108 results about "Double perovskites" patented technology

The invention provides near-infrared adjustable double-perovskite type mechanoluminescence fluorescent powder as well as a preparation method and application of the near-infrared adjustable double-perovskite type mechanoluminescence fluorescent powder. The expression general formula of the double perovskite type mechanoluminescence fluorescent powder is Sr2M1-xSbO6: xCr < 3 + >, wherein M is Al, Ga, Sc, In or Y; x is equal to 1%-7%. The preparation process of the fluorescent powder comprises the following steps: a, weighing strontium carbonate, an oxide of M, antimony pentoxide and chromium sesquioxide according to the element proportion in the chemical general formula Sr2M1-xSbO6: xCr < 3 + >; b, mixing the weighed raw materials, and uniformly grinding to obtain a mixture; and c, carrying out high-temperature calcination on the obtained mixture to obtain the near-infrared adjustable double perovskite type mechanoluminescence fluorescent powder. By regulating and controlling the components of the substrate, the emission main peak can be adjusted from 780nm to 946nm. The fluorescent powder provided by the invention can show a self-recovery near-infrared stress luminescence characteristic without pre-irradiation under continuous stress stimulation, is simple to prepare and convenient for industrial batch production, and has a wide application prospect.

The invention relates to a machine learning and physical priori knowledge constraint-based double perovskite halide material layer-by-layer screening method, equipment and a medium, and aims at solving the problems of low efficiency, large candidate space and insufficient multi-performance balance of a traditional data-driven screening framework, and constructing a cascade screening method taking spectral maximum efficiency (SLME) as a guide. Discovery of a high-precision photovoltaic material is realized through a progressive decision chain strictly following the sequence of space group symmetry, SLME, band gap characteristics and thermodynamic stability. A candidate material space is constructed based on an element coordination environment and a charge neutrality principle, the structural stability is primarily screened by using a new tolerance factor, then layer-by-layer screening is performed sequentially through a machine model, and finally a high-performance material is screened out. Compared with the prior art, the invention provides a layer-by-layer screening method which takes SLME as a core and is constrained by physical priori knowledge, and multi-dimensional efficient screening from structure, optics, electricity to stability is realized.

The invention discloses a double-perovskite thin film material, a preparation method thereof and a double-perovskite solar cell, and relates to the technical field of perovskite materials. The double perovskite thin film material comprises A2BCX6 type double perovskite, A is an alkali metal cation, B is a monovalent metal cation, C is a trivalent metal cation, and X is a halogen anion; the additive is a compound comprising a benzene ring and at least two sulfydryl substituted at different positions of the benzene ring. According to the embodiment, the composite center of the interior and interface of the double-perovskite thin film material can be reduced, the nucleation density in the preparation process of the double-perovskite thin film is reduced, the double-perovskite film layer has high crystallinity and larger grain size, the grain boundary in the film layer is reduced, the grain boundary defect is passivated, and the performance of the double-perovskite thin film is improved. And the photoelectric conversion efficiency of the solar cell containing the double perovskite thin film material can be improved.

The invention relates to the technical field of luminescent materials, in particular to tungsten-doped double perovskite and a preparation method and application thereof. The first aspect of the invention is to provide tungsten-doped double perovskite, the chemical formula of the tungsten-doped double perovskite is Cs2Sn1-xCl6: xW < 4 + >, and x is greater than or equal to 0.1% and less than or equal to 5%. The invention further provides a preparation method of the tungsten-doped double perovskite, which comprises the following steps: mixing a Cs-containing compound, a Sn-containing compound, a W-containing compound and concentrated hydrochloric acid, heating, cooling, separating, washing and drying to obtain the tungsten-doped double perovskite. The third aspect of the invention is to provide application of the tungsten-doped double perovskite in the fields of near-infrared LEDs, night vision, safety monitoring or nondestructive analysis. The fourth aspect of the invention is to provide an optoelectronic device, and the luminescent material of the optoelectronic device adopts the tungsten-doped double perovskite.

