88 results about "Lattice oxygen" patented technology

The invention discloses a La2O3-ZnO-NiO / ZrO2 oxygen carrier as well as a preparation method and application thereof, and belongs to the technical field of ammonia decomposition. According to the technical scheme, the method comprises the following steps: 1) synthesis of a ZrO2 carrier: adding NH3.H2O into a zirconyl nitrate solution to induce precipitation; 2) preparation of La2O3 / ZrO2: adding lanthanum nitrate hexahydrate and urea to obtain a precipitate, drying the precipitate, and finally calcining the precipitate; 3) preparation of La2O3-ZnO / ZrO2: adding zinc nitrate hexahydrate and urea, standing to obtain a precipitate, drying and calcining; and 4) preparation of La2O3-ZnO-NiO / ZrO2: adding NH3.H2O, then adding nickel acetate and thiourea, reacting, drying, and calcining twice to obtain the target product. Lattice oxygen in the oxygen carrier is used for catalytic oxidation of ammonia decomposition, the oxygen carrier can be recycled for multiple times, and the method is suitable for industrial application in the future.

The invention relates to a lithium ion battery positive electrode material regeneration method based on the synergistic effect of Nb < 5 + > / Ta < 5 + > / Mo < 6 + > doping and molten salt reconstruction, and belongs to the technical field of lithium battery material recovery and regeneration, a high-temperature molten salt system represented by LiOH-NaCl / Na2SO4 is adopted, NbCl5 / TaCl5 / MoCl6 is introduced as a dopant, and synchronous implementation of structure repair and Nb < 5 + > / Ta < 5 + > / Mo < 6 + > doping is realized in the lithium supplement reconstruction process, so that the lithium supplement reconstruction process is simplified, and the lithium ion battery positive electrode material regeneration method is suitable for large-scale popularization and application. Meanwhile, various structural defects such as lithium vacancies, cation mixing, lattice oxygen loss and particle cracks in the retired high-nickel positive electrode material are repaired, doped elements enter lattices at high temperature to form high-bond-energy O-TM bonds, surface lattice oxygen can be effectively anchored, oxygen vacancy generation and oxygen separation are inhibited, and the service life of the positive electrode material is prolonged. Therefore, the structural stability of the regenerative positive electrode under high voltage is remarkably improved. Meanwhile, a lithium ion diffusion channel is widened by doping Nb < 5 + > / Ta < 5 + > / Mo < 6 + >, the material has more excellent rate capability and long cycle stability in combination with a grain boundary elimination effect brought by crystal reconstruction, and the material has wide adaptability and good industrial popularization prospects.

The invention belongs to the technical field of electro-catalysis, and particularly relates to a short-range ordered neodymium element doped iridium oxide catalyst, an iridium oxide-based catalyst and a preparation method and oxygen evolution application thereof. The preparation method comprises the following steps: reacting iridium source metal salt with strong alkali, then carrying out alkali-assisted co-precipitation reaction with neodymium source metal salt to form iridium-neodymium co-coordinated hydrated hydroxide, and then sequentially carrying out drying, heat treatment and acid treatment to obtain the short-range ordered neodymium element doped iridium oxide catalyst. According to the method, the amorphous iridium oxide matrix dominated by side sharing [IrO6] connectivity is directly generated, meanwhile, low-valence Nd < 3 + > cations with large ion radius and obvious oxyphilicity are in a short-range frame of the amorphous iridium oxide matrix so as to synergistically activate an OPM oxide path mechanism, and the OPM oxide path mechanism overcomes the technical defects existing in an existing LOM lattice oxygen mechanism.

