14results about How to "Many surface active sites" patented technology

The invention belongs to the field of waste liquid recycling, and discloses a method for preparing potassium fluosilicate by using mixed waste acid, which comprises the following steps: S1, silica fume acidification pretreatment: soaking silica fume in an acid solution for acidification, carrying out precipitation separation on the silica fume, drying, and grinding to obtain acidified silica fume; s2, mixing the raw materials: uniformly mixing the acidified silica fume and the silicon dioxide powder; s3, preparation of fluosilicic acid: adding a mixture of acidified silica fume and silicon dioxide powder into the mixed waste acid, and uniformly stirring by a mechanical stirrer; and S4, preparation of potassium fluosilicate: adding a potassium chloride saturated solution into the fluosilicic acid solution to generate potassium fluosilicate precipitate. The method has the advantages and effects of being high in fluorine ion utilization efficiency, low in production cost and high in finished product purity.

This invention discloses a chemiluminescence gas sensor based on polyoxometalates (POMs), and relates to its fabrication method and application. The sensor is suitable for detecting ammonia at room temperature. The gas sensor includes an adapter base and a sensing element, wherein the sensing element consists of interdigitated electrodes and a sensitive material loaded on the electrode surface. This sensitive material is a composite material of POMs and SnO2. POMs, as excellent electron acceptors, possess good redox properties, thermal stability, and photosensitivity. When combined with SnO2, they can effectively suppress electron-hole recombination, thereby significantly improving the gas-sensing performance of the semiconductor material. Compared with existing technologies, the sensor provided by this invention exhibits high response characteristics to ammonia at room temperature, while also demonstrating excellent selectivity and repeatability.

The invention relates to the technical field of lithium ion batteries, in particular to a nickel positive electrode material, a preparation method and application. The preparation method of the nickel positive electrode material comprises the following steps: mixing soluble nickel salt, cobalt salt and manganese salt according to a target stoichiometric ratio to obtain a mixed salt solution, and adding a niobium source or a tungsten source into the mixed salt solution to obtain a first solution; meanwhile, preparing a sodium hydroxide solution with a certain concentration as a precipitator and ammonia water with a certain concentration as a complexing agent; under the conditions of continuous stirring and controllable temperature, the first solution, a sodium hydroxide solution and ammonia water are added into a reactor in a parallel flow mode, metal ions are co-precipitated by adjusting the pH value, the reaction temperature, the ammonium radical concentration and the rotating speed, and a nickel-cobalt-manganese-niobium hydroxide precursor or a nickel-cobalt-manganese-tungsten hydroxide precursor is obtained after aging, filtering, washing and drying; and uniformly mixing the nickel-cobalt-manganese-niobium hydroxide precursor or the nickel-cobalt-manganese-tungsten hydroxide precursor with a lithium source, and roasting to obtain the nickel positive electrode material. And the performance of the lithium ion battery can be improved.

The invention belongs to the field of lithium-sulfur secondary batteries, and relates to a high-performance lithium-sulfur battery, the high-performance lithium-sulfur battery comprises a sulfur-carbon positive electrode, a lithium negative electrode, an electrolyte and a diaphragm, the diaphragm comprises a base membrane and a functional coating coated on one or two surfaces of the base membrane, and the functional coating comprises molybdenum disulfide particles coated with metal molybdenum nanoparticles. The application of molybdenum disulfide particles coated with metal molybdenum nanoparticles to the functional layer of the lithium-sulfur battery diaphragm is proposed for the first time, so that the shuttle effect of polysulfide can be effectively inhibited, the redox reaction of the polysulfide can be accelerated, the polysulfide is promoted to be quickly converted into solid Li2S, the utilization rate of sulfur is increased, the accumulation of intermediate products is reduced, and the service life of the lithium-sulfur battery diaphragm is prolonged. The coulombic efficiency and the cycling stability of the battery are improved; and the two are combined to form an efficient conductive network, so that the conductivity is remarkably improved, rapid transmission of electrons in the conductive network is promoted, and the rate capability of the battery is improved.

