2023
4.
Koutsioukis, Apostolos; Vrettos, Katerina; Belessi, Vassiliki; Georgakilas, Vasilios
Conductivity Enhancement of Graphene and Graphene Derivatives by Silver Nanoparticles Journal Article
In: Applied Sciences, vol. 13, no. 13, 2023, ISSN: 2076-3417.
Abstract | Links | BibTeX | Tags: Conductive inks, graphene hybrid, gravure printing, silver nanoparticles
@article{app13137600,
title = {Conductivity Enhancement of Graphene and Graphene Derivatives by Silver Nanoparticles},
author = {Apostolos Koutsioukis and Katerina Vrettos and Vassiliki Belessi and Vasilios Georgakilas},
url = {https://www.mdpi.com/2076-3417/13/13/7600},
doi = {10.3390/app13137600},
issn = {2076-3417},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
journal = {Applied Sciences},
volume = {13},
number = {13},
abstract = {In this article, a facile way for the doping of graphene and graphene derivatives with silver nanoparticles at different Ag ratios is described. Ag nanoparticles were formed directly on the surface of two different graphene substrates dispersed in dimethylformamide by the reduction of Ag cations with NaBH4. A few layered graphene nanosheets (FLG) produced from graphite and reduced graphene oxide functionalized with amino arylsulfonates (f-rGO) were used as substrates. The final graphene/Ag nanoparticle hybrid in the form of solid, dense spots showed enhanced electrical conductivity, which can be attributed to the formation of conductive interconnections between the 2D nanosheets. Importantly, electrical conductivities of 20 and 167 103 S m−1 were measured for the hybrids of f-rGO and FLG, respectively, with the higher Ag percentage without an annealing process. A representative hybrid f-rGO with Ag nanoparticles was used for the development of a highly conductive water-based gravure ink with excellent printing properties.},
keywords = {Conductive inks, graphene hybrid, gravure printing, silver nanoparticles},
pubstate = {published},
tppubtype = {article}
}
In this article, a facile way for the doping of graphene and graphene derivatives with silver nanoparticles at different Ag ratios is described. Ag nanoparticles were formed directly on the surface of two different graphene substrates dispersed in dimethylformamide by the reduction of Ag cations with NaBH4. A few layered graphene nanosheets (FLG) produced from graphite and reduced graphene oxide functionalized with amino arylsulfonates (f-rGO) were used as substrates. The final graphene/Ag nanoparticle hybrid in the form of solid, dense spots showed enhanced electrical conductivity, which can be attributed to the formation of conductive interconnections between the 2D nanosheets. Importantly, electrical conductivities of 20 and 167 103 S m−1 were measured for the hybrids of f-rGO and FLG, respectively, with the higher Ag percentage without an annealing process. A representative hybrid f-rGO with Ag nanoparticles was used for the development of a highly conductive water-based gravure ink with excellent printing properties.
2022
3.
Giasafaki, D.; Mitzithra, C.; Belessi, V.; Filippakopoulou, T.; Koutsioukis, A.; Georgakilas, V.; Charalambopoulou, G.; Steriotis, T.
Graphene-Based Composites with Silver Nanowires for Electronic Applications Journal Article
In: Nanomaterials, vol. 12, iss. 19, no. 3443, 2022.
