI: 10.1002/pi.6054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ioanna‐Georgia Athanasoulia
- Polymer Technology Laboratory, School of Chemical Engineering National Technical University of Athens Athens Greece
| | - Konstantinos Giachalis
- Polymer Technology Laboratory, School of Chemical Engineering National Technical University of Athens Athens Greece
| | - Dimitrios Korres
- Polymer Technology Laboratory, School of Chemical Engineering National Technical University of Athens Athens Greece
| | - Nadia Todorova
- Institute for Nanoscience and Nanotechnology National Center for Scientific Research ‘Demokritos’ Athens Greece
| | - Tatiana Giannakopoulou
- Institute for Nanoscience and Nanotechnology National Center for Scientific Research ‘Demokritos’ Athens Greece
| | - Petroula A Tarantili
- Polymer Technology Laboratory, School of Chemical Engineering National Technical University of Athens Athens Greece
| | - Christos Trapalis
- Institute for Nanoscience and Nanotechnology National Center for Scientific Research ‘Demokritos’ Athens Greece
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Yang Y, Tang Y, Jiang H, Chen Y, Wan P, Fan M, Zhang R, Ullah S, Pan L, Zou JJ, Lao M, Sun W, Yang C, Zheng G, Peng Q, Wang T, Luo Y, Sun X, Konev AS, Levin OV, Lianos P, Zhuofeng H, Shen Z, Zhao Q, Wang Y, Todorova N, Trapalis C, Sheridan MV, Wang H, Zhang L, Sun S, Wang W, Ma J. 2020 Roadmap on gas-involved photo- and electro- catalysis. CHINESE CHEM LETT 2019. [DOI: 10.1016/j.cclet.2019.10.041] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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8
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Chaitoglou S, Giannakopoulou T, Tsoutsou D, Vavouliotis A, Trapalis C, Dimoulas A. Direct versus reverse vertical two-dimensional Mo 2C/graphene heterostructures for enhanced hydrogen evolution reaction electrocatalysis. Nanotechnology 2019; 30:415404. [PMID: 31295736 DOI: 10.1088/1361-6528/ab3155] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Mo2C/graphene heterostructures prepared by chemical vapor deposition have demonstrated excellent electrocatalytic activity in a hydrogen evolution reaction (HER). This is attributed to the high catalytic activity of Mo2C while the high electrical conductivity of graphene facilitates charge transfer. In the as-grown direct vertical order, graphene is placed above the Mo2C film. This reduces the catalytic activity of the heterostructure, since graphene in chemically inert. Here, a simple transfer method is proposed that results in the reverse order deposition of the heterostructure on the electrode. This method places graphene at the interface between Mo2C and the electrode, enhancing charge transfer between them, which results in an overpotential of 440 mV at 10 mA cm-2 and corresponds to ∼65 mV overpotential reduction as compared to the direct heterostructure. At the same time, when a direct Cu/Mo2C/graphene junction with a Cu catalyst substrate is used as a working electrode, the improvement of the heterostructure HER activity is observed which is manifested in an overpotential of 275 mV at 10 mA cm-2 with a correspondent ∼230 mV reduction. All above performances are accompanied with excellent endurance.
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Affiliation(s)
- Stefanos Chaitoglou
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research 'DEMOKRITOS', 15310, Athens, Greece
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9
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Chaitoglou S, Giannakopoulou T, Speliotis T, Vavouliotis A, Trapalis C, Dimoulas A. Mo 2C/graphene heterostructures: low temperature chemical vapor deposition on liquid bimetallic Sn-Cu and hydrogen evolution reaction electrocatalytic properties. Nanotechnology 2019; 30:125401. [PMID: 30566921 DOI: 10.1088/1361-6528/aaf9e8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Thin 2D Mo2C/graphene vertical heterostructures have attracted significant attention due to their potential application as electrodes in the hydrogen evolution reaction (HER) and energy storage. A common drawback in the chemical vapor deposition synthesis of these structures is the demand for high temperature growth, which should be higher than the melting temperature of the metal catalyst. The most common metallic catalyst is Cu, which has a melting temperature of 1084 °C. Here, we report the growth of thin, ∼200 nm in thickness, semitransparent micrometer-sized Mo2C domains and Mo2C/graphene heterostructures at lower temperatures using liquid Sn-Cu alloys. No Sn-associated defects are observed, making the alloy an appealing growth substrate. Raman spectroscopy reveals the vertical interaction between graphene and Mo2C, as shown by the variation in the strain of the graphene film. The results demonstrate the capability to grow continuous nanometer-thin Mo2C films at temperatures as low as 880 °C, without sacrificing the growth rate. Mo2C films are proven to be efficient electrocatalysts for the HER. Moreover, we demonstrate the beneficial role of graphene overgrown on Mo2C in reducing the HER overpotential values, which is attributed to more efficient charge transfer kinetics, compared to pure Mo2C films.
