429 results about "Crystallization rate" patented technology

The embodiment of the invention relates to the photovoltaic field, and provides a back contact battery and a manufacturing method thereof, and a photovoltaic module, the back contact battery comprises a substrate, the substrate is provided with a first surface and a second surface which are opposite to each other along a first direction, and the second surface is provided with first regions and second regions which are alternately arranged along a second direction; the first dielectric layer and the first doping layer are stacked on the first region, and P-type doping elements are arranged in the first doping layer; the second dielectric layer and the second doping layer are stacked on the second region, and the second doping layer is provided with N-type doping elements; wherein the first doped layer comprises N layers of stacked first doped films, the crystallization rate of the (N-1) th layer of first doped film is higher than the crystallization rate of the Nth layer of first doped film in the direction away from the substrate, and N is a positive integer greater than or equal to 2. The embodiment of the invention is at least beneficial to improving the photoelectric conversion efficiency of the back contact battery.

The invention belongs to the technical field of solar power generation, and particularly relates to a back contact BC solar cell structure and a preparation method thereof. A tunneling SiO2 layer and a phosphorus-doped N + poly layer with high crystallization rate and low parasitic absorption are arranged in a back N region of the cell; the P region is sequentially provided with an i: a-Si layer, a P: a-Si sub-layer and a P-uc-SiOxCy sub-layer; the front surface of the cell is provided with a laminated gradient silicon nitride antireflection passivation film; the back N region adopts the SiO2 layer and the N + poly field structure with high crystallization rate and low parasitic absorption to replace an i: a-Si + N: a: Si field structure of a traditional HBC to improve the current density, and the back N region adopts the suede light trapping structure to replace a polishing structure to improve the current density. A low-temperature silicon nitride antireflection film is additionally arranged on the upper layer of the TCO transparent conductive film to improve passivation and current density, silicon nitride coverage antireflection is carried out on the isolation regions of the P region and the N region to improve passivation and current density, the back efficiency of the cell is improved, and the double-sided rate is improved.

A method for separating amoxicillin and phenylacetic acid from reaction solution in one-step enzymatic synthesis of amoxicillin is provided. The method employs immobilized penicillin acylase mutant to catalyze the one-step synthesis of amoxicillin from penicillin potassium, and develops a separation process for the resulting reaction mixture. The technical scheme mainly comprises: Firstly separating the immobilized penicillin acylase mutant from the reaction solution through filtration; subsequently isolating amoxicillin via crystallization; followed by separating and recovering phenylacetic acid through toluene extraction and back extraction. This separation method enables rapid and efficient isolation of amoxicillin with high production yield, achieving an average crystallization rate of 93.22%. Concurrently, it demonstrates effective separation and recovery of phenylacetic acid while allowing recyclable use of the toluene extractant.

The invention relates to a crystallization method of ammonium metavanadate crystals. The crystallization method comprises the following steps: cooling an ammonium metavanadate concentrated solution to obtain an ammonium metavanadate supersaturated solution; the cooling treatment process comprises the step of adding a crystallization regulating agent into the ammonium metavanadate concentrated solution; sequentially carrying out aging treatment and solid-liquid separation on the ammonium metavanadate supersaturated solution to obtain an ammonium metavanadate solid phase; by adding a crystallization regulating agent in the cooling treatment process, regulating the growth rate and growth direction of ammonium metavanadate crystals, matching with the steps of aging treatment and the like, the crystallization rate of the crystallization method is improved, preferably, the crystallization rate is up to 89.5% or above, and the high-purity ammonium metavanadate product with large grain size and regular morphology is obtained. Wherein the median particle size preferably reaches up to 86.5 microns or above, the purity reaches up to 99.97% or above, and the requirement for high-quality vanadium products at present is met.

