A5050196742- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Metal-Organic Frameworks: Synthesis and Applications
- Polyoxometalates: Synthesis and Applications
- Luminescence Properties of Advanced Materials
- Lanthanide and Transition Metal Complexes
- Gas Sensing Nanomaterials and Sensors
- Magnetism in coordination complexes
- ZnO doping and properties
- Transition Metal Oxide Nanomaterials
- Microwave Dielectric Ceramics Synthesis
- Photochromic and Fluorescence Chemistry
- Supramolecular Self-Assembly in Materials
- Inorganic Fluorides and Related Compounds
- Advanced Nanomaterials in Catalysis
- Advanced Condensed Matter Physics
- Crystallography and molecular interactions
- Ferroelectric and Piezoelectric Materials
- Photonic and Optical Devices
- Solid State Laser Technologies
- Nanocluster Synthesis and Applications
- Porphyrin and Phthalocyanine Chemistry
- Glass properties and applications
- Advanced Fiber Laser Technologies
- Magnetic and transport properties of perovskites and related materials
Centre National de la Recherche Scientifique
2015-2024
Institut des Matériaux Jean Rouxel
2015-2024
Nantes Université
2015-2024
Université de Bordeaux
2007-2016
Institut de Chimie de la Matière Condensée de Bordeaux
2009-2016
Chimie de la Matière Condensée de Paris
2011-2013
Chimie ParisTech
2011-2013
Laboratoire de Recherche Scientifique
2013
Max Planck Institute for Solid State Research
2010-2011
Sorbonne Université
2011
Abstract In the last decade, numerous Ln‐bearing metal‐organic frameworks (MOFs) have been reported for luminescence thermometry applications. Although Ln 3+ composition is always thoroughly determined, this parameter never optimized to improve thermometric performances. Here, optimization of performances luminescent probes tackled by reporting a series mixed Eu –Tb frameworks. The are accessed as function content yielding maximum relative sensitivity between 0.19 and 0.44% K −1 registered...
Novel melilite-type Ca2Ga2SiO7:Eu3+ red-emitting phosphors with different Eu3+ contents were synthesized via high-temperature solid-state reaction. The crystal structure, optical absorption, and photoluminescence properties investigated, while density functional theory calculations performed on the host lattice. excitation spectra indicate that can be effectively excited by near-UV light for a potential application in white-light-emitting diodes. Because of abnormally high intensity emission...
A temperature sensor based on lanthanide molecular species immobilized in a metal–organic framework exhibits high relative thermal sensitivity the physiological domain.
The first example of a dual-emitting luminescent thermometer based on lanthanide isophthalate exhibiting maximum relative sensitivity 3.26% K<sup>−1</sup>, temperature uncertainty 0.07 K at 35.5 K, and repeatability >99.9% between 12 230 K.
In the reported spiropyran/polyoxometalate/BODIPY triad, fluorescence of BODIPY can be highly reversibly quenched by activation photochromic spiropyran.
Polycrystalline yttrium iron garnet (Y3Fe5O12, hereafter labeled YIG) has been synthesized by solid-state reaction, characterized X-ray diffraction, Mössbauer spectroscopy, and UV–vis-NIR diffuse reflectance its optical properties from room temperature (RT) to 300 °C are discussed. Namely, greenish color at RT is assigned an O2– → Fe3+ ligand-to-metal charge transfer 2.57 eV coupled with d–d transitions peaking 1.35 2.04 eV. When the raised, YIG displays a marked thermochromic effect; i.e.,...
Abstract Six polyoxometalates containing Mn II , III or Fe as the heteroelement were synthesized in water by treating Mo VI precursors with biologically active bisphosphonates (alendronate (Ale), zoledronate (Zol), an n ‐alkyl bisphosphonate (BPC 9 ), aminoalkyl 8 NH 2 )) presence of additional metal ions. The Pt complex was from a polyoxomolybdate precursor ions linked 2‐pyridyl analogue alendronate (AlePy). complexes 4 Ale Mn, Zol Fe, ) and contain two dinuclear cores bound to central...
Samples of inverse spinel Mg2SnO4 were prepared using a ceramic method, their phosphorescence phenomenon was probed by optical measurements, and its cause explored on the basis density functional theory calculations for model structures with oxygen vacancies VO. exhibits long-lasting luminescence at two different wavelength regions, peaking ∼498 ∼755 nm. A Sn-VO-Sn defect plus Mg vacancy VMg away from VO generates empty midgap states, σSn-Sn σSn-Sn*, localized defect, while an between...