The application discloses a cellulose cross-linked carbon sponge / MXene composite material and a preparation method and application thereof, and belongs to the technical field of noble metal resource recovery and functional adsorption materials. x MXene nanosheets are used as a functional component, and cellulose nanofilaments are introduced as an interface cross-linking agent. The composite material utilizes the synergistic effect of nitrogen coordination sites in the CMS and low-valence titanium active sites in the MXene, realizes efficient adsorption and in-situ reduction of Au(III), exhibits good selectivity for Au(III) in a complex multi-ion system, and is suitable for the recovery of noble metal ions in a complex system such as electronic waste leaching liquid.

The application relates to the technical field of sensors, in particular to a zinc metatungstate composite material and a preparation method and application thereof. The composite material is a zinc metatungstate composite material doped with Bi2O3 and Sb2O3, the specific surface area of the composite material is large, the surface active sites are many, and the pore structure is rich, the composite material has high responsiveness to VOCs gas as a gas-sensitive material, and the stability is good.

The invention relates to the technical field of oxygen evolution catalysts, in particular to a vanadium-based high-entropy alloy catalyst and a preparation method and application thereof. The vanadium-based high-entropy alloy catalyst is composed of a high-entropy alloy component and a carbon component coating the surface of the high-entropy alloy component, the high-entropy alloy component is Fe, Co, Ni, Zn and V, and the microstructure of the high-entropy alloy component is of a spherical flower-shaped structure formed by polymerizing nanosheet layers; the preparation method of the vanadium-based high-entropy alloy catalyst sequentially comprises the following steps: preparing a metal salt mixed solution, an organic mixed solution, a metal organic framework precursor and the vanadium-based high-entropy alloy catalyst; the vanadium-based high-entropy alloy catalyst not only has high specific surface area and high content of surface functional groups, but also effectively reduces the reaction energy barrier of oxygen evolution reaction by introducing a V element into the catalyst to adjust the electronic structure of the high-entropy alloy, so that the overpotential of the catalyst is only 284mV at 10mA cm <-2 >, and the stable output time of the catalyst which does not present a decline trend is 45h; the catalyst is far better than the same catalyst.

This invention discloses a selenium / zinc oxide co-loaded biochar material, its preparation method, and its application. The preparation method includes the following steps: 1) calcining leaves under nitrogen protection at 350~750℃, then grinding and sieving to obtain biochar powder; 2) mixing and dispersing the obtained biochar powder, sodium selenite, and zinc salt at a mass ratio of 100:(0.1~5):(5~15), and then hydrothermally reacting at 100℃~180℃ for 8~12 h to obtain the selenium / zinc oxide co-loaded biochar material. This invention obtains biochar by calcining leaves, then mixing the biochar with sodium selenite, zinc salt, and other substances, followed by a hydrothermal reaction. This allows selenium and zinc to be simultaneously loaded onto the surface and pores of the biochar. The prepared selenium / zinc oxide co-loaded biochar has a porous structure and abundant surface active sites, which can uniformly anchor and synergistically distribute active selenium and zinc species, endowing the material with highly efficient synergistic antibacterial properties.

This invention belongs to the field of lithium battery technology, specifically relating to a PVDF-based composite solid electrolyte, its preparation method and application, and lithium batteries. The composite solid electrolyte comprises a PVDF-based polymer, lithium salt, amide substances, nano-metal oxides, and residual organic solvents. The nano-metal oxides and amide substances jointly regulate the solvation structure of lithium ions, weakening the interaction between the solvent and lithium ions. [Li (residual solvent)] x ] + The interaction forces with the polymer create a weak interaction environment for lithium ions, promoting the Li-polymerization process. + The process facilitates the transport of ions and simultaneously transforms the solvent-derived electrode-electrolyte interface phase into an anion-dominant derived phase, thereby improving interface stability. On the other hand, the nano-metal oxides reduce the crystallinity of the PVDF polymer, inhibit spherulite formation, and densify the electrolyte membrane. This contributes to the construction of uniform and continuous ion transport channels, improves mechanical properties, effectively suppresses the growth of lithium dendrites, and enhances the cycle stability of the battery.