The present invention relates to the technical field of catalysts, and specifically relates to a high-activity cerium-zirconium composite oxide, and a preparation method therefor and a catalytic application thereof. The cerium-zirconium composite oxide has a general chemical formula of CexZryTzO2-αRδ, wherein, in terms of molar content, 0<x≤0.95, 0<y≤0.95, 0<z<0.3, x, y, and z satisfy x+y+z=1, 0≤α≤0.2, and 0≤δ≤0.1. The surface of the cerium-zirconium composite oxide contains adsorbed oxygen species, wherein an XPS peak intensity ratio of adsorbed oxygen to lattice oxygen, i.e., IOads / (IOads+IOlatt), is 0.3-0.8. In the present invention, the generation of more adsorbed oxygen species on the surface of the cerium-zirconium composite oxide is induced by constructing a non-uniform rare earth element doping structure and a grain boundary defect structure, and regulating and controlling the surface acidity and alkalinity. The adsorbed oxygen species on the surface can directly act as active oxygen to participate in a low-temperature catalytic reaction process, thereby promoting the activation of free O2, improving oxygen mobility and low-temperature co-catalytic activity, inhibiting the migration, agglomeration and growth of precious metals at high temperatures, and synergistically improving the high-temperature dispersity and catalytic activity of precious metals.

The application discloses a preparation method and application of a zirconium dioxide loaded iridium oxide nanocluster oxygen evolution electrocatalyst. A mixed solution of zirconium salt, amide solvent and organic acid is prepared, and the mixed solution is kept at 120 DEG C for 24 hours; after cooling, the white product is separated, washed and dried. Then, the product and iridium salt are dispersed in a mixed solution of tetrahydrofuran and water, and sodium nitrate and potassium nitrate aqueous solution are added under stirring; after stirring, rotary evaporation is carried out at 60 DEG C, and the greenish powder obtained after drying is vacuum dried at 60 DEG C for 12 hours; the greenish powder is kept in a muffle furnace at 450 DEG C for 30 minutes, and then cooled in air; the greenish powder is washed with deionized water and anhydrous ethanol for multiple times, and finally vacuum dried at 60 DEG C for 12 hours. The zirconium dioxide loaded iridium oxide material based on oxygen overflow stable tetragonal zirconia can be specially applied to an electrocatalyst for an oxygen evolution reaction in an acidic electrolyte, has excellent oxygen evolution reaction activity, follows a lattice oxygen mechanism in the reaction process, and can realize an oxygen overflow effect from tetragonal zirconia to iridium oxide nanoclusters to stabilize the catalyst.

The invention discloses application of a cobalt-based catalyst in preparation of ethylene by photocatalytic ethane dehydrogenation with participation of lattice oxygen, the cobalt-based catalyst is Co3O4 with a spinel structure, and due to the coexistence characteristic of Co < 2 + > / Co < 3 + > in the structure and the migration ability of the lattice oxygen, the cobalt-based catalyst can be used as a photocatalyst and an oxygen storage tank; therefore, under the environment-friendly and low-energy-consumption photocatalytic reaction condition, lattice oxygen can be used as a mild oxidizing agent for high-selectivity photocatalytic ethane dehydrogenation to prepare ethylene. Direct participation of oxygen molecules is avoided through utilization of lattice oxygen in the catalyst, generation of COx by-products caused by excessive oxidation can be prevented, ethylene selectivity is improved, the lattice oxygen consumed in the catalyst after the reaction can be regenerated through reaction with air or oxygen, the safety problem that ethane and oxygen are mixed and combustible is solved, and the catalyst is suitable for industrial production. And the feasible photocatalytic oxidation-reduction cycle is realized.

The invention provides a preparation method and application of an amorphous zirconium-doped manganese oxide catalyst, and belongs to the field of organic catalytic synthesis. The catalyst is Zr-MnO2-x, and is rich in lattice oxygen with high activity and high stability; x is the molar ratio of Zr to the sum of Mn and Zr, and x is larger than or equal to 0.2 and smaller than or equal to 0.6; zirconium mainly exists in the form of zirconium hydroxide. The preparation method comprises the following steps: slowly dropwise adding a mixed salt solution of a zirconium source and a manganese source into a precipitant under a continuous stirring condition, and carrying out a co-precipitation reaction; after the reaction is completed, standing and aging, carrying out solid-liquid separation and collecting a precipitate; and washing and drying to obtain the amorphous zirconium-doped manganese oxide catalyst which is used for catalyzing aniline and derivatives thereof to synthesize azobenzene compounds. According to the invention, the characteristic of'difunctional lattice oxygen 'with high activity and high stability is introduced through zirconium doping, and the catalyst has the advantages of high activity, high selectivity, wide substrate applicability, excellent stability and reusability and the like when used for catalytic synthesis of azobenzene compounds.

