57results about How to "Reduce non-radiative transitions" patented technology

The invention provides a cadmium-free core-shell quantum dot and a preparation method thereof; the cadmium-free core-shell quantum dot comprises a quantum dot core, a gradual transition layer continuously grown on the surface of the quantum dot core, and a shell layer formed on the surface of the gradual transition layer, wherein the gradual transition layer comprises core cations and core anions in the quantum dot core, and shell cations and shell anions in the shell layer; in the cadmium-free core-shell quantum dot, the concentrations of the core cations and core anions decrease gradually from inside to outside, and the concentrations of the shell cations and shell anions gradually increase from inside to outside.

The invention discloses star-shaped tetraaryl ethylene compounds. In the invention, the star-shaped tetraaryl ethylene compounds with rigid frameworks are synthesized through molecular design, each compound molecule contains one or more tetraaryl ethylene groups, and the compounds have special luminescent properties, namely the properties that the compounds almost have no fluorescence in dilute solution and fluorescence is greatly enhanced in an aggregation state or solid state. The invention also discloses a preparation method for the star-shaped tetraaryl ethylene compounds. The compounds have higher decomposition temperature and high thermal stability, and can be used as organic fluorescent materials which are applied to devices. The structural general formula of the compounds is shownin the specification, wherein X and Y are positive integers and the sum of X and Y is equal to 6.

The invention discloses a method for preparing a red strontium sulphide long afterglow material, comprising a hydrothermal coprecipitation method which comprises the following steps that: (a) water-solubility strontium salt, water-solubility europium salt, water-solubility dysprosium salt, carbamide and water are weight according to the mol ratio of 1: between 0.01 and 0.05: between 0.01 and 0.05: between 4 and 6: between 28 and 32 and are put inside a container to be stirred and dissolved, the mixture is insulated in a sealing state at a temperature of between 80 and 160 DEG C for 5 to 24 hours so that a precursor is obtained; (b) the precursor is subject to filtering and annealing at a temperature of between 900 and 1200 DEG C in the reaction environment for 0. 5 to 2 hours so that the red strontium sulphide long afterglow material is prepared; the water-solubility strontium salt is strontium nitrate or strontium chloride or strontium acetate, the water-solubility europium salt is europium nitrate, europium chloride or polyimide, the water-solubility dysprosium salt is dysprosium nitrate or dysprosium chloride or dysprosium acetate, and a surface active agent is added according to the mol ratio of the water-solubility strontium salt to the surface active agent of 1: between 0.0001 and 0.0003. The method is widely applied to the fields such as building decoration, traffic transportation, military facilities, fire emergency service and goods for everyday consumption.

The invention provides a detection reagent and a quantitative detection method of human serum albumin and belongs to the technical field of fine chemical engineering. Based on a combining attribute of albumin and small molecules, the specific principle of the method is that HCAB can be specifically combined with the albumin, a charge transferring phenomenon in HCAB twisting molecules is inhibited and non-radiation transition is reduced, so that fluorescent light is recovered and quantitative detection of the albumin is realized. After the human serum albumin is excited under a physiological pH value condition (an excitation wavelength lambdaex is equal to 424nm), a stable fluorescent signal (an emission wavelength lambdaem is equal to 526nm) is generated. The fluorescent value intensity is in direct proportion to the concentration of the albumin; and according to a detected fluorescent value, the content of the albumin in a biological sample can be calculated. The method can be used for determining absolute content of the albumin in a plurality of types of biological samples including blood serum, urine and the like; and meanwhile, the method also has the advantages of high sensitivity, high accuracy, high environment interference resisting capability, easiness of carrying out high-flux detection and the like.

The invention provides a method for preparing a CdZnSe/CdSe/ZnSe green light quantum point. Specifically, a precursor high-temperature injection method and a growth method are combined, the ratio of Zn to Cd in CdZnSe is adjusted, then core quantum dots of different and uniform sizes can be prepared, later cores are coated with a thin CdSe shell layer, then a light emission wavelength is approximate to 550nm, in addition, by controlling reaction velocities and temperatures, quantum point size uniformity can be ensured, finally ZnS is adopted as the shell layer for surface modification, light emission wavelengths are regulated and controlled, and the wavelength of the CdZnSe/CdSe/ZnSe quantum point is about 540nm. The CdZnSe/CdSe/ZnSe green light quantum point prepared by using the method has a fluorescence quantum yield of 90%, has a full width at half maximum of 30nm, has a great application prospect in efficient quantum point light emitting diodes, and is capable of remarkably improving photoelectric properties of light emitting diodes.

