185results about "Binary selenium/tellurium compounds" patented technology

The invention relates to a vacancy-assisted tin heterovalent doped bismuth selenide material as well as a preparation method and application thereof, Se vacancy defects existing in VSe-Bi2Se3 are utilized to assist in stable doping of Sn < 4 + > into Bi sites, so that the Sn-VSe-Bi2Se3 material is obtained. As the positive electrode material of the zinc ion battery, the Sn-VSe-Bi2Se3 shows high specific capacity, excellent rate capability and long-acting stable cycle performance, and has the advantages of simple and convenient process, mild conditions and suitability for large-scale production.

The invention discloses a nickel-cobalt-selenium (Co1-xNixSe2) nano material for electrocatalytic oxidation of ethylene glycol as well as a preparation method and application of the nickel-cobalt-selenium (Co1-xNixSe2) nano material. The material is prepared by a hydrothermal method which comprises the following steps: (1) pouring 20mL of deionized water containing 475.9 mg of CoCl2. 6H2O into a 1mol / L NaOH solution containing 0.32 g of selenium powder to prepare a precursor solution; (2) placing in a stainless steel autoclave with a polytetrafluoroethylene lining, carrying out hydrothermal reaction at 180 DEG C for 18 hours, washing with absolute ethyl alcohol and deionized water, and carrying out vacuum drying at 60 DEG C to obtain a CoSe2 material; and (3) the molar feeding ratio of CoCl2. 6H2O to NiCl2. 6H2O is adjusted, so that the nickel / cobalt ratio x is 0.25, 0.50 or 0.75, and materials with different components, namely Co < 0.75 > Ni < 0.25 > Se < 2 >, Co < 0.50 > Ni < 0.50 > Se < 2 > and Co < 0.25 > Ni < 0.75 > Se < 2 >, are prepared. The series of materials are applied to ethylene glycol oxidation under the alkaline condition, the catalytic performance of Co < 0.50 > Ni < 0.50 > Se < 2 > is optimal, the current density reaches 111 mA cm <-2 > under the electric potential of 1.6 V vs.RHE, the total Faraday efficiency reaches up to 91.4%, and the application prospect in the field of PET plastic recovery is wide.

The invention relates to the technical field of preparation of electro-catalysis electrode materials, in particular to a preparation method and application of a SeO2 doped RuO2 electrolyzed water catalyst.The preparation method comprises the steps that S1, ruthenium acetate and selenium dioxide are dissolved in deionized water together and continuously stirred to obtain a mixed solution A, then sodium citrate is dissolved in deionized water, and the PH value is adjusted to be 9 with ammonia water to obtain a solution B; s2, mixing the solution A and the solution B, reacting at 80 DEG C for 12 hours, naturally cooling, ultrasonically washing with deionized water and ethanol in sequence, centrifuging, and drying in a drying oven to obtain a catalyst precursor; and S3, carrying out two-step pyrolysis on the precursor, namely heating to 250 DEG C, annealing for 4 hours, heating to 400 DEG C, annealing and heating for 2 hours, so as to obtain the SeO2-doped RuO2 nanosheet. By introducing a proper amount of SeO2 for doping, the electronic structure of RuO2 is optimized, the adsorption and desorption balance effect of the catalyst on a reaction intermediate is adjusted, the Ru site catalytic performance is improved, and the obtained SeO2-doped RuO2 nanosheet has efficient acidic OER catalytic 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 provides a preparation method of a Mo-doped FeSe2 electrode material and application of the Mo-doped FeSe2 electrode material as a sodium-ion battery anode, and the preparation method comprises the following steps: mixing FeCl3. 6H2O, terephthalic acid and N, N-dimethylformamide, loading into a reaction kettle, and heating at high temperature to obtain an MIL-88B metal organic framework precursor; and then dispersing the MIL-88B precursor, sodium molybdate, selenium powder and hydrazine hydrate in a solvent, and doping Mo atoms into a FeSe2 electrode material through hydrothermal synthesis to obtain the Mo-FeSe2 sodium ion battery anode. According to the preparation method, Mo atoms are doped into FeSe2, so that the strength of Fe-Se bonds is enhanced, the structure collapse effect of the electrode material is effectively relieved from the structure level, an SEI film on an electrode liquid interface is compact and uniform, and the multiplying power and the cycle service life of the electrode material are effectively improved.

