81 results about "Hydroiodic acid" patented technology

The invention provides a method for preparing formamidine hydriodate through a one-pot method, formamidine hydriodate and application of formamidine hydriodate, and particularly relates to the technical field of perovskite photovoltaic cell precursor material preparation. The method comprises the following steps: adding an iodine elementary substance and a solvent into a reaction container, dropwise adding a reducing agent to carry out a first reaction, adding formamidine acetate in batches to carry out a second reaction at 0-10 DEG C after the reaction is completed, and carrying out post-treatment purification after the reaction is completed to obtain the formamidine hydriodate. The method directly selects the iodine elementary substance as the raw material, so that the use cost of the raw material is effectively reduced; one-pot integrated reaction is adopted in the preparation process, intermediate separation is not needed, the opportunity that metal impurities are introduced due to multiple transfer and purification operations in a traditional method is reduced, and the content of the metal impurities in the product can be reduced; distillation and other steps with high energy consumption and long time consumption are omitted, so that the reaction period is shortened, and the energy consumption is reduced.

This invention discloses a method for preparing high-purity hydroiodic acid based on an electrodialysis system, belonging to the fields of chemical engineering and new energy technology. The method includes: introducing a first iodide solution into the material chamber of a three-compartment bipolar membrane electrodialysis system; after acid-base preparation, a second iodide solution is obtained; the obtained second iodide solution is then introduced into the desalination and concentration chambers of a two-compartment homogeneous membrane electrodialysis system for electrodialysis concentration, yielding a third and fourth iodide solution; the products from each stage can be reused or sold after processing. This invention avoids the generation of the byproduct iodate, directly generating a high-purity, high-concentration hydroiodic acid solution, eliminating cumbersome and expensive purification steps, and completely achieving product separation. The process is simple, safe, and environmentally friendly. The acid produced by the three-compartment bipolar membrane electrodialysis system becomes a qualified hydroiodic acid product after passing through an MVR evaporation system, and the produced alkali, as a byproduct, can be sold or utilized, turning waste into treasure.

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.

A liquid-liquid reactor for the production of hydriodic acid and sulfur dioxide from sulfur-containing hydrocarbons or hydrogen sulfide dissolved in liquid hydrocarbon streams, iodine and water as part of a larger process for the production of hydrogen is described. Methods and equipment for the removal of sulfur from liquid hydrocarbons and the use of an iodine chemical cycle to produce hydrogen gas from the byproducts of this purification are described.

The application discloses a methyl guanidine dipeptide compound and a synthesis method and application thereof, and belongs to the technical field of chemical synthesis, and the chemical structural formula of the compound is as follows: the synthesis method of the methyl guanidine dipeptide compound comprises the following steps: L-ornithine hydrochloride and 1,2-dimethyl-2-isothiourea hydroiodide are heated and reacted overnight in an alkaline solution; the pH value of the solution is adjusted to be neutral, purification is carried out, water is added for dissolution and the solution is adjusted to be acidic, ion exchange resin is passed through, and an intermediate 1 is obtained; pure water and isopropyl alcohol are added to the intermediate 1 and adjusted to be alkaline; isovaleryl chloride is added to the solution and adjusted to be alkaline, and the solution is stirred and reacted at room temperature; the solution is kept alkaline, heated to 45-55 DEG C, adjusted to be weakly acidic, cooled to 5-15 DEG C, and the precipitate is collected, so that a crude product is prepared; the crude product is dissolved in a methanol-water mixed solution, gradient elution is carried out through liquid chromatography, and drying is carried out, so that the methyl guanidine dipeptide compound is prepared. The methyl guanidine dipeptide compound synthesized by the method has high purity, the synthesis process is simple, and the operation is convenient.