The invention relates to an A-site high-entropy double perovskite anode material and a preparation method and application thereof. The chemical general formula of the anode material is (Ln < 1 > < 0.2 > Ln < 2 > < 0.2 > Ln < 3 > < 0.2 > Ln < 4 > < 0.2 > Ln < 5 > < 0.2 >) A 'B2O5 + delta (wherein delta is greater than or equal to 0 and less than or equal to 1). Wherein Ln1 to Ln5 are five different lanthanide rare earth elements and jointly occupy the A site, and the A site elements are any five of Sm, Pr, Nd, La, Gd, Eu, Er, Dy, Te, Yb, Y and Sc; the A'site is composed of any two elements of Ba, Sr and Ca; and the B site is Co. According to the invention, the double perovskite structure can be effectively stabilized, the number of catalytic active sites of an OER reaction is increased, the TEC of a cathode is effectively reduced, the electro-catalysis ORR reaction activity is increased, the performance of hydrogen production by electrolysis of water of a single cell is improved, and the output stability of the cell is effectively enhanced.

This invention belongs to the field of solid oxide fuel cell technology, specifically relating to a method for preparing and applying a highly catalytically active and stable high-entropy double perovskite direct ammonia solid oxide fuel cell anode. The anode material is characterized by having the general chemical formula Sr₂Fe₃. x Sn y Co y Nb y Zr y Mo z O 6‑δ Wherein, 0.75≤x≤1, 0.15≤y≤0.25, 0.25≤z≤0.4, 0≤δ≤1, and δ represents the oxygen vacancy content. The material of this invention exhibits excellent catalytic activity and outstanding stability, effectively solving the Sr₂Fe₂O₃ problem. 1.5 Mo 0.5 O6 anode material exhibits structural instability at high temperatures (above 800℃) and tends towards perovskite-like Sr3FeMoO2. 6.5 The problem of transformation. The material of this invention and the electrolyte material La. 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 2.85 The material exhibits good chemical compatibility, and solid oxide fuel cells fabricated using this invention demonstrate excellent electrochemical performance and superior long-term stability under both H2 and NH3 conditions. The material is simple to prepare, possesses excellent performance, and has broad application prospects.

This invention belongs to the field of photocatalytic materials and new energy technology, and discloses a method for preparing a Rh-modified Cs₂AgBiBr₆ / CdS heterojunction photocatalyst. The method includes: preparing Cs₂AgBiBr₆ nanoparticles via antisolvent precipitation, preparing CdS nanorods via hydrothermal method, subsequently constructing a heterojunction through in-situ growth, and loading a Rh co-catalyst using photoreduction. This invention effectively overcomes the technical bottleneck of structural instability of traditional perovskites in polar solvents by introducing a Cs₂AgBiBr₆ double perovskite with a rigid lattice structure. Experiments show that the catalyst retains its structural integrity after immersion in ethanol for 168 hours and under different atmospheres, and exhibits excellent performance in the photocatalytic dehydrogenation of ethanol, with a hydrogen production rate as high as 49.15 mmol·g⁻¹. ‑1 ·h ‑1 The apparent quantum efficiency at 420 nm is 22.5%, and it remains stable during a 60-hour continuous reaction. This invention provides a new strategy for developing efficient and stable lead-free perovskite photocatalytic systems.

This invention relates to a medium-temperature solid oxide fuel cell cathode material and its preparation method. The invention employs a sol-gel method to synthesize perovskite oxide Pr 0.1 Ba 0.9 Co 0.8 Zr 0.1 Y 0.1 O 3‑δ The material contains PrBaCo2O with a double perovskite structure. 5+δ BaCo with single perovskite structure 0.8 Zr 0.1 Y 0.1 O 3‑δ Two phases. Multiphase Pr 0.1 Ba 0.9 Co 0.8 Zr 0.1 Y 0.1 O 3‑δ The sample achieved a conductivity of 100 S / cm within the operating temperature range of a mid-temperature solid oxide fuel cell. ‑1 At 700℃, the polarization impedance is 0.06 Ωcm. 2 This meets the requirements for cathode materials in solid oxide fuel cells. The electrolyte-supported single cell achieved a maximum power density of 710 mW / cm³ at 800℃. ‑2 The single cell underwent continuous and stable discharge at a constant current for 200 hours without performance degradation, demonstrating excellent output performance stability. In summary, perovskite oxide Pr 0.1 Ba 0.9 Co 0.8 Zr 0.1 Y 0.1 O 3‑δ It is a potential cathode material for intermediate-temperature solid oxide fuel cells.