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Affiliation(s)
- Stefanos Chaitoglou
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research 'DEMOKRITOS', 15310, Athens, Greece
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10
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Vermisoglou EC, Giannakopoulou T, Todorova N, Vaimakis T, Boukos N, Petridis D, Trapalis C. 2-Dimensional Clay/Reduced Graphene Oxide Ordered Heterostructures Dispersible in Water via a One-Step Hydrothermal Route. J Nanosci Nanotechnol 2018; 18:4684-4691. [PMID: 29442646 DOI: 10.1166/jnn.2018.15334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A facile and green method for trapping the hydrophobic reduced graphene oxide between the hydrophilic Kunipia F layers in order to attain stable aqueous dispersions of reduced graphene oxide is described. Initially stable aqueous dispersions of hydrophilic clay intercalated with hydrophilic graphene oxide sheets were formed providing well-organized heterostructures, as it was revealed by scanning electron microscopy images. These structures were preserved in the product obtained after hydrothermal treatment where the hydrophilic graphene oxide was converted to hydrophobic reduced graphene oxide. Ultraviolet measurements revealed the aforementioned conversion which was accompanied by a characteristic change in color from yellow-brown to black in the corresponding aqueous dispersions of these hybrids before and after hydrothermal treatment. The stability of these homogeneous dispersions was confirmed by Zeta Potential measurements implying interactions both in cases of graphene oxide and reduced graphene oxide with clay sheets that made feasible the effective interstratification of graphene-clay layered materials. In these stable dispersions chemistry in aqueous environment could be fully utilized making possible their incorporation e.g., as fillers to hydrophilic polymeric matrices extending thus the limits of application.
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Affiliation(s)
- E C Vermisoglou
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
| | - T Giannakopoulou
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
| | - N Todorova
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
| | - T Vaimakis
- Department of Chemistry, University of Ioannina, P.O. Box 1186, Ioannina, Greece
| | - N Boukos
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
| | - D Petridis
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
| | - C Trapalis
- Institute of Nanoscience and Nanotechnology (INN), NCSR "Demokritos", 15343, Agia Paraskevi, Attikis, Greece
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11
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Triantou M, Todorova N, Giannakopoulou T, Vaimakis T, Trapalis C. Physical Properties of Photo-Aged Graphene/Polypropylene Nanocomposites. J Nanosci Nanotechnol 2018; 18:5033-5041. [PMID: 29442690 DOI: 10.1166/jnn.2018.15335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the present research, graphene nanoplatelets/polypropylene (GNP/PP) nanocomposites were prepared by melt mixing and were subjected to accelerated ageing. The effect of graphene on the morphology and physical properties of aged GNP/PP nanocomposites was investigated. The incorporation of graphene to non-aged PP matrix led to changes in its crystal conformation, decreased the ultraviolet-visible (UV-Vis) transmittance and tensile strain and increased the elastic modulus. The ageing of non-reinforced PP increased the β-phase of PP and caused the formation of cracks on its surface, while voids were observed in its cross-section. The aged PP was also characterized by significantly lower UV-Vis transmittance, thermal stability and tensile strain, but increased elastic modulus compared to non-aged PP. Graphene retarded the ageing of PP matrix, according to Fourier Transform Infrared spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) results. In the aged GNP/PP nanocomposite, the morphology did not present any changes and the examined properties were maintained to similar values with that of non-aged GNP/PP nanocomposite.
