28 results about "Selenium metallicum" patented technology

The application belongs to the technical field of materials, and provides a preparation method of transition metal selenide / metallic phase molybdenum disulfide in-plane heterostructure and application thereof. The method is to take metallic phase molybdenum disulfide nanosheet as a main body, embed 2-5 nm transition metal selenide nanoclusters into the interior of the metallic phase molybdenum disulfide nanosheet, and make the two be in the same plane. The specific steps are as follows: a transition metal sulfide in-plane heterostructure prepared by a two-step hydrothermal method is used as a precursor, a gas phase selenization method is used to convert the in-plane transition metal sulfide into its selenide under the premise of retaining the metallic phase molybdenum disulfide, and a transition metal selenide / metallic phase molybdenum disulfide in-plane heterostructure is obtained. The prepared transition metal selenide / metallic phase molybdenum disulfide in-plane heterostructure powder and self-supporting electrode are used as a water electrolysis hydrogen evolution catalyst. The preparation process is simple, the price is low, and the method is green and environment-friendly. The material has super-high catalytic activity as the water electrolysis hydrogen evolution catalyst.

The invention relates to the technical field of nano material preparation and application, in particular to a transition metal selenide catalyst and a preparation method and application thereof.The preparation method comprises the steps that firstly, metal nickel salt, ferric salt, urea and ammonium fluoride are dissolved in deionized water, and a nickel-iron layered hydroxide nanosheet precursor is synthesized through a hydrothermal method; secondly, preparing an iron-doped nickel selenide catalyst by adopting a selenylation reaction; the electronic structure of nickel selenide is regulated and controlled by utilizing an iron doping strategy, and the catalytic performance is improved. The prepared iron-doped nickel selenide catalyst has good catalytic activity when being used for hydrogen evolution reaction and sulfur ion oxidation reaction. In a two-electrode sulfur ion oxidation coupling hydrogen production electrolytic tank, the current density of 10mAcm <-2 > can be output only by the voltage of 0.439 V, and the targets of efficient and energy-saving hydrogen production and sulfur ion oxidation upgrading into a high-added-value elemental sulfur product are achieved. The method has the advantages of simple and controllable preparation process, low raw material price, easiness in batch production and the like, and can be used as a catalyst for efficient water electrolysis hydrogen production and sulfur ion oxidation reaction.

The present invention discloses a metal selenide nano-silicon-carbon composite material and its preparation method, application and battery. The preparation method comprises: (1) calcining a mixture of transition metal M and silicon powder under inert gas protection to obtain a metal precursor; (2) calcining a mixture of the metal precursor and SeCl4 under inert gas protection, and then washing to obtain a metal selenide nano-silicon composite material; (3) granulating and carbonizing a mixture of the metal selenide nano-silicon composite material and a carbon source to obtain the metal selenide nano-silicon-carbon composite material. The preparation method of the present invention can simultaneously prepare nano-sized metal selenides and silicon materials, and the prepared metal selenide nano-silicon-carbon composite material has excellent high-rate specific capacity and cycle life.

This invention relates to the field of two-dimensional selenide technology, specifically to a class of two-dimensional transition metal selenides and their preparation method. The method first mixes transition metal oxophosphate powder and selenium-containing salt powder in a certain molar ratio and places them in a tube furnace. Then, the mixed salt reacts at high temperature to generate two-dimensional transition metal selenides. The two-dimensional transition metal selenides are then heated and deposited on a growth substrate to obtain single-layer / multi-layer two-dimensional transition metal selenides. The method for preparing single-layer / multi-layer two-dimensional transition metal selenides of this invention has the characteristics of low energy consumption, simple operation, economy and strong universality.

The invention provides a transition metal selenylation carrier as well as a preparation method and application thereof, and relates to the technical field of battery positive electrode carriers. The preparation method provided by the invention comprises the following steps: mixing and coordinating a transition metal solution and an organic ligand, and separating to obtain a composite precursor; and mixing the composite precursor with selenium powder, and selenizing in a nitrogen-containing atmosphere to obtain the transition metal selenylation carrier. The selenylation carrier prepared by the invention can be used for effectively confining and packaging transition metal selenide, inhibiting agglomeration of nanoparticles and improving the surface activity of the carrier, and is beneficial to improving the rate capability and the cycle performance of the lithium-sulfur battery.

