A5012935708- Radical Photochemical Reactions
- Magnetic properties of thin films
- Advanced Photocatalysis Techniques
- Synthetic Organic Chemistry Methods
- Sulfur-Based Synthesis Techniques
- Catalytic C–H Functionalization Methods
- Oxidative Organic Chemistry Reactions
- Cyclopropane Reaction Mechanisms
- Asymmetric Synthesis and Catalysis
- Magnetic Properties and Applications
- Polyoxometalates: Synthesis and Applications
- Asymmetric Hydrogenation and Catalysis
- Theoretical and Computational Physics
- Chemical Synthesis and Reactions
- Crystallization and Solubility Studies
- Physics of Superconductivity and Magnetism
- X-ray Diffraction in Crystallography
- Catalytic Processes in Materials Science
- Chemical Synthesis and Analysis
- Mesoporous Materials and Catalysis
- Chemical synthesis and alkaloids
- Catalytic Cross-Coupling Reactions
- Electrocatalysts for Energy Conversion
- Chemical Reactions and Isotopes
- Magnetic and transport properties of perovskites and related materials
Université de Haute-Alsace
2019-2025
Centre National de la Recherche Scientifique
2011-2024
Université de Strasbourg
2019-2024
Laboratoire d'innovation moléculaire et applications
2019-2023
Technion – Israel Institute of Technology
2017-2023
Laboratoire COBRA
2014-2022
Normandie Université
2017-2022
Université de Bordeaux
2019-2021
Institut des Sciences Moléculaires
2019-2021
ORCID
2021
We report on magnetic domain-wall velocity measurements in ultrathin Pt/Co(0.5-0.8 nm)/Pt films with perpendicular anisotropy over a large range of applied fields. The complete velocity-field characteristics are obtained, enabling an examination the transition between thermally activated creep and viscous flow: motion regimes predicted from general theories for driven elastic interfaces weakly disordered media. dissipation limited flow regime is found to be consistent precessional motion,...
We present an analytical calculation of the velocity a single 180 degree domain wall in magnetic structure with reduced thickness and/or lateral dimension under combined action external applied field and electrical current. As for case field-induced propagation thick films, two motion regimes different mobilities are obtained, below far above so-called Walker field. Additionally, current induced motion, Walker-like density threshold can be defined. When dimensions system become comparable to...
Cyanines are organic dyes bearing two aza-heterocycles linked by a polymethine chain.
Direct metal-free near infra-red photoredox catalysis is applied to oxidation, reduction and photosensitization, involving cyanines as photocatalysts. Mechanistic insights through kinetic quenching experiments are also reported.
Near-Infrared photoredox catalysis is now consider as the next evolution of this field.
Abstract The photocatalysis is a powerful tool in organic synthesis to generate reactive intermediates and create challenging chemical bonds. reactivity on such process mainly controlled by photocatalyst (PCat) which designed ensure both selectivity efficiency. In the pursuit of more economical environmentally friendly approaches, heterogenization photocatalysts has become increasingly essential, it still challenging. Among various insoluble supports studied, polymers offer several appealing...
The effect of electrical current pulses on magnetic domain walls is studied in a nanometer-scale track defined ${\text{He}}^{+}$-irradiated Pt/Co(0.5 nm)/Pt film with out-of-plane anisotropy. Current wide range intensities and durations are shown to result either demagnetization, or polarity-independent domain-wall propagation, due Joule heating during the pulse. None expected spin transfer effects occur. To explain this, spin-dependent current-density distribution stack evaluated, frame an...
The dynamics of the demagnetization induced by an ultrashort laser pulse in GdCo and GdCoFe alloys is shown to be substantially different from expected trend. We find that intersublattice exchange interaction between Gd Co(Fe) used as additional route heat transfer during process leads a temporary cooling spin subsystem. observed results are described four-temperature model (4T model) which electrons, lattice, 4$f$ 3$d$ spins represent four reservoirs energy. In this model, coupling electron...
Using 100 fs laser pulses, a high-frequency exchange and low-frequency ferromagnetic resonance mode have been excited detected in an amorphous ${\mathrm{Gd}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x}$ ($78\ensuremath{\le}x\ensuremath{\le}85$) ferrimagnetic thin film, on both sides of its angular momentum compensation composition. The excitation efficiency these modes strongly depends the amount laser-induced heating. Ways selectively efficiently exciting either one or two coexisting magnetic by...
