Luminescence quenching by oxygen

Luminescence Quenching by Oxygen in Polymer Films Xin Lu and Mitchell A. Winnik... 

Luminescence quenching by oxygen appears to be a similar process with Q = Oj. The process is diffusion-controlled, and it may be thought of as... 

Trivalent lanthanide cations have luminescent properties which are used in a number of applications. The luminescence of the lanthanide ions is unique in that it is long-lasting (up to more than a millisecond) and consists of very sharp bands. Lanthanide emission, in contrast to other long-lived emission processes, is not particularly sensitive to quenching by oxygen because the 4f electrons found within the inner electron core... 

In the silica nanomatrix, the low diffusion was also reported in both liquid and gas phases. In the gas-phase reaction, it was found that the luminescence signal of Ru(bpy)32+ doped in DDSNs remained stable when the air pressure increased from 1 to 8 psi, showing no quenching by oxygen in the air. When the air pressure was further increased to above 8 psi, a decrease in fluorescence emission intensity was observed. The results suggested a slow diffusion of quencher oxygen in the silica nanomatrix. 

Long-lived photoluminescence, at 826 nm, is reported (t 15 (is) for thin films of the processable, -conjugated polymer, poly(3-hexylthio-phene) (93JA8447). Excitation of the n—n transition with 518 nm light (So >S ) yields only very weak luminescence of 826-nm light, even at 18 K. The emission is enhanced, to point where it can be observed at room temperature, when the excitation wavelength is 250 nm, but it is completely quenched by oxygen. Prompt fluorescence decays within... 

Abstract Pressure-sensitive paint (PSP) is applied to the areodynamics measurement. PSP is optical sensor based on the luminescence of dye probe molecules quenching by oxygen gas. Many PSPs are composed of probe dye molecules, such as polycyclic aromatic hydrocarbons (pyrene, pyrene derivative etc.), transition metal complexes (ruthenium(II), osumium(II), iridium(III) etc.), and metalloporphyrins (platinum (II), palladium(II), etc.) immobilized in oxygen permeable polymer (silicone, polystyrene, fluorinated polymer, cellulose derivative, etc.) film. Dye probe molecules adsorbed layer based PSPs such as pyrene derivative and porphyrins directly adsorbed onto anodic oxidised aluminium plat substrate also developed. In this section the properties of various oxygen permeable polymer for matrix and various dye probes for PSP are described. 

At least two upper electronic states have to be assumed when interpreting the luminescence results. Evidently, the electronic state eliminated by the temperature increase is the same as that quenched by oxygen or nitric oxide. 

The light emitted by biacetyl consists of a green and a blue luminescence the former is the phosphorescence, while the latter is the fluorescence. The life-time of the triplet state, responsible for the phosphorescence, is 1.4x 10 -1.8x 10 sec °° ° 243.314 Phosphorescence is quenched by oxygen and iodine ... 

The luminescence of terbium (42) and europium macrocyclic complexes have been studied and found to depend upon pH. The phenanthridine sidechain acts as a photosensitizer and (42) exhibits luminescence quenched by molecular oxygen corresponding Eu compounds exhibit halide-quenched emisssion. ... 

Other OTM compounds that are indicated by preliminary studies to be efficient triplet sensitizers include ClRe(C0)2L (Table 12). In dichloromethane at room temperature these complexes are strongly luminescent and photo-inert (41). Under the same conditions, the emissions are quenched by oxygen, anthracene, and trans-stilbene. The trans cis isomerization of trans-stilbene is efficiently sensitized by several of these species. Quantitative sensitization experiments indicated that the luminescing excited states of ClRe(C0)3L are produced with 100 percent... 

It is considered that PSMF composed of palladium-porphyrin complex works in low-pressure range (below 130 Pa), because the luminescent lifetime of palladium-porphyrin complex is long (ca. 1 msec) and the luminescence with short lifetime is rarely quenched by oxygen molecule during its lifetime under low-pressure condition. Pd (11) octaethylporphine (PdOFP) is a well-known luminescent dye adopted in PSP for low-pressure condition. Matsuda et al. [11] fabricated PSMF composed of PdOFP. However, since PdOFP is a hydrophobic molecule, the LB film containing PdOFP was very unstable and was difficult to be deposited on to a substrate. 

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