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

The invention provides a nitrogen, phosphorus and sulphur doping or co-doping carbon dot and a batch controllable preparing method and application thereof. The method comprises the steps that a carbon source, a nitrogen source, a phosphorus source and a sulphur source are evenly mixed, and a mixture is obtained, wherein the molar ratio of C to N to P to S in the mixture is 1 to 0-0.8 to 0-0.4 to 0-0.4, and the contents of N, P and S are prevented from being zero at the same time; in the air, the mixture is heated to be fused, the reaction is carried out for 3 min to 60 min, natural cooling is carried out till the indoor temperature is reached, a reaction product is separated by a silicagel column, raw materials which do not react are removed, and the nitrogen, phosphorus and sulphur doping or co-doping carbon dot is obtained. According to the method, the technology is simple, the compound time is short, batch producing can be achieved, the doping amount can be adjusted and controlled accurately, the fluorescence color of the prepared carbon dot ranges from blue to green, the application can be achieved on bioluminescence marking and cell imaging aspects, and the good economic benefit and the application prospect are achieved.

The invention relates to the technical field of organic luminescent materials, in particular to an organic electroluminescent material and a luminescent device with the same. The organic electroluminescent material comprises selected chemical compounds shown as a general formula I or a general formula II. The organic electroluminescent material and the luminescent device have the advantages that electron pushing and pulling common planes are formed by an electron donating Donor and an electron sucking Acceptor, and accordingly rigid molecular structures can be obtained; HOMO-LUMO (highest occupied molecular orbits-lowest unoccupied molecular orbits) are separated from one another to a certain extent, and accordingly the organic electroluminescent material and the luminescent device are narrow in FWHM (full width at half maximum) and have high transition rate constants Kr.

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.

A light emitting unit and a liquid crystal display apparatus including the same are provided. The light emitting unit includes a light source unit which generates light, and a driving board which drives the light source unit. The light source unit includes a light source which generates the light, a container member which forms an opening therein and which contains the light source within the opening, and a fluorescent member mounted in the opening of the container member. The light source and the florescent member are spaced apart.

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 discloses a preparation method of carbon quantum dots with a high fluorescence property by using glycine and glucose as precursors. The method comprises using the glycine as a surface passivating agent, the glucose as a carbon source material and a hydro-thermal reaction vessel as a reaction platform, carrying out a high-temperature and high-pressure hydrothermal reaction, and removing residues and water through dialysis and freeze drying to obtain carbon quantum dot powder. The preparation method of the carbon quantum dots has characteristics of simple operation, low cost and easy mass production. The prepared carbon quantum dots have excellent properties of high fluorescence property, photobleaching resistance, adjustable light emission and good biocompatibility, can be successfully applied in live cell fluorescence imaging and flow cytometry analysis, and is broad in application prospect in biomedical fields.

The invention relates to a multifunctional nano composite material of a core-shell structure and in particular relates to a carbon quantum dot magnetic fluorescent difunctional nano material and a preparation method thereof. Magnetic particle Fe3O is taken as a core, chitosan and polyanionic-based cellulose are taken as shell material, a carbon quantum dot is taken as a fluorescent material, and the carbon quantum dot magnetic fluorescent difunctional nano material is obtained by adopting a layer-by-layer self-assembly method; the carbon quantum dot is coated by adopting a natural polymer material, so that no free carbon quantum dot is formed, and stability is improved; magnetic property and fluorescence strength can be regulated and controlled by virtue of number of layers of the shell material and the addition amount of the carbon quantum dot; the obtained magnetic fluorescent difunctional nano material has a broad application prospect in the biological medicine fields of cell marking and absorption, bioimaging, medicine detection and disease diagnosis, medicine carrying and the like.

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 preparing a polymer fluorescent microsphere. The method comprises the following steps of: 1, preparing polymer fluorescent microsphere liquid drops, namely dissolving a first polymer into a solvent, adding a fluorescent material into the solvent, magnetically and uniformly stirring the fluorescent material and the first polymer in the solvent to prepare a non-continuous phase, respectively putting the non-continuous phase and a continuous phase into injectors connected with a non-continuous phase inlet and a continuous phase inlet of a microfluid device, adjusting the flowing speeds of the two phases of solutions through a trace sample injection pump, so as to obtain the fluorescent microsphere liquid drops, and at a microfluid outlet, collecting the fluorescent microsphere liquid drops into a fluorescent microsphere receiving device; and 2, preparing the polymer fluorescent microsphere, namely drying the fluorescent microsphere liquid drops until the solvent is completely volatilized, then washing the fluorescent microsphere liquid drops by a washer, and cleaning the continuous phase of solution to finally obtain the polymer fluorescent microsphere. Equipment used by the method is simple and convenient to operate; the particle size of the microsphere can be adjusted by adjusting the flowing speeds of the continuous phase and the non-continuous phase; and the uniformity of the particle sizes of the prepared microspheres is high.