The present invention provides a carbon cycle rich aromatics catalyst and its preparation method. The catalyst includes a carrier, an active component and nano-scale activated carbon AC, the carrier is a ZSM-5 zeolite molecular sieve, and the pore size distribution is 0.2-0.4nm, the active component is ZnO inside the molecular sieve channel and ZnZrOx dispersed on the outer surface of the molecular sieve; the mass ratio of each substance of the catalyst is 100ZSM5: 6-9ZnO: 6-20ZnZrOx: 1-5AC, Zn modified ZSM5 molecular sieve is subjected to post-processing recrystallization means, the B acid acidity and pores of the ZSM5 molecular sieve are adjusted, and a metal salt is added in an alkaline environment in the later stage of recrystallization to form a metal oxide shell on the surface of the ZSM5 molecular sieve, and the lattice oxygen defects of the metal oxide are used to improve the adsorption capacity and conversion capacity of carbon dioxide. The addition of activated carbon also solves the diffusion problem of the outer surface. The present invention catalyzes the co-conversion reaction of carbon dioxide and light alkanes under milder reaction conditions to obtain higher carbon dioxide, alkane conversion rate and aromatics selectivity.

This invention discloses a heavy p Preparation methods of transition metal-modified transition metal coordination polymers and their application in seawater electrolysis for hydrogen production, in the fields of transition metals, heavy metals, and heavy metals. p In the presence of both metal and complexing agent, a one-step co-precipitation method was used to prepare heavy metals. p Transition metal coordination polymers modified with region metals. The heavy metals prepared in this invention... p Transition metal-modified polymers can be used to modify transition metal coordination polymers through heavy metal modification. p The strong Lewis acidity of the metal in the region repels chloride ions, inhibiting the chlorination side reaction, and can also pass through the heavy metal. p The polarization of the metal in the region activates the lattice oxygen oxidation mechanism, lowering the energy barrier for seawater oxidation reactions. p The anion exchange membrane seawater electrolyzer constructed using a transition metal coordination polymer modified with a metal zone as the anode exhibits both excellent reactivity and corrosion resistance, demonstrating significant application prospects in the field of direct seawater electrolysis. This invention utilizes low-cost raw materials, employs a simple preparation process, and is feasible and economical for large-scale production.

The application belongs to the technical field of organic solid waste resource utilization and high-value conversion, and specifically discloses a dual-phase rare earth metal-based high-entropy oxygen carrier for waste plastic gasification, a preparation method and application thereof. a Ni b Co c Mg d M e O y , wherein a, b, c, d and e are respectively 5% to 35% of atomic percentage, a+b+c+d+e=100% is satisfied, M is a rare earth metal Ce or La, and y is in the range of 0 to 4 but not 0. The dual-phase structure formed after the introduction of the rare earth metal enhances the surface oxygen vacancy content of the oxygen carrier, is beneficial to the migration of the lattice oxygen to participate in the gasification reaction, the high-entropy oxygen carrier lattice is distorted, the metal-oxygen bond is weakened, and then the oxygen release capacity is promoted, the catalytic cracking capacity for waste plastics is improved, and the syngas yield and the oxygen carrier circulation stability are improved. The preparation method of the oxygen carrier is simple, can be widely used in the field of waste plastic gasification, and has high use value.

The invention relates to the technical field of ethylbenzene dehydrogenation, in particular to a preparation method and application of a spinel CoFe2O4 oxygen carrier, and the preparation method comprises the following steps: dissolving cobalt salt and iron salt in water according to a specific molar ratio, adding ethylene glycol, methanol and a polymethyl methacrylate template agent, uniformly mixing, drying, carrying out programmed temperature rise calcination in an oxygen-containing atmosphere, and calcining to obtain the spinel CoFe2O4 oxygen carrier. The CoFe2O4 oxygen carrier with a single spinel crystal structure is obtained. The oxygen carrier is used as a recyclable lattice oxygen source and can catalyze ethylbenzene oxidative dehydrogenation to generate styrene at the ultralow temperature of 200-400 DEG C, especially about 250 DEG C, both the ethylbenzene conversion rate and the styrene selectivity can reach 96% or above, and the performance degradation rate is smaller than 5% after at least 41 times of redox cycles. The process conditions are mild, the oxygen carrier structure is stable, the activity is high, and a new way is provided for energy-saving and low-carbon production of styrene.

