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3. Non-conductive ferromagnetic carbon-coated (Co, Ni) metal/polystyrene nanocomposites films.

Author

Takacs, H., Viala, B., Tortai, J.-H., Hermán, V., and Duclairoir, F.

Subjects
FERROMAGNETIC materials, POLYSTYRENE, NANOCOMPOSITE materials, ELECTRIC insulators & insulation, MAGNETIZATION transfer
Abstract

This article reports non-conductive ferromagnetic properties of metal/polymer nanocomposite films intended to be used for RF applications. The nanocomposite arrangement is unique showing a core double-shell structure of metal-carbon-polystyrene: M/C//P1/P2, where M=Co, Ni is the core material, C=graphene or carbon is the first shell acting as a protective layer against oxidation, P1=pyrene-terminated polystyrene is the second shell for electrical insulation, and P2=polystyrene is a supporting matrix (// indicates actual grafting). The nanocomposite formulation is briefly described, and the film deposition by spin-coating is detailed. Original spin-curves are reported and analyzed. One key outcome is the achievement of uniform and cohesive films at the wafer scale. Structural properties of films are thoroughly detailed, and weight and volume fractions of M/C are considered. Then, a comprehensive overview of DC magnetic and electrical properties is reported. A discussion follows on the magnetic softness of the nanocomposites vs. that of a single particle (theoretical) and the raw powder (experimental). Finally, unprecedented achievement of high magnetization (~0.6 T) and ultra-high resistivity (~1010µΩ cm) is shown. High magnetization comes from the preservation of the existing protective shell C, with no significant degradation on the particle net-moment, and high electrical insulation is ensured by adequate grafting of the secondary shell P1. To conclude, the metal/polymer nanocomposites are situated in the landscape of soft ferromagnetic materials for RF applications (i.e., inductors and antennas), by means of two phase-diagrams, where they play a crucial role. [ABSTRACT FROM AUTHOR]

Published
2016
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4. PEDOT:PSS Electroactive Binder for Silicon Nanoparticles in Li-Ion Battery Applications

Author

Mery, Adrien, Pierre, Bernard, Chandesris, Marion, Haon, Cédric, Alper, John P., Herlin, Nathalie, Duclairoir, F., Sadki, Saïd, SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Vaughey, J. T., Meng, Y. S., Yang, J., Kulesza, P. J., Di Noto, V., Palacin, Serge, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

Silicon is for many years a coveted Li-ion battery material by the scientific community. This material exhibits a high theoretical specific capacity of 3579 mAh/g (10 times higher than graphite material) making it very promising for Li-ion negative electrodes. However, two main problems appear with silicon electrode during cycling, its structural degradation (leading to a loss of contact between silicon particles) and the instability of the Solid Electrolyte Interphase (SEI), mainly due to the huge volume expansion of Silicon particles during cycling (around 300 %). Different ways have been studied to tackle these problems, including the nanostructuration of Si particles to reduce the stress undergone during charge/discharge cycles. More recently, the use of conducting polymers as binders inside the electrode formulation was studied in place of classical binders like PVDF or CMC. The use of a conducting polymer as an alternative to traditional insulating binder in combination with conductive additive (carbon black, graphene…) allows to play the role of both binder and electronical conductor. Consequently, it leads to reduce space and interfacial parameters by the elimination of these inorganic (and non-active) conductive materials in the electrode formulation. The conducting polymer used in this work is the PEDOT:PSS. This polymer is well known for its good chemical and mechanical stability and its potential high electrical conductivity (10-2 to 103 S/cm). It is mainly studied in the domain of photovoltaic and its use in the battery domain for electrode formulations begins to appear. The results of this study will be devoted to the evaluation of Li-ion negative electrode containing Silicon (or Silicon@carbon composite) nanoparticles with PEDOT:PSS binder. Si and Si@C nanoparticles are synthesized by laser pyrolysis. This process offers the possibility to decrease the size of the particles and to coat the silicon by a carbon shell, all in one step of synthesis. Electrode formulations containing the active material (Si or Si@C) and the PEDOT: PSS binder (without other additives) are coated on a Cu current collector to perform electrochemical tests. Cyclic voltammetry, Electrochemical Impedance Spectroscopy (EIS) and galvanostatic cycling were performed in half-cells containing the Si (or Si@C)/PEDOT:PSS electrode versus a lithium foil. Specific capacities up to 1000-1500 mAh/g and stable over more than a hundred cycles of charge/discharge were achieved. These very encouraging results highlight the potential of PEDOT:PSS as electroactive binder for silicon electrodes in Li-ion batteries. Figure 1