The invention relates to the field of silicon carbide crystal growth, in particular to a high-efficiency silicon carbide single crystal growth method which comprises the following steps: (S.1) providing a reverse thermal field environment of which the temperature is sequentially reduced from top to bottom in the vertical direction; (S.2) heating the silicon carbide powder so as to generate silicon carbide sublimation gas; (S.3) the silicon carbide sublimation gas is introduced into the thermal field environment along with the carrier gas, so that the silicon carbide sublimation gas is layered under screening of the carrier gas, and a silicon-rich atmosphere located at the top of the thermal field environment and a supersaturated atmosphere located at the bottom of the thermal field environment are obtained; and (S.4) contacting the supersaturated atmosphere with a seed crystal arranged at the bottom of the thermal field environment so as to grow the silicon carbide single crystal on the surface of the seed crystal. Through the reverse thermal field design, carrier gas screening layering and carbon powder dynamic compensation mechanism, the problems that in traditional silicon carbide single crystal growth, silicon gas phase enrichment inhibits the crystallization rate, and defects are caused by unbalance of the stoichiometric ratio are systematically solved.

The invention relates to a preparation method of a solar cell piece and the solar cell piece, and the preparation method of the solar cell piece comprises the following steps: preparing a tunneling oxide layer on the surface of an n-type crystalline silicon substrate, depositing polycrystalline silicon on the surface of the tunneling oxide layer under a first condition, and forming a first polycrystalline silicon layer, polycrystalline silicon is deposited on the surface of the first polycrystalline silicon layer under a second condition to form a second polycrystalline silicon layer, the temperature T1 of the first condition is larger than the temperature T2 of the second condition, the crystallization rate in the first polycrystalline silicon layer is smaller than the crystallization rate in the second polycrystalline silicon layer, annealing treatment and boron diffusion are carried out on the first polycrystalline silicon layer and the second polycrystalline silicon layer under the same condition, and the polycrystalline silicon layer is formed. The first polycrystalline silicon layer is converted into a first doped polycrystalline silicon layer, the second polycrystalline silicon layer is converted into a second doped polycrystalline silicon layer, the ratio F of the concentration of the first doped polycrystalline silicon layer to the concentration of the second doped polycrystalline silicon layer is larger than or equal to 0.01 and smaller than or equal to 0.1, the boron doping concentration in the first doped polycrystalline silicon layer in direct contact with the tunneling oxide layer is reduced, and the passivation level is improved.

The utility model discloses a hybrid passivation back contact cell. The cell comprises a silicon wafer; the heterostructure comprises a first passivation layer which is at least stacked on the first region and a first microcrystalline silicon layer which is fully or partially doped; the first electrode structure is located on the first microcrystalline silicon layer in the heterostructure; the first passivation structure comprises a tunneling oxide layer and a doped polycrystalline silicon layer which are stacked on the second region; the second electrode structure is located on the doped polycrystalline silicon layer in the first passivation structure; the second passivation structure comprises a second passivation layer at least stacked on the first surface and a second microcrystalline silicon layer which is fully or partially doped, the crystallization rate of the second microcrystalline silicon layer is larger than that of the first microcrystalline silicon layer, and the doping type of the second microcrystalline silicon layer is opposite to that of the first microcrystalline silicon layer. According to the utility model, good passivation and tunneling contact performance can be realized, and the electrical performance and the photoelectric conversion efficiency of the cell are significantly improved.

The invention belongs to the technical field of back contact cells, and particularly relates to a back contact cell with a specific passivation structure and a manufacturing method and application of the back contact cell. A second semiconductor layer in the back contact cell comprises an amorphous silicon layer and a second doped crystalline silicon layer which are sequentially arranged from the back face of a silicon wafer to the outside; the second doped crystalline silicon layer comprises a second doped microcrystalline region and second doped amorphous regions located on the two sides of the second doped microcrystalline region, the second doped microcrystalline region is located at the position corresponding to the second semiconductor opening region and makes contact with the conductive film layer, and the second doped amorphous regions are laid at the end of the side face of the first doped polycrystalline silicon layer and outside the back face of the adjacent part of the first doped polycrystalline silicon layer; wherein the crystallization rate of the second doped microcrystalline region is 5%-80%. According to the invention, the bulk resistivity of the second doped crystalline silicon layer can be greatly reduced, and the contact resistivity between the second doped crystalline silicon layer and the conductive film layer is also reduced, so that the series resistance of the cell is greatly reduced, the leakage current is effectively avoided, and the cell efficiency is improved.