The invention discloses an iron-rich transition metal selenide electrolyzed water catalyst and a preparation method thereof. The iron-rich transition metal selenide electrolyzed water catalyst comprises a carrier and an iron-rich transition metal selenide loaded on the carrier, the method comprises the following steps: ultrasonically cleaning a carrier to remove oil stains and oxides on the surface of the carrier; the preparation method comprises the following steps: adding selenium powder into a mixed solution of water and hydrazine hydrate, carrying out sufficient magnetic stirring and ultrasonic dispersion until uniform mixing so as to obtain a mixed reaction solution, and transferring the mixed reaction solution and a carrier together into a polytetrafluoroethylene reaction kettle to carry out a reaction; and washing and drying the reaction product in sequence to finally prepare the iron-rich transition metal selenide electrolyzed water catalyst. The iron-base-rich transition metal selenide electrolyzed water catalyst is synthesized through a simple one-step hydrothermal method, the cost of needed raw materials is low, the preparation method is simple and easy to operate, the overpotential in the reaction process is reduced, the energy consumption of electrolyzed water is greatly reduced, and the iron-base-rich transition metal selenide electrolyzed water catalyst is suitable for industrial large-scale production.

The application discloses rhombic nanosheet-shaped copper-doped nickel-cobalt transition metal selenide and a preparation method and application thereof. The preparation method of the material is as follows: after a coordination agent, a surfactant, a nickel salt, a cobalt salt and a copper salt are mixed with a solvent, the mixture is placed in a microwave COD digester to perform a microwave-assisted solvothermal reaction, a copper-doped nickel-cobalt MOFs precursor is obtained; the copper-doped nickel-cobalt MOFs precursor and a selenite are respectively placed in the downstream and the upstream of a tube furnace, and a selenization reaction is performed under a protective atmosphere, and the rhombic nanosheet-shaped copper-doped nickel-cobalt transition metal selenide is obtained. The material has an ultrathin rhombic nanosheet-shaped structure, the surface of the material is rough, the particle size distribution of the material is uniform, and the material has excellent electrochemical performance; when the material is used as an electrode material of a supercapacitor, the capacitance performance can be greatly improved. The preparation process is simple, the conditions are mild, the time consumption is short, and the cost is low, and the preparation process meets the industrial production standards.

The invention discloses a metal selenide (at) MXene composite material and a preparation method and application thereof. The method comprises the following steps that 1, selenium powder and MAX are mixed, ground and mixed uniformly; and 2, calcining the product obtained in the step 1 in a protective atmosphere, and taking out the product after heat preservation to obtain the metal selenide and MXene composite material. The weight ratio of the selenium powder to the MAX phase is 10-1. And the MAX phase is any one of Ti2SnC, Ti2AlC, V2AlC, Cr2AlC, Ti2ZnC, Ti3AlC2, Mo2Ga2C, Ti3SiC2, V4AlC3 and (Ti < 0.5 > Nb < 0.5 >) < 5 > AlC4. The grinding time is 10-30 minutes. The preparation method disclosed by the invention is convenient, rapid and low in cost, can effectively utilize each component element in the MAX phase, does not generate pollution, and can realize large-scale industrial application; the prepared metal selenide (at) MXene composite electrode material has excellent interface bonding and can be applied to a secondary battery electrode material.

The invention belongs to the technical field of material preparation, and particularly relates to a preparation method of metal selenium and an ultrasonic enhanced impinging stream reaction system and method. According to the invention, an ultrasonic wave and impinging stream combined process is utilized, two reaction solution flow columns collide with each other, so that the contact specific surface area of the two reaction solutions and the effective collision probability between molecules are obviously increased, interphase transfer and micro-mixing of fluids are strengthened, the mass transfer rate is increased, and ultrasonic waves are introduced to strengthen the reduction reaction of selenium dioxide; pure selenium powder with good research prospects is obtained through one-step reduction of selenium dioxide, the preparation method provided by the invention realizes normal-temperature and normal-pressure reduction, the reduction efficiency is high, products are not easy to agglomerate, the reaction conditions are simple, the reaction process is short, and industrial production and application are very easily realized on the whole. According to the device, the impinging stream is adopted for preparing the pure selenium powder, and the pure selenium powder with higher purity can be more efficiently prepared through non-contact ultrasonic treatment, closed reaction equipment and no introduction of impurities.