The invention discloses a composite anode material, an anode, an electrolyte-supported solid oxide fuel cell and a preparation method, and relates to the technical field of cells. The composite anode material comprises a double-perovskite anode material and a metal oxide, the double-perovskite anode material comprises YSZ (Yttrium Stabilized Zirconium) and a double-perovskite material, wherein the double-perovskite material is at least one of PrBaMn2O5, PrBa < 0.5 > Sr < 0.5 > Co < 1.5 > Fe < 0.5 > O5, Sr2CoMoO6, LaBaMn2O5, LaBaCo2O5, Sr2FeMoO6, Ba2FeMoO6, Sr2Fe < 1.5 > Mo < 0.5 > O6 and PrBaFe2O5; and the metal oxide is at least one of NiO, Co3O4 and Fe3O4. The preparation method has the beneficial effects that various metal oxides are mixed into the classic double-perovskite anode material, so that the conductivity of the double-perovskite anode can be improved, the polarization impedance of the double-perovskite anode can be reduced, and finally, the relatively large power density improvement of the cell is realized.

The invention belongs to the field of photocatalysis, and particularly discloses a perovskite composite photocatalyst for photocatalytic ethanol dehydrogenation and application. The composite photocatalyst takes a CdS nanorod as a carrier, a Cs2AgBiBr6 double perovskite active component formed by CsBr, AgBr and BiBr3 precursors is loaded on the surface of the CdS nanorod through a vacuum in-situ growth method, and a Pt, Rh or Ni metal cocatalyst can be further loaded. The method comprises the following steps: dispersing a CdS nanorod and a perovskite precursor in a mixed organic solvent, carrying out vacuum freezing-air exhaust circulation treatment, and removing the solvent under a heating condition to prepare the composite photocatalyst. When the photocatalyst is used for an ethanol photocatalytic dehydrogenation reaction under an anaerobic condition, hydrogen, acetaldehyde and acetal can be efficiently generated under the irradiation of visible light. According to the method, the photo-generated charge separation efficiency and the reaction stability are remarkably improved, and a new way is provided for ethanol high-valued conversion.

The application discloses a polarization LED device with adjustable light-emitting color and a preparation method thereof. The preparation method comprises the following steps: mixing cesium oleate, erbium oleate, indium acetate, bismuth acetate, silver acetate, benzoyl chloride, dioctyl ether, oleic acid and oleylamine in proportion, then heating to 120-170 DEG C under a nitrogen atmosphere, reacting for 1-5 min, and stopping the reaction; adding a mixed solution of cyclohexane and ethyl acetate into the reaction solution, centrifuging, collecting the precipitate, repeating the operation, obtaining quantum dots, dispersing the quantum dots in cyclohexane to obtain a quantum dot solution; mixing the quantum dot solution with an inorganic polysilazane solution, ultrasonic dispersing, then heating the mixed solution to 70-90 DEG C, stirring and reacting for 10-15 h, so that the inorganic polysilazane is hydrolyzed to form a dense silicon oxide shell, and a slurry is obtained; preparing the slurry into a film, attaching the film to an LED device, and the polarization LED device with adjustable light-emitting color is obtained. The doping concentration is controlled by introducing a bait ion into a double perovskite system and utilizing energy transfer to realize light-emitting color.

This invention relates to a method for producing phenolic compounds by pyrolysis of lignin catalyzed by a double perovskite, comprising: preparation of a MOF precursor; calcination of the MOF precursor prepared in step one to prepare a MOF-based double perovskite AA' with tunable morphology, specific surface area, and pore structure. 1‑x K x B₂O₆, where A is a rare earth metal, A' is an alkaline earth metal, and B is a transition metal, the molar ratio of the metals in MOFs-based double perovskites is A:A':K:B = 1:(1- x ): x :2, where 0.01≤ x ≤0.40; MOFs-based double perovskite catalytic pyrolysis of lignin to produce phenolic compounds, the phenolic compounds in the liquid phase product include phenols, guaiacol, and syringol, with a total selectivity ≥65%; regeneration of double perovskite. This invention utilizes double perovskite catalytic pyrolysis of lignin to produce phenolic compounds, which can convert lignin into high-value-added chemicals.

