Nanostructuration of YAG:Ce Coatings by ZnO Nanowires: A Smart Way to Enhance Light Extraction Efficiency.

In this study, we report on the enhancement of the light extraction efficiency of sol-gel-derived YAlO:Ce (YAG:Ce) coatings using ZnO nanowire (NW) arrays. The ZnO NWs were grown by hydrothermal synthesis from a ZnO seed layer directly deposited on a YAG:Ce coating. Highly dense and vertically aligned ZnO NW arrays were evidenced on the top of the YAG:Ce coating by electron microscopy.

Ce-doped YAG nanophosphor and red emitting CuInS2/ZnS core/shell quantum dots for warm white light-emitting diode with high color rendering index.

In this work, we report the solvothermal synthesis of Ce-doped YAG (YAG:Ce) nanoparticles (NPs) and their association with a free-Cd CuInS2/ZnS (CIS/ZnS) core/shell QDs for application into white light emitting diode (WLED). 1500 °C-annealed YAG:Ce NPs and CIS/ZnS core/shell QDs exhibited intense yellow and red emissions band with maxima at 545 and 667 nm, respectively. Both YAG:Ce nanophosphor and CIS/ZnS QDs showed high photoluminescence quantum yield (PL QY) of about 50% upon 460 nm excitation.

Investigation on combustion derived BaMgAl10O17:Eu2+ phosphor powder and its corresponding PVP/BaMgAl10O17:Eu2+ nanocomposite.

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.

Luminescent nanocomposites made of finely dispersed Y3Ga5O12:Tb powder in a polymer matrix: promising candidates for optical devices.

This paper reports the initial results of an original and simple method to elaborate flexible, self-standing, and thick luminescent films suitable for optical devices. PVP/Y(3)Ga(5)O(12):Tb(3+) nanocomposite films have been successfully achieved from a sol-gel derived Y(3)Ga(5)O(12):Tb(3+) powder and an alcoholic solution of poly-N-vinylpyrrolidone (PVP). The structural, morphological, and optical properties of these nanocomposite films have been studied and compared to those of a pristine PVP film and Y(3)Ga(5)O(12):Tb(3+) powder.

Modifications involved by acetylacetone in properties of sol-gel derived Y(3)Al(5)O(12):Tb(3+)- II: optical features.

Tb(3+)-doped Y(3)Al(5)O(12) powders have been synthesized from alkoxide precursors using, or not using, acetylacetone as a chemical modifier. The terbium oxidation state and local environment of amorphous and crystallized powders have been comparatively investigated by means of X-ray absorption near-edge structures (XANES) and extended X-ray absorption fine structure (EXAFS) while laser-induced luminescence was used to study their optical properties. Excitation and emission spectra have been recorded and a relative luminescence yield has been assessed upon 277 nm excitation.

Modifications induced by acetylacetone in properties of sol-gel derived Y(3)Al(5)O(12) : Tb(3+)- I: structural and morphological organizations.

Acetylacetone has been used as a chemical modifier for the synthesis of undoped and Tb(3+)-doped Y(3)Al(5)O(12) powders. A systematic investigation concerning its influence on the structural and morphological properties of amorphous and crystallized samples has been carried out. These properties have been comparatively studied by means of X-ray diffraction, infrared spectroscopy, SEM, XAS and SAXS.