The invention provides a PEF hydrogen bond reinforced modified polyester material and a preparation method thereof, and the preparation method comprises the following steps: blending 2, 5-furandicarboxylic acid and a third monomer hydroxy acid, and copolymerizing under the action of ethylene glycol to synthesize bio-based furan polyester, namely the PEF hydrogen bond reinforced modified polyester material. The introduced hydroxyl is used as a hydrogen bond donor to enhance the PEF copolyester material, so that the interaction strength and the chain stacking density between PEF chains are improved, the toughness, the melt strength and the crystallization rate of PEF can be improved by only adding a small amount of hydroxyl, and the barrier property of PEF copolyester is maintained to be more than 5 times of that of PET (Polyethylene Terephthalate).

The invention belongs to the technical field of 3D printing materials, and particularly relates to an interlayer reinforced composite material, a preparation method thereof and application of the interlayer reinforced composite material as a 3D printing material. A copolymerization group is introduced into polyaryletherketone, so that polyaryletherketone has a unique molecular structure and can compete with folding of an ether ketone chain segment in the crystallization process, in this way, in-situ copolymerization polyaryletherketone has a lower crystallization rate compared with polyether-ether-ketone or a polyether ketone system, the healing time of adjacent fused filaments of a 3D printing product is prolonged, and the 3D printing quality is improved. Compared with a conventional 3D printing material, the 3D printing material has the advantages that the interlayer strength is effectively improved and the interlayer reinforcing effect is achieved due to the long healing time, the interlayer performance of a 3D printing product obtained by using the 3D printing material is good, the tensile strength is 120-130 MPa, the interlayer tensile strength is 20-30 MPa, and the application range is wider. The interlayer reinforced composite material provided by the invention has the advantages of lower melting point, favorable processability, favorable mechanical properties, favorable high-temperature resistance and excellent comprehensive properties.

The invention belongs to the technical field of pipe manufacturing, and particularly relates to a manufacturing method of a surface-traceless water supply steel wire mesh reinforced polyethylene composite pipeline, which comprises the following steps: core layer extrusion molding, core layer vacuum cooling shaping, steel wire winding, outer layer PE raw material covering, internal pressure sizing and gradient cooling, code spraying, cutting and sealing. The gradient cooling is divided into three stages of cooling, the first stage is pre-cooling shaping and warm water spraying pre-cooling, shock cooling hardening of the surface of a melt is avoided, meanwhile, internal pressure sizing is conducted on the pipe, the pipe wall is made to be tightly attached to a sizing sleeve through internal air pressure, and concave-convex marks of the steel wire mesh composite pipe are eliminated; gradient cooling is adopted in the second stage, multi-stage water tank segmented cooling is adopted, and the temperature of each stage of water tank is adjusted; and the third stage is post-cooling treatment, low-temperature aerial fog cooling is adopted to further eliminate internal thermal stress, and the temperatures of the first stage, the second stage and the third stage are gradually reduced. The melt flow stress can be eliminated, the crystallization rate is controlled, the internal thermal stress is eliminated, and the pipe quality is ensured.

The invention relates to the technical field of photovoltaic cells, and discloses a selective passivation contact structure, a preparation method thereof and application of the selective passivation contact structure to preparation of a selective TOPCon cell. The method comprises the steps that a first tunneling oxide layer, first thin intrinsic amorphous silicon with the high crystallization rate and second thick intrinsic amorphous silicon with the low crystallization rate are sequentially prepared on the back face of a silicon wafer; boron diffusion doping is carried out, so that the first boron-doped polycrystalline silicon and the second boron-doped polycrystalline silicon have difference in doping concentration and crystallization rate; in the alkali etching process after laser patterning, first boron-doped polycrystalline silicon and a first tunneling oxide layer in a back non-electrode contact area are reserved by utilizing the etching rate difference of an alkaline solution on BSG and two layers of boron-doped polycrystalline silicon with different doping concentrations and crystallization rates; and the first tunneling oxide layer, the first boron-doped polycrystalline silicon and the second boron-doped polycrystalline silicon in the back electrode contact region are reserved. According to the method, the process steps can be simplified, parasitic absorption and recombination are reduced, passivation and transverse transmission are improved, and the cell efficiency is improved.

