238 results about "Selenide" patented technology

The invention relates to the technical field of crystal material preparation, in particular to a ternary layered selenide Ge3Sb4Se7 semiconductor material and a preparation method thereof. The preparation method of the ternary layered selenide Ge3Sb4Se7 semiconductor material comprises the following steps that S001, germanium powder, antimony powder and selenium powder with the molar ratio being 3: 4: 7 serve as raw materials, the temperature is increased to 900-950 DEG C under the vacuum condition, and heat preservation is conducted for 12-24 h at the temperature; s002, after heat preservation is finished, the temperature is reduced to 475-500 DEG C at the cooling rate of 1-5 DEG C / min, and heat preservation is conducted for 3-5 days at the temperature; and after heat preservation is finished, furnace cooling or quenching cooling is performed to reach the room temperature, and the layered ternary selenide single-phase material with the chemical formula being Ge3Sb4Se7 is obtained. The ternary layered selenide Ge3Sb4Se7 semiconductor material prepared by the invention is a single-phase material and has the characteristics of low thermal conductivity and low resistivity, so that the ternary layered selenide Ge3Sb4Se7 semiconductor material has application potential in the fields of thermoelectric devices, photoelectric detection and the like.

The invention discloses a preparation method of a rare earth element doped nickel-based selenide nano-material and application of the rare earth element doped nickel-based selenide nano-material in electro-catalysis water full-hydrolysis reaction. According to the method, nickel salt, cerium salt, selenium dioxide and potassium chloride are prepared into electrolyte, and the electrolyte is subjected to electro-deposition on a foamed nickel substrate to obtain Ce-doped Ni0.85Se nanoparticles growing on foamed nickel. The crystal structure and electron distribution of Ni0.85Se are optimized by doping trace rare earth element cerium, so that the HER and OER performances of the Ni0.85Se are greatly improved. The prepared catalyst is self-supporting closely-packed nanoparticles, the formed amorphous structure is easy to expose more active sites, the catalyst has good electrocatalytic hydrogen evolution and oxygen evolution performance under alkaline conditions, the overpotential in electrocatalysis of nickel-based selenide is greatly reduced, and the electrocatalytic performance of nickel-based selenide is improved. And excellent electro-catalytic activity is shown in electro-catalytic water full hydrolysis. And the self-supporting electrode is not easy to fall off due to generation of bubbles in the reaction process, so that the working stability of the catalyst is improved.

The invention relates to a preparation technology of an electrochemical catalytic material, and aims to provide a method for preparing an electrode material through pulse electrodeposition and application of the electrode material in an oxygen evolution reaction. The method comprises the following steps: constructing a dual-electrode electrolysis system, and co-depositing transition metal ions and selenium ions on a working electrode by adopting a pulse electrodeposition method to form a catalyst layer containing transition metal and selenide; then the working electrode is used for building an electrochemical system, electrochemical activation treatment is conducted on the working electrode through cyclic voltammetry, a selenium phase is induced to fall off, porous metal oxide is formed by reconstructing the surface of a catalyst layer, and the electrode material for the water electrolysis oxygen evolution reaction is obtained. The selenium phase is induced to fall off through electrochemical activation to form a porous metal oxide structure, the specific surface area is remarkably increased, rich oxygen vacancies are formed, the electronic structure is optimized, more active sites are exposed, and the catalytic activity is improved; the method is easy to operate, high in parameter controllability, free of high-temperature and high-pressure equipment and suitable for large-scale production.

The invention relates to a rapid biosynthesis method and antibacterial application of a photo-thermal nano material (Cu, Co) Se2. The method comprises the following steps: step 1, culturing dissimilatory metal reducing bacteria in a culture medium to a platform earlier stage, and activating; 2, the activated dissimilatory metal reducing bacteria are inoculated into an anaerobic culture medium, then bivalent copper salt and selenite are added, and Cu2-xSe nanoparticles are synthesized through a reaction under the anaerobic condition; wherein x is equal to 0-1; 3, divalent cobalt salt continues to be added under the anaerobic condition, thalli are separated into supernate through differential centrifugation, sediment is collected, and (Cu, Co) Se2 nanoparticles are obtained; step 4, carrying out cell disruption treatment on the (Cu, Co) Se2 nanoparticles; the light absorption range and intensity of the original selenide are improved, the photo-thermal efficiency of the selenide is enhanced, and the photo-thermal metal nano material (Cu, Co) Se2 can be efficiently, rapidly and controllably synthesized by the synthesis method.

