35 results about "Iron phosphide" patented technology

The invention relates to a carbon-coated lithium iron phosphate material and a preparation method thereof, a positive plate and a battery. The carbon-coated lithium iron phosphate material comprises a lithium iron phosphate matrix and a carbon coating layer at least partially coating the lithium iron phosphate matrix, and the carbon coating layer comprises a carbon material doped with a silicon element and a boron element. According to the carbon-coated lithium iron phosphate material, the surface of the lithium iron phosphate matrix is coated with the carbon coating layer, and the carbon material in the carbon coating layer is doped with the silicon element and the boron element, so that the electronic conductivity of the lithium iron phosphate material can be improved; in addition, doping sources of the silicon element and the boron element can react with magnetic substances such as iron phosphide in the coating process to be converted into non-magnetic inert substances, then the content of magnetic foreign matter impurities in the carbon-coated lithium iron phosphate material is reduced, the overcharge problem is solved, the carbon-coated lithium iron phosphate material has good overcharge prevention performance, and the safety performance is improved.

The invention belongs to the technical field of battery materials, and particularly relates to a method for determining iron phosphide in a phosphate positive electrode material, the positive electrode material and application. Comprising the following steps: preparing standard solutions of a series of phosphate positive electrode materials with different iron phosphide contents; respectively collecting and purifying magnetic substances in the standard solutions, and adding a quimocilidone reagent to determine the corresponding quinoline phosphomolybdate precipitate; drawing a standard curve according to the mass of the iron phosphide and the mass of the quinoline phosphomolybdate precipitate in the standard solutions with different iron phosphide contents; preparing a to-be-detected solution, collecting and purifying magnetic substances in the to-be-detected solution, adding a quinmolybdenum citronone reagent to determine the mass of the quinoline phosphomolybdate precipitate, and calculating the content of iron phosphide in the to-be-detected phosphate positive electrode material. By means of the method, the content of trace iron phosphide in the phosphate positive electrode material can be efficiently, accurately and quantitatively analyzed, the content of iron phosphide in the phosphate positive electrode material can be quantitatively regulated and reduced, and the electrochemical performance of the phosphate positive electrode material is improved.

A catalytic electrode includes a nickel-based porous base material, and a plurality of catalytic alloy balls of nickel and another metal doped with elements, in which the another metal includes iron, the elements include C, F, and S, and the catalytic alloy balls are dispersed on the surface of the nickel-based porous base material. The catalytic electrode also includes a plurality of metal phosphide particles covering the nickel-based porous base material and the catalytic alloy balls, and the metal phosphide particle includes nickel phosphide, nickel iron phosphide, nickel cobalt phosphide, nickel copper phosphide, or nickel zinc phosphide.

The application discloses a kind of foam nickel load iron nickel bimetallic phosphide heterojunction catalyst and its preparation method and application, belong to electrocatalytic material technical field.The application is in situ grown by hydrothermal deposition in combination with low-temperature phosphorization process, and is prepared on foam nickel base Phosphide iron / Phosphide nickel heterojunction catalyst (Fe2P / Ni2P@NF).The prepared catalyst shows excellent performance in the electrocatalytic reduction of nitrate synthesis ammonia and high nitrate wastewater degradation.The preparation process of the catalyst of the application is simple, low in cost, and little to environmental pollution, and the self-supporting electrode prepared by integration can be directly applied to proton exchange membrane electrolytic cell, and has wide application prospect.

The invention relates to a positive active material, a preparation method thereof and a battery, and belongs to the technical field of batteries. V ions in the lithium ferrovanadium phosphate active material enter LFP crystal lattices through doping to replace Fe < 2 + > sites to form lattice defects, and in order to maintain electric neutrality, the system spontaneously generates additional free electrons, so that the electronic conductivity is increased, and the rate performance of the lithium ferrovanadium phosphate active material applied to a battery is facilitated. And meanwhile, on the basis of doping the V element, the mass content of iron phosphide in the lithium ferrovanadium phosphate active material is controlled to be less than or equal to 800ppb, so that the probability of side reaction with an electrolyte when the lithium ferrovanadium phosphate active material is applied to a battery can be reduced, and the cycle performance is facilitated. And the lithium iron vanadium phosphate active material has two particles with specific volume median particle sizes, so that a relatively good particle size grading relationship can be formed, the lithium iron vanadium phosphate active material has relatively high compaction density, and the volume energy density of the lithium iron vanadium phosphate active material when the lithium iron vanadium phosphate active material is applied to a battery is facilitated.