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Affiliation(s)
- Marianna Triantou
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos, Ag. Paraskevi 15310, Attiki, Greece
| | - Nadia Todorova
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos, Ag. Paraskevi 15310, Attiki, Greece
| | - Tatiana Giannakopoulou
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos, Ag. Paraskevi 15310, Attiki, Greece
| | - Tiverios Vaimakis
- Department of Chemistry, University of Ioannina, Ioannina, 45110, Greece
| | - Christos Trapalis
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos, Ag. Paraskevi 15310, Attiki, Greece
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12
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Triantou M, Todorova N, Giannakopoulou T, Vaimakis T, Trapalis C. Cover Image, Volume 66, Issue 12. POLYM INT 2017. [DOI: 10.1002/pi.5501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Marianna Triantou
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | - Nadia Todorova
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | - Tatiana Giannakopoulou
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | | | - Christos Trapalis
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
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Karapati S, Giannakopoulou T, Todorova N, Boukos N, Papailias I, Dimotikali D, Trapalis C. Novel ‘Pickering’ modified TiO 2 photocatalysts with high De-NOx efficiency. Catal Today 2017. [DOI: 10.1016/j.cattod.2017.01.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Triantou M, Todorova N, Giannakopoulou T, Vaimakis T, Trapalis C. Mechanical performance of re-extruded and aged graphene/polypropylene nanocomposites. POLYM INT 2017. [DOI: 10.1002/pi.5353] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Marianna Triantou
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | - Nadia Todorova
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | - Tatiana Giannakopoulou
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
| | | | - Christos Trapalis
- Institute of Nanoscience and Nanotechnology; National Center for Scientific Research ‘Demokritos’; Attikis Greece
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15
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Papadakis I, Krokos FD, Trapalis C. Interaction of analytical chemistry with accreditation/certification. Environ Sci Pollut Res Int 2017; 24:7872-7879. [PMID: 27146540 DOI: 10.1007/s11356-016-6638-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Affiliation(s)
- Ioannis Papadakis
- School of Science and Technology, Hellenic Open University, Patras, GR 263 35, Greece.
| | - Fragoulis D Krokos
- School of Science and Technology, Hellenic Open University, Patras, GR 263 35, Greece
- Hellenic Organization for Standardization, National Quality Infrastructure System, Peristeri, GR 121 33, Greece
| | - Christos Trapalis
- Hellenic Accreditation System, National Quality Infrastructure System, Kallithea, GR 176 76, Greece
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Papailias I, Todorova N, Giannakopoulou T, Yu J, Dimotikali D, Trapalis C. Photocatalytic activity of modified g-C 3 N 4 /TiO 2 nanocomposites for NOx removal. Catal Today 2017. [DOI: 10.1016/j.cattod.2016.06.032] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
A simple, facile and low-cost method for recycling of supercapacitor materials is proposed. This process aims to recover some fundamental components of a used supercapacitor, namely the electrolyte salt tetraethyl ammonium tetrafluoroborate (TEABF4) dissolved in an aprotic organic solvent such as acetonitrile (ACN), the carbonaceous material (activated charcoal, carbon nanotubes) purified, the current collector (aluminium foil) and the separator (paper) for further utilization. The method includes mechanical shredding of the supercapacitor in order to reduce its size, and separation of aluminium foil and paper from the carbonaceous resources containing TEABF4 by sieving. The extraction of TEABF4 from the carbonaceous material was based on its solubility in water and subsequent separation through filtering and distillation. A cyclic voltammetry curve of the recycled carbonaceous material revealed supercapacitor behaviour allowing a potential reutilization. Furthermore, as BF4(-) stemming from TEABF4 can be slowly hydrolysed in an aqueous environment, thus releasing F(-) anions, which are hazardous, we went on to their gradual trapping with calcium acetate and conversion to non-hazardous CaF2.
