65 results about "Cesium iodide" patented technology

The invention discloses a preparation method and application of washable tin-based perovskite quantum dots, and the preparation method comprises the following steps: mixing cesium iodide powder, tin iodide powder and mesoporous silica powder, and then placing the mixture in a plasma ball mill for ball-milling diffusion, cesium iodide and tin iodide react in a confinement space of mesoporous silica to generate a CsSn I < 3 >-coated SiO2 composite structure, CsSn I < 3 > quantum dots are dispersed and coated in the mesoporous silica, and the application of the tin-based perovskite quantum dots in the anti-ultraviolet textile fabric is provided. The method has the following beneficial effects that the purpose of remarkably improving the stability of the tin-based perovskite quantum dots and the washing resistance of the textile is achieved.

The invention belongs to the technical field of photovoltaic solar materials, and particularly relates to a high-conversion-efficiency perovskite precursor material and a preparation method thereof. The high-conversion-efficiency perovskite precursor material is composed of phenyl ammonium cesium composite cations, metal halide, an additive, a nuclear auxiliary agent and a solvent. By compounding phenylethyl ammonium iodide and cesium iodide, phenylammonium and cesium cations are introduced into perovskite crystal lattices, organic-inorganic balance of the material is optimized, phenylammonium promotes formation of a quasi-two-dimensional structure, and damp-heat stability is enhanced; cesium ions fill A-site gaps, so that crystal lattices are tighter, and the thermal stability and the photoelectric conversion efficiency are improved; the synergistic matching addition of the metal halide realizes band gap regulation and control and spectrum matching, and quaternary ammonium salt adjusts nucleation and grain growth, so that a uniform film structure is ensured, and defects are reduced; and guanidine salt passivates defects after crystal growth, stabilizes crystal lattices, and improves charge life and device efficiency.

The invention belongs to the technical field of photoelectric materials and devices, and particularly relates to a perovskite thin film and a preparation method and application thereof. A fluorine-containing phosphazene compound is used as a ligand and is mixed with a perovskite precursor solution composed of lead iodide, formamidine iodine and cesium iodide, spin coating is performed, the fluorine-containing phosphazene compound and part of formamidine cations form hydrogen bonds, part of formamidine cations are anchored at the bottom of a perovskite film, Cs-formamidine cations are uniformly distributed, and the perovskite film is prepared. Meanwhile, the fluorine-containing phosphazene compound and Pb < 2 + > form a coordinate bond, Pb < 2 + > defects are passivated, and the perovskite thin film is obtained through anti-solvent treatment and annealing treatment. The fluorine-containing phosphazene compound interacts with the components in the perovskite precursor solution, so that the nucleation rate of perovskite can be increased, the crystallization rate can be slowed down, the tensile stress can be eliminated, the perovskite does not enter crystal lattices, and the stability and crystallinity of the film are guaranteed. The perovskite thin film can be used for an inverted perovskite solar cell, and the performance and the stability of a device are improved.

The invention discloses a sulfaguanidine modified inorganic tin-based perovskite light-emitting diode and a preparation method thereof, and belongs to the field of luminescent material preparation, the preparation method comprises the following steps: preparing a perovskite precursor solution which comprises cesium iodide, stannous iodide, sulfaguanidine and an organic solvent; applying the perovskite precursor solution to a substrate to form a wet film; carrying out annealing treatment on the wet film so as to form a perovskite light-emitting layer containing CsSnI3 perovskite and sulfaguanidine; a hole transport layer is formed on an anode conductive substrate, and a perovskite light-emitting layer is adopted on the hole transport layer; and sequentially forming an electron transport layer, an electron injection layer and a cathode electrode on the perovskite light-emitting layer. The process is simple and suitable for popularization and application.

The invention discloses a preparation method of a high-quality perovskite thick film for an X-ray detector, and relates to the technical field of radiation detection materials and devices. The preparation method of the thick film comprises the following steps: preparing a precursor solution from lead iodide, cesium iodide, formamidine iodide, methylamine iodide, 4-guanidinobenzoic acid hydrochloride, N, N-dimethylformamide and acetonitrile; a bulk phase functional additive is introduced to optimize a large number of Schottky defects at the grain boundary of the perovskite thick film; depositing onto a heated conductive glass substrate using a spray coating technique; and in combination with a low-temperature solvent atmosphere annealing process, secondary growth of crystal grains and grain boundary healing are promoted, and a large-area polycrystalline thick film can be obtained.