The utility model relates to the technical field of fluoroethylene carbonate purification, and discloses a fluoroethylene carbonate purification device which comprises a crystallization chamber, the top of the crystallization chamber is fixedly connected with a filtering connecting pipe, and the top of the filtering connecting pipe is fixedly connected with a mixing box; according to the raw material mixing device, firstly, two raw materials to be mixed are placed in the two raw material barrels, when the raw materials need to be mixed, the rotating frame is rotated until the square clamping sleeves wrap the square rotary knobs, the connecting rods are rotated to enable the square clamping sleeves at the two ends to coaxially rotate, and the square clamping sleeves and the square rotary knobs are combined, so that the raw materials are mixed; according to the present invention, the raw liquid in the two raw material barrels can be synchronously added, the adding rate can be synchronously controlled, the stirring motor drives the rotating rod to synchronously rotate during the later-stage crystallization process, the crystallization rate can be accelerated through the two stirring rods, and the crystals attached to the inner wall of the crystallization chamber can be scraped off through the two spiral scrapers so as to improve the crystallization efficiency; and manual scraping is avoided, and the working efficiency is improved.

The invention discloses a method for selectively and efficiently removing impurities in desulfurized gypsum and preparing high-quality alpha-semi-hydrated gypsum, which comprises the following steps: (1) removing organic impurities in the desulfurized gypsum by utilizing flotation, then removing soluble impurities by washing, and aerating air to oxidize calcium sulfite into calcium sulfate dihydrate while washing, then carrying out acid leaching in a hydrochloric acid solution to remove insoluble impurities, taking out and drying to obtain treated desulfurized gypsum; and (2) adding the desulfurized gypsum treated in the step (1) into a carboxylic acid aqueous solution to carry out solution crystallization reaction, adding potassium carboxylate into the carboxylic acid aqueous solution to regulate and control the crystallization rate and crystal morphology, carrying out solid-liquid separation after the reaction is finished, and washing, drying and ball-milling the solid to obtain the high-quality alpha-semi-hydrated gypsum powder. The alpha-semi-hydrated gypsum product obtained by the invention is high in purity, and the hydrated body has high absolute dry compressive and flexural strength.

The invention discloses a preparation method of a hybrid passivation back contact battery, and the preparation method comprises the following steps: providing a silicon wafer which comprises a first surface and a second surface which are oppositely arranged, and the second surface comprises a first region and a second region; a tunneling oxide layer and a doped polycrystalline silicon layer are sequentially deposited on the second surface, the doped polycrystalline silicon layer is annealed, a PSG mask is formed on the surface of the doped polycrystalline silicon layer, the annealing temperature ranges from 800 DEG C to 900 DEG C, and the annealing time ranges from 1800 s to 2200 s; and carrying out graphical film opening on the PSG mask on the first region, and removing the tunneling oxide layer and the doped polycrystalline silicon layer on the first region. By optimizing the annealing process of the doped polycrystalline silicon layer, prolonging the annealing time and reducing the annealing temperature, the crystallization rate of polycrystalline silicon can be reduced, the photoelectric conversion efficiency of the cell is remarkably improved, and meanwhile, the electrical properties such as contact resistivity and the like are also remarkably improved.

The invention discloses a PPS / LCP (polyphenylene sulfide / liquid crystal polymer) composition and a preparation method thereof. The PPS / LCP composition is prepared from the following components in parts by weight: 43-64 parts of PPS resin, 5-15 parts of LCP resin, 15-25 parts of special glass fibers, 5-10 parts of a laser sensitizer A, 1-5 parts of a laser sensitizer B, 2-5 parts of a compatilizer, 1-3 parts of a coupling agent and 0.2-0.6 part of an antioxidant. Wherein the laser sensitizer A is a functionalized multi-walled carbon nanotube, and the laser sensitizer B is any one of basic copper phosphate, copper chromite black, zinc hydroxystannate and tin oxide. The invention provides the low-dielectric PPS / LCP composition which has excellent mechanical property and flame retardant property and can be directly formed by laser, the PPS is compounded with the LCP to reduce the dielectric constant of the composition, and the polyphenylene sulfide and the liquid crystal polymer mutually complement each other, so that the toughness and crystallization rate of the PPS are improved, and the strength and rigidity of the LCP are improved, and therefore, the composition has excellent comprehensive performance. Basic copper phosphate and functionalized multi-walled carbon nanotubes are compounded to improve the laser direct formability of the PPS / LCP composition.