Aspects of the present disclosure generally relate to a new class of compositions utilized for detecting short-wave infrared (SWIR) light, to devices including the compositions, and to photodetectors including the compositions. Aspects of the present disclosure also generally relate to processes for forming the compositions, the devices, and the photodetectors. In an aspect, a process for forming a SWIR device is provided. The process includes forming a precursor solution comprising: a first compound (AX), a second compound (BX), a third compound (CX3), a nitrogen-containing compound, and a solvent. The process further includes: dispersing the precursor solution on a substrate surface of a substrate and annealing the dispersed precursor solution on the substrate at an annealing temperature that is from about 100° C. to about 300° C. to form a film composition comprising: the nitrogen-containing compound or ion thereof; and a lead-free double perovskite represented by Formula (I): A2BCX6 (I).

The invention relates to the technical field of lithium ion battery materials, and discloses a double perovskite oxide coated ternary positive electrode material as well as a preparation method and application thereof. The invention provides a double-perovskite oxide coated ternary positive electrode material, which comprises a nickel manganese lithium cobalt oxide ternary positive electrode material and a coating layer coated on the surface of the nickel manganese lithium cobalt oxide ternary positive electrode material, the coating layer comprises a double-perovskite oxide, and the double-perovskite oxide comprises La2NiMnO6. The double perovskite oxide coated ternary positive electrode material provided by the invention has excellent cycle performance, excellent rate capability and voltage stability. The invention also provides a preparation method of the double perovskite oxide coated ternary positive electrode material, the preparation method is mild in condition and easy to amplify, and a solid technical basis is provided for manufacturing the positive electrode material of the lithium ion battery with high performance and long service life.

Described is a thin film comprising a Yb-doped double perovskite, wherein the double perovskite has the formula M2AYbxB(1-x)X6; wherein each occurrence of M independently represents Cs or Rb; A represents Ag or Cu; B represents Bi, In, Sb, or Ga; x has a value between 0.01 and 0.20; and each X independently represents F, Cl, Br, or I. Also described is a method of making the thin films. The thin film may be useful in photovoltaic devices.

The application discloses a kind of preparation methods of lead-free environmental protection Cs2TiBr6 double perovskite film, it includes the following steps: CsBr powder and TiBr4 Powder are added to beaker equipped with gamma-butyrolactone solvent and magnetically stirred to be completely dissolved, then slowly add anhydrous acetonitrile as anti-solvent and constant temperature heating is placed on heating table, after seed microcrystal precipitates, pour out solution, use acetone to flush seed microcrystal after, and dry after standing;Seed microcrystal, CsBr powder and TiBr4 Powder are added to N, N-dimethylformamide solvent, and be loaded into centrifugal tube and centrifuged, pour out supernatant after centrifugation and the precipitate is dried, obtain Cs2TiBr6 microcrystal;Cs2TiBr6 microcrystal is added to the mixed solution of cyclohexane and isopropyl alcohol with certain mass ratio, and magnetically stirred to make microcrystal fully dispersed, obtain Cs2TiBr6 precursor solution;Cs2TiBr6 precursor solution is added dropwise to substrate and spin-coated, then the substrate is placed on heating table and annealed, to obtain Cs2TiBr6 film.The advantages are that, compared with existing film preparation technology, 1) no need of thermal evaporation coating machine and double source co-evaporation process, low cost and simple process;2) will not corrode substrate material;3) the thickness of prepared Cs2TiBr6 film is 8-10 μm, suitable for use in optoelectronic devices.