The transformation of light into chemical energy is a leitmotiv in the development sustainable and environmentally concerned processes. Chemists invented original concepts to address this purpose, like photoredox catalysis, which became wonderful tool transform simple organic compounds high‐value products. Nevertheless, most relevant transition metal based photocatalysts suffer from major disadvantages toxicity, cost, poor recyclability potential. To circumvent this, we propose new...
Herein, unprecedented uses of squaraine derivatives as new organic near-infrared photocatalysts are reported. These efficient molecular tools able to promote oxidation and reduction for transformations through photocatalytic conditions. A mechanistic investigation is performed distinguish between competitive Single Electron Transfer Energy pathways.
Heterogenization of the photocatalyst appears to be a valuable solution reach sustainable processes. Rapid and efficient synthesis supported is still remaining challenge choice support material crucial. The present study aims at preparing new generation hybrid inorganic/organic photocatalysts based on silica mesoporous Eosin Y. These results highlight influence non-covalent interactions between reagent impacting selectivity reaction.
A second generation of cyanine-based near-infrared photocatalysts has been developed to accelerate organic transformations. Cyanines were prepared and fully characterized prior evaluation their photocatalytic activities. Catalyst efficiency was determined by using two model oxidation reduction reactions. For the aza-Henry reaction, cyanines bearing an amino group on heptamethine chain led best results. trifluoromethylation, stability photocatalyst found be key parameter for efficient rapid...
The domino anionic fragmentation of 2-nitrophenyl-1,3-cyclohexanediones containing an electrophilic appendage such as aldehyde and epoxide is disclosed. This reaction, initiated by a series nucleophiles, involves the generation intermediate hydroxylate followed regioselective formation lactolate into enolate. strategy, devoid any protecting group, enlarges initial ring provides original access to decorated 9-membered lactones with fused indole unit.
Heterogenization of Eosin Y by 3D-printing and its application in photocatalysis are reported. The approach allows a fine tuning the photocatalyst morphology rapid preparation. Photocatalytic activity was evaluated through model organic reactions involving oxidation, reduction, photosensitization pathways. efficiency, recyclability stability 3D printed EY is remarkable paving way to new generation heterogeneous photocatalysts with perfect control their shape adaptable any photoreactors.
Abstract Herein, the preparation and characterization of three Ru-based heterogeneous photocatalysts supported on ordered mesoporous silica materials are reported. The photocatalytic activity these catalysts was evaluated through oxidation, reduction, cycloaddition, carboxylation reactions their efficiencies comparable to parent [Ru(bpy)3]Cl2 under homogeneous conditions. These efficiently recovered even after five reaction cycles offering new opportunities in sustainable chemistry.
The regeneration of redox photocatalysts usually requires the use sacrificial reagents that are added to medium in stoichiometric amounts, either as an electron donor or acceptor, act relay photocatalyst ensure its effective regeneration. In present work, we consider possibility direct electrochemical catalyst using a model system made tris(2,2′-bipyridine)ruthenium(II) ([Ru(bpy)3]2+) photosensitizer and methylviologen (MV2+) quenching substrate. Based on hydrodynamic amperometry...
Trialkylaluminum compounds perform a diastereoselective 1,6-ring fragmentation of alkenylcyclopropane. This new tool allows the preparation hydrocarbon containing two distant stereocenters with good diastereocontrol. Inspired by biosynthesis botryococcene this methodology was applied successfully to diastereo- and enantioselective triterpene its epimer.
A new high resolution polar magneto-optical (MO) Kerr magnetometer, devoted to the study of nanometer sized elements with perpendicular magnetic anisotropy, is described. The unique performances this setup in terms sensitivity (1.2x10(-15) emu), stability (lateral drift +/-35 nm over 3 h), and (laser spot full width at half maximum down 470 nm) are demonstrated, illustrated by hysteresis loop measurements on a ultrathin nanodot, small segments ultranarrow tracks. Large scanning MO microscopy...
A metal-free procedure is described for the aerobic and complete C–H methylene oxidation of Hajos–Parrish enones to versatile dihydroindenediones.
We report on the electric control of magnetic anisotropy in an ultrathin ferromagnetic (Ga,Mn)As/(Ga,Mn)(As,P) bilayer with competing in-plane and out-of-plane anisotropies. The carrier distribution therefore strength effective are controlled by gate voltage a field effect device. Anomalous Hall measurements confirm that depletion carriers upper (Ga,Mn)As layer results decrease anisotropy. uniaxial is found to factor ∼4 over explored gate-voltage range so transition easy-axis configuration...