174 results about "Double perovskites" patented technology

The invention discloses a preparation method of lead-free double perovskite nanofibers capable of efficiently photocatalytic reduction of CO2 at room temperature. The method comprises the following steps: fully dissolving cesium bromide, silver bromide and bismuth bromide in an organic solvent to obtain a precursor solution, adding a ligand and a polymer into the precursor solution, fully magnetically stirring to obtain a spinning solution, and preparing a nanofiber product by utilizing an airflow spinning technology. The airflow spinning technology is creatively adopted to enable the lead-free double perovskite quantum to grow on the nanofiber, a large number of catalytic reaction sites are provided, and the catalytic activity is remarkably improved. According to the method, large-scale preparation of the lead-free double perovskite nanofibers is achieved at the room temperature, controllability and high stability are achieved, operation is easy, the method is suitable for the field of photocatalytic CO2 conversion and the like, and a new thought is provided for sustainable energy development.

The invention is suitable for the technical field of inorganic luminescent materials, and provides a fluorescent powder material based on a double-perovskite structure and a preparation method and application thereof. The general chemical formula of the fluorescent powder is Ca2AlNbO6: xEu < 3 + >, wherein x is a molar fraction of 0.06 to 0.30; the excitation spectrum coverage range of the fluorescent powder under the condition of monitoring the emission wavelength of 615 nm is 260-500 nm, and the emission main peak is located at 615 nm; when x is equal to 0.18, the quantum efficiency under the excitation of 396nm ultraviolet light is greater than or equal to 91%, and the red light emission ratio is greater than or equal to 85%. According to the invention, Ca2AlNbO6 double perovskite is taken as a substrate, and a red fluorescent powder material with wide-spectrum excitation and high quantum efficiency is designed through Eu < 3 + > high-concentration doping and local symmetry regulation and control design engineering, so that the characteristics of high quantum efficiency, efficient red light emission, wide-spectrum excitation and excellent concentration quenching resistance are realized.

The invention relates to Eu (II) doped double perovskite red fluorescent powder as well as a preparation method and application thereof, and belongs to the technical field of inorganic luminescent materials. According to the red fluorescent powder capable of being excited by the blue light, disclosed by the invention, high-performance red light emission is realized by doping Eu < 2 + > with an oxide Sr2B1-xB 'O6 (wherein B is lutetium (Lu), B' is tantalum (Ta) or niobium (Nb), and x is greater than or equal to 0.01 and less than or equal to 0.10 as a matrix). The novel red fluorescent powder can be applied to white light LED illumination. When the fluorescent powder is used in combination with green light or yellow light fluorescent powder in the prior art, efficient white light is expected to be realized under the excitation of blue light, so that the color rendering performance of a white light LED is absolutely improved.

The invention discloses a preparation method of an all-inorganic vacancy ordered double perovskite luminescent material, and relates to the technical field of lead-free perovskite luminescent materials. The preparation method comprises the following steps: putting the raw materials CsCl and MoCl5 into a polytetrafluoroethylene lining, and mixing; then adding CeCl3 or TeO2, adding hydrochloric acid as a solvent, and stirring for one hour to fully and uniformly mix; and finally, putting the polytetrafluoroethylene lining into a cylinder sleeve of a reaction kettle, putting into a drying oven for reaction, slowly cooling to room temperature in the drying oven after the reaction is finished, cleaning with absolute ethyl alcohol, and drying to obtain the lead-free perovskite material. The prepared full-inorganic vacancy ordered double-perovskite luminescent material can emit broadband near-infrared light with the highest peak of about 990nm under the excitation of ultraviolet and blue light, and can be used in near-infrared imaging.

The invention belongs to the technical field of X-ray detection, and particularly relates to lead-free two-dimensional double perovskite, a preparation method of the lead-free two-dimensional double perovskite and an X-ray detector manufactured based on the perovskite. The lead-free two-dimensional double perovskite is applied to X-ray detection. According to the preparation method, histamine dihydrochloride (C5H11Cl2N3Cl), silver chloride (AgCl) and bismuth trioxide (Bi2O3) are mainly used as raw materials, a mixed solution of hydrobromic acid (HBr) and hypophosphorous acid (H2PO2) is used as a solvent, a single crystal material ((C5H9N3) 2AgBiBr8 single crystal) is prepared through a hydrothermal method, and the two sides of the single crystal are coated with silver paste to serve as electrodes, so that the direct type X-ray detector is obtained. The preparation method disclosed by the invention has the characteristics of simplicity, easiness in operation, low requirement on equipment, low cost, low energy consumption and suitability for expanded production.

The invention relates to a preparation method of an A-site cerium-doped double perovskite catalyst and an application of the A-site cerium-doped double perovskite catalyst in catalytic oxidation of toluene, and belongs to the technical field of environmental catalytic materials. Aiming at the technical defects that a traditional noble metal catalyst is high in cost and the oxygen mobility of a perovskite material is insufficient, the double perovskite material is designed through A-site Ce < 3 + > / Ce < 4 + > doping and B-site Co / Mn bimetal collaboratively, and the chemical general formula is La2-xCexCoMnO6 (x is greater than or equal to 0 and less than or equal to 0.3). The catalyst shows remarkable advantages in catalytic oxidation of toluene: under the conditions that the mass space velocity is 18000 mL. (g.h) <-1 > and the toluene concentration is 2000 mg. M <-3 >, T50 (50% conversion rate temperature) is 223 DEG C, T90 (90% conversion rate temperature) is 243 DEG C, and the catalyst is superior to an undoped sample La2CoMnO6 catalyst. The preparation method of the catalyst is simple, the product selectivity is high, the stability is good, and the catalyst is especially suitable for efficient low-temperature catalytic degradation of methylbenzene.