The invention discloses a one-dimensional tubular selenide-carbon composite material assembled by hollow particles and a preparation method and application thereof.The preparation method comprises the following steps that ZnCo-ZIF nanotubes and 2, 5-dihydroxyterephthalic acid are mixed, N, N-dimethylformamide is added, a reaction is conducted, after the reaction is completed, a product is subjected to centrifugal separation, and the one-dimensional tubular selenide-carbon composite material assembled by the hollow particles is obtained. And washing and drying to obtain the one-dimensional tubular MOF material assembled by the hollow particles. And annealing the MOF material in an argon atmosphere to obtain the one-dimensional porous carbon nanotube material assembled by the hollow particles. And then uniformly mixing with selenium powder, and annealing under argon protection to obtain the one-dimensional tubular selenide-carbon composite material assembled by hollow particles. The method is simple to operate and controllable in process, and the prepared product is widely applied to the fields of energy storage, catalysis, environmental governance, biomedicine and the like.

The invention provides a chlorine corrosion resistant cathode for electrolyzing seawater as well as a preparation method and application of the chlorine corrosion resistant cathode. The preparation method comprises the following steps: S1, dissolving a cobalt salt, a nickel salt, a morphology regulating agent and a structure-directing agent in a solvent according to a molar ratio of (1-2.5): (1-2.5): (8-12): (6-10), and stirring to form a first solution; s2, a titanium mesh and the first solution are subjected to a hydrothermal reaction at the temperature of 100-150 DEG C, and CoNi layered double hydroxide with the shape of a nanoneedle array grows on the titanium mesh in situ; s3, selenium powder and a reducing agent are dissolved in a solvent according to the molar ratio of 1: (0.8-1.5) and stirred to form a second solution; and S4, carrying out hydrothermal reaction on the titanium mesh on which the CoNi layered double hydroxides grow in situ and a second solution at 150-190 DEG C so as to grow cobalt-nickel bimetallic selenide of which the morphology is a nanoneedle array in situ on the titanium mesh, thereby obtaining the chlorine corrosion resistant cathode.

The invention discloses a ruthenium / ruthenium selenide composite material and a preparation method and application thereof, and relates to the technical field of water electrolysis catalyst materials.The preparation method comprises the following steps that ruthenium salt is dissolved in deionized water, selenium powder is added under vigorous stirring, then a reducing agent is added and stirred to be uniform, then the mixture is transferred into a reaction kettle to be subjected to a hydrothermal reaction, and the ruthenium / ruthenium selenide composite material is obtained; after the reaction is finished, centrifuging, washing and drying are performed, the obtained product is sintered in an inert atmosphere, the Ru / RuSe2 composite material is obtained, controllable synthesis of the Ru / RuSe2 composite material is achieved through a hydrothermal-calcination two-step method in combination with parameter control and inert atmosphere protection, the problem that an existing catalyst is insufficient in activity and stability in an acid environment is solved, and the Ru / RuSe2 composite material is obtained. The Ru / RuSe2 heterojunction interface is regulated and controlled through electron transfer, so that the adsorption capacity of Ru sites to HER activity is optimized, the RuSe2 sites promote intermediate conversion in the OER process, one agent has double effects, the hydrogen evolution and oxygen evolution performance of electrolyzed water is effectively improved, the use amount of precious metal is reduced by introducing selenium into the composite material, the preparation process is simple, and the cost is reduced.