The application belongs to the technical field of chemical looping combustion, and discloses a nano oxygen carrier particle, a photo reactor and a chemical looping system. The nano oxygen carrier particle comprises a metal oxide, a noble metal / rare earth metal and a semiconductor material. The metal oxide has oxidizing property. The semiconductor material generates photo-generated holes and photo-generated electrons under light irradiation. The photo-generated holes have oxidizing property, and the photo-generated electrons have reducing property. The noble metal serves as a catalytic site and forms a Schottky barrier with the semiconductor. The Schottky barrier continuously captures the photo-generated electrons to improve the separation efficiency of the photo-generated electron-photo-generated hole pair. The application further discloses a photo reactor and a chemical reaction chain using the nano oxygen carrier. Through the application, the multifunctional nano oxygen carrier particle with lattice oxygen transfer, photocatalysis and thermal catalysis is synthesized, the operation temperature of the chemical looping system is below 200 DEG C, the low-temperature chemical looping combustion process is realized, and the sintering and agglomeration of the oxygen carrier material are avoided.

A positive electrode material is disclosed, represented by the formula LiaNixCoyMn1-x-yMbO2-cQc, where 0.2≤a≤1.2, x≥0.6, y>0, b>0, and c>0. M comprises a high-valence cation and Q comprises an anion. The doping of a high-valence cation and an anion in a nickel-rich ternary material stabilizes the bulk structure during lithium deintercalation, reduces side reactions, lattice oxygen release, and transition metal dissolution, and improves cycling stability, high-temperature storage, and rate capability. The outer surface of the positive electrode material may further include a selenium-containing coating layer that reacts with residual lithium compounds and binds released lattice oxygen to suppress electrolyte oxidation. A conductive coating layer may be formed on the selenium-containing layer to prevent direct contact with the electrolyte and inhibit side reactions.

The invention belongs to the technical field of organic solid waste recycling and high-value conversion, and particularly discloses a double-phase rare earth metal-based high-entropy oxygen carrier for waste plastic gasification and a preparation method and application of the double-phase rare earth metal-based high-entropy oxygen carrier. The oxygen carrier has a general formula of FeaNibCocMgdMeOy, a, b, c, d and e respectively account for 5%-35% of atoms, a + b + c + d + e = 100%, M is rare earth metal Ce or La, and y ranges from 0 to 4 but is not 0. The content of surface oxygen vacancies of the oxygen carrier is increased by a biphase structure formed after introduction of the rare earth metal, lattice oxygen migration is facilitated to participate in gasification reaction, lattice distortion of the high-entropy oxygen carrier occurs, metal-oxygen bonds become weak, oxygen release capacity is further promoted, catalytic cracking capacity on waste plastics is improved, and the catalytic cracking efficiency of the high-entropy oxygen carrier is improved. The yield of the synthesis gas and the cycling stability of the oxygen carrier are improved. The oxygen carrier disclosed by the invention is simple in preparation method, can be widely applied to the field of waste plastic gasification, and has relatively high use value.

The invention discloses a composite metal oxide catalyst based on grain boundary engineering, and a preparation method and application thereof, and belongs to the technical field of catalysts. The composite metal oxide catalyst is prepared on the basis of size effect induced crystal medium engineering. The catalyst can induce lattice oxygen to rapidly migrate and supplement by means of abundant crystal boundaries on the surface, meanwhile, electron transfer between bivariate valence metal elements contributes to the adsorption and oxidation process of reactants, and the catalyst can efficiently remove volatile organic compounds such as ethyl alcohol and formaldehyde in waste gas and efficiently purify CO pollutants in flue gas. The catalytic purification temperature window of flue gas and waste gas is effectively reduced, the temperature interval of catalytic oxidation reaction is widened, and the method has the advantages of wide applicability, high mineralization rate, good stability and the like. Meanwhile, the preparation method has the advantages of being low in cost, simple, feasible and suitable for mass production.