The invention discloses a Ti / Nb co-doped layered double perovskite type oxygen electrode material and a preparation method and application thereof, the chemical general formula of the Ti / Nb co-doped layered double perovskite type oxygen electrode material is PrBaCo < 2-x-y > Ti < x > Nb < y > O < 5 + delta >, x is less than or equal to 0.2, 0 lt; y is less than or equal to 0.2, and delta is oxygen vacancy content. According to the Ti / Nb co-doped layered double perovskite type oxygen electrode material prepared by the method, on the basis of high intrinsic activity of PrBaCo2O5 + delta, through doping of Ti / Nb double elements, the proton conductivity of the oxygen electrode material is improved, element segregation is inhibited, and the thermal expansion coefficient is reduced, so that the oxygen electrode material has high electrocatalytic activity and operation stability.

The invention provides an application of a two-dimensional rare earth double perovskite material in preparation of a memristor, and relates to the technical field of memristors, the chemical general formula of the two-dimensional rare earth double perovskite material is (R3HQ) 4CeRb (NO3) 8, wherein the (R3HQ) 4CeRb (NO3) 8 is a monoclinic system, and the polar point group of the (R3HQ) 4CeRb (NO3) 8 is P21; and R3HQ is an (R)-3 hydroxyl quinuclidine ring organic cation. Two-dimensional rare earth double perovskite (R3HQ) 4RbCe (NO3) 8 is used as an active layer, and a memristor device is directly constructed. The memristor shows bipolar switching characteristics without electroforming, has long-term stability and good flexibility, and can bear hundreds of bending cycles.

The application discloses a lead-free halogen double-perovskite full-spectrum fluorescent powder and a preparation method thereof. 1‑x Cl6:xPt 4+ Wherein, M is one of Zr, Sn and Hf, 0

To specifically provide a double perovskite material, a manufacturing method of the same, and a reversible proton ceramic electrochemical battery, while relating to a field of the reversible proton ceramic electrochemical battery.SOLUTION: A formula of a double perovskite material is PrBa0.9Cs0.1Co2O6-δ, where δ represents an oxygen vacancy content. The present invention further provides a manufacturing method of the double perovskite material, and a reversible proton ceramic electrochemical battery containing the double perovskite material. The double perovskite material in which Cs+ is doped, that is provided by the present invention exhibits excellent stability, relatively low polarization impedance, and relatively high ORR / OER activation. The reversible proton ceramic electrochemical battery provided by the present invention exhibits excellent stability, electrocatalytic activation, and electrochemical performance.SELECTED DRAWING: Figure 11

The application discloses a first main group metal gradient doped Cs2NaBiCl6 perovskite material and a preparation method and application thereof, and belongs to the technical field of photocatalytic material for preventing and treating air pollution. The preparation method comprises the following steps: dissolving cesium chloride, sodium chloride, lithium chloride and bismuth chloride in hydrochloric acid and stirring uniformly; placing the mixture into a reaction kettle to perform hydrothermal reaction; after the reaction is completed, centrifuging, washing and drying are performed to obtain Cs2Na 1‑ x Li x BiCl6, wherein x is 0.1-0.5. The lithium-doped cesium-sodium-bismuth-chlorine double perovskite photocatalyst has stronger photocatalytic reduction capacity, and can greatly improve the activity of the lithium-doped cesium-sodium-bismuth-chlorine double perovskite in photocatalytic reduction of carbon dioxide, and the generation rate of carbon monoxide can reach 10.25 mu mol per hour ‑1 ·g ‑1 .

The application belongs to the technical field of X-ray photochromic technology, and discloses an X-ray irradiation color-changing material and application thereof.The X-ray irradiation color-changing material is a double perovskite halide Cs2NaInCl6 powder, the Cs2NaInCl6 powder is obtained by sequentially adding NaCl, InCl3 and CsCl into deionized water, dissolving, stirring and centrifugal drying; further, the obtained Cs2NaInCl6 powder is placed in a tube furnace, 5% H2+N2 mixed gas is introduced for heat preservation treatment, and the Cs2NaInCl6 powder with different initial colors can be obtained.The X-ray irradiation color-changing material prepared by the application has obvious color change under X-ray irradiation, the irradiation area changes from the initial color to yellow or yellow brown, the color change contrast is high, and the X-ray irradiation color-changing material can be used in the fields of information storage, anti-fake identification and X-ray visualization monitoring.