This invention relates to a compound, magnesium gallium selenide (MgHgGa4Se8), and a magnesium gallium selenide (MgHgGa4Se8) infrared nonlinear optical crystal, along with their preparation methods and applications. The compound has the molecular formula MgHgGa4Se8 and a molecular weight of 1135.46 g / mol. The crystal, also with the molecular formula MgHgGa4Se8 and a molecular weight of 1135.46 g / mol, lacks a center of symmetry, belongs to the tetragonal crystal system, and has a space group of MgHgGa4Se8. Its cell parameters are α = β = γ = 90°, Z = 1, and its volume is determined by the high-temperature melt method, chemical vapor transport method, or crucible lowering method. This crystal exhibits advantages such as significant nonlinear optical effects, good crystal growth habit, good mechanical properties, high hardness, resistance to breakage and deliquescence, and ease of processing and storage. It can be used to fabricate infrared nonlinear optical devices, which have important applications in optoelectronic warfare, laser communication, and medical fields.

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 provides a NiMoO4-coated NiSe2-PA core-shell nanowire electrocatalyst as well as a preparation method and application thereof, and belongs to the technical field of electrocatalytic materials. The preparation method comprises the following steps: dissolving a Mo source, a Ni source and urea in water, and then mixing with a Ni matrix for hydrothermal reaction to obtain a NiMoO4 precursor; taking the NiMoO4 precursor and selenium powder as raw materials, and preparing NiSe2-coated NiMoO4 by adopting a chemical vapor deposition method; the NiSe2 (at) NiMoO4 is subjected to a self-assembly reaction in a phytic acid solution, and the NiMoO4 (at) NiSe2-PA core-shell nanowire electrocatalyst is obtained. According to the electrocatalyst, the industrial-grade current density and the high-stability alkaline seawater OER performance are achieved, the problem of metal dissolution in the selenide electrooxidation process is solved, and a simple and effective strategy is provided for reasonably designing the high-activity and corrosion-resistant industrial-grade seawater electrolysis catalyst.

The invention provides a marine antifouling coating with an active-passive synergistic mechanism and a preparation method thereof.The preparation method comprises the steps that a porous template, ruthenium selenide and absolute ethyl alcohol are mixed and stirred to obtain a mixed solution, and the mixed solution is continuously heated to obtain mixed powder; placing the mixed powder and selenium powder in two crucibles respectively, and placing the crucibles in a tubular furnace for heating and calcining to obtain template-loaded ruthenium selenide; soaking the template-loaded ruthenium selenide in a concentrated alkali solution, heating to remove the porous template, and filtering, washing and drying after etching to obtain porous ruthenium selenide; the preparation method comprises the following steps: dissolving vinyl-terminated polydimethylsiloxane, a photoinitiator and polymercaptopropyl methyl siloxane in cyclohexane to obtain a coating base solution, adding porous ruthenium selenide into the coating base solution, uniformly stirring, carrying out ultrasonic treatment, and carrying out vacuum defoaming to obtain a coating solution; and coating the coating liquid on the surface of a base material, and curing after ultraviolet irradiation to obtain the marine antifouling coating with an active-passive synergistic mechanism.

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 invention discloses a preparation process of multi-metal doped phosphorus selenide. The preparation process comprises the following steps: step 1, preparing and mixing raw materials; 2, quartz tube pretreatment and raw material packaging; step 3, gradient calcination; the preparation method has the advantages that the composite metal phosphorus selenide (Fex (CoNiCuZn) 1-xPSe3) with gradient component distribution is prepared by regulating and controlling the molar ratio of Fe to Co, Ni to Cu to Zn (Fe: (Co + Ni + Cu + Zn) = 9: 1, 8: 2 and 7: 3) and combining a vacuum tube sealing high-temperature calcination process, the oxygen evolution reaction (OER) activity of the material is remarkably improved through the multi-metal synergistic effect and controllable lattice distortion optimization, and the composite metal phosphorus selenide can be used for preparing the composite metal phosphorus selenide (Fex (CoNiCuZn) 1-xPSe3) with gradient component distribution. The overpotential of the obtained catalyst under the current density of 10 mAcm <-2 > is as low as 322 mV and is close to commercial IrO2 (306 mV), the performance is excellent under the high current density of 100 mAcm <-2 >, the process is simple, the cost is low, the raw material cost is reduced by 90% or above compared with that of a noble metal catalyst, and a new strategy is provided for industrial application of the efficient OER catalyst.

