Xerogels luminescent

Ru(dpp)3]2+) sequestered within the xerogels. The results of SEM and luminescence measurements shown that certain ([Ru(dpp)3]2) doped Octyl-triEOS/TEOS composites form uniform, crack-free xerogel films that can be used to construct high-sensitivity O2 sensors that have linear calibration curves and excellent long-term stability (over a period of 11 months). 

The concept is extendable to templated sensors made of protein templated xerogels in which a luminescent reporter group is further added in close proximity to the template site so as to effectively transduce the protein-molecularly imprinted polymer binding event (Figure 6.12).11... 

Figure 2.19 ORTEP plot for Nd(L )3phen with ellipsoids drawn at the 30% probability level. Hydrogen atoms omitted for clarity [35]. (Reproduced from J. Feng, J.B. Yu, S.Y. Song, L.N. Sun, W.Q. Ean, XM. Guo, S. Dang and H.J. Zhang, Near-infrared luminescent xerogel materials covalently bonded with ternary lanthanide [Er(III), Nd(III), Yb(III), Sm(III)] complexes, Dalton Transactions, 13, 2406-2414, 2009, by permission of the Royal Society of Chemistry.)...

In this work we report on the method of fabrication the dichromatic luminescent images using intrinsic blue PL of PAA along with europium species deposited within the porous volume from a solution of an appropriate salt. The results are compared with generation of the structure xerogel/PAA. 

Time-resolved luminescence of europium complexes with organic ligands is investigated in several nonpolar organic solvents, xerogel, porous glass, and opal-polymer photonic crystals. Possible explanations of nonexponential luminescence decays of Eu ions in nanostmsctured dielectric environments are discussed. 

Figure 1. Luminescence kinetics (a-e) and corresponding decay time distributions (f-j) for Eu -(BTFA)3-BPhen in toluene (a, f)> polystyrene film(b, g), porous glass (c, h), xerogel(d, i), and opal-polymer photonic crystal (e, j).

ENHANCED LUMINESCENCE OF LANTHANIDES FROM XEROGELS IN POROUS ANODIC ALUMINA... 

Tb-implanted thermally grown silicon dioxide film, and (iii) Tb-doped alumina xerogels fabricated onto monocrystalline silicon. Thus, the terbium-doped alumina xerogel/PAA structure was proposed as a basis for green room-temperature luminescent images [17]. 

Figure 17.11. A. Photos of CdSe aerogels (large monolith) and xerogels (small monolith) under ambient (left) and UV (right) illumination B. Optical absorption data [black, converted from diffuse reflectance) and photo-luminescence [green) for CdSe/ZnS core/shell nanoparticles and corresponding aerogels and xerogels. Reproduced with permission from J. Am. Chem. Soc., 129 1840-1841 (2007). Copyright 2007 American Chemical Society.

The results showed that the decreased luminescence lifetime ofRu(bpy)3 in Si-Ti oxide xerogels can he mainly attributed to electron transfer from the excited state of Ru(bpy)3+ to the conduction hand of the titania. 

Modes S., Lianos P. Structural study of silicate glasses by luminescence probing The nature of small semiconductor particles formed in glasses. Chem. Phys. Lett. 1988 153 351-356 Momose F., Matsunaga K., Matsui K., Semura S., Kyoto M., Shida A. Photophysical and photochemical properties ofRu(bpy)j in Si-Ti mixed oxides xerogels prepared by the sol-gel process. J. Sol-Gel Sci. Tech. 2002 23 79-83... 

Besides research on thin films obtained by sol-gel, powders can also be obtained by this method and they are of particular interest in the production of phosphors. In a study of LuBOs phosphors (Boyer, 2002), the evolution of the Lu site as a function of thermal treatment was carried out by the EXAFS technique, from the xerogel to the conpletely crystallized samples. In this study, EXAFS revealed, in agreement with crystallographic results, that a vaterite structure is formed, instead of the calcite structure observed in the conventional solid-state reaction method. Also, Eu-doped Y2SiOs phosphors have been studied (Tao, 1996), relating the Eu-O bond length variation upon thermal treatment with the luminescence properties. 

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