The invention provides a tin-based perovskite thin film, a preparation method thereof and a tin-based perovskite solar cell, and belongs to the technical field of photovoltaic materials. The preparation method comprises the following steps: dissolving a tin-based perovskite raw material in an organic solvent, and adding polyvinyl alcohol or polyvinylpyrrolidone to prepare a tin-based perovskite precursor solution; and coating the tin-based perovskite precursor solution through a printing method to form a film, and carrying out annealing treatment to obtain the tin-based perovskite thin film. According to the invention, polyvinyl alcohol or polyvinylpyrrolidone is used to slow down the crystallization rate of perovskite, and is used as a template to provide heterogeneous nucleation sites, so that the defect state density is reduced, and the compactness of the perovskite film is improved.

A method of manufacturing an electrode for use in battery manufacturing includes drying an electrode material in a compact phase, applying an electric field to the electrode material during the compact phase, and adjusting a frequency and strength of the electric field to control crystallization of a binder material. The electrode material includes a binder material. The crystallization rate of the binder material is increased or decreased.

The present disclosure provides a method of controlling binder crystallization during a drying process in electrode fabrication. A method of producing an electrode for battery fabrication includes: drying an electrode material in a compaction phase; applying an electric field to the electrode material during the compaction phase; and adjusting the frequency and magnitude of the electric field to control crystallization of the binder material. The electrode material includes a binder material. The crystallization rate of the binder material is increased or decreased.

The utility model provides a brine evaporative crystallization device for industrial salt production, which comprises a box body, foot stools which are uniformly distributed are fixedly connected to the bottom wall of the box body, a ventilation bin is fixedly connected to the top wall of the box body, and the brine evaporative crystallization device further comprises a bearing assembly which is rotatably connected to the inner wall of the box body and is used for bearing brine to be evaporated, the bearing assembly comprises rotating frames rotationally connected to the inner wall of the box body and symmetrically distributed about the central axis of the box body, an evaporation disc rotationally connected to the inner wall of the box body through the rotating frames, and an adapter fixedly connected to the bottom wall of the evaporation disc; the supporting assembly is rotationally connected to the inner wall of the box body; the heating assembly is fixedly connected to the bottom wall of the evaporation disc; the ventilation assembly is arranged on the inner wall of the ventilation bin; the collecting assembly is arranged on the inner wall of the box body. The brine evaporation device can control the air velocity on the surface of brine in the brine evaporation process, accelerates the evaporation and crystallization rate, can automatically collect crystals evaporated from the brine, reduces the labor intensity of workers, and improves the collection efficiency of the crystals.

The present invention discloses a preparation method of high-purity amino gallium, indium, and aluminum compounds, belonging to the technical field of semiconductor chips, and comprising the following steps: The first step is to prepare a lithium dimethylamide n-hexane suspension; the second step is to prepare one of crude tris(dimethylamino)gallium dimer, crude tris(dimethylamino)indium dimer, and crude tris(dimethylamino)aluminum dimer; the third step is to purify the crude tris(dimethylamino)metal compound by stepwise cooling recrystallization to obtain high-purity amino gallium, indium, and aluminum compounds; the present invention purifies the crude tris(dimethylamino)metal compound by stepwise cooling recrystallization, which not only has high efficiency and simple process, but also has a moderate crystallization rate of the product during the recrystallization process, will not form impurity encapsulation, has good crystal form of the product, and the purity is ≥99.9999% (6N), meeting the purity requirements for ALD / CVD film deposition of semiconductor chips.