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Affiliation(s)
- Eleni C Vermisoglou
- Institute of Nanoscience & Nanotechnology, 'Demokritos', Ag. Paraskevi, Attikis, Greece
| | - Maria Giannouri
- Institute of Nanoscience & Nanotechnology, 'Demokritos', Ag. Paraskevi, Attikis, Greece
| | - Nadia Todorova
- Institute of Nanoscience & Nanotechnology, 'Demokritos', Ag. Paraskevi, Attikis, Greece
| | | | - Constantina Lekakou
- Division of Mechanical, Medical and Aerospace Engineering, University of Surrey, Guildford, UK
| | - Christos Trapalis
- Institute of Nanoscience & Nanotechnology, 'Demokritos', Ag. Paraskevi, Attikis, Greece
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Georgakilas V, Kouloumpis A, Gournis D, Bourlinos A, Trapalis C, Zboril R. Tuning the Dispersibility of Carbon Nanostructures from Organophilic to Hydrophilic: Towards the Preparation of New Multipurpose Carbon-Based Hybrids. Chemistry 2013; 19:12884-91. [DOI: 10.1002/chem.201301200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Indexed: 11/10/2022]
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21
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Todorova N, Vaimakis T, Petrakis D, Hishita S, Boukos N, Giannakopoulou T, Giannouri M, Antiohos S, Papageorgiou D, Chaniotakis E, Trapalis C. N and N,S-doped TiO2 photocatalysts and their activity in NOx oxidation. Catal Today 2013. [DOI: 10.1016/j.cattod.2012.11.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Sofianou MV, Trapalis C, Psycharis V, Boukos N, Vaimakis T, Yu J, Wang W. Study of TiO2 anatase nano and microstructures with dominant {001} facets for NO oxidation. Environ Sci Pollut Res Int 2012; 19:3719-3726. [PMID: 23054733 DOI: 10.1007/s11356-012-0747-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Accepted: 01/06/2012] [Indexed: 06/01/2023]
Abstract
INTRODUCTION TiO(2) anatase nanoplates and hollow microspheres were fabricated by a solvothermal-hydrothermal method using titanium isopropoxide as a titanium precursor and hydrofluoric acid as a capping agent in order to enhance the formation of the {001} crystal facets of the anatase nanocrystals. METHODS These different morphological structures of TiO(2) anatase can be achieved by only changing the solvent, keeping the amount of the precursor and of the capping agent identical during the solvothermal-hydrothermal process. RESULTS AND DISCUSSION After calcination of the samples, the adsorbed fluoride atoms on the {001} crystal facets of the TiO(2) anatase nanocrystals were completely removed from their surface according to XPS analysis. The calcined TiO(2) anatase structures were higher crystallized and the specific surface area of the catalysts increased, enhancing their photocatalytic activity in comparison to the non-calcined TiO(2) anatase structures. All TiO(2) anatase samples with adsorbed as well as non-adsorbed fluoride atoms on their {001} crystal facets, exhibited a higher photonic efficiency than Degussa P25, which was used as a reference. CONCLUSION The fluoride free TiO(2) anatase nanoplates exhibited the best photocatalytic activity in oxidizing the NO gas to NO(2) and NO(3) (-).
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Affiliation(s)
- Maria-Veronica Sofianou
- Institute of Materials Science, NCSR Demokritos, 153 10, Ag. Paraskevi, Athens, Attikis, Greece
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23
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Zbořil R, Karlický F, Bourlinos AB, Steriotis TA, Stubos AK, Georgakilas V, Šafářová K, Jančík D, Trapalis C, Otyepka M. Graphene fluoride: a stable stoichiometric graphene derivative and its chemical conversion to graphene. Small 2010; 6:2885-91. [PMID: 21104801 PMCID: PMC3020323 DOI: 10.1002/smll.201001401] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/04/2010] [Indexed: 05/18/2023]
Abstract
Stoichoimetric graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that graphene fluoride is the most thermodynamically stable of five studied hypothetical graphene derivatives; graphane, graphene fluoride, bromide, chloride, and iodide. The graphene fluoride is transformed into graphene via graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of graphene halides vary from zero for graphene bromide to 3.1 eV for graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.