A method of direct deposition of multinary metal polyselenide films, including precipitating alkylammonium polyselenide with an antisolvent, redissolution of precipitated alkylammonium polyselenide with a solvent, dissolving at least one metal source, such as elemental metal, a metal containing compound, or a combination thereof, in the solution containing polyselenide ions to provide a precursor solution, and using the precursor solution to fabricate metal polyselenides. The metal source is selected from the group consisting of Ag, Cu, Zn, Cd, In, Ga, Sn, Ge, As, Cu2Se, Cu2O, CuCl, and combinations thereof. The precursor solution is substantially sulfur-free.

The invention relates to the technical field of chemical power sources, in particular to a bimetallic selenide modified alkali metal negative electrode material and a preparation method and application thereof.The preparation method comprises the steps that prepared vanadium atom doped tungsten diselenide (VxWSe) powder is evenly coated on the surface of sodium / potassium metal, an adjustable interface protection layer is constructed, and the surface of the sodium / potassium metal is coated with the bimetallic selenide modified alkali metal negative electrode material; and the adsorption and transfer of sodium / potassium ions are optimized by utilizing the unique layered structure. The controllable interface protection layer can provide excellent dendrite growth prevention and desolvation functions, and the cycle life of the alkali metal battery is greatly prolonged by reducing side reactions. In addition, the preparation method has the advantages that the operation is simple, modification factors are easy to control, and large-scale production can be realized.

The invention discloses a porous graphene-based double transition metal selenide heterojunction composite material. The composite material comprises a porous graphene matrix and Ni0.85Se / CoSe polygonal nanoparticles loaded on the surface of the porous graphene matrix. According to the invention, a metal selenide heterojunction structure is constructed on a porous graphene matrix, so that a sodium ion cross-layer transport path can be effectively provided, and the graphene-based metal selenide heterojunction composite material has high ionic conductivity, small volume change in a working process, high reversible capacity and excellent rate and cycle performance; when the composite material is used as the negative electrode of the sodium ion battery, the selenide heterojunction structure close to the graphene hole can effectively reduce the structure and volume change, shorten the ion transmission distance, and effectively enhance the electrochemical stability and improve the capacity in the charging and discharging process; the sodium ion energy storage requirements of high specific capacity, long service life and safety can be met, and the method is suitable for popularization and application.

The application provides a nanoscale photothermal electric coupling energy platform and a preparation method and application thereof, and belongs to the technical field of nanobiomedical materials. The method comprises the following steps: dispersing ZIF-8 particles in an alcohol solvent of silver nitrate, introducing metal silver ions through ion exchange and / or adsorption; dispersing the ZIF-8 material loaded with metal silver ions in an alcohol solvent, dropping a selenium precursor solution prepared by dissolving a sulfide and elemental selenium powder in an organic solvent together, and generating uniformly distributed metal silver selenide nanoparticles in the confined space of ZIF-8 in situ. The obtained product is composed of a ZIF-8 carrier and uniformly dispersed metal silver selenide semiconductor nanoparticles, has a particle size of 300+ / -20 nm, and has a photothermal electric effect. The energy platform can be combined with a biocompatible matrix to form a flexible patch, a film or a coating, can promote cell proliferation, migration, collagen deposition or recovery of mitochondrial function, and is particularly suitable for treating diabetic skin wounds.

The application provides a method and equipment for separating selenium and tellurium from high-tellurium crude selenium raw materials. The method can selectively form tellurium polysulfide from tellurium in the crude selenium by adding sulfur in an alkaline solution, so that the metallic tellurium is converted into ions and enters the solution, and the main metallic selenium remains in the slag, thereby preliminarily and effectively separating the selenium and the tellurium, achieving a separation coefficient of 90.67%, and reducing the content of tellurium in the crude selenium raw material from 0.30% to 0.028%. The application has the advantages of good selenium and tellurium separation effect, simple operation, short process, and strong raw material adaptability.

