138 results about "Concentration quenching" patented technology

The present invention provides a secured document including a composition capable of anti-Stokes fluorescence containing an ion capable of absorption of electromagnetic radiation, an ion capable of emitting electromagnetic radiation, and a matrix composition comprising gadolinium, yttrium, lanthanum, and luetium, wherein the wavelength of the emitted electromagnetic radiation is shorter than the wavelength of the absorbed electromagnetic radiation, and wherein the concentrations of the absorbing and emitting ions are adjusted to achieve concentration quenching of anti-Stokes luminescence.

The invention provides a pyridine-fluorene organic electrophosphorescence main body luminescent material and a preparation method thereof, relating to new-generation organic luminescent display materials and technology. Due to the rigid structure, the luminescent material has high triplet energy level and favorable hole injection and transmission performance; and due to the three-dimensional large-volume steric hindrance effect, the luminescent material has stable amorphous state, and thus, can be widely used in organic light-emitting diodes. The specific design structure of the pyridine-fluorene main body material is disclosed in the specification. The invention particularly relates to a preparation method and application in organic light-emitting diode devices. The material has the advantages of high luminescence efficiency, high heat stability, high glass transition temperature and simple synthesis method, and can effectively inhibit concentration quenching and dimer luminescence. The preliminary structure as the main body material implements red-green-blue tricolor organic electroluminescent devices. The compounds have wide application prospects and huge commercial value in the aspects of electrophosphorescent main body materials.

A high-gain phosphate glass composition, which can be used to produce ultra-short gain length lasers and optical amplifiers is described wherein the composition of the glass in addition to exhibiting high gain for lasers and amplifiers, also exhibits high thermal shock resistance, high cross section, insignificant concentration quenching, and high solubility for rare earth ions and other properties which enable the material to be fabricated into a new class of ultra-short length micro-laser, fiber laser and amplifier configurations and designs.

A light-emitting device includes a light-emitting diode, a red light-emitting phosphor layer, a yellow light-emitting phosphor layer, and a blue light-emitting phosphor layer. These layers are stacked in the stacking sequence of the yellow, blue, and red phosphor layers in order of increasing distance from the LED. The stacking sequence of the yellow and blue phosphor layers is first determined in such a manner that these layers do not interact with each other. The stacking sequence of the red and yellow phosphor layers and the stacking sequence of the red and blue phosphor layers are determined by the discriminant D. This determination of the stacking sequence suppresses a reduction in the conversion efficiency of the phosphors due to concentration quenching, improving the emission efficiency of the light-emitting device.

The invention provides a single-particle nano crystal with three-primary-color luminescence and a preparation method thereof. The single-particle nano crystal has a core-shell structure and sequentially comprises an inner core, a first shell, a second shell, a third shell and a fourth shell from inside to outside, wherein the inner core, the second shell and the fourth shell are luminous shells, and the first shell and the third shell are inert shells. The three luminous shells separately contain Yb<3+>/Tm<3+>, Er<3+> or Nd<3+>/Yb<3+>/Er<3+> ions, and the luminescent shells respectively radiate red, green and blue lights under the action of a laser. According to the invention, shell stock solutions with different components are continuously and thermally injected by adopting a one-pot method, and compared with a conventional batch thermal injection method, the one-pot method has the advantages that the time required for synthesizing nano particles with a multilayer core-shell structureis greatly saved. Through constructing a ''core-multi-shell'' structure, concentration quenching and luminescence color crosstalk are inhibited, and high-efficiency pure-color three-primary-color luminescence is realized. The nano crystal has a real-time color adjustment capability in full color gamut, and the adjustment method is simple and convenient.

Disclosed is a method for enhancing upconversion luminescence of rare-earth doped particles comprising a host material, an enriched concentration of activator (emitter) and a sufficient concentration level of sensitiser, the method comprising subjecting the particles to increased irradiance. The increased irradiance is higher than presently used relatively low irradiance levels. Enhancing upconversion luminescence involves enhancing luminescence intensity, brightness and/or upconversion efficiency. Particles are preferably subjected to an irradiance power density sufficient to overcome or reverse concentration quenching. The activator preferably has an intermediate meta stable energy level which accepts resonance energy from the sensitiser excited state level. In another form, particles are designed to minimize or exclude quenchers from the upconversion system between sensitizer and activator, such as the core-shell particles wherein the core comprises the host material, sensitiser and the activator, and the shell comprises a material which prevents, retards or inhibits surface quenching.