The application discloses a double perovskite material and a preparation method and application thereof, and the chemical formula of the double perovskite material is Cs2AEr Z Bi 1‑Z X6, wherein A is one of Ag, Na and K, X is one or two of halogen anions, and 0 < Z < 1. The double perovskite material provided by the application replaces divalent Pb ions in a conventional double perovskite material with monovalent A (one of Ag, Na and K) ions and trivalent Er and Bi ions, so that the toxicity of the double perovskite material is greatly reduced, the perovskite band gap is controlled, and optical properties in the near-infrared II region are obtained. Due to the regulation of the rare earth element Er on the energy level of the transition metal element Bi, the double perovskite material can realize a luminescent peak with a luminescent center of 1542 nm. The detector prepared from the double perovskite material can realize visible-near-infrared band (447-1550 nm) detection, wherein the visible light region I 光 / I 暗 can reach 10 4 , in particular, the I 光 / I 暗 of 1550 nm and 1310 nm is greater than 10 2 .

The invention relates to the technical field of fluorescent powder materials, in particular to a lead-free double-perovskite fluorescent powder material and a preparation method and application thereof, the chemical formula of the lead-free double-perovskite fluorescent powder material is Cs2ZrCl6: 1% of Te < 4 + > and 3% of Mo < 4 + >, and 1% of Te < 4 + > and 3% of Mo < 4 + > are doping proportions; the lead-free double-perovskite fluorescent powder material prepared by the invention can be applied to preparation of white light-near infrared LED devices and composite X-ray scintillator films; the lead-free double perovskite fluorescent powder material prepared by the invention can simultaneously realize high-efficiency white light emission, near-infrared emission and X-ray excited radiation luminescence, so that the spatial consistency and acquisition synchronism of multispectral images are ensured from a hardware source, and the problems of image pixel dislocation, resolution mismatch, high resolution ratio and the like caused by the use of various luminescent materials at present are solved. And the later image fusion processing flow is complex and time-consuming.

The invention belongs to the technical field of detection materials, and relates to a double-perovskite-based luminescent material, a preparation method thereof and application of the double-perovskite-based luminescent material in luminescent imaging or anti-counterfeiting. The molecular formula of the double-perovskite-based luminescent material is Cs2NaCrCl6: Tm < 3 + > / Yb < 3 + >, the molar doping concentration of Tm < 3 + > is 0.5-5%, and the molar doping concentration of Yb < 3 + > is 2-80%. The preparation method comprises the following steps: dissolving cesium chloride, sodium chloride, chromium chloride, thulium chloride and ytterbium chloride in water according to a stoichiometric ratio, uniformly mixing, carrying out a solution synthesis reaction, and evaporating to remove a solvent, thereby obtaining the product. The double-perovskite-based luminescent material provided by the invention can generate light with different colors, can realize multiple anti-counterfeiting, is simple in preparation process and low in cost, and is beneficial to realizing industrial large-scale production.

The invention discloses a hydrogen-based superconducting material Na2GaCuH6 with a double perovskite structure under normal pressure and a preparation method of the hydrogen-based superconducting material Na2GaCuH6. The material has an Fm-3m space group, the lattice constant is calculated and predicted through the first principle, and the material has the superconducting transition temperature of 42.04 K under the normal pressure condition. The material is composed of four common elements of Na, Ga, Cu and H, and the cost is low; the double perovskite structure is stable in thermodynamics and dynamics under normal pressure; the electro-acoustic coupling constant lambda is approximately equal to 0.98, and medium-intensity electro-acoustic coupling is achieved. Compared with an existing high-voltage hydride superconductor, the material can work without high-voltage equipment, and the preparation and application cost is greatly reduced; compared with a traditional normal-pressure superconductor, the superconductor has a higher Tc value. The material can be applied to the fields of low-temperature superconducting devices, superconducting magnets, quantum computing and the like, and has important scientific research value and application prospect.