The present invention provides: a hydrogenation catalyst which can be used in a hydrogenation reaction of a cyclic aldehyde; and a method for producing an alcohol compound by hydrogenation of a cyclic aldehyde using the hydrogenation catalyst. The present invention pertains to a catalyst for hydrogenation of a cyclic aldehyde, the catalyst containing iron phosphide nanoparticles. It is preferable that the iron phosphide nanoparticles are rod-shaped particles and the maximum length of the rod-shaped particles in the major axis direction is less than 100 nm. It is preferable that the catalyst for hydrogenation of a cyclic aldehyde is a catalyst for hydrogenation of a furfural derivative.

The present invention provides a cathode active material comprising primary particles which include at least one transition metal and further comprise an iron phosphide compound, and thus exhibiting excellent charge / discharge capacity and rate performance on the basis of excellent electronic conductivity.

The invention belongs to the technical field of acyclic compounds, and particularly relates to a preparation method of tert-amyl peroxyacetate. Adding a tert-amyl hydrogen peroxide aqueous solution into a solvent, and stirring to obtain a mixed solution; under the stirring condition, p-toluenesulfonic acid and iron phosphide are sequentially added into the mixed solution, stirring reaction continues after adding is completed, and reaction liquid I is obtained; under the stirring condition, acetic anhydride is added into the reaction liquid I, stirring reaction continues after adding is completed, and reaction liquid II is obtained; adding a washing liquid into the reaction liquid II, stirring, washing, and separating to obtain a tert-amyl peroxyacetate crude product; and washing and drying the tert-amyl peroxyacetate crude product, and removing the solvent to obtain the tert-amyl peroxyacetate. The method avoids the problems of a large amount of hydrochloric acid generated by a traditional acyl chloride method and corrosivity caused by using sulfuric acid as a catalyst; meanwhile, iron phosphide has magnetism, cyclic utilization can be achieved through magnetic separation after the reaction is finished, p-toluenesulfonic acid can be regenerated through ion exchange resin, and the production cost is greatly reduced.

This application provides a lithium iron phosphate cathode material, its preparation method, a cathode sheet, and a secondary battery, relating to the field of secondary battery technology. The preparation method of the lithium iron phosphate cathode material includes the following steps: mixing lithium iron phosphate material containing iron phosphide, an oxidizing lithium source, a phosphorus source, an oxidant, water-soluble organic titanium, and a carbon source to obtain a mixture; mixing the mixture with an aqueous phase and subjecting it to gelatinization treatment to obtain a slurry; and sequentially subjecting the slurry to drying and sintering treatments to obtain the lithium iron phosphate cathode material. The technical solution of this application aims to solve the technical problem that the high iron phosphide content in lithium iron phosphate materials makes it difficult to simultaneously achieve good capacity and charge-discharge performance.

The application provides a composite lithium negative electrode material for a solid-state lithium metal battery and a preparation method and application thereof, the preparation raw material of the composite lithium negative electrode material comprises an additive, lithium metal and a solid-state electrolyte; the additive is selected from one or more of gallium phosphide, indium phosphide, tin phosphide, iron phosphide, cobalt phosphide, nickel phosphide, molybdenum phosphide, manganese phosphide, black phosphorus and red phosphorus. The composite lithium negative electrode material prepared by using the additive has good wettability to the solid-state electrolyte sheet, significantly reduces the interface resistance between the solid-state electrolyte and the lithium metal negative electrode, improves the critical current density and the cycle stability, is very close to the solid-state electrolyte sheet at the interface, has good matching with a commercial lithium iron phosphate positive electrode, and the assembled full battery has excellent rate performance and cycle performance.

The invention relates to the field of new energy materials, and particularly provides a biomass-derived carbon-supported iron phosphide nano-catalyst and a preparation method and application thereof.The biomass-derived carbon-supported iron phosphide nano-catalyst is prepared by taking waste biomass as a raw material and sodium hypophosphite as a phosphorus source through high-temperature carbonization and activation treatment to obtain a biochar carrier with a high specific surface area and a porous structure; the method is used for loading iron phosphide so as to improve the stability and the conductivity, a traditional high-energy-consumption and high-pollution ammonia synthesis process is replaced with an electro-catalysis technology, and a new way is provided for achieving green and efficient synthesis of ammonia. The invention not only helps to solve the problems of energy and environment, but also opens up a new direction for resource utilization of agricultural wastes.

