494results about How to "Excellent fluorescence performance" patented technology

The present invention relates to the technical field of organic light-emitting materials, and in particular relates to an organic electroluminescent material and a light-emitting device thereof. The organic electroluminescent material is selected from the compounds as shown in Formula I. A rigid molecular structure is obtained by forming of a push-pull electron coplane of electron donating Donor and electron-withdrawing acceptor, certain separation of HOMO-LUMO is obtained so as to obtain narrow FWHM and high transition rate constant Kr.

The invention relates to an alkali halide-doped perovskite light-emitting diode. The alkali halide-doped perovskite light-emitting diode comprises a substrate, a hole transmission layer, an active light-emitting layer, an electron transmission layer, an electrode modification layer and an electrode, wherein the thickness of the active light-emitting layer is 5-100 nanometers, the active light-emitting layer comprises perovskite and an alkali halide doped in the perovskite, the molecular formula of the perovskite is one or more of CsPbCl<x>Br<3-x>, CsPbBr<x>I<3-x>, MAPbCl<x>Br<3-x>, MAPbBr<x<I<3-x>, FAPbCl<x>Br<3-x> and FAPbBr<x>I<3-x>, x is equal to 0, 1, 2 or 3, and the alkali halide is one or more of LiCl, NaCl, KCl, RbCl, LiBr, NaBr, KBr, RbBr, LiI, NaI, KI and RbI. The invention also provides a fabrication method of the alkali halide-doped perovskite light-emitting diode. The fabrication method comprises the steps of forming the hole transmission layer or the electron transmissionlayer o the substrate; modifying an alkali halide-containing perovskite precursor solution used as the active light-emitting layer on the hole transmission layer of the electron transmission layer; sequentially forming the electron transmission layer, a negative electrode modification layer and a negative electrode on the active light-emitting layer or sequentially forming the hole transmission layer, a positive electrode modification layer and a positive electrode on the active light-emitting layer; and performing package.

The invention relates to magnetic fluorescent microspheres and a preparation method thereof. The particle size of the magnetic fluorescent microspheres is 5-10 mu m, the fluorescence excitation wavelength range is 400-700nm, and the fluorescence intensity is not reduced within 24h. The prepration method comprises the following steps: adding a swelling agent into monodisperse carboxylated polystyrene microspheres, and adding magnetic nano microparticles into a swelling system; shaking on a decolorization shaker for 12-48h; using mixed solution of cyclohexane and ethanol for cleaning sediment, and sequentially carrying out ultrasonic dispersion and centrifugal separation till supernatant liquid is colorless under an ultraviolet lamp; and saving a final sediment product in 1ml of liquor. Compared with the existing magnetic fluorescent microspheres, the magnetic fluorescent microspheres have the advantages of uniform and controllable diameter, good fluorescence stability, simple preparation process, multiple types of fluorescence codes and the like, and can not only carry out fast separation and purification on reactants by being applied in the biological macromolecular detection, but also simultaneously detect a plurality of target molecules in a sample to be detected in a reaction tube and a hole, thereby being widely applied in the fields of immunoassay, nucleic acid hybridization, genotype analysis and the like.

The invention discloses a rare earth doped yttrium oxide fluorescent nano-fiber and a preparation method thereof. The nano-fiber comprises yttrium oxide and rare earth oxide, wherein the yttrium oxide accounts for 70-99.9 percent by weight, and the rare earth oxide accounts for 0.01-30 percent by weight. The diameter of the rare earth doped yttrium oxide fluorescent nano-fiber is 50-1000nm, and the nano-fiber is provided with small holes or small balls with diameters being 5-80nm. The preparation method comprises the following steps: preparing electrostatic spinning solution, making the electrostatic spinning solution into a composite nano-fiber precursor with spinning polymer resin, yttrium salt and rare earth salt through electrostatic spinning equipment under high-voltage electrostatic electricity, drying the composite nano-fiber precursor with the spinning polymer resin, the yttrium salt and the rare earth salt, and calcining to obtain the rare earth doped yttrium oxide fluorescent nano-fiber. The prepared rare earth doped yttrium oxide fluorescent nano-fiber has the advantages of large specific surface area, high fluorescence, easy recovery and recyclable property, and is applicable to biological sensors, field emission displays and other fields.