The invention relates to a synthesis method of a perovskite microcrystalline material, and belongs to the field of perovskite materials. The invention provides a synthesis method of a perovskite microcrystalline material, which comprises the following steps: mixing alkali metal iodide salt, lead acetate trihydrate and formamidine acetate, and reacting under preset conditions to obtain the formamidine lead iodide perovskite microcrystalline material. According to the method, an acid-free system is adopted for synthesizing the formamidine lead iodide perovskite microcrystal material for the first time, hydroiodic acid which is indispensable and extremely high in danger coefficient in a traditional aqueous phase method is completely abandoned, alkali metal iodide salt is creatively adopted as a green iodine source, high-quality formamidine lead iodide perovskite microcrystals are successfully synthesized, the material performance is guaranteed, and meanwhile the yield of the formamidine lead iodide perovskite microcrystals is increased. The safety of the synthesis process is greatly improved; in addition, the solid salt with stable properties is adopted, so that the sensitivity of the whole synthesis process to air and humidity is reduced, and better repeatability and stability are achieved.

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.

This invention relates to the field of alkali metal-chlorine secondary battery technology, and discloses an electrolyte additive, an electrolyte, and an alkali metal-chlorine secondary battery. The additive contains components A, B, and C in a mass ratio of 1:0.2-2.0:0.5-3.0; component A is selected from at least one of ethyl viologen dibromide, benzyl viologen diiodide, and 1,4-phenylenediamine hydroiodate; component B is selected from at least one of 3-(4-iodophenyl)-3-(trifluoromethyl)-3H-bisacrylidine, 1-bromo-2-fluorobenzene, and 4-(benzyloxy)-1-bromo-2-fluorobenzene; and component C is selected from at least one of 3-(trifluoromethyl)phenyltrimethylammonium bromide, (3-fluoro-4-iodophenyl)methylamine, and 3-iodobenzylamine. The electrolyte provided by this invention, when applied in an alkali metal-chlorine secondary battery system, exhibits high reversible capacity, cycle stability, and environmental adaptability.

The invention discloses a catalyst separation device and separation method for a process for synthesizing acetic acid by methanol carbonyl, and belongs to the technical field of acetic acid synthesis device.The catalyst separation device comprises a spray tower, a liquid preparation tank is arranged on one side of the spray tower, and the spray tower is connected with the liquid preparation tank through a high-pressure acid-resistant pump; a collecting pipe is fixedly mounted on one side of the high-pressure acid-resistant pump, a carbon monoxide tank is arranged on the other side of the spray tower, and a supplementing assembly is arranged at the top end of the liquid preparation box. By arranging the supplementing assembly, when the liquid level of a hydroiodic acid solution in the liquid preparation box descends, a floating ball automatically detects that the content of the hydroiodic acid solution in the liquid preparation box is low, so that a ball valve is driven to be opened, the hydroiodic acid solution flows into the liquid preparation box through a supplementing pipe, the negative pressure in the high-pressure acid-resistant pump is stable, output is uniform, and the stability of a catalyst is improved; the generation of a deactivated catalyst is reduced, and the separation effect in the spray tower is improved.

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 invention discloses a methylamine formamidino perovskite single crystal, a preparation method thereof and an X-ray detector, and belongs to the technical field of perovskite single crystal X-ray detectors. Methyl iodide amine, formamidino hydriodate and lead iodide are used as raw materials, anhydrous acetic acid is used as an additive, growth is carried out in a solvent through a seed crystal method, and the methylamine formamidino perovskite single crystal is obtained. Anhydrous acetic acid and formamidine generate hydrogen-bond interaction, formamidine is pulled to enter crystal lattices, so that phase separation is eliminated, acetate and Pb coordinate to delay formation of a lead-iodine framework, the speed of methylamine and formamidine entering the crystal lattices is balanced, meanwhile, the stability of a methylamine formamidine perovskite precursor solution is improved, stable growth of methylamine formamidine perovskite single crystals is achieved, and the methylamine formamidine perovskite single crystals are obtained. The single crystal has the advantages of high crystallinity, low defect density, large size and favorable X-ray response performance. The methylamine formamidine perovskite single crystal is high in controllability in the growth process, and the preparation method is high in operability, simple and easy to implement, short in preparation period, low in equipment requirement and low in cost.