The invention relates to a lead-free perovskite composite material, a preparation method thereof and application of the lead-free perovskite composite material in a resistive random access memory, and belongs to the technical field of preparation of the resistive random access memory. The lead-free perovskite composite material comprises a doped Sb element, the chemical formula of the lead-free perovskite composite material is Cs3Cu2I5: Sb, the molar ratio of Sb to Cu is (0.1-1): 1, the perovskite Cs3Cu2I5 is doped and modified through the element Sb, the content of iodine vacancy (VI) in cesium-iodine-copper perovskite can be reduced, the stability of conductive filaments can be improved, and therefore the resistance change performance of the resistive random access memory is improved.

The present invention discloses a perovskite active layer doped with a carbazole-based small molecule, and its preparation method and application. The preparation method includes: dissolving formamidinium iodide, cesium iodide, lead iodide, and methylammonium iodide in an organic solvent to obtain a cesium-formamidinium-methylammonium lead iodide alloy perovskite precursor solution of the ABX3 configuration; doping a carbazole-based small molecule dopant into the perovskite precursor solution; and preparing a carbazole-based small molecule-doped perovskite active layer by any one of spin coating, blade coating, or spray coating. By introducing the carbazole-based small molecule, the present invention effectively adjusts the energy level of the perovskite, improves the crystallinity of the perovskite thin film, and prepares a p-i-n type perovskite solar cell without a hole transport layer. The photoelectric conversion efficiency of the battery device prepared by this method exceeds 26.6%, and it exhibits excellent long-term operation stability.

The application belongs to the technical field of photovoltaic devices, and relates to preparation and application of a multifunctional organic additive doped CsSnI3 perovskite film; during preparation, a perovskite spin coating liquid is spin coated on an ITO glass substrate to form a precursor film, and the precursor film is subjected to annealing treatment to obtain a CsSnI3 perovskite film; the perovskite spin coating liquid is formed by adding stannous fluoride and 3-amino-pyrazine-2-carboxamide (3-APCA) to a perovskite precursor solution and stirring; the perovskite precursor solution is formed by dissolving cesium iodide and stannous iodide in an organic solvent; and the application is applied to solar cells, light-emitting diodes, photoelectric detectors, photoelectric catalysis and energy storage. The method introduces the multifunctional organic additive 3-APCA, realizes Sn 2+ oxidation inhibition, optimizes film crystallinity and passivates defects, and significantly improves the quality of the CsSnI3 perovskite film; and the application range is wide.

The invention relates to the field of perovskite quantum dot materials, and discloses a perovskite quantum material printing process which comprises the following steps: S1, synthesizing perovskite quantum dots through a solution method by using lead iodide and cesium iodide as precursors; s2, performing double coating on the surface of the perovskite quantum dot; s3, carrying out curing treatment on the coated perovskite quantum dot thin film; s4, the coated perovskite quantum dots are dissolved in a solvent; s5, the solution is printed on a substrate in an ink jet printing mode, and a printed film is obtained; and S6, a hot air drying box is used for drying the printing film. According to the perovskite quantum dot, the inner layer is coated with silicon nitride, and the outer layer is coated with silicon dioxide, so that the stability and the environmental influence resistance of the perovskite quantum dot are improved, the surface of the perovskite quantum dot is more effectively protected through the coating structure, the performance of the perovskite quantum dot can be prevented from being eroded by the external environment, and rapid decline of the material in a severe environment is avoided.