Abstract | Links | BibTeX | Tags: Conductive inks, few-layered graphene, functionalized multiwalled carbon nanotubes, functionalized reduced graphene oxide, Gravure, Printed electronics, silver nanowires
@article{Giasafaki2022,
title = {Graphene-Based Composites with Silver Nanowires for Electronic Applications},
author = {D. Giasafaki and C. Mitzithra and V. Belessi and T. Filippakopoulou and A. Koutsioukis and V. Georgakilas and G. Charalambopoulou and T. Steriotis },
doi = {https://doi.org/10.3390/nano12193443 },
year = {2022},
date = {2022-10-01},
urldate = {2022-10-01},
journal = {Nanomaterials},
volume = {12},
number = {3443},
issue = {19},
abstract = {Graphene/metal nanocomposites have shown a strong potential for use in electronic applications. In particular, the combination of silver nanowires (AgNWs) with graphene derivatives leads to the formation of an efficient conductive network, thus improving the electrical properties of a composite. This work focused on developing highly conductive hydrophilic hybrids of simultaneously functionalized and reduced graphene oxide (f-rGO) and AgNWs in different weight ratios by following two different synthetic routes: (a) the physical mixture of f-rGO and AgNWs, and (b) the in situ reduction of GO in the presence of AgNWs. In addition, the role of AgNWs in improving the electrical properties of graphene derivatives was further examined by mixing AgNWs with a hybrid of few-layered graphene with functionalized multiwalled carbon nanotubes (FLG/MWNT-f-OH). The studied materials showed a remarkable improvement in the overall electrical conductivity due to the synergistic effect of their components, which was proportional to the percentage of Ag and dependent on the procedure of the hybrid formation. One of the f-rGO/AgNWs composites was also selected for the preparation of gravure printing inks that were tested to determine their rheological and printing properties. All of the f-rGO/AgNWs composites were shown to be very promising materials for use as conductive inks for flexible electronics.},
keywords = {Conductive inks, few-layered graphene, functionalized multiwalled carbon nanotubes, functionalized reduced graphene oxide, Gravure, Printed electronics, silver nanowires},
pubstate = {published},
tppubtype = {article}
}
Graphene/metal nanocomposites have shown a strong potential for use in electronic applications. In particular, the combination of silver nanowires (AgNWs) with graphene derivatives leads to the formation of an efficient conductive network, thus improving the electrical properties of a composite. This work focused on developing highly conductive hydrophilic hybrids of simultaneously functionalized and reduced graphene oxide (f-rGO) and AgNWs in different weight ratios by following two different synthetic routes: (a) the physical mixture of f-rGO and AgNWs, and (b) the in situ reduction of GO in the presence of AgNWs. In addition, the role of AgNWs in improving the electrical properties of graphene derivatives was further examined by mixing AgNWs with a hybrid of few-layered graphene with functionalized multiwalled carbon nanotubes (FLG/MWNT-f-OH). The studied materials showed a remarkable improvement in the overall electrical conductivity due to the synergistic effect of their components, which was proportional to the percentage of Ag and dependent on the procedure of the hybrid formation. One of the f-rGO/AgNWs composites was also selected for the preparation of gravure printing inks that were tested to determine their rheological and printing properties. All of the f-rGO/AgNWs composites were shown to be very promising materials for use as conductive inks for flexible electronics.
2019
2.
Georgitsopoulou, S.; Petrai, O.; Georgakilas, V.
Highly conductive functionalized reduced graphene oxide Journal Article
In: Surfaces and Interfaces, vol. 16, pp. 152-156, 2019, ISSN: 2468-0230.
Abstract | Links | BibTeX | Tags: 1, 3 dipolar cycloaddition, Carbon nanostructures, Conductive inks, Graphene oxide, Reduced graphene oxide
@article{Georgitsopoulou2019,
title = {Highly conductive functionalized reduced graphene oxide},
author = {S. Georgitsopoulou and O. Petrai and V. Georgakilas },
doi = {https://doi.org/10.1016/j.surfin.2019.05.010},
issn = {2468-0230},
year = {2019},
date = {2019-09-01},
urldate = {2019-09-01},
journal = {Surfaces and Interfaces},
volume = {16},
pages = {152-156},
abstract = {Graphene oxide (GO) is a derivative of graphene that is formed by the exfoliation of graphite oxide; product of graphite treatment with strong oxidants [1], [2], [3], [4]. GO nanosheets are decorated by epoxy and hydroxyl groups at the bulk and carboxylates mainly at the edges, while small isolated aromatic areas complete the surface [4], [5], [6]. The hydrophilic character of GO, due to the oxygen groups, induces high dispersibility in water or other polar solvents such as ethanol or dimethylformamide (DMF) [6], [7]. On the other hand, due to the very low aromatic character, GO is practically non conductive. 1,3 dipolar cycloaddition of azomethine ylide on GO in DMF was followed by a simultaneous reduction of GO. The as prepared functionalized reduced graphene oxide showed excellent stability in water and high electrical conductivity.},
keywords = {1, 3 dipolar cycloaddition, Carbon nanostructures, Conductive inks, Graphene oxide, Reduced graphene oxide},
pubstate = {published},
tppubtype = {article}
}
Graphene oxide (GO) is a derivative of graphene that is formed by the exfoliation of graphite oxide; product of graphite treatment with strong oxidants [1], [2], [3], [4]. GO nanosheets are decorated by epoxy and hydroxyl groups at the bulk and carboxylates mainly at the edges, while small isolated aromatic areas complete the surface [4], [5], [6]. The hydrophilic character of GO, due to the oxygen groups, induces high dispersibility in water or other polar solvents such as ethanol or dimethylformamide (DMF) [6], [7]. On the other hand, due to the very low aromatic character, GO is practically non conductive. 1,3 dipolar cycloaddition of azomethine ylide on GO in DMF was followed by a simultaneous reduction of GO. The as prepared functionalized reduced graphene oxide showed excellent stability in water and high electrical conductivity.