The application provides a three-dimensional structured metal selenide flexible thermoelectric material and a preparation method and application thereof. 2+ The preparation method comprises the following steps: pretreating a flexible substrate with an alkali solution, and obtaining a substrate material after cleaning; dissolving a tin salt in water to prepare a Sn n solution, then adding acid until the solution becomes clear, immersing the substrate material in the clear solution for more than 10 min, and then cleaning and drying to obtain a template; depositing metal X on the surface of the template and the inner surface of the holes of the template to obtain a metalized substrate; wherein X is at least one of Cu, Ag and Sn; immersing the metalized substrate in a selenium solution for soaking, and reacting to obtain a three-dimensional structured X n Se metal selenide flexible thermoelectric material, wherein 2 >= n >= 1. By adopting the technical scheme of the application, the obtained thermoelectric material has high porosity, low density, low thermal conductivity and excellent flexibility.

The invention is applicable to the technical field of materials, and provides a preparation method and application of a transition metal selenide / metal-phase molybdenum disulfide in-plane heterostructure, a metal-phase molybdenum disulfide nanosheet is used as a main body, a 2-5nm transition metal selenide nanocluster is embedded into the metal-phase molybdenum disulfide nanosheet, and the transition metal selenide / metal-phase molybdenum disulfide in-plane heterostructure is prepared. And the two are in the same plane. The preparation method comprises the following specific steps: by taking a transition metal sulfide in-plane heterostructure prepared by a two-step hydrothermal method as a precursor, converting in-plane transition metal sulfide into selenide thereof by a gas-phase selenylation method on the premise of reserving metal-phase molybdenum disulfide, so as to obtain the transition metal selenide / metal-phase molybdenum disulfide in-plane heterostructure. And the prepared transition metal selenide / metal phase molybdenum disulfide in-plane heterostructure powder and a self-supporting electrode are used as a water electrolysis hydrogen evolution catalyst. The material is simple in preparation process, low in price, green and environment-friendly, and has ultrahigh catalytic activity as a water electrolysis hydrogen evolution catalyst.

The invention discloses a metal selenide nano composite material with simultaneously modified surface and interface as well as a preparation method and application of the metal selenide nano composite material, and belongs to the technical field of sodium-ion battery electrode materials. The preparation method disclosed by the invention comprises the following steps: dissolving a molybdenum source, a manganese source, a selenium source and an organic carbon source in a solvent, and then performing microwave radiation to form a precursor; and carrying out multi-step temperature-controlled calcination on the precursor to obtain the metal selenide nano composite material with simultaneously modified surface and interface. The invention provides a'heterojunction-carbon coating-nanocrystallization 'triple collaborative design, an electric field is built in the heterojunction, a three-dimensional conductive network is constructed through an atomic-scale Se bridging interface, sodium ion directional migration driving and amorphous carbon coating, and the overall electronic conductivity is improved.

The present invention discloses an ultra-high cycle stability amorphous selenide and its preparation method and application. Under room temperature stirring conditions, a polyoxometalate solution is adjusted to a neutral or alkaline pH value, and a hydrochloric acid dopamine solution is added to react to obtain metal-polydopamine; selenium powder is used to selenize the metal-polydopamine in an inert atmosphere to obtain a crystalline metal selenide; the crystalline metal selenide is doped with a heteroatom source that can form a doping atmosphere to obtain an amorphous heteroatom-doped metal selenide, that is, an ultra-high cycle stability amorphous selenide. The present invention is the first to propose a method for destroying the lattice structure by heteroatom doping to convert it into an amorphous form. The amorphous metal selenide negative electrode material has the advantages of many active sites, fast ion diffusion rate, extremely small volume expansion and good stability, and can be used as a new strategy to improve the electrochemical performance of secondary ion battery negative electrode materials.