The application discloses a preparation method of a wide-bandgap perovskite photoactive layer, and comprises the following steps: S1, lead iodide powder, cesium iodide powder and ytterbium bromide powder are proportioned according to a proportioning molar ratio, and an inorganic target material is prepared by using a hot-press sintering process; S2, formamidinium hydriodide powder and methylammonium bromide powder are proportioned according to a proportioning molar ratio, and an organic target material is prepared by using a normal-temperature preparation process; S3, a pretreated substrate is placed on a magnetron sputtering sample table, the target materials prepared in steps S1 and S2 are respectively installed on corresponding radio frequency sputtering targets, and the background of a magnetron sputtering system is vacuumized; S4, high-purity argon gas is used as a sputtering gas, and a wide-bandgap perovskite thin film is prepared by using a magnetron co-sputtering method; the sputtering power of the inorganic target material prepared in step S1 is controlled, the sputtering power of the organic target material prepared in step S2 is controlled, and the thickness of the thin film is controlled, so that the high-quality thin film is prepared by using the differential target material preparation process.

The application discloses a preparation method and application of high-purity cesium iodide, which comprises the following steps: firstly, mixing an industrial-grade cesium source powder and an iodine source solution, and preparing a solid powder after vacuum rotary evaporation and drying; then repeatedly washing the powder by using a special detergent, removing impurities, and drying; sintering at a temperature of 200-350 DEG C; dissolving the sintered powder in deionized warm water, and cooling and crystallizing at 0 DEG C; and finally collecting and drying the crystallization product to obtain the high-purity cesium iodide (CsI) finished product. The CsI powder prepared by the application has a purity of more than 99.99%, can obtain more excellent comprehensive performance, and has a simple and controllable process, and has a wide application prospect in the field of perovskite solar cells.

The invention discloses a carbazolyl micromolecule doped perovskite active layer and a preparation method and application thereof, and the preparation method comprises the steps: dissolving formamidine iodide, cesium iodide, lead iodide and methylamine iodide in an organic solvent to obtain a cesium-formamidine-methylamine lead-iodine alloy perovskite precursor solution with an ABX3 configuration; the preparation method comprises the following steps: doping a carbazolyl micromolecule dopant into a perovskite precursor solution, and preparing the perovskite active layer doped with carbazolyl micromolecules from the precursor solution in any one mode of spin coating, blade coating or spray coating. By introducing carbazolyl small molecules, the energy level of perovskite is effectively adjusted, the crystallinity of the perovskite thin film is improved, the hole transport layer-free p-i-n type perovskite solar cell is prepared, the photoelectric conversion efficiency of the cell device prepared by the method exceeds 26.6%, and the cell device shows excellent long-term operation stability.

The invention relates to the technical field of lithium-sulfur batteries, and discloses a high-specific-volume lithium-sulfur battery which comprises a positive electrode material, a negative electrode material, a diaphragm and an electrolyte, wherein the electrolyte comprises an organic solvent, an organic lithium salt and an electrolyte additive, and the electrolyte additive is cesium iodide; the diaphragm comprises a carbon material, a polymer base material, a binder and a Lewis acid catalyst, wherein the Lewis acid catalyst is molybdenum disulfide. The electrolyte additive contained in the electrolyte of the lithium-sulfur battery is combined with the Lewis acid catalyst in the diaphragm, so that the rapid conversion of sulfur species can be realized, meanwhile, the Lewis acid catalyst is ensured to always keep high activity, and the high-performance lithium-sulfur battery is effectively constructed.

A preparation method and application of a perovskite film, which are used to solve the technical problem of how to have good stability while having good photoelectric conversion efficiency for the existing perovskite film. An inorganic halide salt containing bismuth, an N,N-dimethylformamide solution, hydroiodic acid and raw materials are used to prepare an intermediate material containing bismuth. Using this intermediate material as a raw material, together with an inorganic halide salt containing lead, cesium iodide and an N,N-dimethylformamide solution as raw materials, a precursor solution is prepared. The perovskite film prepared from this precursor solution has a perovskite crystal structure of ABX3. In the perovskite film of the present invention, the A site is occupied by CS and DMA, and the B site is occupied by Pb and Bi. The perovskite film in the present invention has good stability, and at the same time, the photoelectric conversion rate can exceed 10%. At the same time, a black perovskite thin film can be obtained at a temperature of 80 to 150 °C or below. The present invention is mainly used in the technical field of optoelectronic functional materials and devices.