The invention discloses a molybdenum-doped cobaltosic oxide regulated bimetallic oxide catalyst with high-activity lattice oxygen as well as a preparation method and catalytic oxidation desulfurization application thereof. The structural formula of the molybdenum-doped cobaltosic oxide regulated and controlled bimetallic oxide catalyst with high-activity lattice oxygen is CoMoO4. The molybdenum-doped cobaltosic oxide regulated and controlled bimetallic oxide catalyst with high-activity lattice oxygen can be used for catalytic oxidation desulfurization, and the specific method comprises the following steps: mixing an oil product to be desulfurized and the molybdenum-doped cobaltosic oxide regulated and controlled bimetallic oxide catalyst with high-activity lattice oxygen, and carrying out ultrasonic treatment; and then air is introduced in a bubbling manner for reaction, so that deep desulfurization of the oil product to be detected is realized. The catalyst disclosed by the invention can realize an optimal catalytic effect without stirring in an environment with extremely low catalyst dosage, and the efficiency of catalytic oxidation desulfurization is remarkably improved; meanwhile, the catalyst is easy to recover and can be recycled, so that the use cost is greatly reduced.

The invention discloses a preparation method of a water-resistant sulfur-resistant ultralow-temperature CO oxidation catalyst. The preparation method comprises the following steps: firstly, preparing an alpha-SiO2 carrier with a rich (101) crystal face by adopting a hydrothermal method; afterwards, an inorganic anchoring-organic grafting strategy is combined, an HF solution is used for conducting functionalization treatment on the surface of alpha-SiO2, methyl silicon trichloride is introduced, a Si-F-O-C-Si bonding structure is constructed, and the precious metal is accurately loaded on the bonding structure by means of a precursor in an organic grafting mode. The Si-F-O-C-Si bond not only regulates the surface electronic structure of alpha-SiO2 and inhibits the adsorption of SO2 on the active site of noble metal, but also can reduce SO2 by carbon atoms to prevent the oxidation process of SO2 on active lattice oxygen on the surface of the carrier; meanwhile, the F-O bond can rapidly provide reactive oxygen species for the Pt site, and CO oxidation reaction is promoted. Based on the design of the water-resistant and sulfur-resistant system, the prepared noble metal-based C-F-alpha-SiO2 catalyst shows excellent CO oxidation activity at the temperature of 80-110 DEG C.

The invention provides a method for promoting low-temperature densification of yttria-stabilized zirconia and application, and belongs to the technical field of high-temperature solid oxide fuel cells. The nano-powder prepared by a sol-gel method is small in particle size, large in specific surface area and high in activity, so that the densification temperature of the nano-powder is reduced, the nano-powder is sintered in a vapor-containing atmosphere, the oxygen partial pressure under high-temperature vapor is reduced, lattice oxygen escapes to form oxygen vacancies, meanwhile, hydrogen proton defects generated by hydrolysis reduce the formation energy of cation defects, and the oxygen vacancies are reduced. Formation of defects is promoted, and oxygen vacancies and the defects provide channels for atomic diffusion; and hydroxyl adsorbed on the surface of the YSZ and cations form ionic bonds, the diffusion rate of OH <-> is far higher than that of O2 <->, and due to electrostatic interaction, diffusion of cations is further promoted, so that sintering of the YSZ is promoted, and low-temperature densification of the YSZ is realized.

The invention relates to the technical field of chemical industry, in particular to a method for preparing styrene by oxidative dehydrogenation of ethylbenzene, which comprises the following steps: under the condition of low temperature of 150-300 DEG C, ethylbenzene is contacted with an oxygen storage catalyst in an oxidation state, the catalyst catalyzes ethylbenzene dehydrogenation to generate styrene and hydrogen, and then the hydrogen is selectively oxidized into water by self lattice oxygen, directional movement of reaction balance is realized; the catalyst consuming lattice oxygen is regenerated through oxygen-containing gas flow to recover the oxidation state and is recycled. The oxygen storage catalyst is a composite metal oxide or carbide-oxide composite material with a specific structure, and has the functions of ethylbenzene activation, lattice oxygen storage and release and molecular oxygen activation. The invention also provides two reactor implementation schemes of fixed bed switching and fluidized bed circulation. The problems that traditional high-temperature dehydrogenation is high in energy consumption and limited in selectivity and existing oxidative dehydrogenation uses pure oxygen to cause safety and excessive oxidation are solved, and low-temperature, efficient and safe styrene production is achieved.

