Publications

2019

• Anisotropy of Assemblies of Densely Packed Co-Alloy Nanoparticles Embedded in Carbon Nanotubes
  
  • Prischepa Serghej L
  • Danilyuk Alexander L
  • Kukharev Andrei V
  • Cojocaru Costel Sorin
  • Kargin Nikolai I
  • Le Normand François
  IEEE Magnetics Letters, IEEE, 2019, 10, pp.1-5. We report on the magnetic properties of an array of binary metal CoFe, CoNi, and CoPt nanoparticles (NPs) embedded inside vertically oriented carbon nanotubes (CNTs). Samples were synthesized by chemical vapor deposition activated by current discharge plasma and hot filaments. Assemblies of Co-based catalytic NPs were prepared on SiO 2 /Si substrates by sputtering ultrathin films followed by reduction in an H 2 /NH 3 mixture. As a result of the CNT growth, each CNT contained only one ferromagnetic NP located at the top. For all samples, the easy axis of magnetization was along the CNT axis. The magnetic parameters, including effective anisotropy constant and the contributions of dipole interactions and shape, magnetocrystalline, and magnetoelastic anisotropies, were estimated based on the experimental data and a random-anisotropy model. The magnetoelastic contribution was decisive. From the magnetoelasticity, the stresses in the NPs embedded in the CNTs were determined. Finally, the magnetization distribution in CoFe, CoNi, and CoPt NPs was simulated considering the magnetoelastic contribution. (10.1109/LMAG.2019.2933380)
  DOI : 10.1109/LMAG.2019.2933380
• Graphene Nanoplatelets Coating for Corrosion Protection of Aluminum Substrates
  
  • Bouanis Fatima Zahra
  • Moutoussammy Prisca
  • Florea Ileana
  • Dominique Nadia
  • Chaussadent Thierry
  • Pribat Didier
  Corrosion, National Association of Corrosion Engineers, 2019, 75 (7), pp.799-808. In this work, we study the properties of re-assembled graphene nanoplatelets as an effective anticorrosion coating for aluminum (Al) substrate in 0.5 M Sodium Chloride (NaCl) at room temperature (30°C). Scanning and Transmission Electron Microscopy (TEM) as well as Raman spectroscopy reveal the high quality multilayer graphene nanoplatelets. The modifications of the corrosion resistance characteristic were investigated by Open Circuit Potential (OCP), followed by electrochemical tests such as potentiodynamic polarization (Tafel curves) and Electrochemical Impedance Spectroscopy (EIS). The electrochemical results show that the graphene nanoplatelets provide effective resistance against the corrosive medium during the two weeks of immersion in the saline medium. Scanning Electron Microscopy (SEM), Raman spectroscopy and Energy Dispersive X-ray (EDX) studies carried out after immersion in the corrosive medium confirm that a graphene-coated aluminum surface is well protected compared to an uncoated substrate. (10.5006/2960)
  DOI : 10.5006/2960
• Experimental and numerical investigation of the transient charging of a dielectric surface exposed to a plasma jet
  
  • Slikboer Elmar
  • Viegas Pedro
  • Bonaventura Z.
  • Garcia-Caurel Enric
  • Sobota Ana
  • Bourdon Anne
  • Guaitella Olivier
  Plasma Sources Science and Technology, IOP Publishing, 2019, 28 (9), pp.095016. This work investigates the dynamical charging of a surface under exposure of a non-equilibrium plasma jet at atmospheric pressure through a quantitative comparison between modeling and experiments. We show using mono-polar pulses with variable pulse duration and amplitude that the charging time (i.e. the time from impact of the ionization wave till the fall of the high voltage pulse) is a crucial element determining the plasma-surface interaction. This is done through direct measurements of the electric field induced inside the target using the optical diagnostic technique called Mueller polarimetry and comparison with the electric field calculated using a 2D fluid model of the plasma jet interaction with the target in the same conditions as in the experiments. When the charging time is kept relatively short (less than 100 ns), the surface spreading of the discharge and consequent surface charge deposition are limited. When it is relatively long (up to microseconds), the increased surface spreading and charge deposition significantly change the electric field to which the target is exposed during the charging time and when the applied voltage returns to zero. (10.1088/1361-6595/ab3c27)
  DOI : 10.1088/1361-6595/ab3c27
• Optical chemosensors for metal ions in aqueous medium with polyfluorene derivatives: Sensitivity, selectivity and regeneration
  