The invention relates to the technical field of superconducting materials, and discloses a multi-element rare earth barium copper oxide high-temperature superconducting thin film and a preparation method thereof. In order to solve the technical problems that the pinning effect of an artificial magnetic flux pinning center of a high-temperature superconducting material is poor and the critical current density under a high magnetic field is low, the rare earth barium copper oxide is prepared by co-doping at least three rare earth elements at a rare earth site; an artificial magnetic flux pinning center of a perovskite oxide BaZrO3 and a double perovskite oxide Ba2YNbO6 is introduced into the rare earth barium copper oxide, and a multi-scale pinning system from the atomic scale to the nanoscale is formed in the superconducting thin film through atomic scale mismatch and introduction of the artificial magnetic flux pinning center; effective pinning of magnetic flux vortexes of different states and different sizes is achieved, and therefore the critical current density of the high-temperature superconducting material under the low-temperature high magnetic field is effectively improved finally.

The invention discloses a Cs2KYCl6-doped rare earth-based double perovskite WLED (White Light Emitting Diode) luminescent material, belongs to the technical field of luminescent materials, and is used for solving the technical problem that the luminous efficiency, warm white color product stability and reliability in a humid and hot environment of the WLED luminescent material in the prior art need to be further improved. The invention relates to a Cs2KYCl6 doped rare earth-based double perovskite WLED (White Light Emitting Diode) luminescent material, the WLED luminescent material is a luminescent nanosheet coated with polysiloxane, and the luminescent nanosheet has a chemical general formula Cs2K (Y < 1-x > Lnx) Cl6. According to the invention, the composition and doping amount of rare earth elements are optimized, the crystal growth process is controlled, and the luminescent nanosheets are compactly coated with the fluorine-containing polysiloxane sol, so that the high luminous efficiency of the WLED luminescent material and the stability of a warm white color product are effectively improved, and the reliability of the WLED luminescent material in a humid and hot environment is also improved.

The invention provides a lead-free double-perovskite solar cell and a preparation method and a characterization method thereof, and the method employs p-aminobenzoate molecules to modify lead-free double-perovskite CsAgBiBrcrystals, forms a perovskite thin film with a flat and uniform surface, improves the charge transmission and exchange efficiency at the surface of a perovskite light absorption layer, and at the same time, improves the photoelectric conversion efficiency of the perovskite light absorption layer. Functional groups in the p-aminobenzoate can be selectively coordinated with two sublattices in the double inorganic perovskite CsAgBiBr, so that ordered arrangement of the sublattices is promoted, and the photoelectric conversion efficiency and the stability of the lead-free double perovskite device are effectively improved. In addition, the CsAgBiBr film before and after aminobenzoate molecule modification is subjected to in-situ characterization through a Raman spectrum technology, and the optimization degree of the film is monitored in real time; meanwhile, in combination with electrochemical test data, a technical path for modifying and regulating the performance of the CsAgBiBr perovskite solar cell by the p-aminobenzoate is constructed. The technology provides an important research strategy and theoretical technology for performance improvement and quality control of the CsAgBiBr lead-free double perovskite-based photoelectric device.

Disclosed in the present invention is a preparation method for a surface plasmon enhanced Mn4+-doped double perovskite fluorescent powder, which preparation method comprises: S1, selecting specific A, B' and B'' source compounds, mixing same according to a stoichiometric ratio, adding zirconium oxide balls into a ball milling tank, subjecting the mixture to planetary ball milling for 3-8 hours, then placing the mixture into an alumina crucible, sintering same at 900-1300°C for 6-15 hours to obtain a matrix, cooling the matrix, and subjecting same to a particle size treatment and XRD detection; S2, selecting an Mn4+-containing compound, and subjecting same having a concentration of 0.1-5 mol% and the matrix to ball milling for 2-6 hours; and S3, subjecting a metal salt solution and the material obtained in the previous step to an ultrasonic treatment, so as to achieve a metal nano treatment. The luminous efficiency of the fluorescent powder of the present invention is significantly improved; the intensity can be improved by 30-50% compared with that of a traditional fluorescent powder; and color regulation and control are accurate, such that multicolor fluorescence emission can be achieved. The color saturation and luminous efficiency can be improved when the fluorescent powder is applied to a display technology; the color rendering index and luminous efficiency can be improved when the fluorescent powder is used for illumination; and the anti-counterfeiting effect in the anti-counterfeiting field is enhanced. In addition, the fluorescent powder has good chemical stability, and the preparation thereof is easy to control, which are beneficial for industrial production and multi-field application expansion.