The invention provides a production device and process for increasing the content of magnesium citrate crystals. The problems that in the prior art, the impurity co-crystallization rate is high, and crystal forms are difficult to control are solved. The device comprises a gradient temperature control multi-stage crystallization device and a crystal form directional regulation and self-adaptive separation system. The gradient temperature control multi-stage crystallization device is composed of a main crystallizer, a gradient temperature control system, an ultrasonic-assisted system and a liquid phase partition circulating system, and the crystallization environment is accurately controlled through the temperature gradients of five independent temperature zones. The crystal form directional regulation and self-adaptive separation system is composed of a seed crystal dynamic inoculation device, an electric field auxiliary directional crystallization system, a real-time crystal morphology analysis system and a self-adaptive separation system, and the crystal morphology and particle size distribution can be accurately controlled. According to the process disclosed by the invention, the main content of magnesium citrate is increased to 98.8 + / -0.3%, heavy metal impurities and organic impurities are respectively reduced by 70% and 75%, the crystal form consistency is increased to 96 + / -2%, the production period is shortened by 33%, and the process has remarkable economic benefits and social benefits.

The present invention provides a novel crystal seed suitable for a crystallization fluidized bed, a preparation method thereof, and an application thereof. The performance and function of the crystal seed are optimized and improved, the crystallization rate is accelerated, the crystallization speed is shortened, and the crystal nuclei can be effectively fixed on the surface of the crystal seed during the hardness removal process, thereby avoiding the formation of microcrystalline nuclei in the water body, reducing scaling, and accelerating the start-up speed of crystallization. In addition, the preparation method of the novel crystal seed is simple and the performance is stable. According to tests, when the novel crystal seed prepared by the present invention is put into a crystallization fluidized bed reactor for a hardness removal process, the hardness removal rate can reach 85%-95%.

The invention provides a high-flowability reclaimed material modified PET injection molding material and a molding method thereof. Comprising the following steps: mixing the following components in percentage by weight: 65%-70% of recycled PET, 8%-12% of a PET-BA block copolymer, 2%-4% of a bifunctional polar chain extender, 1%-3% of a nitrogen-doped MXene nanosheet, 3%-6% of a thermally induced reversible Diels-Alder structural monomer, 8%-12% of a plasma modified POE-g-COOH toughening agent, 2%-4% of a polyester-amino silane grafted elastomer and 1%-3% of an efficient phosphate metal salt nucleating agent, by adding the PET-BA block copolymer, the nitrogen-doped MXene nanosheet and the Diels-Alder structural monomer, the melt viscosity of the material is remarkably reduced, the fluidity is improved, and the resistance in the injection molding process is reduced; according to the present invention, the difunctional polar chain extender and the plasma modified POE-g-COOH toughening agent are adopted to enhance the tensile strength, the impact toughness and the bending modulus of the recovered PET so as to make the material meet various molding requirements, and the nitrogen-doped MXene nanosheet and the efficient phosphate metal salt nucleating agent are added to improve the thermal conductivity and the crystallization rate of the material.

The invention discloses a one-way moisture-conducting biodegradable non-woven fabric and a preparation method thereof. A hydrazide compound is grafted to lignin through an acylation reaction, the lignin nanoparticle nucleating agent is prepared through a nano precipitation method, the crystallization behavior of biodegradable resin is changed through lignin nanoparticles, the crystallization rate is increased, the cooling forming period is shortened, and therefore the spinnability of the biodegradable resin is improved. Furthermore, the surface of the biodegradable non-woven fabric is subjected to hydrophilic and hydrophobic modification through a low-temperature plasma technology, and the biodegradable non-woven fabric with the one-way moisture guiding function is prepared. The problem that biodegradable plastics such as PBAT and PBS are poor in spinnability is solved, the bio-based nucleating agent is prepared to replace a traditional small-molecule organic nucleating agent, the problems that the traditional organic nucleating agent is difficult to biodegrade and easy to separate out are solved, and the prepared one-way moisture-conducting biodegradable non-woven fabric has good directional infusion performance and is suitable for being used as a non-woven fabric. The fabric can be widely applied to the fields such as sanitary napkins, paper diapers, masks and shoes.