  • Wang Xinyang
  • Lin Qiqiao
  • Ramachandran Sasikumar
  • Pembouong Gaëlle
  • Pansu Robert Bernard
  • Leray Isabelle
  • Lebental Bérengère
  • Zucchi Gaël
  Sensors and Actuators B: Chemical, Elsevier, 2019, 286, pp.pp.521-532. Six polyfluorene derivatives, P1-P6, were synthesized and investigated as responsive materials for the optical sensing of metal ions in an aqueous medium. They were designed by combining carbazole with fluorene units within the backbone. Carbazole was N-functionalized with three coordinating groups, 2-pyridyl-benzimidazole (P1 and P4), 2-phenyl-benzimidazole (P2 and P5) and 4-phenyl-terpyridyl (P3 and P6), respectively. P1-P3 are random copolymers with fluorene:carbazole ratios of 9:1 for P1 and P2, and 9.7:0.3 for P3; P4-P6 are the corresponding alternating polymers. This design lead to polymers made of a conjugated backbone and pendant coordinating groups. The optical properties of the monomers were impacted in various ways by metal ions, and the formation of the [NiM3]2+ and [ZnM3]2+ and [ZnM32]2+ were evidenced with association constants of 105.22, 106.45 and 1014.0, respectively. The emission of the polymers was afterwards found to be influenced by theses metal ions with different sensitivity and selectivity. P1 was found to be more sensitive to the Ni2+ and Cu2+ ions with a better selectivity for Ni2+. Emission of the corresponding alternating polymer P4 was more efficiently quenched by these two ions with respect to P1, in addition of being sensitive to the Ca2+ and Al3+ ions. P3 showed sensitivity to the Ni2+, Cu2+, Al3+, Ca2+, and Zn2+ ions. The luminescence of P6 was much more pronounced with the Ni2+, Cu2+, Cd2+, Zn2+, Al3+, Fe2+, and Fe3+ ions with respect to P3. More remarkably, the presence of the Zn2+ or Cd2+ ions resulted in a new emission band, leading to the possibility to selectively sense these two ions. Relatively high Stern-Volmer constants (in the 106-105 range) were obtained, and sensitivities down to the ppb level were reached, especially for the Ni2+ ion. Influence of both the coordinating group and the polymer backbone on the polymers sensitivity and selectivity was emphasized. Finally, the recyclability of some representative optical sensors was shown both in solution and in the solid state. In particular, thin films were shown to be easily regenerated, which opens the way to the elaboration of reusable optical sensors. (10.1016/j.snb.2019.01.013)
  DOI : 10.1016/j.snb.2019.01.013
• Completing an experimental nondepolarizing Mueller matrix whose column or row is missing Completing an experimental nondepolarizing Mueller matrix whose column or row is missing
  
  • Ossikovski Razvigor
  • Arteaga Oriol
  Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures, American Vacuum Society (AVS), 2019, 37. The authors report on an algebraic procedure, allowing for the completion of an experimental nondepolarizing Mueller matrix with a column or a row missing to a full 16-element one. The method provides a closed-form solution for the missing column or row and is illustrated on single-wavelength, spectroscopic, and imaging experimental examples. Published by the AVS. (10.1116/1.5120342)
  DOI : 10.1116/1.5120342
• Snapshot circular dichroism measurements
  