The invention relates to the technical field of solid oxide electrolytic cells, in particular to an A-site high-entropy perovskite oxide with oxygen octahedron distortion and a preparation method and application thereof. The chemical formula of the oxide is Nd < 0.2 > Pr < 0.2 > La < 0.2 > Ba < 0.2 > Sr < 0.2 > CoO < 3-delta >, wherein delta is the oxygen vacancy content. The oxide has lattice oxygen after being subjected to high entropy, so that oxygen ions move more easily, the oxygen evolution reaction activity is improved, meanwhile, the local environment of the oxygen ions is changed after high entropy, local oxygen octahedral distortion occurs, the oxygen ions are more active, the oxygen migration rate is further increased, the high oxygen evolution reaction activity is shown, and the oxygen evolution reaction activity is improved. Therefore, the yield of cathode carbon monoxide is improved.

The application discloses a La2O3-ZnO-NiO / ZrO2 oxygen carrier and a preparation method and application thereof, and belongs to the technical field of ammonia decomposition. The technical scheme comprises the following steps: 1) synthesis of a ZrO2 carrier: adding NH3H2O into a zirconyl nitrate solution to induce precipitation; 2) preparation of La2O3 / ZrO2: adding lanthanum nitrate hexahydrate and urea to obtain a precipitate, drying and finally calcining; 3) preparation of La2O3-ZnO / ZrO2: adding zinc nitrate hexahydrate and urea, standing to obtain a precipitate, drying and calcining; and 4) preparation of La2O3-ZnO-NiO / ZrO2: adding NH3H2O, then adding nickel acetate and thiourea, reacting, drying and twice calcining to obtain a target product. The application adopts lattice oxygen in the oxygen carrier to catalyze and oxidize ammonia gas decomposition, the oxygen carrier can be used repeatedly, and is suitable for future industrial application.

The invention discloses an A / B / O three-position composite doped LLTO solid electrolyte ceramic material and a preparation method thereof, aiming at A-position Li < + > ions of a Li < 0.33 > La < 0.56 > TiO < 3 > ceramic material, high-valence ions M with high electronegativity are adopted to carry out A-position partial substitution, aiming at B-position Ti < 4 + > ions, low-valence ions Sb < 3 + > with high electronegativity are adopted to carry out B-position partial substitution, aiming at O-position O < 2-> ions, o-site partial substitution is performed by adopting high-electronegativity low-valence ions F <->, so that a stable and high-conductivity cubic phase crystal form of a high-electronegativity element is introduced, a lithium ion channel is widened, the electronic insulation performance of the material is improved, an electricity price compensation mechanism is triggered by utilizing non-equivalent substitution, more cation vacancy defects are generated in unit cells, and the performance of the material is improved. The oxygen vacancy concentration at the grain boundary is reduced by utilizing a lattice oxygen transition mechanism, and positive charge enrichment at the grain boundary is inhibited; and by utilizing the electricity price difference between O < 2-> and F <->, cation vacancies with certain concentration are ensured to exist in unit cells, certain cation vacancies are formed at the grain boundary, and the grain boundary conductivity of the material is improved, so that a novel environment-friendly solid electrolyte material with excellent comprehensive performance is formed. The preparation method is low in sintering temperature, low in preparation cost, simple in process and easy to operate, influence factors are easy to control, and the preparation method is suitable for large-scale industrial production and beneficial to popularization and application.