This paper reports a new strainless fabrication method for ytterbium‐doped CaF 2 laser ceramics involving no drying step before green body casting. The nanoparticles were kept in aqueous solution until shaping. Centrifugation was used to obtain correct compactness of the sintering. Characterizations conducted at different steps process. No grain boundaries oxidation observed sintered although permanently maintained water they sintered. Finally, these are more homogeneous and have less light...
Eu-Tb-UiO-66 acts as a highly sensitive luminescent thermometer near room temperature.
The luminescent [EuW10O36]9- polyoxometalate has been introduced into the cavities of highly porous zirconium metal-organic framework UiO-67 via a direct synthesis approach, affording EuW10@UiO-67 hybrid. Using combination techniques (TGA, BET, elemental analysis, EDX mapping,…) this new material fully characterized, evidencing that it contains only 0.25% in europium and units are located inside octahedral not at surface crystallites. Despite low amount europium, is shown acts as solid-state...
Design of a new highly sensitive cryogenic luminescent thermometer based on mixed Eu/Tb MOF.
Abstract An initial investigation on the employment of targeted structural alterations, achieved through post‐synthesis modification method, for modulation thermometric properties metal–organic frameworks (MOFs) is reported. The MOF Eu 0.05 Tb 0.95 ‐NBDC (NBDC = 2‐amino‐1,4‐benzenedicarboxylate) chosen as pristine material, and its terminal N , ‐dimethylformamide (DMF) molecules are exchanged by various chelating ligands a single‐crystal‐to‐single‐crystal coordinating solvent exchange...
Macroscopic vanadium oxide fibers have been fabricated by an extrusion process. By varying the shear rate associated with gel process we able to tune diameter and transversal geometry of at macroscopic length scales. At mesoscopic scale, small-angle X-ray scattering (SAXS) analysis provides evidence for possibility fine tuning degree alignment V2O5 ribbons inside fibers; this is clearly improved upon increasing rate. Nitrogen physisorption measurements (Brunauer–Emmett–Teller (BET)) indicate...
A promising general approach is proposed that enables the controlled reduction of dopants to tune photoluminescence properties single-phase materials. The change oxidation state in phosphor phases leads different emission colors can be finely tuned. This was illustrated with progressive red SrAl2O4:Eu(3+) green SrAl2O4:Eu(2+) target yellow luminescence.
We demonstrate that the solid-state luminescence of an organic molecular switch can be governed by its grafting to polyoxometalate units.
Two sets of Ga-doped ZnO powders were synthesized via solid-state and Pechini routes with a substitution rate varying from 0 to 4 mol %. The gallium solubility limit is strongly dependent on the synthesis history. Indeed, low temperature annealing allows incorporating about 1.5 % (X-ray diffraction (XRD), inductive coupled plasma spectroscopy (ICP), optical properties) whereas under 0.1% dopant introduced after thermal treatment at high temperature: 1500 °C (from XRD pellets conductivity)....
Novel photochromic polymers highlight through their solid-state optical properties the key role of grafting onto coloration and fading kinetics.
Abstract Two new supramolecular fluorescent hybrid materials, combining for the first time [M 6 O 19 ] 2− (M=Mo, W) polyoxometalates (POMs) and aggregation‐induced emission (AIE)‐active 1‐methyl‐1,2,3,4,5‐pentaphenyl‐phospholium ( 1 + ), were successfully synthesized. This novel molecular self‐assembling strategy allows designing efficient solid‐state emitters, such as (1) 2 [W , by directing favorably balance between AIE aggregation‐caused quenching (ACQ) effects using both anion‐π...
We report herein a new catalytic strategy towards asymmetric photooxygenation of β‐dicarbonyl compounds. Our method is based on the synthesis bifunctional photosensitizer composed quinine organocatalyst grafted to an iodo‐BODIPY framework capable generating singlet oxygen. The moiety serves both interact with substrate for promoting and deactivate oxygen in absence substrate. prepared was subsequently applied oxygenation series compounds under green light irradiation. Control experiments...
New assemblies based on the archetypal [Ir<sup>III</sup>(ppy)<sub>2</sub>(bpy)]<sup>+</sup> complex and a series of polyoxometalates exhibit highly tunable phosphorescence vapoluminescence properties for detection volatile organic compounds.