This invention discloses a one-dimensional copper-iodine-based hybrid perovskite semiconductor material synthesized from imidazole, cuprous iodide, sodium phosphate, and hydroiodic acid using a solution-cooled crystallization method. The chemical formula is (C3H5N2)3CuI6. The preparation method includes the following steps: Step 1, weighing raw materials: weigh imidazole and cuprous iodide; Step 2, mixing raw materials: place imidazole and cuprous iodide in a glass bottle, add sodium phosphate and hydroiodic acid; Step 3, heating and stirring: heat and stir until dissolved; Step 4, cooling and crystallizing: place in situ and cool; Step 5, preliminary identification of the product: irradiate the crystal with an ultraviolet lamp and observe the color of the reflected light; Step 6, filtration and drying: filter and dry the crystal to obtain the product. This invention is simple and, by introducing cuprous iodide, achieves strong exciton recombination and efficient self-trapped exciton emission, exhibiting good photoelectric conversion performance, thus replacing lead-based hybrid perovskite materials to a certain extent.

The application discloses a method for continuously preparing hydriodic acid. The method comprises the following steps: dissolving phosphorous acid in oxygen-free water to obtain an aqueous phase feed liquid; dissolving elemental iodine in a water-insoluble inert organic solvent to obtain an organic phase feed liquid; continuously contacting the organic phase feed liquid with the aqueous phase feed liquid through micro-interface mass transfer to generate a reduction reaction; continuously discharging a mixed liquid obtained after the reaction; and collecting a lower aqueous phase after the mixed liquid is allowed to stand and separate into layers, and then filtering and performing vacuum rectification to obtain the hydriodic acid. The method for continuously preparing the hydriodic acid by using the water-inert organic solvent two-phase micro-interface mass transfer technology not only completely avoids the problem of excessively high local iodine concentration in the aqueous phase, reduces the generation of free iodine from the source, but also improves the inter-phase mass transfer efficiency, so that the reaction can be completely performed under low-temperature conditions, the thermal decomposition rate of the hydriodic acid is significantly reduced, and the decomposition and oxidation of the hydriodic acid are effectively inhibited.

This application discloses a shell-like layered flexible electromagnetic shielding composite film and its preparation method, belonging to the field of biomimetic composite materials. This application uses cellulose nanocrystals (CNCs) dispersion as raw material and prepares CNCs graft-modified materials through graft polymerization. Using graphene oxide, CNCs graft-modified materials, and cellulose nanofibers (CNF) as raw materials, a graphene oxide / CNCs graft-modified material / CNF composite film is prepared through evaporation-induced self-assembly. Then, it is reduced with a hydroiodic acid / short-chain fatty acid mixed solution to obtain a reduced graphene oxide / CNCs graft-modified material / CNF composite film. The graphene composite film prepared in this application exhibits good strength and toughness, good conductivity and fatigue-resistant conductive stability, and good electromagnetic shielding performance.

The application discloses a kind of coupling membrane separation and pressure swing adsorption's sulfur-iodine cycle hydrogen purification method and device.The method comprises: the decomposition product gas from hydrogen iodide decomposition unit enters preliminary treatment unit and is condensed to remove water, to realize preliminary separation;After preliminary separation, mixed gas enters membrane separation equipment, and membrane separation equipment is based on molecular size rejection mechanism to realize the preliminary separation between hydrogen and other impurities, and hydrogen in mixed gas enters the permeation side through membrane material, to form the preliminary purification hydrogen-rich gas stream;Hydrogen-rich gas stream enters PSA purification device, and PSA purification device uses gradient adsorbent bed to purify hydrogen-rich gas stream, to obtain high-purity hydrogen.The application solves the problem of low purity and low yield in sulfur-iodine cycle hydrogen purification, and provides an efficient purification scheme for sulfur-iodine cycle and other thermochemical hydrogen production technologies.

