67 results about "Luminescence quantum yield" patented technology

The present invention provides a core/multishell semiconductor nanocrystal comprising a core and multiple shells, which exhibits a type-I band offset and high photoluminescence quantum yield providing bright tunable emission covering the visible range from about 400 nm to NIR over 1600 nm.

A semiconductor nanocrystal composition that is stable and has high luminescent quantum yield. The semiconductor nanocrystal composition has a semiconductor nanocrystal core of a group II alloyed I-III-VI semiconductor nanocrystal material. A method of making a semiconductor nanocrystal composition is also provides which includes synthesizing a semiconductor nanocrystal core of a group II alloyed I-III-VI semiconductor material.

Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

A water-stable semiconductor nanocrystal complex that is stable and has high luminescent quantum yield. The water-stable semiconductor nanocrystal complex has a semiconductor nanocrystal core of a III-V semiconductor nanocrystal material and a water-stabilizing layer. A method of making a water-stable semiconductor nanocrystal complex is also provided.

The invention discloses a quantum-dot light-emitting diode and a preparation method thereof. The quantum-dot light-emitting diode comprises an inorganic electron transport layer, an electron buffer layer, a quantum dot light-emitting layer, a quantum dot modification layer and an inorganic hole transport layer. The electron buffer layer is disposed on the upper side of the inorganic electron transport layer; the quantum dot light-emitting layer is arranged at the upper side of the electron buffer layer; the quantum dot modification layer is arranged at the upper side of the quantum dot light-emitting layer; and the inorganic hole transport layer is arranged at the upper side of the modification layer. According to the invention, since the electron buffer layer is arranged between the inorganic electron transport layer and the quantum dot light-emitting layer and the quantum dot modification layer is arranged between eh inorganic hole transport layer and the quantum dot light-emitting layer, the damages on the quantum dot light-emitting layer by the inorganic electron transport layer and the inorganic hole transport layer can be reduced effectively, the luminous quantum yield of thequantum dot light-emitting layer is increased, and the carrier injection efficiency is modulated; the quantum dot light-emitting layer can be protected; the device is protected from being oxidized; the efficiency, service life and stability of the blue QLED are enhanced.

The invention relates to a temperature variable spectral measurement device, which comprises an excitation light source, an integrating sphere, a temperature control sample stage, a temperature controller and a detector. Specifically, the temperature controller is used for controlling the temperature of the temperature control sample stage, the excitation light source and the integrating sphere and the integrating sphere and the detector are all connected through optical fiber. The excitation light sent by the excitation light source is introduced into an integrating sphere entrance port of the integrating sphere through optical fiber and is incident to the temperature control sample stage, the light sent by a sample placed on the temperature control sample stage or the light reflected by the temperature control sample stage when no sample is placed thereon is collected by optical fiber through an integrating sphere exit port and is then introduced into the detector, by comparing the difference of emission spectra detected by the detector when a sample is placed and no sample is placed, the luminescence quantum yield can be calculated, thereby realizing measurement of sample luminescence. By combining the excitation light source and the detector, the temperature variable spectral measurement device provided by the invention can realize measurement of the temperature variable emission spectrum, quantum yield and other optical properties of a luminescent material.

The invention belongs to the field of organic light-emitting materials, and particularly discloses a carborane derivative. The structural formula is as follows: (img file='DDA0001282150470000011.TIF' wi='435' he='543' /), R1 and R2 is H or a derivative of phenanthrene, and R1 and R2 are not H together. The carborane derivative disclosed by the invention has the following advantages: through charge transfer emission and/or localized state emission, the emission wavelength of the compound can be accurately regulated, so that a series of white light molecules are obtained; by introducing the carborane group, luminescence quenching caused by the aggregation of solid state molecules is prevented, the absolute luminescence quantum yield is high, and the carborane derivative has good properties, such as good thermal stability and easy sublimation, and has actual application value.