Published
2018
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5. Thin film of magnetic nanocomposites with zero effective conductivity for RF applications

Author

Takacs, H., Viala, B., Gourgon, C., Duclairoir, F., jean-herve tortai, Laboratoire des technologies de la microélectronique (LTM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Clot, Marielle, and Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2013

6. Interest of Surface Molecular Grafting for Electrochemical Storage Applications

Author

Gaubicher, Joël, Madec, L., Blanchard, Philippe, Kumar, A., Duclairoir, F., Bidan, G., Lestriez, Bernard, Guyomard, Dominique, Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN), MOLTECH-Anjou, and Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM]Chemical Sciences
Published
2013

7. Magnetic films of metal-graphene-polymer nanocomposites

Author

Takacs, H., Viala, B., Gourgon, C., Duclairoir, F., jean-herve tortai, Clot, Marielle, Laboratoire des technologies de la microélectronique (LTM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), and Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2013

8. Electronic properties of gold catalyst silicon nanowires by photoluminescence: the role of the surface

Author

Demichel, O., Calvo, V., Noe, P., Benoit À La Guillaume, Q., Pauc, N., Salem, B., Coustel, R., Duclairoir, F., Oehler, F., Gentile, P., Silicon Nanoelectronics Photonics and Structures (SiNaps), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire des technologies de la microélectronique (LTM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electronique Moléculaire Organique et Hybride (LEMOH), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011

9. From Atomistic to Device Level Investigation of Hybrid Redox Molecular/Silicon Field-Effect Memory Devices

Author

Pro T, Buckley J, Barattin R, Calborean A, Aiello V, Nicotra G, Huang K, Gely M, Delapierre G, Jalaguier E, Duclairoir F, Chevalier N, Lombardo S, Maldivi P, Ghibaudo G, De Salvo B, and Deleonibus S

Abstract

In this paper, an extensive investigation of hybrid molecular/Si field-effect memories is presented, where redox ferrocene (Fc) molecules play the role of the memory charge storage nodes. Engineering of the organic linkers between Fc and Si is achieved by grafting Fc with different linker lengths. The study shows a clear correlation between results from atomistic computational density functional theory, electrochemical measurements (cyclic voltammetry) and electrical data obtained by a detailed study on capacitors and pseudo-MOS devices. Physical-chemical analyses (atomic force microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy), corroborate the quality of molecular layers on devices.

Published
2011

12. From Atomistic to Device Level Investigation of Hybrid Redox Molecular/Silicon Field-Effect Memory Devices IMW

Author

Buckley, J., Pro, T., Barattin, R., Calborean, A., Huang, K., Aiello, V., Nicotra, G., Gely, M., Delapierre, G., Jalaguier, E., Duclairoir, F., Chevalier, N., Mariolle, D., Spinella, C., Lombardo, S., Blaise, P., Maldivi, P., gerard ghibaudo, Baptist, R., Salvo, B., Domenget, Chahla, Institut de biologie et chimie des protéines [Lyon] (IBCP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Techniques de l'Informatique et de la Microélectronique pour l'Architecture des systèmes intégrés (TIMA), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institute of VLSI Design, Zhejiang University, Laboratoire de psychologie cognitive (LPC), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Techniques of Informatics and Microelectronics for integrated systems Architecture (TIMA), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire d'Electronique et des Technologies de l'Information (CEA-LETI), Université Grenoble Alpes (UGA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), and Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National Polytechnique de Grenoble (INPG)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Grenoble Alpes (UGA)