This invention belongs to the field of acyclic compound technology, specifically relating to a method for preparing tert-amyl peroxide. A tert-amyl hydrogen peroxide aqueous solution is added to a solvent and stirred to obtain a mixed solution. Under stirring conditions, p-toluenesulfonic acid and ferric phosphide are added sequentially to the mixed solution. After the addition is complete, stirring continues to produce reaction solution I. Under stirring conditions, acetic anhydride is added to reaction solution I. After the addition is complete, stirring continues to produce reaction solution II. A washing solution is added to reaction solution II, and the mixture is stirred and washed, then separated to obtain crude tert-amyl peroxide. The crude tert-amyl peroxide is washed, dried, and the solvent is removed to obtain tert-amyl peroxide. This invention avoids the problems of large amounts of hydrochloric acid produced by traditional acyl chloride methods and the corrosiveness caused by using sulfuric acid as a catalyst. Furthermore, ferric phosphide is magnetic, allowing for recycling through magnetic separation after the reaction. p-Toluenesulfonic acid can be regenerated through ion exchange resin, significantly reducing production costs.

This application belongs to the field of electrocatalysis and photoelectrocatalysis materials technology, specifically relating to a nickel phosphide-iron phosphide self-supporting electrode, its preparation method, and its application. This application provides a method for preparing a nickel phosphide-iron phosphide self-supporting electrode, which directly constructs an active layer on a conductive nickel foam substrate through in-situ hydrothermal growth combined with a gas-phase phosphating strategy. The nickel foam not only acts as a conductive current collector but also participates in the growth of the precursor as a reaction substrate, enhancing the bonding force between the active layer and the substrate, completely avoiding the use of binders, and effectively reducing interfacial resistance. The phosphating treatment transforms the nickel-iron precursor into a phosphide with metal-like properties, significantly improving the electrode's conductivity and intrinsic catalytic activity, thereby solving the problem of slow reaction kinetics.

This invention discloses a method for preparing high-compact lithium iron phosphate (LFP) cathode material and the prepared LFP cathode material. Using lithium, iron, phosphorus, and carbon sources as raw materials, the LFP cathode material is prepared via a high-temperature solid-state method. A flux is added to the raw materials, and the flux is selected from one or more of magnesium carbonate, magnesium iodide, and magnesium hydroxide. This invention uses magnesium-containing compounds such as magnesium carbonate, magnesium iodide, and magnesium hydroxide as fluxes, enabling the preparation of LFP cathode material under low-temperature sintering conditions. This significantly reduces energy consumption, effectively avoids the generation of magnetic foreign matter such as iron phosphate, reduces electron transport resistance, and promotes particle densification growth. The compacted density of the prepared LFP cathode material is not less than 2.467 g / cm³. 3 The resistivity is not higher than 32.5 Ω•cm.

This invention discloses a lithium iron phosphate and its preparation method. The preparation process uses a conventional carbon source, polyethylene glycol (PEG), and an organic compound containing sulfonic acid groups as a composite carbon source. PEG promotes the uniformity of raw material mixing and carbon coating. SO3, generated from the decomposition of sulfonic acid groups, has a certain oxidizing property and counteracts the reducing atmosphere on the surface of lithium iron phosphate particles, inhibiting the excessive reduction of lithium iron phosphate to iron phosphide. The pyrolysis and carbonization of PEG and the sulfonic acid-containing organic compound compensate for the uneven coating problem of conventional carbon sources, forming a uniform conductive carbon layer on the surface. This significantly improves the electronic conductivity of the finished lithium iron phosphate cathode material, suppresses electrolyte side reactions, and thus improves initial efficiency and rate performance. The sulfonic acid compounds have high chemical stability, ensuring that more sulfonic acid compounds decompose during the high-temperature calcination stage, thereby ensuring the thoroughness and effectiveness of inhibiting the excessive reduction of lithium iron phosphate to iron phosphide.