The invention belongs to technical field of nanomaterials and discloses a method for solvothermal preparation of fluorescent carbon nitride quantum dots by adoption of melamine as a raw material. The method includes steps: a) calcining melamine in a muffle furnace at a high temperature, and grinding products into yellow graphite-phase carbon nitride powder; b) scattering the graphite-phase carbon nitride powder into an alcohol solvent, adding a certain amount of alkali liquor, dissolving ultrasonically, sealing in a reaction kettle, and reacting for a while at a high temperature; c) cooling to the room temperature, collecting filtrate after vacuum filtration, and dialyzing the filtrate in a dialysis bag with a certain molecular weight cutoff until the filtrate is neutral, so that the fluorescent carbon nitride quantum dots are obtained. The method is simple in process, easy in operation, low in cost and environment friendly, and the prepared fluorescent carbon nitride quantum dots are high in purity and yield, excellent in dispersity and stability and high in fluorescence intensity and have a potential application prospect in fields of bioimaging, solar cells and the like.

The invention relates to a method for quickly preparing carbon quantum dots emitting blue light and carbon quantum dots emitting green light. According to the method, an environmentally-friendly hydrothermal synthesis method is adopted, L-ascorbic acid and ethidene diamine serve as raw materials, deionized water serves as solvent, the carbon quantum dots emitting the blue light and the carbon quantum dots emitting the green light are formed by quick synthesis of the L-ascorbic acid at different temperatures, the purity of products reaches 99%, the water solubility reaches 99.5%, the particle diameter of the carbon quantum dots emitting the blue light is smaller than or equal to 6 nm, the particle diameter of the carbon quantum dots emitting the green light is smaller than or equal to 6.2 nm, and the carbon quantum dots are good in dispersity, good in water solubility, good in fluorescence, capable of being applied to fluorescence probes, biomedical imaging, printing inks and photovoltaic devices; the preparation method is advanced in process, precise and detailed in data, high in preparation speed, good in product purity and stable in light-emitting performance and is a very ideal method for quickly preparing the carbon quantum dots emitting the blue light and the carbon quantum dots emitting the green light.

The invention provides a core-shell-structure photomagnetic double-function nano composite material and a preparation method thereof. The preparation method comprises the following steps: preparing an NaGdF4:Yb,Tm upconversion fluorescent nanocrystal nuclear material by high-temperature pyrolysis; coating an active upconversion fluorescent layer made of the same material on the surface of the NaGdF4:Yb,Tm upconversion fluorescent nanocrystal nuclear material by high-temperature pyrolysis; and coating an Fe3O4 magnetic shell on the surface of the core-shell structure by high-temperature pyrolysis to obtain the NaGdF4:Yb,Tm@NaGdF4:Yb,Tm@Fe3O4 core-shell-structure photomagnetic double-function nano composite material. The composite material provided by the invention has strong upconversion luminescence property and magnetic properties; and the middle active fluorescent layer enhances the fluorescence intensity, inhibits the quenching effect between the nuclear material and the strong-magnetism shell material, and improves the fluorescence of the finally prepared photomagnetic double-function composite material of which the particle size is only 20nm or so.

The invention belongs to the technical field of nano material preparation and metal ion detection, and particularly relates to a nitrogen doped fluorescent carbon quantum dot and a preparation methodthereof. The preparation method for the nitrogen doped fluorescent carbon quantum dot comprises the following steps: preparing a mixed solution of carboxymethyl cellulose and ethanediamine; putting the mixed solution in a high-pressure reaction kettle to perform hydrothermal reaction to obtain a reaction solution; performing ultrasonic treatment on the reaction solution, centrifuging, and filtering to obtain filtrate; using super-pure water to perform dialysis treatment on filtrate, and freezing and drying a solid product obtained by dialysis to obtain powder, thereby obtaining the nitrogen doped fluorescent carbon quantum dot. The method is simple in preparation process, is green and environmentally friendly, is low in cost, is simple in equipment and is suitable for large-scale production; and the prepared carbon quantum dot has excellent performances of being good in water solubility, stable in fluorescence property, uniform in grain size, non-toxic and harmless, biocompatible and the like, so that the application field of the carbon quantum dot is expanded.

The invention relates to a sulfur quantum dot with fluorescence characteristic, a preparation method and applications thereof, wherein the sulfur quantum dot has a spherical structure, and sequentially comprises a core, an adsorption layer and a coating layer from inside to outside, the core is a sulfur nanometer core, the adsorption layer is a variety of sulfur ions, the coating layer is formed by a dispersing agent, and the particle size is 2-25 nm. In the prior art, the existing sulfur quantum dots are not fluorescent. According to the present invention, the nanometer sulfur sol prepared through the method has advantages of good water solubility, good fluorescence and good stability.