The utility model relates to a device for producing tellurium powder by using tellurium dioxide, and belongs to the technical field of tellurium powder production equipment. Comprising a leaching kettle, a plate-and-frame filter press, a primary reduction kettle, a primary reduction filter barrel, a secondary reduction kettle, a secondary reduction filter barrel and a waste liquid tank which are sequentially connected, materials in the leaching kettle are conveyed into the plate-and-frame filter press through a first conveying pump, and the leaching kettle is further connected with a hydrochloric acid storage tank through a pipeline; the opening of the primary reduction kettle is positioned right above the primary reduction filter barrel, and the primary reduction kettle is also connected with a sulfur dioxide steel cylinder; materials in the primary reduction filter barrel are conveyed into a secondary reduction kettle through a second conveying pump; an outlet of the secondary reduction kettle is positioned right above the secondary reduction filter barrel, and the secondary reduction kettle is also connected with a sulfur dioxide steel cylinder; materials of the secondary reduction filter barrel are input into the waste liquid tank through a third conveying pump; the tellurium dioxide is produced by adopting the method, the technological operation is simple, the production efficiency is high, the tellurium content of the liquid after secondary reduction is low, the liquid can be reused in a leaching kettle, and the use amount of hydrochloric acid is reduced.

The invention discloses a preparation method of a NiS / NiSe2 heterojunction containing a non-interface Ni vacancy. The preparation method comprises the steps of precursor preparation and in-situ selenylation treatment. The invention further discloses the NiS / NiSe2 heterojunction containing the non-interface Ni vacancy. The NiS / NiSe2 heterojunction containing the non-interface Ni vacancy is prepared through the method.

The invention belongs to the technical field of nano materials and anti-tumor treatment medicines, and discloses cordyceps sinensis mycelium polysaccharide-copper selenide with dual effects of inducing tumor cell apoptosis and copper death as well as a preparation method and application thereof. The preparation method of the cordyceps sinensis mycelium polysaccharide-copper selenide comprises the following steps: taking cordyceps sinensis mycelium polysaccharide as a template, adopting a soft template method, reducing Na2SeO3 through Vc, and adding CuSO4 to prepare the cordyceps sinensis mycelium polysaccharide-copper selenide. The cordyceps sinensis mycelium polysaccharide-copper selenide can selectively kill tumor cells and induce apoptosis and copper death of the tumor cells at the same time, and has huge application potential in the aspect of tumor prevention and treatment.

The invention belongs to the technical field of sodium-ion batteries, and particularly relates to an iron-manganese-based sodium-ion battery positive electrode material as well as a preparation method and application thereof. The preparation method of the iron-manganese-based sodium ion battery positive electrode material comprises the following steps: adding ferric nitrate and manganese nitrate into water for dissolving, performing spray pyrolysis to obtain an iron-manganese oxide precursor, performing ball-milling mixing on sodium carbonate, the iron-manganese oxide precursor and lanthanum telluride, and calcining in an inert gas atmosphere to obtain a composite material; and adding Ni4O4 cubic alkane modified carbazole, the composite material and manganese dioxide into dilute sulphuric acid for ultrasonic dispersion, stirring for reaction, centrifuging, washing and drying to obtain the iron-manganese-based sodium ion positive electrode material. The iron-manganese-based sodium ion battery positive electrode material provided by the invention has the advantages of stable rate cycle, high specific capacity and excellent capacity retention rate.