  • Arteaga Oriol
  • El-Hachemi Zoubir
  • Ossikovski Razvigor
  Optics Express, Optical Society of America - OSA Publishing, 2019. Two coherent waves carrying orthogonal polarizations do not interfere when they superpose, but an interference pattern is generated when the two waves share a common polarization. This well-known principle of coherence and polarization is exploited for the experimental demonstration of a novel method for performing circular dichroism measurements whereby the visibility of the interference fringes is proportional to the circular dichroism of the sample. Our proof-of-concept experiment is based upon an analog of Young's double-slit experiment that continuously modulates the polarization of the probing beam in space, unlike the time modulation used in common circular dichroism measurement techniques. The method demonstrates an accurate and sensitive circular dichroism measurement from a single camera snapshot, making it compatible with real-time spectroscopy. (10.1364/OE.27.006746)
  DOI : 10.1364/OE.27.006746
• Molecular Beam Epitaxy of Germanium in the Atomic-Resolution Transmission Electron Microscope
  
  • Ngo Eric
  • Panciera Federico
  • Harmand Jean-Christophe
  • Wang Weixi
  • Foldyna Martin
  • I Cabarrocas Pere Roca
  • Travers Laurent
  • Florea Ileana
  • Maurice Jean-Luc
  Microscopy and Microanalysis, Cambridge University Press, 2019, 25 (S1), pp.47-48. (10.1017/S1431927618015969)
  DOI : 10.1017/S1431927618015969
• Enhancement of the capacitance properties and the photoelectrochemical performances of P3HT film by incorporation of nickel oxide nanoparticles
  
  • Ghalmi Yasser
  • Habelhames Farid
  • Sayah Abdelfetteh
  • Bahloul Ahmed
  • Nessark Balkacem
  • Derbal-Habak Hassina
  • Bonnassieux Yvan
  • Nunzi Jean-Michel
  Ionics, Springer Verlag, 2019, 25 (6), pp.2903-2912. P3HT films were modified by incorporation of different amounts of nickel oxide (NiO). The nickel oxide powder was synthesized by chronoamperometry. The composites were further dissolved and deposited by the spin-coating method on indium-tin oxide (ITO) substrates. Effects of NiO content on the morphology structure and optical properties of P3HT films were investigated by means of XRD, SEM, AFM, and UV-Vis spectroscopy. Electrochemical and photoelectrochemical performances were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), galvanostatic charge-discharge, and photocurrent measurements. Results show that NiO dispersed uniformly in P3HT thin films and modified the surface roughness and absorption of the deposited thin films. A remarkable improvement of photocurrent density and electrochemical capacitance is observed for an NiO content ranging between 1 and 10wt%. The specific capacitance obtained for P3HT alone is about 20.8Fg(-1), this value increases to 81.4Fg(-1)for the P3HT-NiO 10wt% composite film at 0.1-A/g current density. (10.1007/s11581-018-2781-2)
  DOI : 10.1007/s11581-018-2781-2
• Experimental studies of the transmission of light through low-coverage regular or random arrays of silica micropillars supported by a glass substrate
  
  • Turbil Colette
  • Yoo Thomas Sang Hyuk
  • Simonsen Ingve
  • Teisseire Jérémie
  • Gozhyk Iryna
  • Garcia-Caurel Enric
  Applied optics, Optical Society of America, 2019, 58 (33), pp.9267. (10.1364/AO.58.009267)
  DOI : 10.1364/AO.58.009267
• Experimental demonstration of multifrequency impedance matching for tailored voltage waveform plasmas
  