Subjects
[SPI.NANO] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2009

13. From Atomistic to Device Level Investigation of Hybrid Redox Molecular/Silicon Field-Effect Memory Devices

Author

Buckley J, Pro T, Barattin R, Calborean A, Huang K, Aiello V, Nicotra G, Gely M, Delapierre G, Jalaguier E, Duclairoir F, Chevalier N, Mariolle D, Spinella C, Lombardo S, Blaise P, Maldivi P, Ghibaudo G, Baptist R, and De Salvo B

Subjects
Molecular electronics, Density functional theory, Memories, MOS devices, Atomic Force Microscopy
Abstract

In this paper an extensive investigation of hybrid molecular/silicon field-effect memories is presented, where Redox Ferrocene (Fc) molecules play the role of the memory charge storage nodes. Engineering of the organic linkers between Fc and Si is achieved by grafting Fc with different linker lengths. The study shows a clear correlation between results from atomistic computational Density Functional Theory (DFT), electrochemical measurements (Cyclic Voltammetry) and electrical data obtained by a detailed study on Pseudo-MOS devices. Physical-chemical analyses (Atomic Force Microscopy, high-resolution Transmission Electron Microscopy, X-Ray Photoclectron Spectroscopy), were used to monitor the molecular layers.

Published
2009

16. From Atomistic to Device Level Investigation of Hybrid Redox Molecular/Silicon Field-Effect Memory Devices

Author

Buckley, J., primary, Pro, T., additional, Barattin, R., additional, Calborean, A., additional, Huang, K., additional, Aiello, V., additional, Nicotra, G., additional, Gely, M., additional, Delapierre, G., additional, Jalaguier, E., additional, Duclairoir, F., additional, Chevalier, N., additional, Mariolle, D., additional, Spinella, C., additional, Lombardo, S., additional, Blaise, P., additional, Maldivi, P., additional, Ghibaudo, G., additional, Baptist, R., additional, and De Salvo, B., additional

Published
2009
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19. On the Influence of Molecular Linker on Charge Transfer Rate in Hybrid Molecular (Ferrocene)/Silicon Field Effect Memories

Author

Buckley, J., primary, Pro, T., additional, Barattin, R., additional, Calborean, A., additional, Gely, M., additional, Huang, K., additional, Delapierre, G., additional, Duclairoir, F., additional, Jalaguier, E., additional, Maldivi, P., additional, De Salvo, B., additional, Deleonibus, S., additional, and Ghibaudo, G., additional

Published
2008
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20. Toward the Improvement of Silicon-Based Composite Electrodes via an In-Situ Si@C-Graphene Composite Synthesis for Li-Ion Battery Applications.

Author

Mery A, Chenavier Y, Marcucci C, Benayad A, Alper JP, Dubois L, Haon C, Boime NH, Sadki S, and Duclairoir F

Abstract

Using Si as anode materials for Li-ion batteries remain challenging due to its morphological evolution and SEI modification upon cycling. The present work aims at developing a composite consisting of carbon-coated Si nanoparticles (Si@C NPs) intimately embedded in a three-dimensional (3D) graphene hydrogel (GHG) architecture to stabilize Si inside LiB electrodes. Instead of simply mixing both components, the novelty of the synthesis procedure lies in the in situ hydrothermal process, which was shown to successfully yield graphene oxide reduction, 3D graphene assembly production, and homogeneous distribution of Si@C NPs in the GHG matrix. Electrochemical characterizations in half-cells, on electrodes not containing additional conductive additive, revealed the importance of the protective C shell to achieve high specific capacity (up to 2200 mAh.g -1 ), along with good stability (200 cycles with an average Ceff > 99%). These performances are far superior to that of electrodes made with non-C-coated Si NPs or prepared by mixing both components. These observations highlight the synergetic effects of C shell on Si NPs, and of the single-step in situ preparation that enables the yield of a Si@C-GHG hybrid composite with physicochemical, structural, and morphological properties promoting sample conductivity and Li-ion diffusion pathways.