The invention discloses a high-entropy sulfur selenide and preparation and application thereof, the high-entropy sulfur selenide is a Co9S8 compound doped with cations and anions, the doped cations are Fe, Ni, Mo and V, the doped anions are Se, each doped cation and anion are uniformly doped in Co9S8 crystal lattices, the molar ratio of Fe to Co to Ni to Mo to V is (8-11): 10: (8-11): (8-11): (8-11), and the molar ratio of S to Se is (5-15): 1. The invention provides application of the high-entropy sulfur selenide as a lithium ion battery negative electrode active material, and provides a lithium ion battery. According to the high-entropy sulfur selenide disclosed by the invention, the lithium ion battery can have excellent long cycle stability, high specific capacity and high-rate charge-discharge performance.

The present invention relates to the synthesis of pure metal or multi-metal derivatives of ZIF-11, ZIF-12 or amorphous ZIF structures in high yield followed by calcination under inert conditions to produce in composite nanostructures one or more metal selenide dispersed on the surface of or embedded in a carbon matrix, and using these composites as electrodes for lithium ion batteries, sodium ion batteries, potassium ion batteries, supercapacitors or fuel cells.

The invention belongs to the field of nano materials, and particularly relates to an indium selenide nanosheet compound as well as a preparation method and application thereof. The preparation method provided by the invention comprises the following steps: mixing indium selenide nanosheets and silver ions in a second solvent, so that silver nanoparticles grow on the surfaces of the indium selenide nanosheets; the second solvent is a polar solvent, the Hansen solubility parameter delta of the third solvent is greater than or equal to 18MPa < 1 / 2 >, and the mass ratio of the indium selenide nanosheets to the silver ions is (5-50): 1. And growing silver nano-silver particles on the surface of indium selenide by utilizing a spontaneous oxidation-reduction reaction of indium selenide and silver nitrate, so as to prepare the indium selenide nanosheet compound with the surface modified by the silver nano-silver particles. The silver nanoparticles have strong absorption, and the photoelectric response effect of the indium selenide nanosheet is remarkably improved by compounding the silver nanoparticles and the indium selenide nanosheet.

The invention belongs to the technical field of photocatalysts, and particularly relates to a sulfur nickel selenide cocatalyst, a photocatalyst and a preparation method and application of the sulfur nickel selenide cocatalyst, and the preparation method of the sulfur nickel selenide cocatalyst comprises the steps that a soluble nickel source, a soluble sulfur source and a soluble selenium source are dispersed in an alcohol solvent to be mixed, a reaction is conducted for 10-20 h at the temperature of 160-200 DEG C, and the sulfur nickel selenide is obtained after washing and drying; the molar ratio of the soluble nickel source to the soluble sulfur source to the soluble selenium source is 1: (0.5-1.5): (0.5-1.5). In the cocatalyst, Se is introduced into a NiS2 structure, lattice spacing is increased, a replacement solid solution NiSexS2-x is formed, in the solid solution, Se atoms replace S atoms in an atomic level and enter NiS2 lattices instead of being simply attached to the surface of NiS2 or forming heterojunctions, a single-phase and uniform crystal structure is formed instead of physically mixed two phases, and the structure is stable.

The application belongs to the technical fields of functional material preparation, catalysis and transition metal complex material, and discloses a selenium compound heterojunction catalyst coupled with hydrogen evolution, a method and application. In preparation, a cobalt source, urea, a foamed nickel and an ammonium fluoride mixed solution are mixed in a reaction, and after being hydrothermally synthesized and cooled to room temperature, the precursor Co(OH)2 / NF is obtained by washing with ethanol and water and drying. Then, selenium powder and a strong base are added into a reaction kettle, and heating is performed to obtain the heterojunction catalyst NiSe@CoSe2 / NF with high density. The obtained heterojunction material can be used for electrocatalysis of 5-hydroxymethylfurfural. When the current density is 10 mAcm ‑2 , the potential is 1.29 V, and the optimal conversion rate is more than 98%, and the catalyst has excellent catalytic activity for electrocatalysis of 5-hydroxymethylfurfural oxidation.