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Affiliation(s)
- Radek Zbořil
- Regional Center of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, tr. 17. listopadu 12, Olomouc 77146Czech Republic E-mail:
| | - František Karlický
- Regional Center of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, tr. 17. listopadu 12, Olomouc 77146Czech Republic E-mail:
| | - Athanasios B Bourlinos
- Institute of Materials Science, NCSR “Demokritos”, Ag. Paraskevi AttikisAthens 15310, Greece E-mail:
| | - Theodore A Steriotis
- Institute of Physical Chemistry, NCSR “Demokritos”, Ag. Paraskevi AttikisAthens 15310, Greece
| | - Athanasios K Stubos
- Institute of Nuclear Technology and Radiation Protection, Environmental Research Laboratory, NCSR “Demokritos” Ag. Paraskevi AttikisAthens 15310, Greece
| | - Vasilios Georgakilas
- Institute of Materials Science, NCSR “Demokritos”, Ag. Paraskevi AttikisAthens 15310, Greece E-mail:
| | - Klára Šafářová
- Regional Center of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, tr. 17. listopadu 12, Olomouc 77146Czech Republic E-mail:
| | - Dalibor Jančík
- Institute of Materials Science, NCSR “Demokritos”, Ag. Paraskevi AttikisAthens 15310, Greece E-mail:
| | - Christos Trapalis
- Institute of Materials Science, NCSR “Demokritos”, Ag. Paraskevi AttikisAthens 15310, Greece E-mail:
| | - Michal Otyepka
- Regional Center of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, tr. 17. listopadu 12, Olomouc 77146Czech Republic E-mail:
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Šojić D, Despotović V, Abramović B, Todorova N, Giannakopoulou T, Trapalis C. Photocatalytic degradation of mecoprop and clopyralid in aqueous suspensions of nanostructured N-doped TiO2. Molecules 2010; 15:2994-3009. [PMID: 20657461 PMCID: PMC6263289 DOI: 10.3390/molecules15052994] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 03/18/2010] [Accepted: 04/20/2010] [Indexed: 11/28/2022] Open
Abstract
The work describes a study of the oxidation power of N-doped and undoped anatase TiO2, as well as TiO2 Degussa P25 suspensions for photocatalytic degradation of the herbicides RS-2-(4-chloro-o-tolyloxy)propionic acid (mecoprop) and 3,6-dichloro-pyridine-2-carboxylic acid (clopyralid) using visible and UV light. Undoped nanostructured TiO2 powder in the form of anatase was prepared by a sol-gel route. The synthesized TiO2, as well as TiO2 Degussa P25 powder, were modified with urea to introduce nitrogen into the structure. N-doped TiO2 appeared to be somewhat more efficient than the starting TiO2 (anatase) powder when visible light was used for mecoprop degradation. N-doped TiO2 Degussa P25 was also slightly more efficient than TiO2 Degussa P25. However, under the same experimental conditions, no degradation of clopyralid was observed in the presence of any of the mentioned catalysts. When the kinetics of mecoprop degradation was studied using UV light, more efficient were the undoped powders, while in the case of clopyralid, N-doped TiO2 Degussa P25 powder was most efficient, which is probably a consequence of the difference in the molecular structure of the two herbicides.
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Affiliation(s)
- Daniela Šojić
- Department of Chemistry, Faculty of Science, University of Novi Sad, Trg D. Obradovića 3, 21000 Novi Sad, Serbia; E-Mails: (D.Š.); (V.D.)
| | - Vesna Despotović
- Department of Chemistry, Faculty of Science, University of Novi Sad, Trg D. Obradovića 3, 21000 Novi Sad, Serbia; E-Mails: (D.Š.); (V.D.)
| | - Biljana Abramović
- Department of Chemistry, Faculty of Science, University of Novi Sad, Trg D. Obradovića 3, 21000 Novi Sad, Serbia; E-Mails: (D.Š.); (V.D.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +381-21-485-2753; Fax: +381-21-454-065
| | - Nadia Todorova
- Laboratory of Nanocomposite and Nanofunctional Materials, IMS, NCSR Demokritos, Athens 153 10, Greece; E-Mails: (N.T.); (T.G.); (C.T.)
| | - Tatiana Giannakopoulou
- Laboratory of Nanocomposite and Nanofunctional Materials, IMS, NCSR Demokritos, Athens 153 10, Greece; E-Mails: (N.T.); (T.G.); (C.T.)
| | - Christos Trapalis
- Laboratory of Nanocomposite and Nanofunctional Materials, IMS, NCSR Demokritos, Athens 153 10, Greece; E-Mails: (N.T.); (T.G.); (C.T.)
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Abstract
Graphene sheets derived from dispersion of graphite in pyridine were functionalised by the 1,3 dipolar cycloaddition of azomethine ylide. The organically modified graphene sheets are easily dispersible in polar organic solvents and water, and they are extensively characterised using several spectroscopic and microscopy techniques.
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Affiliation(s)
- Vasilios Georgakilas
- Institute of Material Science, N.C.S.R Demokritos, 15310 Ag. Paraskevi, Attikis, Greece.