  • Wang Junkang
  • Diné Sébastien
  • Booth Jean-Paul
  • Johnson Erik
  Journal of Vacuum Science & Technology A, American Vacuum Society, 2019, 37 (2), pp.021303. Driving radiofrequency capacitively coupled plasmas by multiharmonic tailored voltage waveforms (TVWs) has been shown to allow considerable control over various plasma properties for surface processing applications. However, industrial adoption of this technology would benefit from more efficient solutions to the challenge of impedance matching the radiofrequency power source to the load simultaneously at multiple harmonic frequencies. The authors report on the design and demonstration of a simple, practical multifrequency matchbox (MFMB) based on a network of LC resonant circuits. The performance of the matchbox was quantified in terms of a range of matchable impedances (when matching a single frequency at a time), as well as for the independence of each match to changes at adjacent harmonics. The effectiveness of the MFMB was demonstrated experimentally on an Ar plasma excited by a three-frequency TVW with a fundamental frequency of 13.56 MHz. Under the plasma conditions studied, the power coupling efficiency (at the generator output) was increased from less than 40% (without impedance matching) to between 80% and 99% for the different exciting frequencies. (10.1116/1.5056205)
  DOI : 10.1116/1.5056205
• Ultra-sensitive NO2 gas sensors based on single-wall carbon nanotube field effect transistors: Monitoring from ppm to ppb level
  
  • Sacco Leandro
  • Forel Salomé
  • Florea Ileana
  • Cojocaru Costel-Sorin
  Carbon, Elsevier, 2019. Owing to their sensitive chemical-to-electrical transducer capabilities and compatibility with device miniaturization and low operation temperature, single-walled carbon nanotube field-effect transistor (SWCNT-FET) represents an attractive platform to provide solutions in the gas sensing field. In this work, SWCNT-FETs were fabricated and their performances for detecting low NO2 concentrations were evaluated. Outstanding devices response was obtained, which was shown to follow a 2 power law dependence between the response and the NO2 concentration in the range of 100 ppb up to 10 ppm. Such ultra-high response is attributed to an enhancement of the Schottky barrier modulation triggered by the specific device configuration. The device configuration is based on individual semiconducting SWCNTs directly connecting the interdigitated Source-Drain electrodes. To the best of our knowledge, the results reported here correspond to the most sensitive device among the devices based on non-functionalized carbon materials and operational at low temperatures. Furthermore, the obtained results are supported by a deep SWCNT characterization, and the changes in Schottky barrier's height induced by the presence of gas molecules are estimated and discussed. Overall, the present reported results provide useful information for establishing a robust process for the fabrication of the next generation of CNT based gas-sensing devices. (10.1016/j.carbon.2019.10.073)
  DOI : 10.1016/j.carbon.2019.10.073
• Complete Mueller matrix from a partial polarimetry experiment: the nine-element case
  
  • Ossikovski Razvigor
  • Arteaga Oriol
  Journal of the Optical Society of America. A Optics, Image Science, and Vision, Optical Society of America, 2019. We show that an incomplete, nine-element Mueller matrix with a row and a column missing, obtained in a partial polarimetry experiment, can be completed to a full, 16-element Mueller matrix, provided depolarization is absent experimentally. There exist exactly two solutions for the missing row and column, differing from one another only by the signs of the respective row and column elements. To select the correct solution, additional information on the sample properties, such as weak anisotropy or special symmetry, is needed. We provide analytical and numerical procedures for completing the partial Mueller matrix for the cases of practical interest and illustrate the approach on an experimental example. (10.1364/JOSAA.36.000403)
  DOI : 10.1364/JOSAA.36.000403
• Photocatalytic activity of ZnO nanopowders: The role of production techniques in the formation of structural defects
  
  • Danilenko I.
  • Gorban O.
  • Maksimchuk P.
  • Viagin O.
  • Malyukin Y.
  • Gorban S.
  • Volkova G.
  • Glasunova V.
  • Mendez-Medrano M. G.
  • Colbeau-Justin Christophe
  • Konstantinova T.
  • Lyubchyk S.
  Catalysis Today, Elsevier, 2019, 328, pp.99-104. (10.1016/j.cattod.2019.01.021)
  DOI : 10.1016/j.cattod.2019.01.021
• Stern-Gerlach experiment with light: separating photons by spin with the method of A. Fresnel
  