The application discloses a transfer method of a two-dimensional material film, which comprises the following steps: coating photoresist on the surface of a two-dimensional material film directly grown on a growth substrate and solidifying the photoresist to form a transfer medium layer; separating the growth substrate from the transfer medium layer / two-dimensional material film; after the transfer medium layer / two-dimensional material film is attached to a target substrate, heating is performed to melt the transfer medium layer; and the transfer medium layer is removed. The transfer method of the application utilizes the characteristic that the photoresist can be softened at a low melting point after being solidified, and firstly solidifies the photoresist on the surface of the two-dimensional material film to be transferred to serve as a support medium for the transfer of the film, so that the transfer of the film is realized. After being transferred to the target substrate, the solidified photoresist can be softened, so that the transferred two-dimensional material film can be fully contacted with the target substrate, and the complete and intact transfer of the two-dimensional material film can be realized. The transfer method of the application is especially suitable for the transfer to a rough target substrate.

The invention discloses an electrochemical method for regulating and controlling the phase, resistance and magnetism of a two-dimensional layered material, and belongs to the field of two-dimensional transition metal chalcogenide. The electrochemical method comprises the steps that an electrode system is provided, the electrode system comprises a working electrode and a counter electrode, the working electrode comprises a two-dimensional layered material, the chemical formula of the two-dimensional layered material is MX2, M represents a transition metal element, and X represents a group VI element where a sulfur element is located; providing an electrolyte, wherein the electrolyte is a soluble salt solution containing magnetic transition metal ions; the electrode system is placed in the electrolyte, and under the action of an external electric field, the magnetic transition metal ions are embedded and separated from the two-dimensional layered material, so that the phase, the resistance and the magnetism of the two-dimensional layered material are synergistically regulated and controlled. According to the technology, magnetic transition metal ions are driven by an electric field to be reversibly embedded into and separated from a two-dimensional layered material, so that the phase, the resistance and the magnetism of the two-dimensional layered material are synergistically and dynamically regulated and controlled, and the problems that the traditional external field regulation and control dimension is single, and intrinsic physical property coupling change is difficult to realize are solved. And multi-physical-property combined regulation and control is realized by adjusting an electric field, so that a basis is provided for application of the material in the fields of photoelectric devices, magnetoelectric storage, sensors and the like.

The application relates to the field of surface-enhanced Raman scattering, and specifically provides a three-dimensional SnSe2 surface-enhanced Raman scattering substrate and a preparation method thereof. The three-dimensional SnSe2 surface-enhanced Raman scattering substrate comprises a filter layer, a plurality of filter holes are arranged on the filter layer, a SnSe2 nanostructure layer is fixedly arranged on the upper side of the filter layer, the SnSe2 nanostructure layer is composed of SnSe2 nanostructures, the SnSe2 nanostructure is SnSe2 nanoflower, the SnSe2 nanoflower covers the filter layer, and the SnSe2 nanoflower blocks the filter holes on the filter layer. No vertical gap exists in the SnSe2 nanoflower structure, which makes the local effect of the SnSe2 nanoflower on a light field better, so that the Raman signal enhancement factor is improved. The preparation method of the three-dimensional SnSe2 surface-enhanced Raman scattering substrate comprises the following steps: S1, preparing SnSe2 nanoflower; S2, preparing an aqueous solution of the SnSe2 nanoflower; and S3, performing suction filtration to obtain the SnSe2 surface-enhanced Raman scattering substrate. The preparation method does not use a molecular beam epitaxy method, and the cost is low.

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 application discloses a preparation method of a suspended two-dimensional material film and the suspended two-dimensional material film. The preparation method comprises the following steps: providing a substrate, wherein the substrate has a first surface and a second surface opposite to each other; forming a sacrificial layer film on the first surface of the substrate; forming a through hole on the second surface of the substrate, and the through hole exposes the sacrificial layer film; obtaining a two-dimensional material film, transferring the two-dimensional material film to the sacrificial layer film, and the two-dimensional material film covers the through hole; etching the sacrificial layer film from the second surface of the substrate until the two-dimensional material film is exposed, and a suspended two-dimensional material film is formed. The preparation method of the suspended two-dimensional material film and the suspended two-dimensional material film have the advantages that the two-dimensional material film has low transfer difficulty, the light source has little influence on the test, and the test means is effectively widened.