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Belessi V, Romanos G, Boukos N, Lambropoulou D, Trapalis C. Removal of Reactive Red 195 from aqueous solutions by adsorption on the surface of TiO2 nanoparticles. J Hazard Mater 2009; 170:836-844. [PMID: 19540670 DOI: 10.1016/j.jhazmat.2009.05.045] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 05/07/2009] [Accepted: 05/12/2009] [Indexed: 05/27/2023]
Abstract
Nanoparticles of TiO2 were synthesized and characterized by XRD, BET, TG/DTA and TEM measurements. The commercial azo dye Reactive Red 195 (RR195) was selected as a model dye in order to examine the adsorption capacity of TiO2 at room temperature, under dark conditions. It was demonstrated that RR195 could be efficiently adsorbed in aqueous suspension of TiO2. A study on the effects of various parameters like initial pH, concentration of dye and concentration of adsorbent has been carried out in order to find optimum adsorption conditions. The optimum pH of sorption was 3. Substantial reduction of COD, besides removal of colour, was also achieved. The experimental data were analyzed by the Langmuir and Freundlich adsorption models. Equilibrium data fitted very well with the Langmuir model signifying the energetic homogeneity of TiO2 surface adsorption sites. At the temperature of 30 degrees C, the maximum monolayer adsorption capacity obtained from the Langmuir model is approximately 87 mg/g (pH 3.0). Kinetic studies were carried out and showed a rapid sorption of dye in the first 30 min while equilibrium was reached at 1h. Three kinetic adsorption models were used to describe the kinetics data, the pseudo-first-order model, the pseudo-second-order model and the intraparticle diffusion model. The sorption kinetics of dye was best described by the pseudo-second-order kinetic model.
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Affiliation(s)
- V Belessi
- Institute of Materials Science, NCSR "Demokritos", 15310 Aghia Paraskevi Attikis, Athens, Greece.
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Georgakilas V, Bourlinos A, Gournis D, Tsoufis T, Trapalis C, Mateo-Alonso A, Prato M. Multipurpose organically modified carbon nanotubes: from functionalization to nanotube composites. J Am Chem Soc 2008; 130:8733-40. [PMID: 18597430 DOI: 10.1021/ja8002952] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We show that covalent functionalization of carbon nanotubes (CNTs) via 1,3-dipolar cycloaddition is a powerful method for enhancing the ability to process CNTs and facilitating the preparation of hybrid composites, which is achieved solely by mixing. CNTs were functionalized with phenol groups, providing stable dispersions in a range of polar solvents, including water. Additionally, the functionalized CNTs could easily be combined with polymers and layered aluminosilicate clay minerals to give homogeneous, coherent, transparent CNT thin films and gels.
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Affiliation(s)
- Vasilios Georgakilas
- Institute of Materials Science, N.C.S.R. Demokritos, GR-15310 Agia Paraskevi Athens, Greece
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Bourlinos AB, Dallas P, Sanakis Y, Stamopoulos D, Trapalis C, Niarchos D. Synthesis and characterization of a π-conjugate, covalent layered network derived from condensation polymerization of the 4,4′-bipyridine-cyanuric chloride couple. Eur Polym J 2006. [DOI: 10.1016/j.eurpolymj.2006.07.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
The purpose of this study was to qualitatively and quantitatively assess the nickel, chromium, and ferrous levels in a population of 17 orthodontic patients undergoing treatment, compared with seven untreated individuals, employing a novel methodological approach and a new analytical technique. Salivary samples obtained from patients before and after rinsing with double distilled water were processed for Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) for simultaneous estimation of the concentration of the metallic elements. No statistically significant difference was detected between control and patient groups with respect to salivary metal content, regardless of element. The range of salivary metal levels found did not exceed those of daily intake through food and air. The lack of a continuous monitoring scheme for salivary metal concentrations in real time may impose substantial obstacles to defining the release rate of metals in vivo. The results of this study emphasize the necessity of incorporating the dimension of time in assessing the release potential of orthodontic alloys.
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Affiliation(s)
- Theodore Eliades
- Biomaterials Science Unit, University of Manchester, Dental School, UK
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Chryssikos GD, Patsis AP, Kamitsos EI, Kapoutsis JA, Karakassides MA, Trapalis C, Mylonas E, Kordas G. A structural assessment of glass formation in alkali borates: Melt quenching versus gel drying. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/bf00275619] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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