The invention belongs to the technical field of tungsten hydrometallurgy, and particularly relates to a method for improving the crystallization rate of ammonium paratungstate, which comprises the following steps: S1, obtaining an ammonium tungstate solution which comprises metatungstate ions; s2, adding a supersaturation degree regulator into the ammonium tungstate solution, wherein the supersaturation degree regulator comprises hydrogen peroxide and ammonia water; s3, heating the ammonium tungstate solution to a first temperature, and then adding superfine ammonium paratungstate; s4, the ammonium tungstate solution is heated to a second temperature, heat preservation and continuous stirring are conducted, and ammonium paratungstate crystals are obtained; by adjusting parameters such as temperature, pH value, solvent type and concentration, optimizing crystallization conditions with metatungstate ions and ammonium paratungstate at the same time, improving the crystallization rate, and by controlling the degree of supersaturation of the solution, the situation that the crystallization rate is affected due to non-uniform crystal growth caused by too high crystallization rate is avoided, and the quality of the product is improved. The supersaturation degree can be controlled by adjusting parameters such as solution concentration and temperature.

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

The invention relates to the field of electrode materials of capacitive deionization desalination systems, in particular to low-temperature synthesis of AlFe [Fe (CN) 6] 2 and application of the AlFe [Fe (CN) 6] 2 to capacitive deionization desalination. FeCl3. 6H2O and Al (NO3) 3.9 H2O are added into deionized cold water containing C6H5Na3O7. 2H2O to be evenly stirred to obtain a solution A, and K3Fe (CN) 6 is added into deionized cold water to be evenly stirred to obtain a solution B; mixing the solution A with the solution B, aging, centrifuging and washing in a low-temperature environment, and drying to obtain AlFe [Fe (CN) 6] 2. The crystallization rate of the Prussian blue analogue is slowed down by reducing the aging temperature, so that the vacancy defect of [Fe (CN) 6] < 3-> is reduced, the structure is enhanced by introducing an inert element Al, and the prepared electrode material has high Na < + > storage capacity and excellent cycling stability and shows huge application potential in capacitive deionization desalination.

The invention provides a crystal pulling method for reducing the head resistivity of a heavily arsenic-doped silicon single crystal, and belongs to the technical field of doped silicon single crystal production. Comprising the following steps: S1, sequentially carrying out a primary doping process, a primary temperature testing process, a primary seeding process, a re-melting process, a supplementary doping process, a secondary temperature testing process, a secondary seeding process, a shouldering process and an equal-diameter process; s2, if NG appears in the guiding and releasing process or the equal-diameter process, re-melting the crystal bar and carrying out supplementary doping, and then sequentially carrying out a temperature testing process, a crystal guiding process, a shouldering process and an equal-diameter process; s3, when the sum of the first doping multiple and the supplementary doping multiple reaches the total doping multiple, supplementary doping is stopped. By controlling the doping interval time and the total doping multiple, the head resistivity can be reduced and controlled within the upper limit of the specification, and impurities can be doped more uniformly, so that the crystallization rate is increased, the drawing and discharging times are reduced, and the quality of the drawn monocrystalline silicon is ensured.

The invention discloses a perovskite solar cell based on a tin-based perovskite thin film and a preparation method of the perovskite solar cell, and belongs to the field of photoelectric materials and devices. A hole transport layer is spin-coated and deposited on conductive glass, a two-dimensional perovskite single crystal is added into a tin-based perovskite precursor solution, a tin-based perovskite thin film is prepared by using an anti-solvent method, and the tin-based perovskite thin film is obtained after annealing treatment. By adding the two-dimensional perovskite single crystal molecules, the phase distribution of the thin film can be adjusted, the crystallization rate can be reduced, the non-radiative recombination can be reduced, and the extraction and transmission of interface carriers can be promoted. Spin-coating an interface modification layer; carrying out vacuum thermal evaporation on an electron transport layer material on the interface modification layer; and sequentially carrying out thermal evaporation on a hole barrier layer and a metal electrode on the electron transport layer material to obtain the perovskite solar cell. The tin-based perovskite solar cell prepared by the invention has excellent photoelectric conversion efficiency and excellent device stability, and is beneficial to promoting the development and application of the tin-based perovskite solar cell.