Described herein is two-dimensional (2D) indium selenide (InSe or In2Se3) with a combination of favorable attributes. Also described herein are methods of making and using the 2D InSe or In2Se3.

The application discloses a method for preparing gamma-valerolactone by catalyzing acetylpicoline acid hydrogenation with molybdenum selenide, and aims to solve the problems of low catalytic efficiency and harsh reaction conditions of existing non-noble metal catalyst systems. The method comprises the following steps: placing molybdenum selenide catalyst, acetylpicoline acid and a solvent as raw materials in a high-pressure reaction kettle, replacing the air in the high-pressure reaction kettle with hydrogen gas at room temperature for multiple times, then continuously feeding hydrogen gas until the pressure in the high-pressure reaction kettle reaches 0.5-3.0 MPa, magnetically stirring the reaction under the pressure range, at a temperature of 100-200 DEG C and in a hydrogen atmosphere, and then cooling to room temperature, so as to obtain gamma-valerolactone. The catalyst used in the application is prepared under hydrothermal conditions, and due to the sheet morphology of the molybdenum selenide catalyst, rich edge active sites are presented, so that the conversion rate of acetylpicoline acid and the selectivity of gamma-valerolactone can reach 100% under mild reaction conditions.

The invention discloses a noble metal nanocluster modified 1T phase catalyst and a preparation method and application thereof, the preparation method comprises the following steps: mixing a transition metal doped sheet 1T phase and / or 1T'phase substrate material with a noble metal salt solution, stirring for reaction, and then carrying out solid-liquid separation and washing to obtain the noble metal nanocluster modified 1T phase catalyst, by limiting the phase shape and morphology of the substrate material and doping the transition metal, the activity of the substrate material is regulated and controlled, the reaction rate of precious metal ions and sulfide or selenide and the like is increased, and the yield of the substrate material is increased under the condition that no medicament is added. And the noble metal nanocluster catalyst with high dispersion, high load and high uniformity can be rapidly prepared at room temperature by a one-step method.

This invention discloses a modified separator for lithium-sulfur batteries, its preparation method, and its application. The modified separator comprises a base film and a modified layer disposed on one side of the base film. The modified layer comprises a dual rare-earth metal selenide-boron-nitrogen co-doped functionalized carbon nanotube hybrid material. The preparation method is as follows: S1, functionalized carbon nanotubes, a boron source, a nitrogen source, and a solvent are mixed, and then ultrasonically dispersed and stirred until the boron and nitrogen sources are completely dissolved to obtain a carbon nanotube solution; a selenium source, a reducing agent, and a nucleating agent are mixed to obtain a mixed solution; S2, the carbon nanotube solution is mixed with the mixed solution, cerium salt, and lanthanum salt, and a solvothermal reaction is performed. The solid is then separated to obtain the hybrid material. This invention, by modifying the separator towards the sulfur cathode with a specific hybrid material, provides a large number of adsorption sites and effectively anchors and catalyzes the conversion of lithium polysulfides, effectively improving the deposition kinetics of Li2S and increasing sulfur utilization, thereby enhancing the long-cycle stability of lithium-sulfur batteries.

This application relates to the field of electrolyte materials technology, and in particular to a method for preparing lithium selenide. The method includes: obtaining a precursor source, the precursor source including lithium nitride and a selenium source, and subjecting the precursor source to multiple calcination treatments to obtain lithium selenide. The present invention uses lithium nitride as a lithium source and a selenium source to undergo a redox reaction to generate lithium selenide and nitrogen gas. This method has a low cost, does not produce carbon impurities in the prepared product, and the prepared lithium selenide can be used directly as a high-purity raw material for solid electrolytes. In addition, the reaction between lithium nitride and selenium has low exothermic reaction, the reaction is easy to control, and the safety is higher, avoiding the problem of low safety caused by high exothermic reaction of elemental selenium and elemental lithium in the prior art.