The invention discloses a preparation method of polycation black-phase perovskite microcrystal powder, and belongs to the technical field of new energy and photoelectric materials. The method comprises the following steps: dissolving formamidine iodide (FAI), cesium iodide (CsI), lead iodide (PbI2) and an accelerant n-propylamine hydrochloride (PACl) in an alcohol solvent according to a designed molar ratio to prepare a 0.2-2 mol.L <-1 > uniform solution, and heating and stirring to form a black precipitate; and quickly filtering, washing by using an alcohol solvent to remove the residual additive, and carrying out vacuum drying to obtain the high-purity black-phase microcrystalline powder. The prepared powder has uniform Cs / FA distribution, does not contain any yellow phase, remarkably inhibits cation segregation, improves the crystallization quality and phase stability, is simple in preparation process, is easy to remove auxiliary agent residues, and can be widely applied to preparation of photoelectric devices such as high-efficiency perovskite solar cells and the like.

The invention discloses a bismuth-based perovskite photosynapse transistor and a preparation method thereof, and the bismuth-based perovskite photosynapse transistor is of a layered structure, and sequentially comprises a silicon dioxide / silicon substrate layer, a bismuth-based perovskite light absorption layer doped with stannous iodide, a semiconductor channel layer, and a source / drain electrode layer from bottom to top. The source / drain electrode layer comprises a source electrode and a drain electrode which are respectively arranged on two sides of the upper surface of the semiconductor channel layer; in the preparation process, bivalent tin ions of stannous iodide with relatively strong Lewis acidity compete with trivalent bismuth ions of cesium iodide in a precursor, so that rapid reaction of cesium iodide and bismuth iodide is prevented, the crystallization speed of the bismuth-based perovskite film is slowed down, and unstable tin-iodine bonds can be broken through annealing treatment after combination, so that the performance of the bismuth-based perovskite film is improved. Therefore, the crystallization quality of the bismuth-based perovskite film is regulated and controlled; part of bivalent tin ions in the bismuth-based perovskite light absorption layer are easily oxidized by a DMSO solvent in annealing treatment to form tetravalent tin ions to generate tin vacancies, and the tin vacancies of the bismuth-based perovskite light absorption layer are used for increasing the number of photogenerated charges captured by the bismuth-based perovskite photosynapse transistor. According to the invention, the film forming quality and the carrier lifetime of the bismuth-based perovskite can be improved, so that the conductivity variation range of the device is expanded.

The invention provides a nitrogen-defect g-C3N4 / CsCu2I3 composite material as well as a preparation method and application thereof, and belongs to the technical field of preparation of nano heterogeneous materials. A preparation method of a nitrogen-defect g-C3N4 / CsCu2I3 composite material comprises the following steps: dissolving cesium iodide and cuprous iodide in anhydrous acetonitrile, and carrying out a stirring reaction at 50-70 DEG C for 4-6 h to obtain a CsCu2I3 precursor solution; adding g-C3N4 into the CsCu2I3 precursor solution, and reacting for 10-14 hours at the temperature of 50-70 DEG C to obtain a crystallization solution; and dropwise adding diethyl ether into the crystallization solution, carrying out anti-solvent crystallization, aging, washing and drying to obtain the nitrogen-defect g-C3N4 / CsCu2I3 composite material. The nitrogen-containing defect rod-like g-C3N4 / CsCu2I3 binary nano heterojunction with good gas sensitive performance is prepared by the method disclosed by the invention.

The invention relates to a perovskite precursor solution, a perovskite thin film, a preparation method of the perovskite thin film and a photovoltaic module. The perovskite precursor solution comprises a perovskite precursor, an additive and a mixed solvent; the perovskite precursor is prepared from formamidine hydriodate and lead iodide; the additive comprises cesium iodide and methylamine hydrochloride; the mixed solvent is prepared from N, N-dimethyl formamide, N-methyl pyrrolidone and cyclohexyl pyrrolidone. The composition of the perovskite precursor solution is blended, the high-quality perovskite thin film with the micro-suede surface is spontaneously formed in the perovskite crystallization process, the micro-suede surface structure can increase the contact area between a perovskite layer and a subsequent functional layer, a tight mechanical interlocking effect is generated between the micro-suede surface structure and the interface of the functional layer, and the performance of the perovskite thin film is improved. Therefore, the interface adhesive force of the subsequent functional layer and the metal electrode is obviously improved, and the problem of performance degradation of the perovskite assembly caused by the packaging process is solved.