The invention provides a bimetallic selenide heterojunction composite material and a preparation method thereof. The preparation method comprises the following steps: by taking graphite as an anode, an inert carrier as a cathode and mixed molten salt containing a first metal source and a second metal source as electrolyte, heating and melting, adding selenium particles into the molten salt, electrolyzing in a protective atmosphere, taking out a cathode product after the electrolysis is finished, washing and drying, thereby obtaining the selenium-enriched graphite. The bimetallic selenide heterojunction composite material grown in the confinement of the carbon nano tube is obtained. The preparation method is simple, reduction and selenylation of the metal oxide and in-situ growth of the carbon nano tube are realized in the high-temperature molten salt electrolyte in the whole process, a large amount of water or organic solvent depended by a traditional hydrothermal / solvothermal method is not needed, and tedious steps such as repeated filtration, washing, drying and re-selenylation are also avoided; therefore, solvent consumption and waste liquid discharge are greatly reduced, the environmental burden is relieved, and the treatment cost is saved.

This application relates to a bimetallic selenide nanoparticle composite material, preparation method, and application thereof, comprising: dissolving a transition metal source and a manganese source in a solvent, and preparing a transition metal-manganese polymer via a one-step hydrothermal method; mixing the transition metal-manganese polymer with selenium powder, and performing a selenization treatment under an inert gas atmosphere to obtain the bimetallic selenide nanoparticle composite material. This application can improve the conductivity of the material without carbon addition. The nanostructure accelerates sodium ion diffusion, and the fluffy volume mitigates the volume expansion caused by the reaction, thus opening up the application of selenium-based materials in sodium-ion batteries.

The invention discloses a sunflower-shaped hollow core-shell structure metal selenide (at) carbon heterojunction material and a preparation method and application thereof, and the method comprises the following steps: uniformly dispersing hollow Co-MOF-74 (at) ZIF-67 core-shell structure powder and 2, 5-dihydroxy terephthalic acid in N, N-dimethylformamide for reaction; after the reaction is finished, a product is centrifuged, washed and dried, and sunflower-shaped hollow Co-MOF-74 and MOF-74 core-shell structure powder is obtained. And annealing the sunflower-shaped hollow Co-MOF-74 (at) MOF-74 core-shell structure powder under the protection of argon, so as to obtain the sunflower-shaped hollow core-shell structure porous carbon hybrid material. Uniformly mixing the porous carbon hybrid material with the sunflower-shaped hollow core-shell structure with selenium powder, and annealing under the protection of argon to obtain the metal selenide and carbon heterojunction with the sunflower-shaped hollow core-shell structure. The product prepared by the method can be used for preparing a sodium-ion battery negative electrode material, and the electrochemical performance of the battery is improved.

The invention provides a preparation method of a hollow nitrogen-doped carbon nano square block material with co-existing cobalt monatomic and cobalt selenium nano particle sites. The method comprises the following steps: (1) synthesizing a metal organic framework precursor; (2) etching the metal organic framework material; and (3) carrying out temperature programming vapor deposition. Co single atoms and cobalt selenium nanoparticle sites are jointly loaded on the nitrogen-doped carbon nano substrate, the activity of the material for catalyzing the oxygen evolution reaction is greatly improved, the preparation process is simple, the cost of the needed raw materials is low, and the method is suitable for industrial production. A new design thought and a synthesis path are provided for preparing the transition metal selenide and a nano catalytic material with coexistence of monatomic and nano particles.

The invention discloses a preparation method and application of a bimetallic selenide / three-dimensional carbon composite material, belonging to the technical field of electrode materials. S1, prepare a graphene oxide aqueous solution, impregnate melamine foam, and freeze-dry after sufficient impregnation; S2, carbonize in a nitrogen atmosphere, wash and dry after heat preservation; S3, prepare Cu 2+ and Zn 2+ aqueous solution, take an equal volume of Cu 2+ and Zn 2+ Aqueous solution is used to impregnate the three-dimensional composite carbon; S4, placing it in a reactor for hydrothermal reaction, cooling it to room temperature after taking it out, cleaning it, centrifuging it, and vacuum drying it to obtain a precursor; S5, taking selenium powder and the precursor, placing them in a tube test furnace, and annealing them in an argon / hydrogen mixed gas to obtain a copper zinc selenide / three-dimensional carbon composite material. The present invention provides a preparation method and application of a bimetallic selenide / three-dimensional carbon composite material. The composite material has good electrochemical structure stability. The prepared composite material is used in a sodium ion battery, and the prepared electrode sheet has excellent cycle performance and excellent rate performance.

