Single crystals of CaWO(4) and CaMoO(4) doped with Tb(3+) have been grown by the flux growth meth... more Single crystals of CaWO(4) and CaMoO(4) doped with Tb(3+) have been grown by the flux growth method. Their luminescence properties have been investigated in the 10-600 K temperature range under different experimental conditions. In spite of very similar spectra at low temperature upon excitation at 365 nm, the crystals show a very different behavior as the temperature is raised or the excitation wavelength is changed. These differences have been accounted for on the basis of models that take into consideration the position of the energy levels of the rare earth relative to the bandgap of the host material.
This work focuses on the study of BaMgAl10O17:Eu(2+) (BAM:Eu) nanophosphors prepared by a microwa... more This work focuses on the study of BaMgAl10O17:Eu(2+) (BAM:Eu) nanophosphors prepared by a microwave-assisted combustion procedure and more especially on the polymer/BAM:Eu nanocomposite film suitable for optical devices such as solid-state-lighting. Powder presented a specific nanomorphology, highly friable and thus easily ground into fine particles. They were then homogeneously dispersed into a polymer solution (poly(N-vinylpyrrolidone) or PVP) to elaborate a polymer phosphor nanocomposite. The structural, morphological and optical features of the nanocomposite film have been studied and compared to those of a pristine PVP film and BAM:Eu powder. All the characterizations (XRD, SEM, SAXS, etc.) proved that the blue phosphor nanoparticles are well incorporated into the polymer nanocomposite film which exhibited the characteristic blue emission of Eu(2+) under UV light excitation. Furthermore, the photostability of the polymer/phosphor nanocomposite film has been studied after exposure to accelerated artificial photoageing at wavelengths above 300 nm.
4-Triazolyl-dipicolinic acids, prepared efficiently by CuAAC, proved to act as efficient antennae... more 4-Triazolyl-dipicolinic acids, prepared efficiently by CuAAC, proved to act as efficient antennae for optical lanthanide probes containing Eu(3+) or Tb(3+), under linear and non linear excitations (one, two and three photons provided by laser induced luminescence). The versatility offered by the substitution of the triazole subunit is, in addition, useful for covalent linkage to slide glass providing luminescent films.
... Luminescence Behavior of Sol−Gel-Derived Hybrid Materials Resulting from Covalent Grafting of... more ... Luminescence Behavior of Sol−Gel-Derived Hybrid Materials Resulting from Covalent Grafting of a Chromophore Unit to Different Organically Modified Alkoxysilanes. ... 1-2 The sol−gel technique has proven to be a convenient route for the preparation of such hybrid compounds. ...
... To achieve a resonant pumping in the blue wavelength range, that is, in the 5 D 2 manifold, t... more ... To achieve a resonant pumping in the blue wavelength range, that is, in the 5 D 2 manifold, the output of the dye laser was upshifted by 4155 cm - 1 by stimulated Raman scattering in a high-pressure gaseous H ... (1) Harmer, AL; Linz, A.; Gabbe, D.; Gillespie, L.; Janey, GM; Sharp ...
ABSTRACT Luminescent Tb3+ yttrium-based garnets powders have been prepared by the sol-gel route. ... more ABSTRACT Luminescent Tb3+ yttrium-based garnets powders have been prepared by the sol-gel route. Optical properties of samples have been studied. Excitation spectra have revealed several excitation bands between 200 and 500 nm, which match very well with newly developed AlGaN-based deep-ultraviolet (DUV) or near-UV LEDs. Excitation profiles are dependent on the matrix formula. Emission spectral features studied upon different UV excitation wavelength have revealed that luminescence efficiency can be significantly improved by tuning the matrix composition. Thus, optical properties can be tuned to optimize the lighting source features, according to the kind of UV LEDs employed.
Single crystals of CaWO(4) and CaMoO(4) doped with Tb(3+) have been grown by the flux growth meth... more Single crystals of CaWO(4) and CaMoO(4) doped with Tb(3+) have been grown by the flux growth method. Their luminescence properties have been investigated in the 10-600 K temperature range under different experimental conditions. In spite of very similar spectra at low temperature upon excitation at 365 nm, the crystals show a very different behavior as the temperature is raised or the excitation wavelength is changed. These differences have been accounted for on the basis of models that take into consideration the position of the energy levels of the rare earth relative to the bandgap of the host material.
This work focuses on the study of BaMgAl10O17:Eu(2+) (BAM:Eu) nanophosphors prepared by a microwa... more This work focuses on the study of BaMgAl10O17:Eu(2+) (BAM:Eu) nanophosphors prepared by a microwave-assisted combustion procedure and more especially on the polymer/BAM:Eu nanocomposite film suitable for optical devices such as solid-state-lighting. Powder presented a specific nanomorphology, highly friable and thus easily ground into fine particles. They were then homogeneously dispersed into a polymer solution (poly(N-vinylpyrrolidone) or PVP) to elaborate a polymer phosphor nanocomposite. The structural, morphological and optical features of the nanocomposite film have been studied and compared to those of a pristine PVP film and BAM:Eu powder. All the characterizations (XRD, SEM, SAXS, etc.) proved that the blue phosphor nanoparticles are well incorporated into the polymer nanocomposite film which exhibited the characteristic blue emission of Eu(2+) under UV light excitation. Furthermore, the photostability of the polymer/phosphor nanocomposite film has been studied after exposure to accelerated artificial photoageing at wavelengths above 300 nm.
4-Triazolyl-dipicolinic acids, prepared efficiently by CuAAC, proved to act as efficient antennae... more 4-Triazolyl-dipicolinic acids, prepared efficiently by CuAAC, proved to act as efficient antennae for optical lanthanide probes containing Eu(3+) or Tb(3+), under linear and non linear excitations (one, two and three photons provided by laser induced luminescence). The versatility offered by the substitution of the triazole subunit is, in addition, useful for covalent linkage to slide glass providing luminescent films.
... Luminescence Behavior of Sol−Gel-Derived Hybrid Materials Resulting from Covalent Grafting of... more ... Luminescence Behavior of Sol−Gel-Derived Hybrid Materials Resulting from Covalent Grafting of a Chromophore Unit to Different Organically Modified Alkoxysilanes. ... 1-2 The sol−gel technique has proven to be a convenient route for the preparation of such hybrid compounds. ...
... To achieve a resonant pumping in the blue wavelength range, that is, in the 5 D 2 manifold, t... more ... To achieve a resonant pumping in the blue wavelength range, that is, in the 5 D 2 manifold, the output of the dye laser was upshifted by 4155 cm - 1 by stimulated Raman scattering in a high-pressure gaseous H ... (1) Harmer, AL; Linz, A.; Gabbe, D.; Gillespie, L.; Janey, GM; Sharp ...
ABSTRACT Luminescent Tb3+ yttrium-based garnets powders have been prepared by the sol-gel route. ... more ABSTRACT Luminescent Tb3+ yttrium-based garnets powders have been prepared by the sol-gel route. Optical properties of samples have been studied. Excitation spectra have revealed several excitation bands between 200 and 500 nm, which match very well with newly developed AlGaN-based deep-ultraviolet (DUV) or near-UV LEDs. Excitation profiles are dependent on the matrix formula. Emission spectral features studied upon different UV excitation wavelength have revealed that luminescence efficiency can be significantly improved by tuning the matrix composition. Thus, optical properties can be tuned to optimize the lighting source features, according to the kind of UV LEDs employed.
Uploads