The invention provides a cesium iodide crystal detector packaging structure and method, and belongs to the technical field of high-energy physical detectors. The cesium iodide crystal detector packaging structure comprises two groups of optical fiber modules, two groups of optical fiber readout SiPM, two groups of crystal readout SiPM and cesium iodide crystals, the two groups of optical fiber modules are tightly attached to the upper surface and the lower surface of the cesium iodide crystal respectively and are orthogonally arranged; the two groups of optical fiber reading SiPMs are respectively arranged on the two groups of optical fiber modules and are used for reading photons propagating to the tail ends of the optical fibers; the two groups of crystal read-out SiPMs are respectively clung to the two side surfaces of the cesium iodide crystal, are orthogonally arranged and are used for reading out photons propagating to the side surfaces of the cesium iodide crystal. According to the invention, photon number measurement can be provided while position resolution is measured, and the energy resolution capability is improved; the structure optimization degree is high, and substance interference does not exist on an incident particle path; the structure is convenient to install, corresponding operation is adopted, and detector packaging can be effectively completed.

The invention provides a solar cell based on a Cu-doped lead-copper alloy perovskite light absorption layer and a preparation method of the solar cell, and the light absorption layer of the solar cell is a Cu-doped lead-copper alloy perovskite thin film Cs0. 05MA 0. 10FA 0. 85Pb1-xCuxI3, the preparation method of the lead-copper alloy perovskite thin film comprises the following steps: adding formamidine hydriodate, methylamine hydriodate, cesium iodide, lead iodide and cuprous iodide powder into a solvent, and uniformly stirring and mixing to prepare a perovskite precursor solution; the PbI2 powder and the CuI powder are uniformly mixed, the uniformly mixed precursor solution is spin-coated, annealing is carried out on a heating stage, the thin film is obtained, the ratio of the PbI2 powder to the CuI powder is 1-x: x, and x is equal to 0-10%. The copper-doped lead-copper alloy perovskite with the three-dimensional octahedral structure synthesized by the method has structural and thermodynamic stability and is high in fluorescence performance and light absorption performance, and the crystallization quality of a thin film is remarkably improved; when the perovskite thin film is used as a light absorption layer of the cell, a perovskite solar cell with high photoelectric conversion efficiency can be prepared, and the perovskite solar cell has excellent ultraviolet resistance and high temperature resistance stability.

The present invention discloses a method for preparing a Cs3Cu2I5:Tl scintillator film by ultrasonic spraying assisted by a monomer additive. The method comprises dissolving cuprous iodide, cesium iodide, thallium iodide or thallium chloride, hypophosphorous acid and a monomer additive in DMF in proportion to form a precursor solution, then uniformly ultrasonically spraying the precursor solution on a glass substrate heated at 120-150°C, and finally annealing the wet film together with the glass substrate at 120-150°C to obtain Tl + A 0.15% doping Cs3Cu2I5:Tl scintillator film was produced using ultrasonic spraying and the addition of a monomer additive to the precursor solution. This method produces a dense, uniform, and specifically oriented Cs3Cu2I5:Tl scintillator film with a thickness exceeding 100 μm. The film also exhibits significantly enhanced adhesion and good air stability.

The invention provides an organic-inorganic hybrid perovskite nanowire material, a preparation method thereof and a gas sensor, and relates to the technical field of semiconductor materials and devices. The preparation method comprises the following steps: mixing lead iodide, methylamine hydriodic acid / cesium iodide and phenylethylamine hydriodic acid / butylammonium iodide in a set molar ratio according to the metering number in the general formula of the organic-inorganic hybrid perovskite, and adding a perovskite benign solvent to obtain an organic-inorganic hybrid perovskite precursor solution; and dripping the organic-inorganic hybrid perovskite precursor solution on a substrate, exposing the organic-inorganic hybrid perovskite precursor solution in an anti-solvent atmosphere, and crystallizing to obtain the organic-inorganic hybrid perovskite nanowire material. The organic-inorganic hybrid perovskite nanowire material with a three-dimensional network structure is prepared by controlling the concentration of the perovskite precursor solution and the experimental temperature based on raw materials in a molar ratio required by a quasi-two-dimensional perovskite crystal, and the obtained product has a higher specific surface area.