  • Arteaga Oriol
  • Garcia-Caurel Enric
  • Ossikovski Razvigor
  Optics Express, Optical Society of America - OSA Publishing, 2019. In 1822 A. Fresnel described an experiment to separate a beam of light into its right-and left-circular polarization components using chiral interfaces. Fresnel's experiment combined three crystalline quartz prisms of alternating handedness to achieve a visible macroscopic separation between the two circular components. Such quartz polyprisms were rather popular optical components in XIXth century but today remain as very little known optical devices. This work shows the analogy between Fresnel's experiment and Stern-Gerlach experiment from quantum mechanics since both experiments produce selective deflection of particles (photons in case of Fresnel's method) according to their spin angular momentum. We have studied a historical quartz polyprism with eight chiral interfaces producing a large spatial separation of light by spin. We have also constructed a modified Fresnel biprism to produce smaller separations and we have examined the analogy with Stern-Gerlach apparatus for both strong and weak measurements. The polarimetric analysis of a Fresnel polyprism reveals that it acts as a spin angular momentum analyzer. (10.1364/OE.27.004758)
  DOI : 10.1364/OE.27.004758
• Anisotropic integral decomposition of depolarizing Mueller matrices
  
  • Ossikovski Razvigor
  • Kuntman Ali
  • Arteaga Oriol
  OSA Continuum, OSA Publishing, 2019. We propose a novel, computationally efficient integral decomposition of depolarizing Mueller matrices allowing for the obtainment of a nondepolarizing estimate, as well as for the determination of the elementary polarization properties, in terms of mean values and variances-covariances of their fluctuations, of a weakly anisotropic depolarizing medium. We illustrate the decomposition on experimental examples and compare its performance to those of alternative decompositions. (10.1364/OSAC.2.001900)
  DOI : 10.1364/OSAC.2.001900
• Aggregate-driven reconfigurations of carbon nanotubes in thin networks under strain: in-situ characterization
  
  • Bodelot Laurence
  • Pavic Luka
  • Hallais Simon
  • Charliac Jérôme
  • Lebental Bérengère
  Scientific Reports, Nature Publishing Group, 2019, pp.11p. This work focuses on the in-situ characterization of multi-walled carbon nanotube (CNT) motions in thin random networks under strain. Many fine-grain models have been devised to account for CNT motions in carbon nanotube networks (CNN). However, the validation of these models relies on mesoscopic or macroscopic data with very little experimental validation of the physical mechanisms actually arising at the CNT scale. In the present paper, we use in-situ scanning electron microscopy imaging and high resolution digital image correlation to uncover prominent mechanisms of CNT motions in CNNs under strain. Results show that thin and sparse CNNs feature stronger strain heterogeneities than thicker and denser ones. It is attributed to the complex motions of individual CNTs connected to aggregates within thin and sparse CNNs. While the aggregates exhibit a collective homogeneous deformation, individual CNTs connecting them are observed to fold, unwind or buckle, seemingly to accommodate the motion of these aggregates. In addition, looser aggregates feature internal reconfgurations via cell closing, similar to foam materials. Overall, this suggests that models describing thin and sparse CNN deformation should integrate multiphase behaviour (with various densities of aggregates in addition to individual CNTs), heterogeneity across surface, as well as imperfect substrate adhesion. (10.1038/s41598-019-41989-2)
  DOI : 10.1038/s41598-019-41989-2
• Erratum: Multi frequency matching for voltage waveform tailoring <A href="/abs/">(2018 Plasma Sources Sci. Technol. 27 095012</A>)
  
  • Schmidt Frederik
  • Schulze Julian
  • Johnson Erik
  • Booth Jean-Paul
  • Keil Douglas
  • French David M.
  • Trieschmann Jan
  • Mussenbrock Thomas
  Plasma Sources Science and Technology, IOP Publishing, 2019, 28, pp.019601. (10.1088/1361-6595/aaeb4b)
  DOI : 10.1088/1361-6595/aaeb4b