The invention relates to multifunctional MOFs derived metal selenide wave-absorbing powder and a preparation method and application thereof.The wave-absorbing material is of a core-shell structure with a (CozNi1-z) xSey substance as a core and a carbon coating layer as a shell, the wave-absorbing powder is of a porous hollow spherical microstructure, and the particle size ranges from 6 micrometers to 10 micrometers. The bimetallic MOFs-derived (CozNi1-z) xSeyat C composite material with adjustable components is successfully prepared by fully utilizing heterogeneous interface engineering and a multi-loss synergistic mechanism derived from bimetallic MOFs, regulating and controlling the wave-absorbing performance of metal selenide wave-absorbing powder by virtue of a solvothermal method and a high-temperature selenylation method and adjusting the temperature in the selenylation reaction and pyrolysis process, and has the advantages that the preparation method is simple, the cost is low, and the application prospect is wide. The tunable characteristic of the absorption frequency band is realized; besides, due to improvement factors such as a unique core-shell microstructure, a rich heterogeneous interface, excellent impedance matching and the like, the electromagnetic wave absorption (EMWA) performance of the composite material can be enhanced, sufficient electromagnetic wave absorption is achieved within the range of 2-18 GHz, the RLmin value of-51.5 dB and the EAB value of 4 GHz are included, and excellent electromagnetic wave absorption is achieved.

This invention discloses a method for preparing an infrared-transmitting material. By preparing a doped metal selenium sulfide and organically combining it with graphene, a material is obtained that is opaque in the visible light band (360-750nm) and translucent in the infrared band (750-1100nm), with a transmittance reaching 90%. The main steps include: (1) uniformly dispersing a stabilizer, zinc salt, copper salt, selenium oxide, and L-cysteine ​​in water sequentially; (2) adding a reducing agent solution dropwise under stirring to prepare a pre-product using a hydrothermal method; (3) sintering the pre-product at 900℃ to obtain a doped zinc-copper-selenium sulfide; (4) ultrasonically dispersing the pre-product with graphene oxide in ethanol, and adding vinyltriethoxysilane under acidic conditions to form an infrared-transmitting material. This composite material is simple to prepare, environmentally friendly, has high infrared transmittance, is stable and durable, and has excellent application prospects in information communication, infrared detection, and other fields.

The invention provides a multi-metal selenide heterojunction material, a preparation method and a battery negative electrode material, and the preparation method comprises the following steps: S1, synthesizing an ABC-PBA precursor through a coprecipitation method, adding the ABC-PBA precursor into a Tris-containing buffer solution, carrying out ultrasonic dispersion, adding dopamine, and stirring to obtain a black precipitate; s2, washing the precipitate with deionized water and ethanol, and drying to obtain ABC-PBA-coated PDA; and S3, respectively placing the ABC-PGA (at) PDA and Se powder at two ends of a crucible, and carrying out selenylation treatment to finally obtain the ASe2 / BSe2 / CSe2 (at) NC heterojunction material with the yolk shell structure. The heterojunction material is applied to a sodium-ion battery negative electrode material, and the specific capacity of 380-320 mAh g <-1 > can be maintained after circulation according to a cycle performance curve of 2000 cycles under the condition that the current density is 5 A g <-1 >.

The invention discloses a monometal selenide catalyst rich in selenium vacancy and having a heterostructure, and a preparation method and application thereof, and belongs to the field of catalysts. The preparation method comprises the following steps: S1, dissolving a single metal M salt and urea in deionized water to form a mixed solution A; then carrying out primary hydrothermal reaction to obtain a metal precursor; s2, NaBH4 and Se powder are dissolved in deionized water, and a clear solution B is obtained; then adding a metal precursor into the solution B, wherein the molar ratio of the element M in the metal precursor to the element Se in the selenium powder is (0.5-1.8): 1; and after ultrasonic dispersion, carrying out secondary hydrothermal reaction at 160-220 DEG C to obtain the product. According to the invention, controllable synthesis of nanosheets, nanotubes, nanoparticles and the like with different morphologies can be realized by regulating and controlling the structure of the precursor. Based on the regulation and control effect of heterogeneous interface engineering on the catalytic activity of an interface electronic structure and an active site, the catalyst shows excellent activity and selectivity in a double-electron oxygen reduction reaction, and the H2O2 selectivity can reach 97%.