A5052444248- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Glass properties and applications
- Laser-Ablation Synthesis of Nanoparticles
- Photonic Crystals and Applications
- Silicon Nanostructures and Photoluminescence
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanowire Synthesis and Applications
- Luminescence Properties of Advanced Materials
- Gas Sensing Nanomaterials and Sensors
- Mesoporous Materials and Catalysis
- Copper-based nanomaterials and applications
- Nonlinear Optical Materials Studies
- Aerogels and thermal insulation
- Photonic and Optical Devices
- Cultural Heritage Materials Analysis
- Semiconductor materials and devices
- Semiconductor Quantum Structures and Devices
- Solid-state spectroscopy and crystallography
- Catalysis and Oxidation Reactions
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced NMR Techniques and Applications
- Semiconductor materials and interfaces
- Pigment Synthesis and Properties
- Analytical Chemistry and Sensors
Université de Lille
2010-2019
Centre National de la Recherche Scientifique
2006-2018
Laboratoire de Physique des Lasers, Atomes et Molécules
2010-2018
École Centrale de Lille
2016
Institut d'électronique de microélectronique et de nanotechnologie
2016
Institut de Recherche sur les Composants logiciels et matériels pour l'Information et la Communication Avancée
2011-2016
Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement
2006-2010
Istituto di Fotonica e Nanotecnologie
2010
École Nationale Supérieure de Chimie de Lille
2010
Nello Carrara Institute of Applied Physics
2010
Buried truth: High-field magic angle spinning dynamic nuclear polarization (MAS DNP) enhances the sensitivity of solid-state NMR spectroscopy, but only for protonated surfaces. Direct 29Si DNP using biradical TOTAPOL (see picture) circumvents this limitation by producing a 30-fold enhancement subsurface signals in mesoporous silica, material with applications photonics, nanotechnology and catalysis. Detailed facts importance to specialist readers are published as "Supporting Information"....
We report on the sol-gel fabrication and characterization of (100−x)SiO2–xSnO2 (x=8, 16, 25mol%) glass-ceramic waveguides doped with 1mol% Eu3+. A suitable top-down thermal process led to formation SnO2 nanocrystals ∼4nm embedding Eu3+ ions. The excitation spectra evidence role interband electronic transition luminescence Monitoring D05→F27 emission, we observe about 15 times increase in intensity absorption band, moving from x=8to25mol%. These also exhibit low losses, making them quite...
Surface nanostructuration is an important challenge for the optimization of light trapping in solar cell. We present simulations on both optical properties and efficiency micro pillars—MPs—or nanocones—NCs—silicon based cells together with measurements their associated absorption. address simulation using Finite Difference Time Domain method, well-adapted to deal a periodic set nanostructures. study effect period, bottom diameter, top height MPs or NCs efficiency, assuming that one absorbed...
We report on the fabrication of Eu3+-doped SiO2−SnO2 low-loss (0.8 dB/cm at 632.8 nm) glass-ceramic planar waveguides, fabricated by sol−gel technique and dip-coating processing. The effects heat treatments growth evolution SnO2 nanocrystals in matrix were investigated using different spectroscopic tools. In situ high-temperature X-ray diffraction allowed for determination crystallization temperature confirmed formation tetragonal rutile crystals. effect optical properties photoluminescence...
Crack‐free (100– x ) SiO 2 – SnO glass‐ceramic monoliths have been prepared by the sol–gel method obtaining for first time concentrations of 20% with annealing at 1100 °C. Heat‐treatment resulted in formation and growth nanocrystals within silica matrices. Combined use Fourier transform–Raman spectroscopy situ high‐temperature X‐Ray diffraction shows that particles begin to crystallize cassiterite‐type phase 80 °C their average apparent size remains around 7 nm, even after Nanocrystal sizes...
We have investigated the diameter dependence of Raman spectra lead selenide nanocrystals. The first-order peak at about 136 cm${}^{\ensuremath{-}1}$ and its second-order overtone twice this wavenumber move up in energy with decreasing nanocrystal diameter. This anomalous behavior is interpreted terms quantum confinement longitudinal optical (LO) phonon whose frequency displays a minimum \ensuremath{\Gamma} dispersion bulk PbSe. perform ab initio calculations phonons PbSe slabs to 15 layers....