The invention discloses a method and system for preparing iron phosphate based on continuous acidolysis of iron phosphide powder, and belongs to the technical field of wet metallurgy and battery material preparation. The method comprises the steps that a first oxidizing agent is added into reaction slurry containing a ferrous ion solution, acid and phosphating iron powder, so that Fe < 2 + > in the reaction slurry is oxidized into Fe < 3 + >, the Fe < 3 + > and iron phosphide are subjected to a redox reaction, and leachate rich in Fe < 2 + > and PO4 < 3-> is obtained; and at least part of the leachate reacts with a second oxidizing agent, so that Fe < 2 + > in the leachate is completely oxidized into Fe < 3 + >, and the Fe < 3 + > and PO4 < 3-> generate iron phosphate. According to the method, efficient and continuous dissolution of iron phosphide is achieved by constructing an ingenious iron ion internal circulation oxidation system, and the technical problem that in the prior art, direct acid dissolution of iron phosphide powder is difficult is solved; the method is short in process, low in cost and easy for industrial continuous production. The corresponding system is easy to set, simple in structure and suitable for industrial production.

This application relates to the field of materials testing technology and provides a separation and detection method suitable for the separation and detection of metallic magnetic foreign matter in lithium iron phosphate. The method includes the following steps: obtaining a primary concentrate from lithium iron phosphate slurry using a magnetic rod; placing the primary concentrate in an aqueous solution containing a viscous dispersant, using a magnet to attract and move it, separating the strongly magnetic metallic foreign matter; performing microscopic observation on the weakly magnetic impurities discharged after separation to distinguish the strongly magnetic metallic foreign matter from iron phosphide; and performing digestion treatment on the strongly magnetic metallic foreign matter and performing elemental quantitative analysis. This application achieves efficient separation of strongly magnetic metallic foreign matter from iron phosphide through a three-stage treatment method of primary screening, viscous dispersant separation, and digestion treatment, thereby improving the accuracy of the detection results. Microscopic observation further verifies and ensures the separation effect of strongly magnetic metallic foreign matter from the weakly magnetic impurity iron phosphide, thus contributing to the accuracy of the detection results.

The application provides a composite manganese iron lithium phosphate positive electrode material and a preparation method and application thereof. The composite manganese iron lithium phosphate positive electrode material comprises a lithium iron phosphate core and a successively laminated iron phosphide intermediate layer and a composite coating layer on the surface of the lithium iron phosphate core. The composite coating layer comprises a carbon material coated manganese iron lithium phosphate material. The composite manganese iron lithium phosphate positive electrode material has a core-shell structure, the core is a phosphoric acid iron coated lithium iron phosphate, and the shell layer is a carbon coated manganese iron lithium phosphate coating layer. The unique structure design of the lithium iron phosphate core and the manganese iron lithium phosphate shell layer enables the composite material to have excellent electrochemical performance.

This invention belongs to the field of energy catalysis technology and provides a black phosphorus-ferric tetraphosphide composite nanocatalyst, which is a nano-binary composite structure formed by pebble-shaped ferric tetraphosphide nanocrystals encapsulated by black phosphorus crystals. This invention uses a one-step ball milling synthesis process, under appropriate process conditions, to directly convert red phosphorus powder and iron powder into nanoparticles with a black phosphorus-ferric tetraphosphide composite composition. After simple washing and dispersion, the active sites distributed on the surface are further exposed. Characterization tests revealed a large number of nanoscale black phosphorus-ferric tetraphosphide two-phase structures in the catalyst. Electrocatalytic experiments verified that this novel material exhibits excellent activity in the electrocatalytic synthesis of ammonia.

This invention provides a modified iron phosphate material, its preparation method, and its applications. The modified iron phosphate material has a core-shell structure, with a nitrogen-doped iron phosphate core and an iron phosphide coating layer on the outer shell. The modified iron phosphate material has a three-dimensional petal-like structure. This three-dimensional petal-like structure provides ample mass transfer channels for lithium ion storage and migration, shortening the lithium ion diffusion path. Simultaneously, this structure increases the contact area between the electrode material and the electrolyte, promoting the lithiation / delithiation process. Nitrogen doping effectively adjusts the electronic structure of the iron phosphate material, thereby improving its conductivity. The iron phosphide coating layer has excellent conductivity, reducing the amorphous carbon content of the cathode material, thus increasing the compaction density of the cathode material. Furthermore, this coating layer can alleviate the volume expansion of the cathode material during charge and discharge processes. Together with the three-dimensional petal-like structure, it can enhance the overall electrochemical performance of the cathode material.