The invention discloses a quantum dot surface purification method for improving the luminous efficiency of a perovskite LED. The method comprises the steps of: (1) adding a flocculant to a CsPbX3 quantum dot solution, carrying out centrifuging and then taking sediments; (2) dispersing the sediments into an organic solvent, adding a purification solvent, carrying out centrifuging again and taking the sediments; and (3) dispersing the sediments obtained in the step (2) into the organic solvent again and obtaining purified CsPbX3 quantum dots. Surface purification is carried out on the perovskite quantum dots by screening different solvents and cycle indexes; the number of ligands on the surfaces of the quantum dots is reduced; and the charge injection rate can be improved while the photoluminescence quantum yield is ensured, so that an QLED with high luminous efficiency is obtained; the photoluminescence quantum yield of the purified QLED is kept over 90%; and the external quantum efficiency is improved to 3.2% from 0.9%.

Two-dimensional (2D) transition-metal dichalcogenides have emerged as a promising material system for optoelectronic applications, but their primary figure-of-merit, the room-temperature photoluminescence quantum yield (QY) is extremely poor. The prototypical 2D material, MoS₂ is reported to have a maximum QY of 0.6% which indicates a considerable defect density. We report on an air-stable solution-based chemical treatment by an organic superacid which uniformly enhances the photoluminescence and minority carrier lifetime of MoS₂ monolayers by over two orders of magnitude. The treatment eliminates defect-mediated non-radiative recombination, thus resulting in a final QY of over 95% with a longest observed lifetime of 10.8±0.6 nanoseconds. Obtaining perfect optoelectronic monolayers opens the door for highly efficient light emitting diodes, lasers, and solar cells based on 2D materials.

It is an object of the present invention to provide a light emitting element and a light emitting device having high luminous efficiency. It is a further object of the present invention to provide a method for manufacturing the light emitting element using a simplified method compared with the conventional method. A light emitting element having a light emitting region which includes plural kinds of materials with a high luminous quantum yield, and one or plural kinds of materials with a high carrier transporting property and which has a structure where regions in which the material with a high luminous quantum efficiency is dispersed in a material with a high carrier transporting property and regions in which the concentration of the material with a high carrier transporting property is high are laminated alternately, between a pair of electrodes, is provided.

The invention discloses a rare earth complex luminescent material based on aromatic heterocyclic carboxylic class three-tooth anionic ligands and preparing method and application thereof. The general formula of rare earth complex is Ln (L)3. The L is 2-carboxyl-pyridines, 2-carboxyl-Furan, 2-carboxyl-thiophenes three-tooth anionic ligands replaced by phosphine oxygen radicals, sulfoxide group or sulphone. The Ln represents rare earth europium, terbium and dysprosium ions. The rare earth complex presents electric neutrality and is saturate in coordination structure, quenching, caused by solvent molecules, of rare earth luminescence is eliminated, and dissociation of the ligands is not likely to happen. The rare earth complex luminescent material is an effective and stable luminescent material. Particularly the luminescent quantum yield of the complex of europium and terbium reaches over 90%. The rare earth complex can be used as a conversion luminescence material excited by shortwave ultraviolet.

The invention relates to a low-temperature doped perovskite thin film with high photoluminescence quantum yield and a preparation method thereof. Low-temperature precursor liquid metal lanthanum ion doping is adopted, and the perovskite thin film with the high fluorescence quantum yield can be obtained without high-temperature injection and insulation ligand auxiliary crystallization. For perovskite with different band gaps, metal lanthanum ion doping can be carried out, and red, green and blue three-primary-color fluorescence emission can be basically obtained under 365 nm laser excitation. According to the method, in a relatively low-temperature environment, through temperature gradient annealing and solvent atmosphere annealing, the prepared perovskite crystal is higher in quality and fewer in defects, and a non-radiative composite path is effectively inhibited. The prepared perovskite thin film has a good application prospect in the field of semiconductor luminescence, and the efficient and simple preparation method of the perovskite thin film has great potential for commercial application of perovskite materials.

The present invention relates to conjugated polyelectrolyte (CPE) or oligoelectrolyte (COE) compounds represented by general structural formulae (I)-(IV), or a salt thereof and methods of using these compounds to detect targets in samples. In particular, the methods include: (1) exposing a sample to a compound of structural formula (I), (II) or (IV) or a salt thereof, allowing the compound to bind to a target and detecting a signal produced by the compound; (2) functionalizing a solid support with a ligand, incubating the sample with a charged CPE or COE and detecting the fluorescence of the solid support and thereby detecting the target or (3) functionalizing a surface of a solid support with a charged ligand, thereby creating a charge on the surface of the solid support; incubating the ligand-functionalized solid support with a sample, whereupon binding of the target, the charge on the surface of the solid support switches; incubating the sample with CPE or COE that has a complementary charge to the charge of the target-bound surface; and detecting the fluorescence of the solid support and thereby detecting the target. The compounds of the present invention possess high photoluminescence quantum yields in biological media, low cytotoxicity, and excellent environmental stability and photostability and can be used in biosensor and bioimaging applications.