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 discloses a double perovskite material and a preparation method and application thereof, the chemical formula of the double perovskite material is Cs2AErZBi1-ZX6, A is one of Ag, Na and K, X is one or two of halogen anions, and Z is more than 0 and less than 1. According to the double-perovskite material provided by the invention, monovalent A (one of Ag, Na and K) ions and trivalent Er and Bi ions are used for replacing divalent Pb ions in a conventional double-perovskite material, so that the toxicity of the double-perovskite material is greatly reduced, and regulation and control of a perovskite band gap are realized to obtain the optical characteristic of a near-infrared II region. The rare earth element Er regulates and controls the energy level of the transition metal element Bi, so that the double perovskite material can realize a luminescence peak with the luminescence center of 1542nm. A detector prepared from the double perovskite material provided by the invention can realize visible-near infrared band (447-1550 nm) detection, I light / I dark in a visible light region can reach 104, and particularly, I light / I dark in 1550 nm and 1310 nm is greater than 102.

The invention belongs to the field of microwave catalysis, and particularly relates to a red-mud-based perovskite catalyst and a preparation method and application thereof.The A site of the catalyst is rare earth metal element bismuth, the B site of the catalyst is transition metal element iron, an iron source is red mud, and other transition metal ions are adopted to carry out partial substitution modification on the B site. The preparation method comprises the following steps: dissolving rare earth metal salt, transition metal salt and citric acid in deionized water; adding red mud into the solution obtained in the step S1, and uniformly dispersing; and S2, heating and stirring the mixed phase obtained in the step S2 to a gel state, and drying and calcining the gel to obtain the red mud-based perovskite catalyst. Compared with the prior art, the red mud-based double-perovskite catalyst is prepared by taking industrial waste red mud as an iron source and combining a sol-gel method with B-site partial substitution modification, the red mud-based double-perovskite catalyst shows excellent catalytic degradation performance in the aspect of antibiotic wastewater treatment, and the degradation efficiency of gatifloxacin within 9 min can reach 92% at most.

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.

The invention relates to the technical field of application of perovskite solar cells, and discloses a lead-free wide-band-gap double-perovskite solar cell, a preparation method thereof and an electronic price tag. According to the lead-free wide-band-gap double-perovskite solar cell provided by the invention, the optical band gap of the lead-free double-metal perovskite layer is in the range of 1.8 eV to 2.2 eV. Therefore, the lead-free wide-band-gap double-perovskite solar cell can be ensured to effectively absorb visible light and an indoor light source with a specific wavelength, not only can the energy of the indoor light source be utilized to the greatest extent, but also a relatively high open-circuit voltage can be maintained under low light intensity, and further relatively high photoelectric conversion efficiency of the lead-free wide-band-gap double-perovskite solar cell in an indoor weak light environment can be ensured. In addition, by adopting the non-lead perovskite material, the risk of heavy metal pollution is reduced, the method is green and environment-friendly, and large-scale production is easier.

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.

The invention relates to the technical field of photochromism, in particular to a preparation method of double perovskite halide Cs2AgInCl6 doped Mn < 2 + > ion photochromic powder, and the preparation method of the white photochromic powder comprises the following steps: S1, weighing: weighing required amounts of AgCl and InCl3 on an analytical balance; s2, a MnCl2. 4H2O solution with the concentration of 1 mol / L is prepared, and the amount of the needed MnCl2. 4H2O solution is calculated according to different doping amounts; and S3, firstly proportioning AgCl, InCl3 and MnCl2. 4H2O solutions, heating, stirring and reacting in hydrochloric acid until the solutions are dissolved, stirring for 10 minutes, then adding CsCl, heating and stirring for 20 minutes, and centrifugally drying to obtain a sample. According to the invention, a chemical synthesis method is utilized, and manganese ions are doped in double perovskite halide Cs2AgInCl6, so that an obvious photochromic phenomenon is realized; the photochromic performance is regulated and controlled through an experimental method and the Mn < 2 + > doping concentration. And meanwhile, the exploration range of the inorganic halide photochromic material and the application range of the double perovskite halide are expanded.

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 present invention discloses a Cr 3+ -doped hexafluoride near-infrared fluorescent material and a preparation method thereof. The chemical composition formula of the material is: K2LiMF6:xCr 3+ , where M is one of Al, Ga or In, and x is the molar percentage coefficient of the doped Cr 3+ ions relative to the M 3+ ions, and 0 < x ≤ 0.09. The fluorescent material K2LiMF6:xCr 3+ disclosed by the present invention has a stable cubic double perovskite structure and can achieve broadband near-infrared emission with ultra-high thermal stability under visible light excitation. It can be used to prepare a broadband near-infrared light source device to realize the functions of night vision and vein imaging. The preparation method of the K2LiMF6:xCr 3+ material disclosed by the present invention is a hydrothermal method, which is carried out in an aqueous solution. This method has simple operation and mild reaction conditions and is suitable for large-scale industrial production.

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 present invention provides a bionic structure ceramic catalyst, and the bionic structure ceramic catalyst includes "mesophyll", "vein" and "epidermis" structures; the "mesophyll" is the main structure, which is composed of one of perovskite structure, double perovskite structure or Ruddlesden-Popper structure; the "vein" is a network structure located inside the "mesophyll", the "epidermis" is a coating layer located on the surface of the "mesophyll", and the "vein" and "epidermis" are cubic fluorite structure or perovskite structure. The "epidermis" structure located on the surface of the "mesophyll" has abundant oxygen vacancies, which is beneficial to the processes of oxygen adsorption, dissociation and entering the lattice during the oxygen catalysis process. The network-like "vein" structure located inside the "mesophyll" provides a fast channel for the conduction of oxygen ions, making the catalyst have excellent oxygen ion conduction ability.

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.