The invention discloses a thermo-activating delayed fluorescent material allowing solution processing and a preparation method thereof, wherein the molecular structure of the material is composed of two parts: one is a core having property of thermo-activating delayed fluorescence, the other is a group connected via an alkyl chain and having high triplet state energy level. The molecular structureis represented as the formula (I), wherein at most one of R1 and R2 is hydrogen, others being the group connected via an alkyl chain and having high triplet state energy level. The novel material hasthe following advantages: due to the steric-hinerance effect of surrounding branch chains, concentration quenching of a triplet-state exciton is effectively reduced, thus improving performance of a light-emitting device. By introducing the alkyl chain, dissolubility and film-forming performance of the material are effectively enhanced. A result proves that the thermo-activating delayed fluorescent material has large molecular weight and excellent film-forming performance, so that the material is suitable for preparing an organic light-emitting device in a wet process. With increase of the surrounding branch chains, the performance of the device can be improved greatly.

The invention relates to a blue light naphthalimide fluorescent compound with high solid fluorescence efficiency, which has the structure general formula shown at right, wherein R1 radical is 2-hydroxyethyl or 2-acetoxyl ethyl, R2 is hydrogen atom or tert-butyl group, and R3 is hydrogen atom or tert-butyl group. By introducing the tert-butyl group with large steric hindrance into the benzene ringof the 4-position phenoxyl substitutional group of 1, 8- naphthalimide, the invention increases the volume of target fluorescent molecules and reduces the mutual actions among the fluorescent molecules so as to reduce the concentration quenching action and enhance the solid fluorescence quantum efficiency. By introducing the tert-butyl group with large steric hindrance into the 2-position of the benzene ring of the 4-position phenoxyl substitutional group, the invention reduces the coplanarity of the benzene ring, oxygen atoms and a naphthalimide ring so as to ensure that the solid fluorescenttransmitted wavelength of the target fluorescent molecules shifts from aquamarine blue to ethereal blue.

The invention discloses a double-nuclear ring metal platinum complex near-infrared light-emitting material and an application thereof. The double-nuclear ring metal platinum complex near-infrared light-emitting material comprises a ring metal ligand forming a double-nuclear ring metal platinum complex, i.e. the first ligand which is 1-phenylisoquinoline, and an auxiliary ligand forming the double-nuclear ring metal platinum complex, i.e. the second ligand which is 5-aryl-2-sulfydryl-1,3,4-oxadiazole anion ligand. The invention improves the transmission and capture function of current carriers of the double-nuclear ring metal platinum complex and the dispersing performance of the current carriers in a polymer main material, effectively inhabits the phase separation and the concentration quenching of the ring metal platinum complex in the polymer material and improves the light-emitting efficiency of a near-infrared polymer electrophosphorescent element by the 5-aryl-2-sulfydryl-1,3,4-oxadiazole anion ligand.

The invention provides a preparation method of rare earth doped nano zirconia up-conversion phosphor powder. The preparation method comprises respectively dissolving Zr(NO3)4 and Zr(NO3)3 into deionized water according to 0.05-0.2:1 of the molar ratio of the Zr(NO3)3 to Zr(NO3)4, stirring to enable the solution to be clear to obtain mixed solution, adding citric acid with the ratio of the citric acid to cation in the mixed solution being 4:1, then adding ammonia water, regulating the pH value of the solution to be 6.5-7.5 and stirring to form collosol; drying the collosol at the temperature of 130 DEG C to form gel, sintering the gel at the temperature of 800 DEG C to obtain white precursor phosphor powder, and finally calcining the precursor phosphor powder at the temperature of 1100 DEG C-1400 DEG C to obtain the rare earth doped nano zirconia up-conversion phosphor powder. The preparation method is a scheme which can effectively weaken concentration quenching effect of high-doping rare earth ions and has the advantages of being simple in synthetic process, low in cost and the like. In addition, the luminescent efficiency of finished products is high.

The invention relates to a preparation method of an ultraviolet fluorescent-green plastic film by taking rare-earth phosphate glass as a photochromic agent and application thereof in anti-counterfeiting aspects. Aiming at the problems of doped rare-earth fluorescent polymer materials, such as large polarity difference between an inorganic rare-earth fluorescent agent and a polymer material, rare-earth fluorescent concentration quenching, fluorescence stability and the like, the ultraviolet fluorescent-green plastic film has the characteristics that the phosphate glass is used as the substrate, Tb<3+> ion is used as a fluorescent activator, and Ce<3+> ion is used as a sensitizing agent, so that the fluorescent concentration quenching phenomenon is overcome, and the Eu addition amount and the fluorescence efficiency are increased through the synergistic effect of the phosphate glass matrix, Tb<3+> and Ce<3+> in the formula; glass fragments are pressed by using a melting method and an ice water mixture cooled glass tablet press, and then, the phosphate glass:Tb<3+>, Ce<3+> fluorescent powder with the granularity of being less than 300 nm is prepared through high-pressure grinding of an air-current mill; a surface modifier is added, fluorescent powder and polymer master-batch are molten and blended, and the plastic film obtained by being blown is white and transparent in the sun and emits beautiful green light under irradiation of ultraviolet light; and the plastic film has special transmission spectrum and can be used as an anti-counterfeiting packaging film, an anti-counterfeiting label printing substrate and an anti-counterfeiting safety line substrate.