A catalyst electrode and a method of forming the same and an electrolysis device are disclosed. The catalyst electrode includes a nickel-based porous substrate; a plurality of catalyst alloy spheres of nickel and other metals, doped with a plurality of elements, the other metals including iron, and the elements including C, F, and S, and the catalyst alloy spheres being dispersed on a surface of the nickel-based porous substrate; and a plurality of metal phosphide particles coated on the nickel-based porous substrate and the catalyst alloy spheres, and the metal phosphide particles including nickel phosphide, nickel iron phosphide, nickel cobalt phosphide, nickel copper phosphide, or nickel zinc phosphide.

The application discloses a lithium iron phosphate positive electrode material and a preparation method and application thereof. The lithium iron phosphate positive electrode material comprises lithium iron phosphate particles, a doped element, an iron phosphide layer, a carbon layer and a coating layer. The doped element is doped in the lithium iron phosphate particles. The iron phosphide layer is coated on at least part of the surface of the lithium iron phosphate particles. The carbon layer is coated on at least part of the surface of the phosphide layer. The coating layer is coated on at least part of the surface of the carbon layer. The valence of the doped element is greater than +3. The application can promote the generation of the iron phosphide layer, effectively improve the intrinsic electron and ion conductivity of the lithium iron phosphate, and widen the lithium ion transmission channel and improve the material rate performance by doping the high-valence element. The coating layer is beneficial to inhibiting the continuous growth of the material, and the obtained material has good uniformity and dispersity.

The application discloses a preparation method of a ferrophosphor / nickel hollow sodium citrate carbon composite material, which comprises the following steps: solid block sodium citrate carbon preparation, ultrathin hollow sodium citrate carbon preparation, ferrophosphor / nickel hollow sodium citrate carbon precursor material preparation and ferrophosphor / nickel hollow sodium citrate carbon composite material preparation. The ultrathin hollow sodium citrate carbon is prepared and used as a hollow buffer material, so that the ferrophosphor / nickel particles can be better encapsulated, the volume expansion problem of the ferrophosphor / nickel particles in the circulation process is effectively relieved, and the stability of the material in the circulation process can be effectively improved. On the other hand, the phosphide metal contributes a high capacity to the whole material, and cooperates with the carbon shell, so that the ferrophosphor / nickel hollow sodium citrate carbon composite material has more excellent electrochemical performance in a lithium ion battery.

The invention discloses a silicon-doped nano-porous iron phosphide catalyst and a preparation method and application thereof.The preparation method comprises the steps that under the argon protective atmosphere, Fe, Fe2P and Si are smelted and cooled, and a Fe < 80-x > P20Six alloy ingot is obtained; after the Fe < 80-x > P20Six alloy ingot is smelted again, the Fe < 80-x > P20Six alloy ingot is subjected to striping treatment, and a Fe < 80-x > P20Six precursor strip is obtained; and carrying out electrochemical dealloying treatment on the Fe (80-x) P20Six precursor strip, and selectively dissolving the Fe phase to obtain the silicon-doped nano-porous iron phosphide catalyst. The silicon-doped nano-porous iron phosphide catalyst obtained by an electrochemical dealloying method has a continuous three-dimensional porous skeleton, so that the electrochemical specific surface area can be greatly increased, more catalytic active sites can be exposed, and meanwhile, the ion transmission efficiency can be improved. And the multistage pore channels are beneficial to rapid diffusion of reactants and timely desorption of products, so that the interface reaction resistance is effectively reduced, and the catalytic reaction rate and the current response are enhanced.

