148 results about "Lead bromide" patented technology

The invention belongs to the technical field of preparation of semiconductor nanomaterials and discloses a single-size CsPbX3 perovskite nanocrystalline preparation method. The method includes: adding cesium carboxylate solution into N2 protected lead bromide solution to realize reaction for obtaining single-size CsPbBr3 perovskite nanocrystalline; scattering the single-size CsPbX3 perovskite nanocrystalline into normal hexane, and gradually adding lead chloride solution or lead iodide solution drop by drop to realize reaction for obtaining single-size CsPbBr3 perovskite nanocrystalline. The single-size CsPbX3 perovskite nanocrystalline preparation method has the advantages of simplicity in operation, easiness in size adjustment of products, component controllability and the like.

The invention discloses a preparation method for a cesium lead bromide inorganic perovskite thin film and a photovoltaic device based on the cesium lead bromide inorganic perovskite thin film. An unstable yellow oblique-phase CsPbI3 thin film is prepared by employing a one-step solution method and then is converted to a stable black cubic-phase CsPbBr3 thin film by employing a Br2 steam thermal injection gas-phase deposition method. Gas-phase exchange reaction of halide ions is utilized, I<-> in CsPbI3 is substituted by Br<-> with smaller radius, the purpose of lattice shrinkage, phase changesuppression and stability improvement are achieved, the bottleneck problem that Br solubility of a traditional one-step solution method is limited can be effectively solved, and the problems that thethin film is easy to fall during immersion of a two-step solution method also can be prevented; and meanwhile, the prepared CsPbBr3 thin film is also used as a light absorption layer to prepare an FTO/c-TiO2/m-TiO2/CsPbBr3/C perovskite solar cell with an all-inorganic structure, the photoelectric efficiency of a battery in initial batch reaches 3.23%, and the battery shows favorable long-term stability.

The invention provides a preparation method of perovskite quantum dots. The preparation method comprises steps as follows: A), Cs2CO3, oleic acid and octadecene are mixed and subjected to a heating reaction under the condition of protective atmosphere, and a cesium oleate precursor solution is obtained; B), lead halide and octadecene are mixed and subjected to heating and heat preservation under the condition of protective atmosphere, after an oleic acid and oleylamine mixed solution is added and heated to 170-190 DEG C, an obtained mixed solution is mixed and reacts with the cesium oleate precursor solution, and the perovskite quantum dots are obtained, wherein the lead halide is selected from one or more of lead chloride, lead bromide and lead iodide. According to the preparation method, the coordination effect of surface ligands of the perovskite quantum dots of different halide ions directly synthesized at a higher temperature is more remarkable, so that stability and fluorescence quantum efficiency of the synthesized perovskite quantum dots are both guaranteed.

The invention discloses a method for preparing CsPbBr3 nanosheets with quantum size effects. The method includes dissolving cesium carbonate in oleic acid under argon filling conditions, and stirring the cesium carbonate and the oleic acid under heating conditions until the cesium carbonate is dissolved to obtain cesium oleate precursors; adding lead bromide, long-chain ligands and short-chain ligands into octadecene under argon filling conditions, carrying out reaction at the temperature of 100-150 DEG C until the lead bromide is dissolved, heating first reaction products until the temperature of the first reaction products reaches 120-150 DEG C, then injecting the cesium oleate precursors into the first reaction products, carrying out reaction for 5-15 s, then continuing to carry out reaction at the temperature of 100-130 DEG C for 1-5 min to obtain second reaction products and centrifuging the second reaction products. The method has the advantages that the transverse sizes of the CsPbBr3 nanosheets can be assuredly regulated and controlled in the range from 100 nm to 1 micrometer while the thicknesses which are equal to the thicknesses of a few atomic layers can be guaranteed; the thicknesses which are lower than the diameters of Bohr excitons can be kept, and accordingly the quantum size effects of the CsPbBr3 nanosheets can be reserved.