The application provides a flexible perovskite battery and a preparation method thereof, and belongs to the technical field of solar cells, and comprises the following steps: mixing thermoplastic polyurethane and 3-isocyanate propyl triethoxysilane, adding anhydrous N,N-dimethylformamide, and heating to obtain a modified polyurethane solution; mixing formamidinium hydroiodide, iodide, methylammonium salt, the modified polyurethane solution and 4-hydrazinyl benzenesulfonic acid, adding DMSO / DMF solvent, and stirring to obtain a perovskite precursor solution; taking a PET / ITO substrate as a bottom electrode layer; spin coating an isolation layer on the bottom electrode layer; spin coating a SnO2 precursor solution on the isolation layer to obtain an electron transport layer; spin coating the perovskite precursor solution on the electron transport layer to obtain a perovskite layer; spin coating a hole transport layer mixture on the perovskite layer to obtain a hole transport layer; and evaporating a top electrode layer on the hole transport layer to obtain the flexible perovskite battery. The perovskite battery prepared by the application has good flexibility and tensile properties, and the water and oxygen resistance is improved.

The invention discloses a method for improving the photoyield of a Cs3Cu2I5 scintillator through Cr < 3 + > / Mn < 2 + > co-doping. Compared with a traditional high-temperature melting method, a vacuum evaporation method, an anti-solvent method and other processes which depend on complex equipment, high temperature and high pressure or a large amount of toxic organic solvents, the method has the advantages that important innovation is achieved on the scintillator preparation process, and high efficiency, environment friendliness and excellent expandability are achieved; according to the method, a solution method cooling crystallization strategy taking a hydroiodic acid-hypophosphorous acid mixed solution as a medium is adopted, so that the process is fundamentally simplified, the reaction condition is mild, the dependence on harsh equipment and the preparation cost are remarkably reduced, meanwhile, the use of a toxic solvent is avoided, and the method has better environmental friendliness. According to the method, heating reaction is carried out at the temperature of 180-240 DEG C for only 0.5-2.0 hours, then natural cooling is carried out for 8-24 hours, a large number of evenly-crystallized Cs3Cu2I5: Cr < 3 + > and Mn < 2 + > small broken crystals can be obtained, the technological process is high in controllability and repeatability, large-scale preparation of large-area and high-quality scintillator materials is easy to achieve, and a reliable path is provided for industrial popularization.

This invention discloses a hybrid perovskite crystal for dual stimulation response by heat and guest molecules, its preparation method, and its applications. The general molecular formula of the hybrid perovskite crystal is [C9H]. 22 PO][PbI3]·H2O, with a molecular weight of 783.1, wherein C9H 22 PO + The compound is composed of (1-hydroxy)triisopropylphosphine ions. The crystal is monoclinic with chiral space group P21. The (1-hydroxy)triisopropylphosphine organic ligand is dissolved in lead iodide using hydroiodic acid solution, and yellow, blocky one-dimensional perovskite crystals are obtained by a solution cooling method. The preparation method is simple, efficient, and reproducible. The compound exhibits piezoelectricity at room temperature. After high-temperature dehydration, the compound [C9H...]... 22 PO][PbI3]·H2O transforms into [C9H 22 [PO][PbI3], the latter undergoes two reversible phase transitions and exhibits second harmonic generation (SHG) switching and dielectric switching functions.

The present invention belongs to the field of new energy and photocatalytic technology, and specifically relates to a d-PtNi / MAPbI3 photocatalyst and its preparation method and application. A platinum source, a nickel source, NaBH4, PVP and ethylenediamine are uniformly mixed and then subjected to a solvent thermal reaction to obtain a PtNi alloy. The PtNi alloy is added to hydroiodic acid for a dealloying reaction to obtain d-PtNi; d-PtNi and MAPbI3 are added to a saturated MAPbI3 solution, stirred and subjected to a photodeposition reaction to obtain a d-PtNi / MAPbI3 photocatalyst. The d-PtNi / MAPbI3 photocatalyst has excellent photogenerated carrier separation ability, effectively improving the photocatalytic hydrogen production performance and cycle stability. At the same time, the low loading of d-PtNi reduces the preparation cost.

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.