The invention discloses a nano probe material for imaging, which is capable of efficiently breaching blood-brain barriers. Firstly, a high temperature pyrolysis method is adopted for preparing inner core NaYF4:Yb/TM/Gd hydrophobic nano-particles, then an NaGdF4 shell is formed through epitaxial growth so as to form core/casing structured NaYF4: Yb/Tm/Gd and NaGdF4 nano-particles, then hydrochloric acid hydrophilic modification and sulfhydryl PEG modification are performed, and finally, the nano probe material is prepared through Angiopep-2 grafting, and is marked as ANG/PEG-UCNPs. The material can be used for efficient blood-brain barrier breaching, magnetic resonance imaging diagnosis and positioning before an cranial cavity glioma operation, near infrared fluorescence imaging in the operation and image mediating, the imaging effect is good, the sensitivity is high, the physiological system toxicity is low, and the material plays an important significance in successful clinic glioma removing operations and the development and the application of medical image diagnostic techniques.

The invention provides a fluorescent perovskite/graphene composite film and a preparation method thereof, wherein Li, Na, K, Rb, Cs, Mg, Ca, Ba, Sr, Pr, Nd, Gd, Sm metal salts or organic ammonium Halogen salt with polymer and oleic acid to form solution A; add metal halides of Pb, Ti, Al, Sn, Mn, Fe, Cu, Co, Ni, Zn, Ru, Cd, Zr, Pd, Bi, Ag Form solution B with oleic acid, oleylamine and polymer; add solution A and solution B to graphene suspension, and then add organic solvent II to obtain fluorescent ore titanium/graphene composite solution; finally obtain fluorescent calcium by electrophoretic deposition TiO/Graphene Composite Thin Films. The perovskite particles and graphite in the composite film prepared by the invention are evenly dispersed, have high stability, high fluorescence intensity, simple preparation method and strong selectivity, and can be used in the fields of solar cells and biomedicine.

The invention discloses a prepartion method of CdSe and CdSe-ZnSe nuclear shell quantum dots, first, adding Cd source into organic coating agent and so-solvent, heating to dissolve the Cd source, then cooling to obtain Cd precursor solution; second, adding Se powder into trioctylphosphine and the so-solvent, ultrasonic dispersion at room temperature to dissolve the Se powder to get Se precursor solution; third, mixing the Cd precursor solution with the Se precursor solution, sealing the mixed solution and heating to make it react at certain temperature, the cooling to get CdSe quantum dots original solution; fourth, adding Zn source into the organic coating agent and so-solvent, heating to 100-140 DEG for dissolving the Zn source, cooling to get Zn precursor solution; fifth, mixing the Zn precursor solution, Se precursor solution and CdSe precursor quantum dots original solution, sealing the mixed solution and heating to make it react at certain temperature, then cooling to get the CdSe-ZnSe nuclear shell quantum dots.

The invention discloses a series of fluorescent OLED materials, which have the structure as shown in a formula I. The materials shown in the formula I have delayed fluorescence property; the organic electroluminescent device prepared by utilizing the materials can obtain deep blue organic light emitting diodes, the noble metal phosphorescent materials can be replaced, the manufacturing cost of the OLED device is greatly lowered, the material synthesis and purification methods are suitable for large-scale production, and the materials are an ideal choice of a luminescent material of the organic electroluminescent device.

The invention relates to a 2,3'5,5'-diphenyl tetracarboxylic acid cadmium complex and a preparation method thereof and relates to the field of cadmium complex fluorescent materials. A chemical formula of the 2,3'5,5'-diphenyl tetracarboxylic acid cadmium complex is {[Cd2(bptc)(bih)(H2O)2].H2O}n, wherein bptc is 2,3',5,5'-diphenyl tetra formic acid anion ligand, and bih is 1,6-di(imidazole-1-) hexane. The preparation method of the 2,3'5,5'-diphenyl tetracarboxylic acid cadmium complex comprises the following steps: under hydrothermal condition, dissolving 2,3',5,5'-diphenyl tetra formic acid, an inorganic base, 1,6-di(imidazole-1-) hexane and a cadmium salt in water, adding the obtained mixed solution into a closed reaction still, heating to 120-160 DEG C at a speed of 10 DEG C per hour, performing heat preservation for 3 days, then cooling to room temperature under natural conditions, so that colourless massive crystals are generated, and then washing and drying, so that the target product, namely the 2,3'5,5'-diphenyl tetracarboxylic acid cadmium complex, is obtained finally. The 2,3'5,5'-diphenyl tetracarboxylic acid cadmium complex has stable fluorescence property and high yield, and the preparation method is simple, and has good repeatability.