The invention provides a water-soluble cyclized metal iridium complex with a sugary ligand and application of the complex, wherein the cyclized metal iridium complex is generated by means of reaction between the sugary ligand and a chlorendic dikaryon iridium complex, can serve as an electrochemical luminescence and photoluminescence probe and is applied to detecting amine drugs in an aqueous solution system or used for biological markers. The cyclized metal iridium complex serving as the luminous probe is water-soluble and high in luminous quantum yield, solves the problem of a metal iridium luminous probe is insoluble in aqueous solution, and can be applied to analysis and test in aqueous solution.

The invention relates to red light emission fluorescent powder which can be produced under excitation of ultraviolet/blue light. A chemical expression formula of the material is xMn<4+>: CaMg<2>Al<16>O<27> (x is more than or equal to 0.016 and less than or equal to 0.48). The invention also provides a preparation method of the red fluorescent powder. The red fluorescent powder is high in stability, and can be effectively excited by 250-500 nanometers of ultraviolet/blue light so as to produce 620-700 nanometers of red light emission so that the fluorescence quantum efficiency reaches 47.2 percent. The fluorescent powder can be used for building warm white LED excited by an ultraviolet/blue light chip.

The invention discloses a quantum dot light-emitting device, a preparation method thereof, a display panel and a display device and aims to reduce fluorescence resonance energy transfer and improve photoluminescence quantum yield. According to the embodiments of the invention, the quantum dot light-emitting device comprises a quantum dot light-emitting layer, wherein the quantum dot light-emittinglayer comprises light-emitting quantum dots and a semiconductor spacer material mixed with the light-emitting quantum dots; the energy level of the semiconductor spacer material spans the forbidden band of the light emitting quantum dots.

The invention relates to a U-shaped dicaryon metal platinum complex with polymorphic light emission and a preparation method of the U-shaped dicaryon metal platinum complex. The U-shaped dicaryon metal platinum complex is a dicaryon metal platinum complex of an alkyl-substituted urea bridged U-shaped molecular structure, in the formula, R is any one of C1-C12 aliphatic groups, and R1 is any one of alcoxyl alkyl, hydrogen atoms, fluorine atoms, trifluoromethyl and C1-C12 aliphatic groups. The U-shaped dicaryon metal platinum complex with polymorphic light emission, which is provided by the invention, has a solvent-adjustable polymorphic light emission property, materials of three different crystal states can be prepared according to different solvents for crystallization, the metal platinum complex has relatively good dark red phosphorescence in solvents such as methanol or chlorobenzene, and a dark red light-emitting crystal state material prepared from the metal platinum complex has relatively high lower-state light-emitting quantum yield, and can be applied to fields of light-emitting and display devices.

The invention provides a preparation method of Mn<4+>-activated fluoride fluorescent powder. The preparation method provided by the invention does not need to form a saturated solution of A2MF6, so that the requirement of the use amount of raw materials is greatly reduced; in the preparation process, the target product can be synthesized at room temperature and is convenient to synthesize; a precipitating agent is added, so that the preparation is more convenient, the operation is simpler, the synthetic steps are simplified, and the prepared fluorescent powder has better optical properties; the fluoride fluorescent powder can be well excited by ultraviolet light to blue light, especially the blue light, and has strong red light emission, wherein the red light emission peak is in the wavelength range from 600 to 650 nm; the method has the advantages of a simple preparation process and short consumed time; and the prepared material has a high luminescence quantum yield and is suitable for industrial large-scale preparation.