The invention discloses a fluorescence illuminating fluorescent material for detecting explosive, a preparing method and application, and belongs to the field of fluorescence sensors. A structural formula of the fluorescent material is as shown in formula I and formula II. When the structural formula is I, the fluorescent material is prepared by Suzuki coupling reaction of TPP and phenylboronic acid with different substituent groups at para-positions; a polymer is prepared by hydrosilylation of V-TPP and polymethylsiloxane; the fluorescent material is used for quantitative detection of the explosive and specific detecting steps comprise: dissolving the fluorescent material in a mixed solvent of tetrahydrofuran and water to obtain a fluorescent reagent; measuring the initial fluorescence intensity of the fluorescent reagent, then placing an explosive solution to be detected into the fluorescent reagent in sequence, uniformly stirring after adding every time, and instantly measuring the fluorescence intensity, wherein by comparing the change of the fluorescence intensity before and after the explosive solution is added, along with increment of the explosive, the fluorescence intensity of the fluorescent reagent is enhanced.

The invention belongs to the technical field of luminescence and display, and particularly relates to a D-pi-A type AIE-TADF near-infrared luminescent material and a preparation method and application thereof. According to the near-infrared luminescent material, phenyl dicyanoquinoxaline with strong electron absorption is used as an acceptor (A) unit, and triarylamine[diphenylthiophenamine, di(4-methoxyphenyl)thiophenamine and di(4-fluorophenyl)thiophenamine] with strong electron donating is used as a donor (D) unit. The near-infrared luminescent material is high in thermal stability and has excellent carrier transport performance and photoluminescence performance, and the fluorescence quantum efficiency of the near-infrared luminescent material is 27%, so that the near-infrared luminescent material is widely applied to the fields of organic electroluminescent displays, biological imaging and the like.

The invention relates to a preparation method for a multi-shell CdZnS/CdSe/ZnS core/shell-structured quantum dot. A high-temperature hot injection method, an alternating successive ionic layer adsorption growth method and a double-precursor method are adopted to synthesize the CdZnS/CdSe/ZnS quantum dot, wherein the quantum dot can be synthesized by another four types of feasible solutions. By continuously wrapping CdSe and ZnS shell layers with different thicknesses and different layer numbers, the preparation method can obtain a continuously tunable wide spectral range, and the multi-shell CdZnS/CdSe/ZnS core/shell-structured quantum dot has the characteristics of good monochromaticity, good monodispersity, narrow and symmetrical fluorescence emission peaks and the like, can also increase the stability of light emission, and has more and better optical properties than an individual CdZnS quantum dot and an individual CdSe quantum dot or a CdZnS/CdSe quantum dot. Moreover, by changingthe thickness of the CdSe shell layers and continuously wrapping the ZnS shell layers, the distribution state of electron holes of the quantum dot can be changed, consequently, a variety of materialswith different properties can be prepared, and the quantum dot can be further applied in various aspects.

The invention provides a compound and application thereof, and an organic electroluminescent device comprising the same, the compound has a structure of formula (I), and the compound is used as a material of a luminescent layer in the organic electroluminescent device; and the organic electroluminescent device comprises a first electrode, a second electrode and an organic layer between the first electrode and the second electrode, and the organic layer contains any one or a combination of at least two of the compounds. The compound provided by the invention can further reduce the efficiency roll-off of the device and prolong the service life of the device on the premise of ensuring proper driving voltage.

The invention discloses a polarity-sensitive fluorescence probe and a preparation method and application thereof. A structural formula of the probe is as shown in the specification, wherein R1 is H, CH3, CH3CH2 or COOH; and R2 is CH3, CH3CH2 or CH3CH2CH2. The preparation method comprises the following steps: reacting a reactant 1 and a reactant 2 at a low temperature in an anhydrous anoxic reactor; and adding a reactant 3, reacting at a room temperature, and carrying out treatment such as skimming and purification, so as to obtain the probe. The probe has the specific fluorescence response on the solvent polarity, and is fast in response; the fluorescence wavelength is relatively large during response; the preparation method is simple; and the response detection on the solvent polarity is convenient.

The invention relates to an aryl boron derivative based thermally activated delayed fluorescent material and an organic light-emitting device. The thermally activated delayed fluorescent material hasa structure shown as formula A. The invention also relates to an organic light-emitting device, which consists of a luminescent layer, and the luminescent dye in the luminescent layer is the thermallyactivated delayed fluorescent material. The thermally activated delayed fluorescent material has very small single state-triplet state energy gap, and at room temperature, triplet state exciton can be upconverted to triplet state excitonic luminescence by thermal activation. The thermally activated delayed fluorescent material has the advantages of simple synthesis, high luminous efficiency, small concentration quenching effect and good solubility. And the organic light-emitting device based on the material can acquire high efficiency and good device stability.