The invention belongs to the technical field of organic synthetic chemistry, and particularly relates to a preparation method and medical application of a visible-light-driven bis (trifluoromethyl) selenide compound. The preparation method of the bis (trifluoromethyl) selenide compound comprises the following steps: by taking olefin, trifluoromethylselenotetramethylammonium and bis (trifluoromethylseleno) diselenide as reaction raw materials, stirring and reacting under the conditions of proper temperature and visible light irradiation in the presence of cuprous salt to obtain the bis (trifluoromethyl) selenide compound. The method has the advantages of mild reaction conditions, simplicity and convenience in operation, good functional group compatibility and the like. In addition, the bis (trifluoromethyl) selenide compound provided by the invention shows good potential in the aspect of anticonvulsion, and has the prospect of being further developed into anticonvulsion drugs.

The invention discloses chromium-doped iron selenide and a preparation method and application thereof.The preparation method comprises the steps that organic mercaptan for dissolving selenium is injected into an organic amine solution for dissolving an iron source, and reaction is conducted in the inert gas atmosphere; and adding a chromium source, continuously reacting, and collecting a solid product after the reaction is finished. The three-dimensional'urchin-like 'chromium-doped iron selenide microspheres are synthesized by utilizing a heteroatom doping strategy, and a sample is subjected to electrochemical catalysis application. The electronic structure of the FeSe2 catalyst is effectively adjusted by doping the chromium atoms, so that the material generates lattice distortion, more active sites are exposed, and the catalytic efficiency of the FeSe2 catalyst is improved; the microspheres are formed by assembling one-dimensional nanorods with uniform sizes, have a relatively large specific surface area and are beneficial to rapid diffusion of an electrolyte and smooth escape of bubbles, so that the microspheres have excellent electro-catalytic water decomposition performance. The preparation steps are simple, and the method has the characteristics of short synthesis time, uniform morphology, high flexibility and the like.

This invention belongs to the fields of organic chemical synthesis technology and pharmaceutical synthesis technology, specifically relating to an α-arylselenium compound, its synthesis method, and its application. The preparation method includes the following steps: 1) using sulfone-thioylide compound and selenophenol as raw materials, adding them to a solvent, and stirring at 10-30℃ to obtain a reaction solution; 2) reacting the reaction solution at 10-30℃ to obtain the α-arylselenium compound.

This invention belongs to the field of composite electrode materials technology, and relates to a method for preparing a NiCoCu selenide composite MXene / carbon sphere thin film electrode material, comprising: first, dissolving ZIF-67 powder in a carbon sphere solution, then adding an MXene aqueous solution, stirring for 1-10 hours, filtering and drying to obtain ZIF-67@MXene / CS; second, preparing a solution according to the proportion of urea, copper source, nickel source and ethanol, immersing ZIF-67@MXene / CS, and reacting hydrothermally to obtain a NiCoCu-LDH@MXene / CS thin film; third, mixing the NiCoCu-LDH@MXene / CS thin film, selenium powder and sodium borohydride in a mass ratio of 0.5-1:1-2:1-2, reacting at 150-180°C for 12-24 hours, washing the obtained product with deionized water and drying to obtain the final product. MXene and carbon spheres together provide a flexible substrate for the self-supporting material, increasing its conductivity and specific surface area. Simultaneously, NiCoCu-Se intercalation into the MXene acts as an intermediate buffer, preventing MXene self-stabilization and making its structure more stable. When applied as the positive electrode material for supercapacitors, the self-supporting material avoids the use of binders, reducing the material's impedance and improving electrochemical performance.

According to the manganese selenide-carbon nanotube composite porous carbon material and the preparation method thereof provided by the invention, carbon nanotubes with excellent conductivity, nano selenium powder, manganese salt and polyvinylpyrrolidone are used as reaction raw materials, selenylation and carbonization are completed in one step through temperature programming, the reaction process is shortened, and the yield is increased. According to the preparation method, the production cost is reduced, the economic and time cost of production is reduced, the problems that various chemical reagents need to be added and the preparation process is complex in the current preparation process of the negative electrode material are solved, and the adopted preparation method is free of pollutant emission, conforms to the green chemistry principle and is beneficial to environmental protection.

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.