The invention discloses a carbon nanotube / cadmium selenide quantum dot heterojunction photoelectric catalyst as well as a preparation method and application thereof. The method comprises the following steps: activating single-wall and / or multi-wall carbon nanotubes by aqua regia at room temperature, dispersing the single-wall and / or multi-wall carbon nanotubes in an aqueous solution containing CdCl2. 5H2O, adding a Na2SeSO3 selenium source and 3-mercaptopropionic acid, and reacting at 110-150 DEG C, so that CdSe quantum dots with the particle size of 1-5 nm are subjected to in-situ nucleation growth on the surfaces and / or the interiors of the carbon nanotubes and form a heterojunction interface. The obtained catalyst and Nafion are prepared into ink drops, the ink drops are coated on conductive glass to construct a photocathode, in an H-type electrolytic tank with a light path, a high-purity CO2 saturated bicarbonate aqueous solution is used as an electrolyte, Ag / AgCl is used as a reference electrode, and under irradiation of an LED light source with the maximum wavelength being 450 nm and bias voltage ranging from-0.1 V (vs. RHE) to-1.0 V (vs. RHE), CO is generated through water-phase photoelectrocatalysis CO2 reduction. The photoelectrocatalyst has the characteristics of simple synthesis method and excellent photoelectrocatalytic reduction effect of carbon dioxide.

A method for producing a chalcogen-containing compound semiconductor is provided, the method comprising: providing a processing chamber (3) with at least one substrate (5) coated with a precursor (4) of the chalcogen-containing compound semiconductor; heat-treating the at least one coated substrate (5) in the processing chamber (3), wherein during the heat treatment, a gaseous atmosphere containing at least one gaseous chalcogen compound is provided in the processing chamber (3); removing the gaseous atmosphere present after the heat treatment of the coated substrate (5) as exhaust gas from the processing chamber (3); and cooling the exhaust gas in a gas processor (13), wherein multiple types of gaseous chalcogen compounds present in the exhaust gas after the heat treatment of the coated substrate (5) are converted to liquid or solid states, thereby separating them from each other in time and space from the exhaust gas. An apparatus designed to carry out this method is also provided.

This invention belongs to the field of battery energy storage technology, and more specifically relates to a low-cost, low-temperature, ambient-pressure synthesis method for CuSe and its application in sodium-ion batteries. The invention uses copper and selenium sources as reactants, an acid solution as a promoter, and ethanol as a dispersant, and synthesizes the CuSe material via a wet process at ambient pressure and low temperature. The preparation method is simple and does not involve high temperature, high pressure, or toxic reagents, which are detrimental to practical applications. When used in sodium-ion batteries, it exhibits excellent cycle performance and rate capability.

The present invention relates to a quantum dot synthesis method for synthesizing chalcopyrite-based quantum dots, the quantum dot synthesis method comprising: a nanoparticle production step for reacting a group I element and a group VI element to produce nanoparticles; and a cation diffusion step for diffusing group III element cations into the nanoparticles by heat treatment. Accordingly, there is provided a method for synthesizing quantum dots having good light-emitting characteristics having uniform particle diameters but not having compositional inhomogeneity.

A quantum dot having a narrow fluorescence half-width and a high fluorescence quantum yield has a core-shell structure including a core formed from ZnSe or ZnSeTe, and a shell that covers the core and is formed from ZnS, wherein a particle diameter of the quantum dot is 5 nm or more and 20 nm or less, and wherein a surface of the core-shell structure is modified with a zinc halide. The quantum dot has a fluorescence quantum yield of 75% or more and a fluorescence half-width of 25 nm or less. The fluorescence lifetime can be made 50 ns or less.

The present application belongs to the field of metallurgy, and relates to a method for producing antimony white by directly oxidizing crude antimony, comprising the following steps: S1, mixing crude antimony with crude antimony alloy, and reacting under an oxygen-containing atmosphere, to obtain oxidized slag and a melt after the reaction is completed; S2, adjusting the temperature of the melt, and then introducing compressed air to react, to produce antimony trioxide-containing flue gas, and to obtain antimony oxide slag after the reaction is completed. The present application makes full use of impurities such as sodium sulfide, sodium hydroxide and sodium thiosulfate contained in crude antimony, and innovatively uses these components for arsenic removal reaction, which not only avoids the cumbersome steps of adding various auxiliary materials in the traditional process, but also enables the original sodium sulfide, sodium hydroxide and sodium thiosulfate in the crude antimony to fully play a synergistic role, showing excellent performance in arsenic removal effect, thus simplifying the process flow, significantly reducing the production cost, and realizing the dual improvement of economic benefit and process efficiency.