The invention relates to a two-dimensional perovskite single-crystal and a preparation method thereof. The chemical composition of the two-dimensional perovskite single-crystal material is A2PbBr4, wherein A is C4H9NH3+ or C3H7NH3+. Lead bromide and ammonium bromide with the ratio being 1:2 are adopted as raw materials, dimethylformamide is adopted as a solvent, chlorobenzene or a mixture of chlorobenzene and acetonitrile are adopted as an anti-solvent, and due to the anti-solvent mixing evaporation method, the large-size two-dimensional perovskite single-crystal is prepared under the room temperature atmosphere environment. The method is low in environment condition requirement, simple in process, applicable to preparing large-size crystal. The two-dimensional perovskite single-crystal has the good application prospect in the photoelectric field, and the efficient and simple preparation method has the great potential for single-crystal commercialization application.

The present invention provides an all-inorganic perovskite solar cell based on transition metal ions doped CsPbBr<3> and a preparation method and an application thereof. Specifically, the invention isthat conductive glass is first spin-coated with an electron transfer layer and subsequently spin-coated with a lead bromide solution mixed with transition metal ions, then is spin-coated with a cesium bromide solution repeatedly; the non-porous perovskite film with a high crystallinity and a large grain size is prepared; and finally the all-inorganic perovskite solar cell based on transition metal ions doped CsPbBr<3> is assembled by blade coating of carbon back electrode. The invention reduces the defect density in the perovskite film by doping transition metal ions, simultaneously the energy band structure is adjusted; the energy loss of charge migration is reduced; and the separation, extraction and transfer of photogenerated charges and charge recombination are reduced, thereby the photoelectric conversion efficiency and long-term operation stability of the cell are improved. The invention has the advantages such as simple and feasible preparation method, large optimization spaceof material combination, no noble metal back electrode or hole transporting layer and low cost.

The invention belongs to the technical field of display of fully-organic perovskite quantum dots, and discloses a CsPbBr3 (cesium-lead-bromide) perovskite quantum dot fluorescent glass for display ofwide color gamut and a preparation method and application thereof. The CsPbBr3 perovskite quantum dot fluorescent glass comprises the following components in percentage by mole: 0 to 45% of SiO2 (silicon dioxide), 0 to 45% of GeO2 (germanium dioxide), 30 to 40% of B2O3 (boron oxide), 2 to 8% of Al2O3 (aluminum oxide), 3 to 7% of MCO3 (metal carbonate), 1 to 5% of ZnO (zinc oxide), 5 to 15% of CsBr(cesium bromide) or Cs2CO3 (cesium carbonate), 2 to 10% of PbBr2 (lead bromide) or PbO (lead oxide), and 3 to 15% of NaBr (sodium bromide) or KBr (potassium-bromide), wherein M is Ca (calcium) or Sr(strontium); the sum of the components in percentage by mole is 100%. The CsPbBr3 perovskite quantum dot fluorescent glass has the advantages that the technology is simple, and the operation is easy;after in-situ crystallization, the quantum efficiency is higher, the light emitting stability is obviously improved, and the broad application prospect is realized.

The invention belongs to the technical field of preparation of optoelectronic materials and particularly relates to a copper-doped red-light perovskite quantum dot and a preparation method thereof. According to the method, a cesium salt or a formamidine salt, copper acetate, lead bromide and lead iodide are adopted as raw materials, organic acids and organic amine are adopted as ligands, and the stable and efficient copper-doped red-light perovskite quantum dot processable in solutions are rapidly synthesized through a thermal injection method. The stability of the red-light perovskite quantumdot is greatly improved through copper doping, and meanwhile, it is ensured that the high-fluorescence quantum efficiency of the quantum dot approaches 90%. According to the quantum dot, the absorption wavelength is increased along with the increase of the doping amount of copper, and a blue shift phenomenon of corresponding fluorescence emission wavelength of the quantum dot occurs. Obtained red-light perovskite quantum dot powder has high stability and can still be stored for more than 15 days under the condition that the air humidity is higher than 85%. The preparation method is simple andenvironmentally friendly, and the obtained red-light perovskite quantum dot can be applied to photoelectric devices such as light-emitting diodes, photoelectric detectors, laser devices and solar cells.