The invention discloses a method for regulating wide-band gap perovskite crystallization through CsPb2Br5 and laminated photovoltaic application thereof, and particularly relates to the field of photoelectric materials and devices. Comprising the following steps: preparing a CsPb2Br5 nanosheet; the preparation method comprises the following steps: dissolving cesium iodide, formamidine hydriodate, lead iodide, lead bromide and CsPb2Br5 nanosheets in a solvent to obtain a perovskite precursor solution; wherein the perovskite precursor solution comprises two phases, namely a Cs0.2 FA < 0.8 > PbI < 1.8 > Br < 1.2 > perovskite precursor complex and a CsPb2Br < 5 >; and preparing the perovskite precursor solution into a perovskite thin film of the solar cell to obtain the solar cell. The crystal can be guided to uniformly grow along the vertical direction, the crystal boundary and defects are reduced, the crystal structure is optimized, and the stability and uniformity of the film are enhanced; and photo-induced halogen phase separation and defect formation can be inhibited, so that the photoelectric property and long-term stability of the perovskite thin film are improved.

The present application relates to the field of perovskite microcrystal, and particularly relates to a black-phase CsPbI3 perovskite microcrystal, a full-inorganic thin film and a preparation method thereof.The preparation method comprises the following steps: mixing cesium iodide, lead iodide and a solvent to obtain a precursor solution; mixing the precursor solution, a heterogeneous metal ion stress inducer and a perfluorinated organic ligand, and performing a reaction to obtain the black-phase CsPbI3 perovskite microcrystal.The preparation method of the full-inorganic thin film comprises the following steps: mixing the black-phase CsPbI3 perovskite microcrystal and a high-polarity solvent, and performing dispersion to obtain ink; coating the ink on a substrate, and performing annealing treatment to obtain the full-inorganic thin film.The present application rewrites the thermodynamic stability interval by introducing a lattice stress field in the microcrystal synthesis stage, and realizes low-temperature preparation of the full-inorganic thin film by using the phase template effect.

This invention belongs to the field of scintillator material preparation technology, specifically relating to a method for purifying high-purity cesium iodide and its application in the preparation of cesium iodide scintillator screens. The method involves sequentially mixing and heating cesium iodide-containing waste and residual materials to dissolve them, filtering and removing impurities, adsorption and removing impurities, concentrating and temperature-controlled crystallization, centrifuging, drying, and vacuum packaging. This process comprehensively removes solid particulate impurities, elemental iodine, and various trace metal ions from the raw materials, effectively preventing oxidation and deterioration during purification. The method is simple to operate, highly industrially feasible, and can purify waste materials to a high purity level that meets the requirements of high-performance applications. It allows for the reuse of waste materials at the same purity level, reducing production costs, alleviating raw material supply pressure, and complying with environmental protection requirements. Applying the high-purity cesium iodide obtained by this method to the preparation of cesium iodide scintillator screens using a vacuum thermal evaporation process ensures the excellent performance of the scintillator screens, making them suitable for high-end fields such as medical imaging and non-destructive testing.