The invention relates to a method for preparing high-yield black phosphorus by using a P-Fe-Sn alloy catalyst based on ferrophosphorus slag, which comprises the following steps: carrying out pickling soaking, reduction heat treatment and purification on ferrophosphorus slag to obtain a Fe-P intermediate, and carrying out melt alloying on the Fe-P intermediate and elemental tin according to a reasonable ratio to obtain the P-Fe-Sn alloy catalyst; red phosphorus is used as a phosphorus source, and under the action of the catalyst, reaction is carried out for 6-24 hours at 400-600 DEG C in an inert atmosphere through a gas-phase transmission method, so that oriented growth of black phosphorus is realized. The phosphorus iron slag is used as a raw material to prepare the efficient catalyst, the phosphorus iron slag is converted into a P-Fe-Sn alloy catalyst with higher value by utilizing the unique chemical thermal stability of iron phosphide and combining with the characteristic of preparing black phosphorus through catalysis of Sn, and the use proportion of the catalyst Sn is reduced; the prepared P-Fe-Sn alloy catalyst has excellent catalytic activity, and high-yield synthesis of black phosphorus can be realized. The black phosphorus prepared by the method is good in quality, high in crystallinity and low in equipment requirement, is suitable for large-scale production, and can provide technical support for industrial application of the black phosphorus.

The invention discloses a lithium iron phosphate-based positive electrode material and a preparation method and application thereof, and belongs to the technical field of new energy. The lithium iron phosphate-based positive electrode material provided by the invention comprises lithium iron phosphate and iron phosphide distributed in the lithium iron phosphate in a penetrating manner, the mass percent of the iron phosphide in the positive electrode material is W%; in an XRD pattern of the positive electrode material, a characteristic peak exists at a diffraction angle 2theta of 40.3 + / -0.1 degrees, and the half-peak width of the characteristic peak is y degrees; and 9y + 0.06 > = W > = 8y-0.2, 0 < W < = 3, and 0 < y < = 0.4. The lithium iron phosphate-based positive electrode material provided by the invention has excellent compaction density, capacity and rate / power performance. The invention also provides a preparation method and application of the lithium iron phosphate-based positive electrode material.

The invention discloses a preparation method of a low-iron-phosphide high-compaction-density lithium iron phosphate material, which comprises the following steps: preparing a mixture containing a lithium source, a carbon source, anhydrous iron phosphate, a titanium source and a phosphorus source, and sanding to prepare mixed slurry; carrying out spray granulation on the mixed slurry to obtain an iron-lithium spray material; sintering the spray material in an inert atmosphere, crushing and screening to obtain lithium iron phosphate A; adding at least one of ammonium metavanadate and lithium ferrite into the obtained lithium iron phosphate A, adding a carbon source, uniformly mixing, and sintering in an inert atmosphere to obtain lithium iron phosphate B; and crushing the lithium iron phosphate B to obtain the lithium iron phosphate material with low iron phosphide and high compaction density. According to the invention, ammonium metavanadate and / or lithium ferrite are / is added to react with iron phosphide, so that the content of iron phosphide is effectively reduced; the compaction of the obtained material can reach 2.6 g / cm < 3 >; the cycle performance is excellent, and the 1C 100-cycle cycle retention rate is 98%.

The present invention provides a deoxygenation catalyst that can be used in a deoxygenation reaction of a sulfoxide compound, and a method for producing a sulfide compound by deoxygenation of a sulfoxide compound using the same. The present invention relates to a deoxygenation catalyst that includes iron phosphide nanoparticles. Preferably, the iron phosphide nanoparticles are rod-shaped particles, and the maximum length of the rod-shaped particles in the long axis direction is less than 100 nm. The deoxygenation catalyst is preferably a deoxygenation catalyst for sulfoxide compounds.

The application discloses high-compaction low-iron-dissolution lithium iron phosphate and a preparation method and a lithium battery thereof, and belongs to the technical field of lithium ion battery cathode materials. The preparation method comprises the following steps: mixing, granulating, drying a phosphoric acid iron precursor, a lithium source and a carbon source, and then sintering in a sintering kiln, wherein a mixed atmosphere mainly composed of nitrogen and containing trace oxygen is used in a high-temperature reaction section, the volume fraction of oxygen is 50ppm-3000ppm, and the temperature of the high-temperature reaction section is 800 DEG C-840 DEG C; and the target product is obtained after cooling, crushing and iron removal. By introducing controlled trace oxygen in the high-temperature crystallization section, the generation of iron phosphide by-products is inhibited, the compaction density of the obtained lithium iron phosphate material powder is not lower than 2.60g / cm 3 , the iron ion dissolution rate is not higher than 20mg / L, and the cycle stability is good. The method has strong process amplification and is suitable for continuous and large-scale production of high-compaction lithium iron phosphate materials for large-capacity energy storage cells.