The present invention relates to a preparation method of dimension-controllable CsPbX3 perovskite nanometer crystals, and belongs to the technical field of preparation of a semiconductor nanomaterial.The method comprises: firstly, adding a cesium carboxylate solution to a lead bromide solution in N2 protection for a reaction, thereby obtaining CsPbBr3 perovskite nanometer crystal seeds; then, dispersing CsPbBr3 perovskite nanometer crystal seeds in hexane, injecting the obtained product to octadecene at different temperature to obtain CsPbBr3 perovskite nanometer crystals with different sizes; and finally, dispersing CsPbBr3 perovskite nanometer crystals in hexane, and gradually adding a lead chloride solution or a lead iodide solution drop by drop for a reaction to obtain other CsPbX3 (X=Cl, Ir) perovskite nanometer crystals. The method is simple to operate, the size of products is easy to adjust, and the components are controllable.

The invention relates to a preparation method of an adjustable luminescent CsPb2Br5 nanosheet, a product and application thereof. The preparation method comprises the following steps: under nitrogen protection, mixing cesium stearate, octadecene and oleic acid to prepare a caesium oleate solution; additionally, mixing lead bromide, octadecene, octylame and oleic acid, heating and stirring to obtain a PbBr2 precursor solution; and then adding the caesium oleate solution into the PbBr2 precursor solution, mixing and stirring to obtain the CsPb2Br5 nanosheet. Different sizes of CsPb2Br5 nanosheets are obtained by regulating and controlling the reaction temperature of preparing the PbBr2 precursor solution to be 100 to 140 DEG C, and the photoluminescence gradually changes into green light from blue light. The obtained CsPb2Br5 nanosheets can be used for preparing light-emitting diodes, solar cells or photoelectric detectors, and the light-emitting efficiency of high-monochromaticity green light LEDs constructed by preparing the CsPb2Br5 nanosheets reaches 34.49 lm/W.

The invention belongs to the field of materials, and specifically relates to a perovskite nanosheet material as well as a preparation method and application thereof. The preparation method of the perovskite nanosheet material comprises the following steps: (1) mixing cesium carbonate powder with octadecene and oleic acid, dissolving the cesium carbonate powder by heating to 100-130 DEG C under aninert atmosphere, rising the temperature of a system to 140-160 DEG C and reacting for 10-60 min to obtain a cesium oleic acid precursor; mixing iron bromide power with octadecene, oleic acid and oleylamine, dissolving, then adding lead bromide power into an obtained mixed solution, and dissolving the lead bromide powder by heating to 100-120 DEG C under an inert atmosphere so as to obtain an ironand lead mixed solution; and (2) heating the cesium oleic acid precursor to 80-100 DEG C, uniformly mixing with the iron and lead mixed solution, performing a thermal insulation reaction for 5 s-5 min at 120-140 DEG C, cooling and then performing centrifugal separation. Therefore, the obtained perovskite nanosheet material has relatively short light-emitting wavelength; the light-emitting peak position is at about 436 nm; the half peak width is only 14 nm; the light-emitting peak is fully symmetric; and the two-dimensional perovskite nanosheet material is very uniform in size and thickness, and is easy to control.

The invention belongs to the technical field of photoelectric functional materials and particularly relates to a phase-change-controllable totally-inorganic perovskite thin film preparation method anddevice application. The method comprises the steps that (1), precursor lead bromide and cesium bromide are placed into a vapor deposition device correspondingly, a substrate is placed in a depositionarea, and vacuum pumping is performed on the whole device; (2), an inert gas is introduced into the vapor deposition device; (3), the deposition temperature and deposition time are set, the deposition temperature is selected from 500-800 DEG C, and at the different deposition temperature, perovskite thin film has different composition and crystal forms. The phase-change-controllable totally-inorganic perovskite thin film preparation method and the device application adopt a chemical vapor deposition method, are simple in process condition, easy to control accurately and suitable for industrial production; meanwhile, the thin film has good uniformity and has good adhesiveness and spreadability with the substrate material, and the prepared optoelectronic thin film has broad application prospects; and by means of change of the deposition temperature, controllable growth of perovskite phase from CsPb2Br5 to CsPbBr3 is realized, and a photoelectric detector prepared on base of the perovskite thin film obtained by the phase-change-controllable totally-inorganic perovskite thin film preparation method shows good photoelectric response and switching characteristics.