The invention discloses a preparation method of a water-borne polyacrylate for emitting room temperature phosphorescence. The preparation method is characterized by comprising the following steps: firstly an acrylate monomer capable of emitting the room-temperature phosphorescence is prepared; then emulsion copolymenzation on the acrylate monomer and one or a plurality of common acrylate monomers is carried out, so that a phosphorescence chromophore is embedded into molecular chains of the water-borne polyacrylate in a form of chemical bonds and the prepared water-borne polyacrylate has the function of emitting the phosphorescence at room temperature. The water-borne polyacrylate capable of emitting the room temperature phosphorescence prepared by using the method disclosed by the invention is an organometallic complex-free pure organic photoluminescence polymer phosphorescent material, is simple in a synthetic process, low in cost, non-toxic, pollution-free and wide in application range; the content of the phosphorescence chromophore can be controlled at 1-10 wt%, and the chromophore is embedded into the molecular chains of the water-borne polyacrylate in the form of the chemical bonds, and is low in migration rate and longlasting in light emission, and the yield of light-emitting quanta reaches 70%.

A nanocrystal preparation method comprises the following steps: dissolving, in a first selected solvent, a first precursor which is in a gaseous state under normal temperature and normal pressure, to form a first precursor solution; dissolving a second precursor in a second selected solvent to form a second precursor solution, wherein the second precursor is a precursor of a metal element of Group I, Group II, Group III or Group IV; and in an inert gas atmosphere, adding the first precursor solution into a reaction vessel which contains the second precursor solution, wherein the first precursor chemically reacts with the second precursor to generate a nanocrystal. The present invention further discloses a nanocrystal prepared by the above method and an apparatus for preparing and storing a gas-dissolved solution. With the preparation method according to the invention, the amount of the first precursor in a gaseous state can be accurately controlled, the reaction is more uniform and more controllable, and the obtained nanocrystal has uniform volume distribution and a higher luminescent quantum yield.

The invention provides a thermally activated delayed fluorescent molecular material and a synthesis method thereof, and an organic electroluminescent device. The thermally activated delayed fluorescent molecular material comprises an electron donor and an electron acceptor, wherein the electron acceptor contains an indenyl. By substituting the phenyl in diphenylamine or triphenylamine in a donor molecule with indenyl, the electron donating ability of the donor can be increased, and the non-radiative transition rate can be effectively suppressed, thereby increasing the molecular photoluminescence quantum yield (PLQY), also increasing the torsion angle between the electron donor and the electron acceptor, at the same time reducing the electron cloud overlapping between a highest occupied molecular orbital (HOMO) and a lowest unoccupied molecular orbital (LUMO), and accordingly acquiring small delta EST.

The invention discloses a perovskite quantum dot glass film and a preparation method and an application thereof. The PDMS and CsPbX3 quantum dot glass powder are added for simple physical mixing and dilution, the internal filtering effect is eliminated, and the photoluminescence quantum yield of the CsPbX3 quantum dot glass composite material can be greatly improved; and the highest photoluminescence quantum yield obtained by the CsPbBr3 quantum dot glass is 97%. The CsPbX3 quantum dot glass has excellent light stability and water resistance/heat resistance due to effective isolation between the quantum dots and the external environment due to coating of the glass network unit, and the luminous intensity of the CsPbX3 quantum dot-inorganic glass-silica gel composite film is almost unchanged when the CsPbX3 quantum dot-inorganic glass-silica gel composite film is irradiated under a 6W ultraviolet lamp for 7 days and soaked in boiling water at 90 DEG C for 24 hours. A high-performance backlight liquid crystal display is designed by adopting the CsPbX3 quantum dot-inorganic glass-silica gel composite film, the color gamut area of the high-performance backlight liquid crystal display reaches 152% of that of commercial liquid crystal display and 103% of that of the 1953 standard of the national television standard committee (America), and the high-performance backlight liquid crystal display has huge potential in the optoelectronic industry.

The invention provides a thermally activated delayed fluorescence molecular material, a synthesis method thereof, and an electroluminescent device. Through synthesizing a thermally activated delayed fluorescence molecule containing a indolobenzo selenium-heteroaromatic aromatic ring donor, the electron donating ability of the donor is enhanced, and the rate of nonradiative jump can be effectivelyinhibited, thus increasing the luminescence quantum yield (PLQY) of the molecule, and increasing the torsion angle between the electron donor and an electron acceptor while reducing electron cloud overlap between the highest occupied molecular orbit (HOMO) and the lowest occupied molecular orbit (LUMO), resulting in a smaller [delta]EST. The electroluminescent device adopts the thermally activateddelayed fluorescence molecular material, and has a high luminous efficiency and long service lifetime.