The invention discloses a cesium iodide nanocrystalline composite chalcogenide glass ceramic and a preparation method thereof, the chemical formula of the cesium iodide nanocrystalline composite chalcogenide glass ceramic is xGa2S3-ySnS2-(1-x-y) CsI, x is more than or equal to 0.2 and less than or equal to 0.3, and y is more than or equal to 0.2 and less than or equal to 0.6; the preparation method comprises the following steps: preparing a glass mixture according to a chemical formula by taking simple substances Ga, Sn and S and a compound CsI as raw materials; placing the glass mixture in a sealed vacuum quartz ampoule, carrying out melt firing at 850-900 DEG C for more than 12 hours, taking out the glass mixture at 650-700 DEG C, and quenching to form glass; carrying out annealing treatment on the formed glass at 250-290 DEG C / min for 4-6 hours, and then cooling to room temperature at a rate of 0.05-0.2 DEG C / min; and carrying out heat treatment on the obtained matrix glass at 350-390 DEG C for 5-20 hours, and then carrying out furnace cooling to room temperature. The chalcogenide glass ceramic contains uniformly distributed CsI nanocrystals, has good thermal and chemical stability and mechanical strength, and can be used in the technical fields of X-ray detection and infrared thermal imaging.

The invention relates to the technical field of semiconductor light-emitting devices, and discloses a preparation method of a high-color-purity blue light LED, which comprises the following steps of: mixing cesium iodide and cuprous iodide and reacting to prepare a Cs3Cu2I5 nuclear material; the Cs3Cu2I5 core material is placed in a shell layer precursor solution containing a gallium source to be wrapped and then annealed, and core-shell structure fluorescent powder is obtained; preparing the fluorescent powder with the core-shell structure into slurry, coating a base material with the slurry layer by layer, and performing high-temperature treatment to form a fluorescent material film with Ga concentration gradient; and integrating an ultraviolet LED chip with the fluorescent material film to prepare the high-color-purity blue light LED. According to the invention, the core-shell passivation structure and the concentration gradient film are constructed, and the functionalized packaging resin is matched, so that the quantum yield, the color purity, the light extraction efficiency and the long-term working stability of the blue light LED are improved.

This invention discloses a method for preparing inorganic perovskite thin films assisted by cystamine dihydrochloride. This invention relates to the field of optoelectronic materials and devices, and includes the following specific steps: Step 1: Weigh cesium iodide, lead iodide, and dimethylamine hydroiodide as raw materials, select DMF as the solvent, and then slowly add these raw materials to the DMF solvent. Stirring is performed at room temperature to obtain an inorganic perovskite precursor solution. The advantages of this invention are: by selecting cesium iodide, lead iodide, and dimethylamine hydroiodide in the inorganic perovskite precursor solution, it provides the basic elements for constructing the perovskite crystal structure, ensuring that the thin film possesses basic optoelectronic properties. It enhances the adhesion between the thin film and the substrate, effectively alleviates stress caused by differences in thermal expansion coefficients, and greatly suppresses the structural phase transition of the thin film under high-temperature conditions, successfully solving the problem of a sharp decline in the optoelectronic performance of thin films at high temperatures in existing technologies.

A scintillation crystal can include a cesium halide that is co-doped with thallium and another element. In an embodiment, the scintillation crystal can include CsI:Tl, Me, where Me represents co-doped Sb and Bi. In a particular embodiment, the scintillation crystal may have a cesium iodide host material, a first dopant including a thallium, a second dopant including an antimony, and a third dopant including a bismuth.

The invention discloses a lead-tin perovskite thin film and a preparation method and application thereof, and particularly relates to the field of photoelectric materials and devices. Comprising a bottom-buried interface layer, a lead-tin perovskite layer and an upper interface modification layer which are sequentially arranged from bottom to top, the lead-tin perovskite layer is formed by a lead-tin perovskite precursor solution, and the lead-tin perovskite precursor solution comprises the following components: a two-dimensional perovskite single crystal, lead iodide, stannous iodide, methylamine iodine, formamidine iodine, stannous fluoride and cesium iodide; and the component of the two-dimensional perovskite single crystal is PEA2PbI4. A two-dimensional perovskite single crystal is added into a Pb-Sn perovskite precursor to serve as a heterogeneous nucleation site, Pb-Sn perovskite is guided to longitudinally grow in the direction perpendicular to a substrate, transverse grain boundaries are reduced, and the crystallization quality is improved; meanwhile, as a buried interface and an upper interface modification layer, efficient transmission and extraction of photon-generated carriers in a Pb-Sn perovskite thin film and high efficiency and stability of a Pb-Sn perovskite cell can be realized.