The invention relates to a preparation method of a small-size high-stability perovskite nanocrystalline Cs4PbBr6, and belongs to the technical field of preparation of semiconductor nanomaterials. Thepreparation method comprises the following steps: firstly injecting a caesium carboxylate solution into a lead bromide solution at the temperature of 140 DEG C to 200 DEG C under the protection of N2,reacting, synthesizing a perovskite nano-block CsPbBr3 with the size of 3.8 nm to 11.8 nm, purifying the perovskite nano-block CsPbBr3, dispersing the perovskite nano-block CsPbBr3 by using octadecene, raising the temperature to 25 DEG C to 120 DEG C, injecting an ammonium bromide solution, reacting for 3-8 minutes, then centrifuging and purifying to obtain a nanoparticle Cs4PbBr6. The preparation method has the characteristics of easy operation, simple steps and rapid reaction, the raw materials are easy to get, the prepared particles Cs4PbBr6 are uniform in size, regular in morphology and excellent in stability, and the particle keeps unchanged even after a stock solution is placed in the air for a month.

The invention relates to a preparation method of silica-coated all-inorganic perovskite core-shell structure quantum dots. The preparation method comprises the following steps: completely dissolving cesium carbonate in n-caprylic acid to obtain a cesium precursor solution, dissolving lead bromide and tetra-n-octylammonium bromide in toluene to obtain a lead bromide/toluene solution; and then, sequentially adding an aminosilane coupling agent and the cesium precursor solution into the lead bromide/toluene solution, stirring for reaction, and separating and drying an obtained product to obtain the target product. Compared with the prior art, the preparation method disclosed by the invention is simple and loose in condition, the fluorescence characteristic of the prepared product is not reduced, the stability is greatly improved compared with that of pure CsPbBr3, and the product can be used as fluorescent powder to be packaged into a photoelectric device for application.

The invention provides an organic/inorganic hybridized tin-lead mixed perovskite material and a preparation method thereof. A dimethyl ammonium bromide solid, a lead bromide solid and a tin bromide solid are mixed, added to an N, N-dimethyl formamide solvent and uniformly stirred, and then a reaction solution is obtained; the reaction solution is subjected to pulse electromagnetic field treatment, dropped on a conductive glass substrate and subjected to low-speed spin-coating and high-speed spin-coating respectively, a perovskite film is formed and subjected to vacuum drying in a vacuum drying box, and then the organic/inorganic hybridized tin-lead perovskite film is obtained. The material and the method have the advantages that the preparation process of the method is simple, the preparation stability is good, the cycle is short, the process cost is effectively reduced, the content of a lead element can be reduced, environment pollution can be reduced, the light absorptivity of the material is higher, and the material can be used for manufacturing of a solar cell light absorption layer.

The invention discloses a method for preparing a halide perovskite caesium lead bromide quantum dot based on liquid-phase laser irradiation. All-inorganic halide perovskite is a novel fluorescent nanomaterial with relatively low toxicity, low cost and high quality, and has good application prospects in the fields of illumination, display, communication, sensing, biological imaging and detection, etc. The method of the invention adopts liquid-phase laser irradiation, uses caesium lead bromide powder as a raw material and oleylamine and oleic acid as ligands, and synthesizes the caesium lead bromide quantum dot with a single-phase structure, good crystallinity and uniform morphology and size in an organic solvent. Compared with conventional preparation methods for caesium lead bromide nano-materials, the method in the invention has the advantages of wide sources of raw materials, simple operation, mild experimental conditions, no need for heating and protective gases, high reproducibility, etc.

The invention discloses a synthetic method for a high-stability halogen perovskite quantum dot film based on multi-layer coating and used for X-ray imaging, and belongs to the technical field of preparation of inorganic semiconductor luminescent materials. The synthetic method comprises the following steps: preparing a Cs(OA) precursor solution, and performing a reaction on lead bromide, octadecene, oleic acid and 3-aminopropyltriethoxysilane to obtain a clear solution; pouring the clear solution instantaneously into the Cs(OA) precursor solution, and performing cooling and vigorous shaking toroom temperature to obtain a quantum dot solution; preparing a lead oleate precursor solution; preparing a first-layer coated quantum dot solution in different states; preparing a second-layer coatedquantum dot solution; preparing a multi-layer coated monodisperse quantum dot solution; and preparing the quantum dot film. According to the synthetic method provided by the invention, through the inorganic halogen perovskite quantum dot multi-layer coating strategy, a monodisperse core-shell structure is formed, the toxicity is reduced, and the stability of perovskite quantum dots is improved.