The invention relates to the technical field of organic synthesis, in particular to a method for preparing 3H-1, 2-benzodisulfonyl-3-ketone. The invention relates to a conventional synthesis method of 3, 3, 3-H-1, 2-benzodisulfonyl-3-ketone, which needs to use a thiophenol raw material with an unpleasant smell or a transition metal catalyst or a large amount of organic acid. In order to solve the technical problem, the invention provides the method for preparing the 3H-1, 2-benzobenzene-3-ketone, which comprises the following steps: by taking hydriodic acid as an additive and taking 2-methylbenzo [d] isothiazole-3 (2H)-ketone and a sodium sulfide hydrate as reaction raw materials, stirring and reacting in an organic solvent to generate the 3H-1, 2-benzene-3-ketone. In the reaction process, any thiophenol raw material or transition metal catalyst or a large amount of organic acid does not need to be added, the method is simple, raw materials are easy to obtain, and the method is green, environmentally friendly and high in yield and has good application prospects.

Disclosed are a method for synthesizing a perovskite precursor solution of a formamidine-based ionic liquid, a cell device, and a solar cell. The method includes: adding an organic sodium salt and formamidine hydrochloride to ethanol, respectively, stirring to obtain a formamidine hydrochloride solution and a sodium alkyl carboxylate solution; dropwise adding the formamidine hydrochloride solution to the sodium alkyl carboxylate solution, stirring the mixed solution; filtering the reacted mixed solution and extracting a filtrate, performing rotary evaporation to remove ethanol, and performing oscillating washing; performing secondary filtration, extracting a filtrate, and performing rotary evaporation to remove the organic solvent, to obtain an organic acid formamidine ionic liquid; and dissolving lead iodide and formamidine hydriodide into the organic acid formamidine ionic liquid for reaction to obtain the perovskite precursor solution of the formamidine-based ionic liquid. The method solves the problem of poor phase stability of FAPbI3 perovskite in humidity environments.

The invention belongs to the technical field of solar cell manufacturing, and provides a perovskite solar cell and a preparation method thereof. The perovskite solar cell comprises a conductive substrate, an electron transport layer, a perovskite layer, a passivation modification layer, a hole transport layer and an electrode layer. The perovskite layer is a perovskite layer modified by 2-aminopurine; and a passivation material in the passivation modification layer is 2-mercaptoethane-1-sulfonamide hydriodate. According to the invention, 2-aminopurine and 2-mercaptoethane-1-sulfonamide hydriodate are used for synergistically passivating the perovskite layer, so that the crystal defect and vacancy defect of the perovskite thin film are reduced, and the crystal quality of the perovskite thin film is improved, thereby improving the open-circuit voltage, short-circuit current density and energy conversion efficiency of the perovskite solar cell; and commercial application development of the perovskite solar cell is promoted.

The invention belongs to the field of organic-inorganic hybrid functional crystal materials, and relates to an inorganic-organic hybrid three-dimensional crystal as well as a preparation method and application thereof, raw materials containing hydroiodic acid, a protonated organic molecular cage C-D3T2 and a lead source are mixed with a solvent, and the inorganic-organic hybrid crystal is obtained through solvothermal reaction. The chemical formula of the prepared crystal is {[C-D3T2] [Pb5I14 (I3)]}. I. 6H2O; wherein the molecular formula of the C-D3T2 organic cage is H6 [C36H54N8]. The crystal is of a host-guest body structure assembled by a three-dimensional inorganic framework [(Pb5I14) I3] n5n-and a C-D3T2 molecular cage through electrostatic interaction and belongs to a monoclinic system, and the space group is C2 / c. The crystal is of a three-dimensional nested structure constructed by an organic molecular cage and inorganic lead iodide for the first time, and has certain application potential in the field of photothermal conversion.