Published
2023
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21. Sparsely Pillared Graphene Materials for High-Performance Supercapacitors: Improving Ion Transport and Storage Capacity.

Author

Banda H, Périé S, Daffos B, Taberna PL, Dubois L, Crosnier O, Simon P, Lee D, De Paëpe G, and Duclairoir F

Abstract

Graphene-based materials are extensively studied as promising candidates for supercapacitors (SCs) owing to the high surface area, electrical conductivity, and mechanical flexibility of graphene. Reduced graphene oxide (RGO), a close graphene-like material studied for SCs, offers limited specific capacitances (100 F·g -1 ) as the reduced graphene sheets partially restack through π-π interactions. This paper presents pillared graphene materials designed to minimize such graphitic restacking by cross-linking the graphene sheets with a bifunctional pillar molecule. Solid-state NMR, X-ray diffraction, and electrochemical analyses reveal that the synthesized materials possess covalently cross-linked graphene galleries that offer additional sites for ion sorption in SCs. Indeed, high specific capacitances in SCs are observed for the graphene materials synthesized with an optimized number of pillars. Specifically, the straightforward synthesis of a graphene hydrogel containing pillared structures and an interconnected porous network delivered a material with gravimetric capacitances two times greater than that of RGO (200 F·g -1 vs 107 F·g -1 ) and volumetric capacitances that are nearly four times larger (210 F·cm -3 vs 54 F·cm -3 ). Additionally, despite the presence of pillars inside the graphene galleries, the optimized materials show efficient ion transport characteristics. This work therefore brings perspectives for the next generation of high-performance SCs.

Published
2019
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22. Evidence for Charge Transfer at the Interface between Hybrid Phosphomolybdate and Epitaxial Graphene.

Author

Huder L, Rinfray C, Rouchon D, Benayad A, Baraket M, Izzet G, Lipp-Bregolin F, Lapertot G, Dubois L, Proust A, Jansen L, and Duclairoir F

Abstract

The interfacing of polyoxometalates and graphene can be considered to be an innovative way to generate hybrid structures that take advantage of the properties of both components. Polyoxometalates are redox-sensitive and photosensitive compounds with high temperature stability (up to 400 °C for some), showing tunable properties depending on the metal incorporated inside the complex. Graphene has a unique electronic band structure combined with good material properties for electrical and optical applications. The spontaneous, rather than electrochemical, functionalization of epitaxial graphene on SiC with Keggin phosphomolybdate derivative TBA3[PMo11O39{Sn(C6H4)C≡C(C6H4)N2}] (named K(Mo)Sn[N2(+)]) bearing a phenyl diazonium unit is investigated. Graphene decoration is evidenced by means of AFM, Raman, XPS, and cyclic voltammetry, indicating a successful immobilization of the polyoxomolybdate. The covalent bonding of the polyoxometalate to the graphene substrate can be deduced from the appearance of a D band in the Raman spectra and from the loss of mobility in the electrical conduction. High-resolution XPS spectra reveal an electron transfer from the graphene to the Mo complex. The comparison of charge-carrier density measurements before and after grafting supports the p-type doping effect, which is further evidenced by work function UPS measurements.

Published
2016
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23. Non-conductive ferromagnets based on core double-shell nanoparticles for radio-electric applications.