The invention discloses a preparation method of a cesium lead bromide quantum dot/carbon nitride nanosheet photocatalyst. The preparation method comprises the following steps: 1, preparing cesium leadbromide quantum dots by an anti-solvent process; 2, preparing a bulk phase graphite phase carbon nitride powder through recrystallization and thermal polycondensation of polyurea; and 3, adding the cesium lead bromide quantum dots while ultrasonically stripping the bulk phase graphite phase carbon nitride to prepare the cesium lead bromide quantum dot/carbon nitride nanosheet photocatalyst material in one step. The cesium lead bromide quantum dot/carbon nitride nanosheet photocatalyst is prepared by simple one-step ultrasonication, and the obtained composite photocatalyst material has good water stability, and overcomes the defect of instability the cesium lead bromide quantum dots in water. The composite photocatalyst improves the utilization rate of visible lights and inhibits the recombination of photogenerated electrons and holes, so the composite photocatalyst can efficiently photocatalyze the degradation of tetracycline hydrochloride in water under the irradiation of visible light.

The invention discloses a method for preparing a layered structure inorganic perovskite negative electrode material by using a gas phase method, and relates to the technical field of preparation of lithium ion battery negative electrode materials. The method comprises: sequentially or simultaneously depositing lead bromide and cesium bromide on a copper foil substrate under a vacuum condition through a gas phase method, and carrying out heating annealing in air to obtain the layered structure inorganic perovskite negative electrode material. According to the present invention, according to theprinciples of physical vapor deposition and chemical vapor deposition, inorganic lead bromide and cesium bromide are used as raw materials and are deposited on the surface of the copper foil substrate through heating evaporation, the evaporation rate, the deposition thickness and the thickness ratio are regulated, and the subsequent annealing treatment is performed to prepare the dense and uniform pure inorganic perovskite material. With the applications of the layered structure inorganic perovskite negative electrode material in lithium ion battery negative electrode materials, good thermodynamic stability and excellent physical and chemical properties can be achieved, and the process is simple.

The invention discloses a method for preparing a two-dimensional inorganic perovskite negative electrode material by solid-liquid phase reaction. The method comprises the following steps of adding lead bromide and cesium bromide into N,N-dimethylformamide, heating and stirring, and drying under the vacuum condition, so as to obtain precursor powder; mixing the precursor powder and the lead bromide, performing ball milling, grinding, and drying under the vacuum condition, so as to obtain the two-dimensional inorganic perovskite negative electrode material. The method for preparing the two-dimensional inorganic perovskite negative electrode material by the solid-liquid phase reaction has the advantages that by adopting the simple solution synthesizing and ball milling technology, the precursor material is in contact with an interface in the high-energy impacting process, and then reacts, so as to obtain the inorganic perovskite material with high crystallizing degree; the problems of complicated preparation technology and higher cost due to graphitizing and carbon coating required by the existing negative electrode material of the lithium ion battery at high temperature are solved; the large-batch synthesizing preparation purpose is realized, the production process of the negative electrode material is greatly shortened, and the material cost is greatly reduced.

The invention discloses a room-temperature A-site doping method for APbX3 perovskite quantum dots. The method comprises the following steps: 1) dissolving lead bromide and an organic ligand in toluene, performing stirring to dissolve the lead bromide and the organic ligand in order to obtain a lead precursor, and dissolving cesium carbonate, and formamidine acetate, methylamine acetate or guanidine carbonate in a long alkyl chain organic acid to obtain a doped A-site precursor, wherein the doped A-site precursor includes a doped A-site precursor salt; 2) injecting the doped A-site precursor obtained in step 1) into the lead precursor obtained in the step 1), and carrying out a full reaction to obtain a quantum dot stock solution; and 3), centrifuging and purifying the quantum dot stock solution obtained in step 2) to obtain A-site doped APbX3 perovskite quantum dots. The room-temperature A-site doping method for APbX3 perovskite quantum dots improves the performances of perovskite QLEDdevices by doping the A-site Cs matrix of the CsPbX3 with formamidine, methylamine or guanidine. The fluorescence quantum yield PLQY of the doped APbX3 quantum dots reaches 90% or above, and the efficiency (EQE) of the QLEDs of the doped APbX3 quantum dots reaches 10 or more.