An object is to provide a quantum dot that has a narrow fluorescence half-width and a high fluorescence quantum yield, and emits blue fluorescence. A quantum dot (5) according to the present invention includes at least Zn and Se and does not include Cd, and has a particle diameter of 5 nm or more and 20 nm or less. In addition, the quantum dot (5) according to the present invention includes at least Zn and Se and does not include Cd, and has a fluorescence quantum yield of 58 or more and a fluorescence half-width of 25 nm or less. In the present invention, the fluorescence lifetime can be made 50 ns or less.

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.

The preparation of high-value-added aromatic carboxylic acids via CO2 carboxylation coupling through activation of the benzyl C-H bond in alcohols / amines is a green and sustainable pathway to achieve CO2 resource utilization and contribute to carbon neutrality. However, this field currently faces challenges such as poor catalyst selectivity, low CO2 activation efficiency, and a narrow substrate applicability range, making it difficult to meet practical application needs. To address this issue, this patent discovers that in a heterogeneous electrocatalytic system, cuprous selenide (V2), rich in selenium vacancies, can be used... Se -Cu 2‑x Using Se as the core catalyst, it can not only efficiently promote the synergistic activation of benzyl C-H bonds and CO2 carboxylation, significantly improving the overall catalytic activity of the reaction, but also achieve precise chemoselective carboxylation control for different types of substrates. Specifically, this V Se -Cu 2‑x Se electrocatalysts can efficiently and selectively activate the benzyl C-H bond in alcohols and subsequently induce CO2 carboxylation, exhibiting excellent chemoselectivity in the conversion of benzyl alcohol to mandelic acid and its derivatives. Simultaneously, they also demonstrate excellent catalytic performance for amines, selectively catalyzing the carboxylation of amine substrates such as benzylamine with CO2 to directionally generate phenylglycine and aromatic amine-derived carboxylates. Crucially, in addition to typical benzyl alcohol and benzylamine, the substrate applicability of this catalytic system can be extended to various alcohols and amine derivatives, realizing the carboxylation transformation from simple model substrates to diverse functional molecules, providing a new approach for the large-scale preparation of high-value-added aromatic carboxylates.

The invention relates to the technical field of preparation of high-purity inorganic nano materials, and discloses a controllable preparation method of a high-purity cadmium telluride nanocrystal, which comprises the following steps: pre-dissolving a conjugated acid salt in a water-phase reaction system, and reacting a cadmium salt precursor with a tellurium source precursor when ammonia gas is introduced as an inorganic gaseous ligand; a pH buffer system is constructed by ammonia gas and conjugated acid salt, and transient stability is provided for the generated cadmium telluride nanocrystals within the pH range for inhibiting the cadmium hydroxide impure phase; according to the method disclosed by the invention, an in-situ pH buffer system is constructed, so that a ligand stabilization function of the ammonia gas is decoupled from an alkaline side reaction phase of the ammonia gas, agglomeration is prevented while an impure phase is inhibited, the ligand and the salt are thoroughly removed after the reaction, and the technical problem that controllability and high purity cannot be obtained at the same time in an inorganic aqueous phase method is solved.

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 relates to a high-crystallization mercury-based II-VI group nanocrystal synthesis method based on an octadecene-amine mixed solvent. The method comprises the following steps: providing a mercury-containing compound as a mercury source; providing a precursor solution capable of releasing II-VI group element anions; octadecene and an amine-containing surfactant are mixed in proportion to serve as a reaction solvent; injecting the precursor solution into a reaction solvent containing a mercury source in an inert atmosphere, and reacting under the condition that the temperature is lower than the thermal injection temperature to generate the mercury-based II-VI group nanocrystal with small size and higher crystal quality; and cooling and purifying the reaction product to obtain the target nanocrystal. By mixing the non-polar solvent and the amine surfactant, the concentration of the surfactant is reduced, the growth rate of the crystal is slowed down, the low-temperature controllable reaction is realized, the nanocrystal of which the particle size is 2-5nm and the crystal quality is remarkably improved is obtained, and the half-peak width of an X-ray diffraction pattern can be less than 0.7 degree (2 theta). The problems that the crystal size is difficult to control and the crystal quality is insufficient in a traditional method are solved.