The invention discloses a preparation method of an oxygen-vacancy-rich hollow double-shell composite material and n-butanol gas-sensitive application of the oxygen-vacancy-rich hollow double-shell composite material, and belongs to the technical field of gas sensors. The preparation method comprises the following steps: firstly, preparing a ZnSn (OH) 6 microsphere precursor through a simple coprecipitation method, and then carrying out in-situ pyrolysis in the microsphere to release H2O / CO2 by utilizing annealing treatment and controlling the heating rate so as to form a hollow double-shell layer; meanwhile, the outward diffusion time of lattice oxygen is prolonged at a relatively low heating rate, and a large number of oxygen vacancies are generated under the driving of non-equilibrium thermodynamics and are enriched on a ZTO / SnO2 heterogeneous interface. Oxygen vacancy is used as an n-type surface donor energy level, so that the carrier concentration is improved, and rich active adsorption sites are provided for n-butyl alcohol; the hollow double-shell layer shortens the diffusion distance and increases the specific surface area, so that target gas quickly reaches a sensitive interface, the oxygen vacancy-heterojunction synergistic effect remarkably enhances the chemical adsorption oxygen O2- / O-concentration, and specific catalysis is shown on n-butyl alcohol C-H bond breakage, so that high response, high selectivity and long-term stability are realized.

The invention discloses a supported Mn-based catalyst and a preparation method and application thereof, the catalyst takes a Y-type molecular sieve with high crystallinity, large specific surface area and large pore volume as a carrier, and manganese with outstanding low-temperature redox activity, low price and low toxicity is selected as a supported metal. And the catalyst is used for treating VOCs, so that the emission of VOCs is reduced, and toluene is subjected to catalytic oxidation. The manganese element is loaded on the Y-type molecular sieve, the supercage aperture of the Y-type molecular sieve is matched with that of toluene molecules, MnOx can be confined into a highly dispersed cluster of 2-3 nm, sufficient active sites are exposed, and sintering is inhibited; the strong acidity and exchangeable skeleton oxygen cooperate to promote toluene adsorption-activation, the lattice oxygen migration rate is high, the material has good hydrothermal stability and regeneration performance, and long-period operation is guaranteed without inactivation. And the toluene conversion rate of the catalyst can reach 100% within 1 hour under the condition of low load of manganese metal.

The invention discloses a silicon nitride ball for drilling equipment and a preparation method and application thereof, and belongs to the technical field of silicon nitride ceramic preparation. According to the technical scheme, the silicon nitride ball is provided, and raw materials of the silicon nitride ball comprise silicon nitride powder and an oxide auxiliary agent; the total nitrogen-to-oxygen ratio in the raw materials is 8.5-13; in the silicon nitride powder, the content of alpha-Si3N4 is greater than or equal to 95%; the silicon nitride powder comprises the following components in percentage by mass: 20%-30% of nano rod-shaped silicon nitride and 70%-80% of granular silicon nitride. By controlling the N / O ratio, the grain boundary glass phase can be reduced, the grain boundary bonding strength can be increased, the bending strength can be improved, lattice oxygen can be reduced, and the heat conductivity of the ceramic ball can be improved; according to the present invention, the combination of the nanorod-shaped morphology and the particle-shaped morphology is selected, the nanorod-shaped morphology can delay the crack through the bridging effect, the particle-shaped morphology is used as the matrix to provide the support so as to significantly improve the fracture toughness and the bending strength of the ceramic ball, and the nanorod alternately grows in the particle gap to form the three-dimensional interlocking mechanism so as to solve the defect of easy layered stripping of the traditional silicon nitride ball;

The application provides a two-dimensional flower-shaped Cu 0.5 Co 2.5 O4 spinel, a preparation method and application thereof, and the method uses Co(NO3)2.6H2O and Cu(NO3)2.3H2O as raw materials, isopropanol and glycerol as solvents, and NaBH4 as a reducing agent, and obtains two-dimensional flower-shaped Cu 0.5 Co 2.5 O4 spinel through a combination of hydrothermal treatment, pyrolysis and reduction. 0.5 Co 2.5 The flower-shaped Cu 3+ Co 2+ O4 spinel prepared by the application has high crystallinity and high purity, and has good reproducibility; the synergistic effect between Co and Cu can significantly improve the ratio of Co / Co, and a large number of oxygen vacancies are generated, so that more active centers are shown; the content of oxygen vacancies is further improved after reduction of NaBH4; the rich oxygen vacancies are beneficial to generation and migration of lattice oxygen, so that the low-temperature thermal catalytic oxidation performance of toluene of the catalyst is improved, and the catalyst is a very promising toluene oxidation catalyst; by adjusting the Cu doping amount, the specific surface area and pore structure of the spinel can be effectively improved, so that more active sites are exposed.