The invention relates to a preparation method of a europium-doped carbon quantum dot composite material. The preparation method comprises the following steps: preparing a compound of citric acid and europium, and preparing the europium-doped carbon quantum dot composite material by adopting a hydrothermal method. The preparation method provided by the invention has the following beneficial effects: the method is simple and practical, the europium-doped carbon quantum dot composite material is endowed with the characteristics of high fluorescence stability, small size and good biocompatibility without being subjected to secondary modification, and the europium-doped carbon quantum dot composite material is improved in fluorescence properties significantly and can be excited by near ultraviolet to emit the characteristic red light of europium.

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 discloses a preparation method for a molybdenum disulfide quantum dot. The method comprises the following steps: (1) dispersing molybdenum disulfide powder in absolute ethyl alcohol, adding 0.5 to 3mg / mL of sodium hydroxide into the solution, and performing ultrasonic and uniform mixing to obtain a mixed solution; (2) transferring the mixed solution into a reaction kettle, sealing the reaction kettle, reacting for 3 to 24h in an oven of which the temperature is 100 to 200 DEG C, performing natural cooling until the temperature is room temperature, performing filtration, and then collecting obtained filter liquid; (3) dialyzing the filter liquid obtained in the step (2) in a dialysis bag to be neutral, removing small impurity molecules, and performing drying to obtain the molybdenum disulfide quantum dot. The preparation method for the molybdenum disulfide quantum dot is simple in operation, environmentally-friendly and low in cost, process conditions are easy to realize, and the prepared molybdenum disulfide quantum dot is excellent in dispersity, water solubility and fluorescence. The molybdenum disulfide quantum dot has a potential application value in terms of photo-electronic devices, lithium ion batteries, biological imaging, photo-electronic catalysis and the like.

The invention relates to a preparation method of a covalence organic framework material for detecting trace water in an organic solvent. The preparation method adopts a solvothermal method. The preparation method comprises the following steps: mixing 1,4-dihydroxy terephthalaldehyde, 2,4,6-tri(4-amino phenyl)-1,3,5-triazine, acetic acid, o-dichlorobenzene or mesitylene, and N,N-diethylacetamide, and ultrasonically uniformly dispersing; transferring a tube with a reaction solution to an environment with the temperature of 120 DEG C to react for 3d; and centrifugally separating obtained red solids, and alternately cleaning the separated solids by using tetrahydrofuran and dichloromethane, and then drying to obtain the needed covalence organic framework material. The preparation method has the advantages that the covalence organic framework material prepared by the method is high in crystallization degree, good in heat stability and chemical stability, stable in fluorescence performance, high in sensitivity to the trace water in the organic solvent, and can be reused for multiple times, so that an effective way is provided for detecting the trace water.

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 relates to a preparation method of europium-doped hydroxyapatite (HAP) fluorescent nanoparticles, which comprises the following steps of 1) preparing a mixed aqueous solution of calcium chloride and europium chloride, controlling the molar ratio of Eu to Ca and Eu together at 0.1-4%, preparing an aqueous solution of disodium hydrogen phosphate, quickly pouring the aqueous solution of disodium hydrogen phosphate into the mixed aqueous solution of calcium chloride and europium chloride at room temperature, uniformly stirring and mixing, after reaction, centrifuging to obtain precipitates, washing the precipitates with deionized water, and then dispersing into the deionized water again; 2) adding a stabilizer, and performing ultrasonic dispersion treatment by use of a high-energy ultrasonic probe to obtain a stable suspension; 3) performing hydrothermal treatment on the suspension by use of a high-pressure sterilization pot to obtain a stable suspension of europium-doped HAP fluorescent nanoparticles. The method provided by the invention has the beneficial effects that effective control on the size of rare earth europium-doped HAP fluorescent nanoparticles can be realized while the crystallinity and fluorescence are improved, and the stable suspension of the europium-doped HAP fluorescent nanoparticles is obtained.

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 discloses a preparation method of water-soluble luminescent quantum dots for fingerprint appearance, belonging to the field of biomarkers. The chemical composition of the water-soluble luminescent quantum dots is InP / ZnS. The preparation method comprises the following steps: under the inert atmosphere, weighing and adding an indium source, a phosphorus source, a surface active agent and a methylbenzene solvent of proper amount at certain stoichiometric ratio into a reactor, wherein the heating temperature is 150-200 DEG C, reacting for 18-36 hours to obtain gray black solution; using methyl alcohol to clean for a plurality of times; putting products in a vacuum drying box at certain temperature, drying for 8-12 hours to obtain solid powder of InP; dissloving a certain amount of solid powder into an organic solvent, adding alkaline solution (pH is 7.5-10.5) containing mercaptoacetic acid and zinc ions, stirring for a period of time at the temperature of 40-60 DEG C; removing an upper organic layer and obtaining lower-layer water-phase solution; and taking a certain amount of solution, adding the alkaline solution containing the mercaptoacetic acid and the zinc ions, stirring for 0.5-1.5 hours under the irradiation of ultraviolet light and obtaining water-soluble InP / ZnS end products.