The invention relates to the technical field of nano composite material preparation, and discloses preparation and application of a ZnSe / covalent triazine framework CTF layered composite material, and the preparation method comprises the following steps: firstly, obtaining a CTF nanosheet through a molten salt auxiliary heating polymerization method, then preparing ZnSe nano particles through a solvothermal method, and finally preparing the ZnSe / covalent triazine framework CTF layered composite material. And finally, the ZnSe / covalent triazine skeleton CTF layered composite material is obtained by adopting an ultrasonic and normal-temperature stirring induced interface self-assembly strategy. The ZnSe nano-particles are innovatively assembled on the CTF nano-sheet, so that the ZnSe nano-particles are uniformly loaded on the surface of the CTF nano-sheet, a tight contact interface is formed, and active sites and specific surface area of reaction are increased; meanwhile, the photoresponse range of the composite material is obviously increased, and the light energy utilization rate is increased, so that the ZnSe / covalent triazine skeleton CTF layered composite material has better solar energy conversion activity and wide industrial application prospect.

Methods, systems, and devices for chalcogenide memory device compositions are described. A memory cell may use a chalcogenide material having a composition as described herein as a storage materials, a selector materials, or as a self-selecting storage material. A chalcogenide material as described herein may include a sulfurous component, which may be completely sulfur (S) or may be a combination of sulfur and one or more other elements, such as selenium (Se). In addition to the sulfurous component, the chalcogenide material may further include one or more other elements, such as germanium (Ge), at least one Group-III element, or arsenic (As).

The invention discloses an erbium-doped zinc selenide composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving zinc nitrate hexahydrate and erbium nitrate hexahydrate in deionized water, wherein the molar ratio of erbium ions in the zinc nitrate hexahydrate is 0.02-0.08; adding sodium selenite and sodium hydroxide; adding a reducing agent hydrazine hydrate; after hydrothermal reaction for h, washing and drying to obtain the erbium-doped zinc selenide composite material. The material is of a cubic phase ZnSe structure, erbium is uniformly doped in crystal lattices, and the material is in a nearly spherical particle shape. Rich 4f electronic defect states are introduced into a ZnSe band gap through erbium doping, charge transfer (chemical enhancement) is remarkably promoted, the free carrier concentration is improved to excite localized surface plasma resonance (electromagnetic enhancement), and the synergistic effect of two enhancement mechanisms is achieved. The detection limit of the SERS substrate to methylene blue is as low as 3.24 * 10 <-8 > mol / L, the enhancement factor is as high as 1.73 * 10 < 4 >, and a new way is provided for environmental pollutant monitoring.

The application discloses a preparation method and application of a carbon nanotube-wrapped S-doped Se-vacancy type NiSe2 electrocatalyst, and belongs to the technical field of catalytic materials. The electrocatalyst material is prepared by adopting a hydrothermal-solid phase heat treatment combined method, and the steps include the following: firstly, a carbon nanotube-loaded Ni(OH)2 nanosheet precursor is prepared by adopting a hydrothermal reaction; then, a carbon nanotube-wrapped S-doped NiSe2 electrocatalyst is obtained through a hydrothermal reaction; and finally, the electrocatalyst is heat-treated in an inert atmosphere, so that Se vacancies are introduced. The carbon nanotube-wrapped S-doped NiSe2 electrocatalyst with rich Se vacancies is designed and prepared by adopting a two-in-one strategy. The staggered carbon nanotubes provide an integrated conductive network, and the introduction of S atoms and Se vacancies improves the oxygen evolution reaction activity of the electrocatalyst, so that the electrocatalyst has a wide application prospect in the fields of water electrolysis and metal-air batteries.