This application discloses a lithium-rich manganese-based cathode material, its preparation method, and its applications, relating to the field of lithium battery technology. A gradient lithium distribution is used to design a stable lattice oxygen framework, reducing lattice oxygen escape. This not only reduces gas production but also prevents transition metal ion migration and stabilizes the crystal structure, thereby improving cycle stability. A further coating with a layer of Mn3O4 material containing oxygen vacancies traps the escaped oxygen from the outermost layer and suppresses irreversible phase transitions during charge and discharge, preventing direct contact between the electrolyte and the cathode material and reducing side reactions. Therefore, the lithium-rich manganese-based cathode material provided in this application can isolate lattice oxygen evolution, stabilize the crystal structure, and reduce side reactions, thereby improving electrochemical performance.

The application discloses a positive electrode capable of limiting lattice oxygen escape, and a preparation method and application thereof. The specific method is to add a lattice oxygen inhibitor into the positive electrode in the secondary battery. The lattice oxygen inhibitor can not only play a role of a "physical passivation film" to constrain the particle volume change and prevent direct contact between the electrode and the electrolyte, but also play a role of an "electron reservoir" to inhibit the loss of the interface lattice oxygen and the conversion of the harmful interface phase transition in a way of interface charge compensation. The two aspects greatly inhibit the lattice oxygen release of the nickel-rich layered oxide, lithium cobaltate, lithium manganate, lithium-rich manganese-based and sodium-based layered oxide positive electrode material at high temperature, weaken the chemical crosstalk reaction between the active oxygen and the organic solvent and the lithiated negative electrode. Therefore, the heat accumulation of the thermal runaway trigger point can be effectively suppressed, the occurrence of the battery thermal runaway is delayed or avoided, and the safety of the battery is improved.

The application discloses a chemical cycle hydrogen production system and method, which is a circulation system in which an oxygen carrier sequentially and independently participates in reactions in a conversion unit, a hydrogen production unit and an oxidation unit. The conversion unit comprises a conversion reactor which uses methane as bed fluidization air to fluidize the oxygen carrier in the bed and perform a lattice oxygen partial oxidation reaction in a non-complete combustion state to obtain CO and H2 synthesis gas products. The conversion reactor extends downward to a riser section at the bottom. A deep reduction reactor receives the oxygen carrier transported from the riser section of the conversion reactor in a dense phase and performs primary gas stripping using the CO and H2 synthesis gas as fluidization air. H2 produced by the hydrogen production unit is introduced into the bottom of the riser section of the deep reduction reactor as fluidization air to perform secondary gas stripping on the oxygen carrier in the deep reduction reactor. The oxygen carrier is deeply reduced in the process of the two gas strippings and the synthesis gas products in the conversion reactor are prevented from entering the hydrogen production unit.

The present invention provides a high entropy oxide oxygen carrier and its preparation method and application. The chemical formula of the high entropy oxide oxygen carrier of the present invention is (Co x Ca y Cu z Al r Mg s )Fe2O4, which is a high-entropy oxide spinel-type oxygen carrier, addresses the three major problems of the current spinel-type chemical looping hydrogen production technology: low lattice oxygen activity and low hydrogen production at low temperatures; oxygen carriers are easily sintered and deactivated at high temperatures and cannot be effectively recycled; they cannot be regenerated in an H2O atmosphere and require the addition of an oxygen reactor, which makes the equipment complex. The high-entropy oxide oxygen carrier provided by the present invention has achieved good results, producing 99.9% pure hydrogen at 800°C, and no obvious attenuation was observed in 30 cycles of CO2 decomposition experiments. (In chemical looping technology, traditional CoFe2O4 spinel has lower hydrogen yield and output under the same conditions, and the oxygen carrying capacity was reduced by more than 50% in 10 CO2 decomposition cycle experiments).