The invention belongs to the technical field of composite materials, and more particularly relates to a photo-responsive composite material, a preparation method and application thereof. The compositematerial comprises a polymer substrate and carbonized polymer quantum dots dispersed in the polymer substrate, and a photoacid generator or a photobase generator, wherein the carbonized polymer quantum dots are capable of emitting fluorescence; and an acid generated by the photoacid generator or an organic base generated by the photobase generator is capable of interacting with fluorescence-emitting sites of the carbonized polymer quantum dots to quench the fluorescence of the carbonized polymer quantum dots. The photo-responsive composite material can realize information recording by zoningexposure of different regions to control fluorescence intensity of the different regions in an ultraviolet exposure process; the recorded information has certain stability under sunlight; and information destruction can be realized through overall exposure. The photo-responsive composite material has good biocompatibility and low environmental toxicity, and can be used as an anti-counterfeit label.

The invention discloses a preparation method of a quantum dot light-emitting diode, the quantum dot light-emitting diode is a positive device, and the method comprises the following steps: providing an anode; forming a hole function layer on the surface of the anode; forming a layer of short-chain ligand compound on the surface of the hole functional layer; and forming a quantum dot light-emittinglayer on the surface of the short-chain ligand compound. According to the invention, stable quantum dots can be obtained, the recombination of electron/hole pairs in excitons can be greatly improved,and the device efficiency is improved. Meanwhile, the ligand exchange method disclosed by the invention has the advantages of simple steps, short operation time, capability of effectively avoiding influence on other film layers and the like.

The invention discloses organic optical iridium coordination compounds and application thereof in an organic electro-generated white or orange optical device. The orange optical iridium coordinate compounds have a structural formula as formula 1 or formula 2 which is shown in the specification, wherein R1 can be trifluoromethyl or pentafluoroethyl, R4 can be trifluoromethyl or pentafluoroethyl or R1=R4, R2 is selected from hydrogen, methyl, ethyl and halogen or halogen-substituted methyl or ethyl, R3 is independently selected from hydrogen, methyl, ethyl, halogen or halogen-substituted methyl or ethyl or R2=R3, and the halogen is fluorine, chlorine, bromine or iodine. The invention has the advantages as follows: a fluorine-containing modified iridium coordination compound can be used for effectively lowering vibrating frequency, reducing non-radiative transition and increasing electroluminescence efficiency; a film prepared by using a fluorine atom-containing modified coordination compound has better feature; self-quenching behaviors are restrained by steric hindrance of CF3; and charge transfer balance performance is increased by very good current carrier transmission performance, so that an efficient doped organic electro-generated luminescent device can be manufactured.

The invention discloses a preparation method of supermolecule composite nano particles. The method comprises the following steps of: dissolving TPE-m-COOH in an organic solvent to obtain a TPE-m-COOH solution; and mixing dendronized polymer Gn PAMAM and the TPE-m-COOH solution in the organic solvent, keeping the concentration of the TPE-m-COOH solution 1*10<-6> to 1*10<-4>M, wherein the molar ratio of amino of Gn PAMAM to carboxyl of TPE-m-COOH is definite, dispersing and standing to obtain the supermolecule composite nano particles. The supermolecule composite nano particles are strong in fluorescence emission performance; compared with tetraphenylethenes derivatives, the supermolecule composite nano particles have the advantages that fluorescence intensity is greatly enhanced, and the supermolecule composite nano particles can be used as novel luminescent materials; the preparation method is simple and mild in condition; and the supermolecule composite nano particles are easy to prepare.

The invention discloses a piezochromic light-emitting sensor film formed on the basis of carbon dots and hydrotalcite and a preparation method thereof. The film is prepared from three raw materials, namely 3-aminobenzenesulfonic acid, layered double hydroxide and polyvinyl alcohol. The film prepared by the invention has dual emission (fluorescence and phosphorescence) behaviors of CDs, and when apressure sensing test is carried out, the film has a linear relationship with the pressure in the aspects of fluorescence and phosphorescence; after the film is pressed, the film can return to the original state through heating in a short time; after the film is irradiated for 1h under UV light, the fluorescence intensity and the phosphorescence intensity of the film are only reduced to about 80%of original values; good sensitivity, reversibility and light (fluorescence and phosphorescence) stability to external pressure are shown. The film with dual emission performance greatly improves thesensitivity of the sensor.

The invention provides a method for improving the 2microm waveband fluorescence emission of rare earth ion doped germanate glass. A trivalent rare earth metal oxide is utilized to control the ratio ofnon-bridging oxygen to bridging oxygen in the multi-component germanate laser glass to realize controllable adjustment of the degree of freedom of a glass network structure, thus improving the dopingconcentration and dispersibility of rare earth luminescent ions in matrix glass, reducing rare earth luminescent ion clusters, acquiring enhanced 2microm waveband fluorescence emission, ensuring thematrix glass good crystallization resistance and machining performance and low phonon energy, and providing a key matrix material for development of high-gain 2microm waveband active optical fiber.