The application discloses a two-dimensional hybrid perovskite nanosheet with out-of-plane ferroelectricity and a preparation method and application thereof. The preparation process of the nanosheet is as follows: raw materials including lead iodide, phenethylammonium iodide and methylammonium hydroiodide are dispersed in an organic solvent to obtain a mother liquor; a red precipitate is generated by adding a precipitating solution dropwise into the mother liquor, and supernatant is taken and placed on a lower PDMS substrate; an upper PDMS substrate is covered on the lower PDMS substrate on which the supernatant is placed, and after heat treatment and volatilization of the organic solvent, the upper and lower PDMS substrates are separated. The nanosheet has out-of-plane ferroelectric polarization and single ferroelectric domain characteristics based on organic-inorganic hybridization and a special space group structure, and has advantages of excellent structural stability and conductivity. A two-dimensional photodetector prepared by using the nanosheet can be spontaneously polarized, thereby being self-powered, and the on-off ratio of the photodetector is as high as 10 4 , and a photocurrent can reach 30 nA, thereby greatly improving the comprehensive performance of the photodetector.

The invention discloses a two-dimensional hybrid perovskite nanosheet with out-of-plane ferroelectricity as well as a preparation method and application of the two-dimensional hybrid perovskite nanosheet. The preparation process of the nanosheet comprises the following steps: dispersing raw materials including lead iodide, phenylethyl amine iodide and formamidine hydriodate into an organic solvent to obtain a mother solution; dropwise adding an eluate into the mother liquor to generate a red precipitate, taking a supernatant, and placing the supernatant on a lower PDMS substrate; and covering the upper PDMS substrate on the lower PDMS substrate on which the supernatant is placed, carrying out heat treatment, and after the organic solvent is volatilized, separating the upper PDMS substrate from the lower PDMS substrate. The nanosheet is based on organic-inorganic hybridization and a special space group structure, is endowed with out-of-plane ferroelectric polarization and single ferroelectric domain characteristics, and has the advantages of excellent structural stability, conductivity and the like. The two-dimensional photoelectric detector prepared by adopting the material can be spontaneously polarized so as to be self-powered, the switch ratio of the detector reaches up to 104, the light current can reach 30nA, and the comprehensive performance of the detector is greatly improved.

Disclosed in the present invention is a method for regulating and controlling a phase of aqueous synthetic formamidine lead iodine perovskite powder, for use in synthesizing pure α-phase and δ-phase perovskite powder. The method comprises the following steps: first dissolving a lead source in an aqueous acetic acid solution, then adding formamidine acetate, stirring to obtain a clear and transparent solution, adding hydroiodic acid to obtain a large amount of precipitate, filtering and collecting the precipitate, using a detergent to wash the precipitate, then collecting a solid product, placing the solid product in a drying oven, and drying to obtain the perovskite powder. The pure α-phase and δ-phase perovskite powder can be obtained by controlling the type of a washing solvent and a drying temperature.

A flux containing rosin, a solvent, a thixotropic agent, an amine hydroiodide, and an activator (provided that the amine hydroiodide is excluded), in which the amine hydroiodide includes a heteroalicyclic amine hydroiodide, is provided in the present invention. As the heteroalicyclic amine hydroiodide, at least one selected from the group consisting of piperidine hydroiodide and pipecholine hydroiodide is preferable. According to such flux, the generation of voids during soldering can be further suppressed.

The present application belongs to the technical field of waste lead-acid battery resource and lead iodide crystal preparation, and discloses a method for preparing lead iodide crystal by reducing lead paste through a short wet process, which comprises the following steps: S1: collecting waste lead paste from waste lead-acid batteries and reducing the waste lead paste to obtain reduced lead paste; the reduced lead paste is placed in an iodine salt solution and stirred to obtain a preliminary reaction solution; S2: adding a hydroiodic acid solution to the preliminary reaction solution, and then performing solid-liquid separation to obtain a crude crystal; S3: dissolving the crude crystal in an organic solvent, and then performing solid-liquid separation; the obtained filtrate is a lead iodide solution; S4: recrystallizing the lead iodide solution, and then performing solid-liquid separation to obtain a purified lead iodide crystal. Through the improvement of the overall design of the reaction participants and the process flow, the preparation of the lead iodide crystal can be realized through a short process, and the technical problems of long process steps, large reagent input, and low purity of the lead iodide product can be effectively solved.