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 belongs to the technical field of luminescent materials, and in particular relates to a wideband ultraviolet-visible light exited near infrared fluorescent emitting material and a preparation method and application thereof. The preparation method comprises steps of: mixing oxides of Y<3+>, Al<3+>, Bi<3+>, La<3+> and Yb<3+>, H3BO3 and a Cr salt according to the constitution ratio of all the elements in a formula Y1-x-zMzAl3-y(BO34):Crx<3+>, Yby<3+>, wherein M is one or two of Bi<3+> and La<3+>, and 0<x<=0.2, 0<y<=0.2, and 0<=z<=0.2; adding absolute ethyl alcohol, grinding and drying; and heating the mixed power to be 1000 DEG C-1400 DEG C, and sintering for 3-8 hours. The excitation wavelength of the luminescent material is 350nm-650nm, and the luminescent material can better utilize solar energy and is an ideal near infrared conversion material for increasing the effect of silicon solar cells.

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 preparation method and application of carbon dots from beer as a main raw material. In the method, the carbon dots are separated and purified through sephadex gel chromatography and then are collected. The carbon dots can directly be used in living cell fluorescent imaging, and in addition, the carbon dots are mixed and stirred with adriamycin in water to support the adriamycin onto the carbon dots, which can be used for killing tumor cells. The beer carbon dots are low in cost, low in toxicity and simple in method, has good water solubility when the adriamycin is supported thereon, and can be used in the fields of tumor fluorescent markers and treatment as a fluorescent medicine carrier.

The invention discloses a fluorescent microsphere of a core shell structure. The fluorescent microsphere of the core shell structure comprises a macromolecule inner core with scattered fluorescent dye and a shell made of silicon dioxide materials, wherein the thickness of the shell is even, the diameter of the macromolecule core is 10-10000nm, and the thickness of the shell is 5-1000nm. The macromolecule core is mainly made of macromolecule materials. The fluorescent dye is one or more of perylene and derivatives of the perylene, pyrene and derivatives of the pyrene, fluorene and derivatives of the fluorene, triaryl amidogen and derivatives of the triaryl amidogen, pyrazolo quinoline and derivatives of the pyrazolo quinoline, triaryl boron and derivatives of the triaryl boron, and dye containing DCM structures. The invention further discloses a preparing method and application of the fluorescent microsphere of the core shell structure. The fluorescent microsphere of the core shell structure is even in grain size, good in biocompatibility and good in fluorescence property and is a material capable of being used for biological markers.

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 discloses a red fluorescent material and a method for preparing the same.The red fluorescent material is named as [Eu3K2 (FDA) 4 (NO3) 3 (MeCN)2]n, a molecular formula of the red fluorescent material is C28H14N5O29Eu3K2, a molecular weight of the red fluorescent material is 1418.55, and the FDA represents 2, 5-furan terephthalic acid.The method includes arranging the 2, 5-furan terephthalic acid, europium nitrate and potassium nitrate in a high-pressure reaction kettle; adding acetonitrile solution into the high-pressure reaction kettle; carrying out reaction under the condition of the temperature of 120 DEG C to obtain bulk crystals.Red fluorescent light with the intensity of 70000 a.u.can be generated when the red fluorescent material [Eu3K2 (FDA) 4 (NO3) 3 (MeCN)2]n is illuminated by incident light with the length of 396 nm.The red fluorescent material and the method have the advantages of simple process, easiness in controlling chemical components, good repeatability and high yield.

The invention discloses an ultraviolet double-wave excitation fluorescent transparent invisible anti-fake nano-paper preparation method which includes the steps: firstly, combining lanthanide complexes and ONFCs (oxide nano-cellulose fibers) to form fluorescent transparent nano-paper; secondly, printing fluorescent carbon dots on the nano-paper in a fixed-point manner to obtain double fluorescent transparent nano-paper with an invisible anti-fake tag. The novel fluorescent transparent anti-fake nano-paper with the invisible tag has double fluorescent effects under excitation of double-waveband ultraviolet. The prepared anti-fake nano-paper is highly transparent, the anti-fake tag cannot be identified in a visualized manner under visible light and has double-color fluorescent effects under specific ultraviolet wavelength, imitation difficulty is greatly improved, and the anti-fake performance is improved.

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.