The invention discloses a method for determining aflatoxin. The method is characterized by comprising the following steps: (1) preparing a solution 1 for later use; (2) preparing a solution 2 for later use; (3) preparing R1 modified by HRP (horseradish peroxidase); (4) preparing R2 modified by HRP; and (5) detecting aflatoxin. Red rhodamine B can neither cause concentration quenching, nor cause insufficient light intensity. By adding mica powder, the luminescence lifetime of an oxalate luminescence system is significantly prolonged. Ruthenium terpyridine and chemiluminescence have the advantages of high detection sensitivity, wide linear range and the like, and aflatoxin can be detected more effectively. The method disclosed by the invention has the excellent properties of lower toxicity, higher flash point and lower vapor pressure. By detecting the content of aflatoxin in liquid milk and using a standard addition recovery method, the recovery yield of 98.4%-100.4% is obtained, indicating that the method has good accuracy in determination of aflatoxin.

The invention relates to a dibenzothiophene-based aromatic phosphine oxide compound and a preparation method and application thereof. The invention solves the problems that an electrophosphorescent device has low efficiency and low brightness because the conventional electrophosphorescent material has serious concentration quenching and triplet-triplet annihilation effects. The structural general formula of the compound is that: X is H or a diphenylphosphine oxide group. The compound is obtained by the steps of: preparing a derivative from dibenzothiophene, n-butyllithium, tetramethylethylenediamine and diphenylchlorophosphine, dissolving the derivative into CH2Cl2, adding H2O2 and reacting. The invention also relates to application of the compound to organic electroluminescent light-emitting diode devices and application of the compound used as a main material of a luminescent layer. An electroluminescent blue-light and green-light main material with high triplet excited-state energy level and good carrier injection and transmission capacity is obtained by modifying the diphenylphosphine oxide group onto a chromophore parent through a C-P saturated bond; and the prepared device has high turn-on voltage, brightness and efficiency stability.

As a green light emitting phosphor capable of emission upon excitation with light having a wavelength of 350 to 500 nm, characterized in containing Tb³⁺ ions as emission ions in high concentrations without causing concentration quenching, the present invention provides a green light emitting phosphor capable of emission upon excitation with light having a wavelength of 350 to 500 nm, characterized by having a composition represented by the compositional formula (1):

ATb_xLn_(1-x)M₂O₈  (1)

wherein A is at least one element selected from the group consisting of Li, Na, K, and Ag, Ln is at least one element selected from rare earth elements including Y and excluding Tb, M is at least one element selected from the group consisting of Mo and W, and x is a positive number satisfying 0.4≦x≦1, and a light emitting device incorporated with the green light emitting phosphor.

The invention discloses a dibenzofuranyl aromatic phosporic-oxygenic compound and a preparation method and application thereof, relating to the dibenzofuranyl aromatic phosporic-oxygenic compound and the preparation method and the application thereof. The problems of low luminous efficiency and brightness and poor stability of an electrophosphorescent device, caused by serious concentration quenching and a triplet annihilation effect existing in the traditional electrophosphorescent material, are solved. In a general structural formula of the compound, X represents H or diphenyl phosporic-oxygenic group. The preparation method comprises the following steps of: preparing a derivative by using dibenzofuran, butyl lithium, tetramethylethylenediamine and diphenylphosphine chloride; dissolving the derivative in CH2CI2; adding H2O2; reacting; and thus obtaining the compound. In the application of an organic electrophosphorescent device, the compound is used as a main material of a luminescent layer. The diphenyl phosporic-oxygenic group is modified on a chromophore patent body through a C-P saturated bond to prepare electro blue/electro white/electro green main materials which are high in triplet excited state energy level and have good carrier injection and transmission capacity, and the prepared device has extremely low driving voltage, excellent brightness and stable efficiency.

The invention relates to a photoelectric functional aromatic phosphine oxide compound, and a preparation method and application thereof, which are used for solving the problems of being high in driving voltage of a device, low in efficiency and brightness and poor in efficiency stability caused by serious concentration quenching and triplet-triplet annihilating effects existing in the traditional electrophosphorescent material. A general structural formula of the compound is shown as an equation in the specification, wherein X represents two hydrogen, and Y represents one hydrogen; or X represents two hydrogen, and Y represents diphenyl phosphine oxide; or X represents isopropyl, and Y represents diphenyl phosphine oxide. The compound is obtained by respectively carrying out lithiation, phosphorization and oxidation reactions on 2-position or 2,2'-position of phenylate or 4-position and 5-position of 9,9-dimethyl-xanthene under the action of tetramethylethylenediamine. The compound is applied to a light emitting layer main material in an organic electrophosphorescent device. The compound forms multiple conjugated interrupted systems through P=0 and -O-. A prepared device has ultra-low driving voltage and excellent brightness and efficiency stability and is used as an electrogenerated blue light/green light main material.