A new approach to dope a silica glass with gold nanoparticles (GNPs) is presented. It consisted in embedding zirconia-coated GNPs sol form doped gel. Then, the sol-doped nanoporous xerogel densified leading formation of monolith. The spectral position and shape surface plasmon resonance (SPR) reported around 520 nm remain compatible small spherical matrix. saturable absorption behavior this gold/zirconia-doped has been evidenced by Z-scan technique. second-order nonlinear coefficient β about...
Thin films of cadmium sulfide have been deposited from acidic solutions. The characterised by electronic, photoluminescence (PL) and X-ray photoelectron (XPS) spectroscopies, scanning transmission electron microscopy (SEM TEM) powder diffraction (XRD). as-deposited polycrystalline CdS are hexagonal, the crystallinity is improved annealing in air at 400 °C. procedure also leads to a concentration chloride surface films. Deposition baths may open up new simple synthetic routes towards ternary...
A new class of glass-ceramic nanocomposite systems with a uniform distribution SnO2 nanocrystals dispersed within an amorphous silica phase is fabricated in the form thin films by using sol–gel processing. In this work, experiments (100-x)SiO2-xSnO2 (x = 25 and 30 mol%) doped Er3+ ions (concentrations 0.5, 1 2 are presented. The focus has been both to determine effect rare-earth doping on growth as well ceramic structure. Vibrational spectroscopic assessments have proven nature samples....
Abstract In this study, optical microscopy and micro‐Raman spectroscopy were used to determine the chemical compositions of materials in preparatory pictorial layers wall paintings from four different sites Roman Empire first second century AD. The use UV excitation for Raman work study made it possible overcome problems fluorescence. fresco technique, revealed by presence calcite Greek samples, was not Gallo–Roman works. studies indicated that same compounds red green pigments throughout...
Ionic copper- or silver-doped dense silica rods have been prepared by sintering sol-gel porous xerogels doped with ionic precursors. The precipitation of Cu Ag nanoparticles was achieved heat treatment under hydrogen followed annealing air atmosphere. surface plasmon resonance bands copper and silver clearly observed in the absorption spectra. spectral positions these were found to depend slightly on particle size, which could be tuned varying conditions. Hence, transmission electron...
The first page of this article is displayed as the abstract.
Pulsed femtosecond laser irradiation at low repetition rate, without any annealing, has been used to localize the growth of PbS nanoparticles, for first time, inside a transparent porous silica matrix prepared by sol-gel route. Before irradiation, host soaked within solution containing precursors. The effect incident power on particle size was studied. X-ray diffraction identify crystallites irradiated areas and estimate average size. localized led crystallite ranging between 4 8 nm,...
Tiefenwirkung: Dynamische Kernpolarisation unter Rotation im magischen Winkel (MAS-DNP) in einem starken Magnetfeld erhöht die Empfindlichkeit der Festkörper-NMR-Spektroskopie, jedoch nur für protonierte Oberflächen. Direkte 29Si-DNP Verwendung des Diradikals TOTAPOL (siehe Bild) umgeht diese Einschränkung; sie verstärkt NMR-Signale von 29Si-Atomen Oberfläche mesoporösem Siliciumoxid um das 30fache.
Semiconductor PbSe/CdSe core-shell nanocrystals (NCs) in a double barrier tunnel junction have been investigated by means of scanning tunneling spectroscopy at low temperature. From the analysis differential conductance peak position as function potential distribution both barriers, we demonstrate unipolar transport regime for large amount NCs. The same charge carriers are injected on sides zero-conductance gap, and peaks observed higher energy arise from charging Similar results obtained...
The deposition of ternary materials such as Cd1 − xZxnS by chemical bath methods is a problem due to differing hydrolytic stabilities the two metals. A novel approach this material has been developed in which moderately acidic baths are used.