Author

Takacs H, Viala B, Hermán V, Tortai JH, Duclairoir F, Alarcon Ramos J, Jouneau PH, Okuno H, and Tallec G

Abstract

Two fabrication schemes of magnetic metal-polymer nanocomposites films are described. The nanocomposites are made of graphene-coated cobalt nanoparticles embedded in a polystyrene matrix. Scheme 1 uses non-covalent chemistry while scheme 2 involves covalent bonding with radicals. Preservation of the net-moment of cobalt and electrical insulation are achieved by means of a core double-shell structure of cobalt-graphene-polystyrene. The graphene shell has two functions: it is a protective layer against metal core oxidation and it serves as the functionalization surface for polymer grafting as well. The polystyrene shell is used as an insulating layer between nanoparticles and improves nanoparticles dispersion inside the polystyrene matrix. The theoretical maximum volume filling ratio estimated at ~30 % is almost reached. The nanocomposites are shown to undergo percolation behavior but retain low conductivity (<1 S/m) at the highest filling ratio reached ~25 % leading to extremely low losses (10(-3)) at high frequency. Such low conductivity values are combined with large magnetization, as high as 0.9 T. Ability for radiofrequency applications is discussed in regards to the obtained magnetization.

Published
2016
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24. Solid-State NMR and DFT Combined for the Surface Study of Functionalized Silicon Nanoparticles.

Author

Lee D, Kaushik M, Coustel R, Chenavier Y, Chanal M, Bardet M, Dubois L, Okuno H, Rochat N, Duclairoir F, Mouesca JM, and De Paëpe G

Abstract

Silicon nanoparticles (NPs) serve a wide range of optical, electronic, and biological applications. Chemical grafting of various molecules to Si NPs can help to passivate their reactive surfaces, "fine-tune" their properties, or even give them further interesting features. In this work, (1) H, (13) C, and (29) Si solid-state NMR spectroscopy has been combined with density functional theory calculations to study the surface chemistry of hydride-terminated and alkyl-functionalized Si NPs. This combination of techniques yields assignments for the observed chemical shifts, including the contributions resulting from different surface planes, and highlights the presence of physisorbed water. Resonances from near-surface (13) C nuclei were shown to be substantially broadened due to surface disorder and it is demonstrated that in an ambient environment hydride-terminated Si NPs undergo fast back-bond oxidation, whereas long-chain alkyl-functionalized Si NPs undergo slow oxidation. Furthermore, the combination of NMR spectroscopy and DFT calculations showed that the employed hydrosilylation reaction involves anti-Markovnikov addition of the 1-alkene to the surface of the Si NPs., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Published
2015
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25. From gold porphyrins to gold nanoparticles: catalytic nanomaterials for glucose oxidation.

Author

Elouarzaki K, Le Goff A, Holzinger M, Agnès C, Duclairoir F, Putaux JL, and Cosnier S

Abstract

Au(iii) porphyrin was synthesized and evaluated for electrocatalytic oxidation of glucose. These Au(III) porphyrins, immobilized on a multiwalled carbon nanotube matrix, oxidized glucose at low overpotentials. Furthermore, AuNPs were electrogenerated by reduction of the Au(III) porphyrins. The electrocatalytic properties of these compounds towards glucose oxidation were compared and characterized by electrochemistry, electron microscopy and XPS.

Published
2014
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26. Highly stable tetrathiafulvalene radical dimers in [3]catenanes.

Author

Spruell JM, Coskun A, Friedman DC, Forgan RS, Sarjeant AA, Trabolsi A, Fahrenbach AC, Barin G, Paxton WF, Dey SK, Olson MA, Benítez D, Tkatchouk E, Colvin MT, Carmielli R, Caldwell ST, Rosair GM, Hewage SG, Duclairoir F, Seymour JL, Slawin AM, Goddard WA 3rd, Wasielewski MR, Cooke G, and Stoddart JF