2018
1.
Belessi, V.; Petridis, D.; Steriotis, T.; Spyrou, K.; Manolis, G. K.; Psycharis, V.; Georgakilas, V.
Simultaneous reduction and surface functionalization of graphene oxide for highly conductive and water dispersible graphene derivatives Journal Article
In: SN Applied Sciences, vol. 1, iss. 77, 2018.
Abstract | Links | BibTeX | Tags: Conductive inks, Gravure, Printed electronics, Reduced graphene oxide, Surface functionalization
@article{Belessi2018,
title = {Simultaneous reduction and surface functionalization of graphene oxide for highly conductive and water dispersible graphene derivatives},
author = {V. Belessi and D. Petridis and T. Steriotis and K. Spyrou and G. K. Manolis and V. Psycharis and V. Georgakilas },
doi = {https://doi.org/10.1007/s42452-018-0077-9},
year = {2018},
date = {2018-12-03},
urldate = {2018-12-03},
journal = {SN Applied Sciences},
volume = {1},
issue = {77},
abstract = {A simple and effective preparation method for the simultaneous reduction and functionalization of graphene oxide (rGO) by 2,4-diamino benzene sulfonic acid has been developed. The derivatives exhibit excellent conductivity and high dispersibility in various solvents. The successful preparation of rGO and the presence of the sulfonated aromatic diamine on rGO surface has been confirmed by infrared and X-ray photoelectron spectroscopy, while, the analysis by micro-Raman spectroscopy indicated that the reduction/functionalization alters the lattice structure of GO by the increment the defect density when the 2,4-diamino benzene sulfonic acid is used. Moreover, the study of the dried products by X-ray diffraction spectroscopy suggested the turbostratic restacking of the exfoliated rGO into graphite-like nanostructures. The obtained derivative of simultaneous reduction and functionalization of GO was used for the preparation of highly conductive water-based gravure ink, which in turn, was successfully applied in printing on various flexible substrates, demonstrating its great potentiality in graphene-based flexible and printed electronics applications.},
keywords = {Conductive inks, Gravure, Printed electronics, Reduced graphene oxide, Surface functionalization},
pubstate = {published},
tppubtype = {article}
}
A simple and effective preparation method for the simultaneous reduction and functionalization of graphene oxide (rGO) by 2,4-diamino benzene sulfonic acid has been developed. The derivatives exhibit excellent conductivity and high dispersibility in various solvents. The successful preparation of rGO and the presence of the sulfonated aromatic diamine on rGO surface has been confirmed by infrared and X-ray photoelectron spectroscopy, while, the analysis by micro-Raman spectroscopy indicated that the reduction/functionalization alters the lattice structure of GO by the increment the defect density when the 2,4-diamino benzene sulfonic acid is used. Moreover, the study of the dried products by X-ray diffraction spectroscopy suggested the turbostratic restacking of the exfoliated rGO into graphite-like nanostructures. The obtained derivative of simultaneous reduction and functionalization of GO was used for the preparation of highly conductive water-based gravure ink, which in turn, was successfully applied in printing on various flexible substrates, demonstrating its great potentiality in graphene-based flexible and printed electronics applications.