Subjects
Dimerization, Catenanes chemistry
Abstract

Two [3]catenane 'molecular flasks' have been designed to create stabilized, redox-controlled tetrathiafulvalene (TTF) dimers, enabling their spectrophotometric and structural properties to be probed in detail. The mechanically interlocked framework of the [3]catenanes creates the ideal arrangement and ultrahigh local concentration for the encircled TTF units to form stable dimers associated with their discrete oxidation states. These dimerization events represent an affinity umpolung, wherein the inversion in electronic affinity replaces the traditional TTF-bipyridinium interaction, which is over-ridden by stabilizing mixed-valence (TTF)2•+ and radical-cation (TTF•+)2 states inside the 'molecular flasks.' The experimental data, collected in the solid state as well as in solution under ambient conditions, together with supporting quantum mechanical calculations, are consistent with the formation of stabilized paramagnetic mixed-valence dimers, and then diamagnetic radical-cation dimers following subsequent one-electron oxidations of the [3]catenanes.

Published
2010
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27. Porphyrin anchoring on Si(100) using a beta-pyrrolic position.

Author

Liu H, Duclairoir F, Fleury B, Dubois L, Chenavier Y, and Marchon JC

Abstract

Nickel(II) beta-azido-meso-tetraphenylporphyrin was successfully anchored on silicon using a bifunctional linker that bears two terminal alkyne functions by the sequence (i) hydrosilylation of a C[triple bond]C triple bond of the linker by surface Si-H groups and (ii) 1,3-Huisgen cycloaddition between the alkyne-terminated silicon surface and the azidoporphyrin derivative.

Published
2009
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28. Ferrocene and porphyrin monolayers on Si(100) surfaces: preparation and effect of linker length on electron transfer.

Author

Huang K, Duclairoir F, Pro T, Buckley J, Marchand G, Martinez E, Marchon JC, De Salvo B, Delapierre G, and Vinet F

Subjects
Electric Capacitance, Electron Transport, Metallocenes, Microelectrodes, Oxidation-Reduction, Potentiometry, Spectrometry, X-Ray Emission, Spectroscopy, Fourier Transform Infrared, Surface Properties, Ferrous Compounds chemistry, Porphyrins chemistry, Silicon chemistry
Abstract

The missing link: Ferrocene and porphyrin monolayers are tethered on silicon surfaces with short (see picture, left) or long (right) linkers. Electron transfer to the silicon substrate is faster for monolayers with a short linker.Ferrocene and porphyrin derivatives are anchored on Si(100) surfaces through either a short two-carbon or a long 11-carbon linker. The two tether lengths are obtained by using two different grafting procedures: a single-step hydrosilylation is used for the short linker, whereas for the long linker a multistep process involving a 1,3-dipolar cycloaddition is conducted, which affords ferrocene-triazole-(CH(2))(11)-Si or Zn(porphyrin)-triazole-(CH(2))(11)-Si links to the surface. The modified surfaces are characterized by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Cyclic voltammetry experiments show that the redox activity of the tethered ferrocene or porphyrin is maintained for both linker types. Microelectrode capacitor devices incorporating these modified Si(100) surfaces are designed, and their capacitance-voltage (C-V) and conductance-voltage (G-V) profiles are investigated. Capacitance and conductance peaks are observed, which indicates efficient charge transfer between the redox-active monolayers and the electrode surface. Slower electron transfer between the ferrocene or porphyrin monolayer and the electrode surface is observed for the longer linker, which suggests that by adjusting the linker length, the electrical properties of the device, such as charging and discharging kinetics and retention time, could be tuned.

Published
2009
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29. The first redox controlled hydrogen bonded three-pole switch.

Author

Bourgel C, Boyd AS, Cooke G, de Cremiers HA, Duclairoir FM, and Rotello VM

Abstract

The first example of a redox controlled hydrogen bonded three-pole switch is described, which exploits both electrochemical oxidation and reduction of the host-guest dyad to modulate the intermolecular recognition properties.

Published
2001
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