The invention discloses a manganese dioxide-copper (II)-protein membrane composite material which is composed of a protein membrane and manganese dioxide and copper (II) loaded on the protein membrane, and a preparation method of the composite material comprises the following steps: placing the dried protein membrane in a potassium permanganate solution, adding a copper sulfate solution, reacting for 30-40 minutes, and loading MnO2 and copper (II) generated by the reaction on the protein membrane; and taking out and drying. The manganese dioxide-copper (II)-protein membrane composite material is applied to arsenic adsorption. The arsenic exists in the form of any one or more than two of As (III), As (V), monomethyl arsenic, dimethyl arsenic and arsenic betaine. The manganese dioxide-copper (II)-protein membrane composite material disclosed by the invention is simple and convenient to prepare and low in cost, and has a good adsorption effect on various forms of arsenic. The method disclosed by the invention is of great significance to removal of arsenic in water and euphausia superba oil.

The invention discloses a tungsten disulfide / tungsten trioxide nanoflower electrode and a preparation method and application thereof.The method comprises the steps that a sulfur source is added into an aqueous solution containing a tungsten source and mixed to be uniform, and a mixed solution is obtained; dropwise adding an auxiliary agent into the mixed solution, stirring in the dropwise adding process, and aerating the obtained solution in oxygen after dropwise adding to obtain a precursor solution; and pouring into a reaction kettle, immersing the pretreated carbon cloth into the solution in the reaction kettle, carrying out hydrothermal reaction, cleaning the reacted electrode, and drying to obtain the tungsten disulfide / tungsten trioxide nanoflower electrode. According to the invention, the difficult problem of coupling of hydrogen evolution reaction and carbon dioxide microbial electrosynthesis is solved. The hydrogen evolution rate of the material is controlled by controlling the synthesis temperature, so that the in-situ electrochemical hydrogen production rate of the electrode and the hydrogen consumption rate of microorganisms are balanced, and the high coulombic efficiency of the product acetic acid is obtained.

The present application belongs to the field of photoelectrode devices, and particularly relates to a method for regulating and converting defects in a photoelectrode device. The present application relates to obtaining a material with better carrier transfer capability using a simple synthesis method, and regulating defects of the modified photoanode to reduce the influence of adverse defects on the device and improve the surface OER performance. The present application selects zinc indium sulfide (named as ZIS) as a photoanode, uses a simple low-temperature water bath method, and obtains a Mg-doped ZIS photoanode device (named as ZIS:Mg) by performing Mg doping treatment on the ZIS. Then, the O defects caused by Mg doping are converted into Mg-O bonds by a simple nitrogen annealing method, and a ZIS:MA photoanode device is obtained.

The invention discloses a nitrogen-doped graphite phase carbon nitride nanosheet loaded optical fiber composite photocatalytic material as well as a preparation method and application thereof. The nitrogen-doped graphite phase carbon nitride nanosheet is composed of C and N elements, and the constituent elements are uniformly dispersed on the surface of the ultrathin mesoporous nitrogen-doped graphite phase carbon nitride nanosheet, so that the nanosheet has a higher specific surface area and more surface active sites. The prepared nitrogen-doped graphite-phase carbon nitride nanosheet is loaded on the light-guide fiber, so that harmful substances in wastewater can be degraded in a short time, the nanosheet can be repeatedly used for more than three times, and the nanosheet is simple to use, green and environment-friendly. The preparation method of the nitrogen-doped graphite-phase carbon nitride nanosheet or the method of loading the nitrogen-doped graphite-phase carbon nitride nanosheet on the light-guide fiber is simple to operate and wide in raw material source, and has certain practicability.

The invention provides a Fe-ZnO (at) Au-DTNB nano-label with an electronic structure regulated and controlled as well as a preparation method and application of the Fe-ZnO (at) Au-DTNB nano-label, and relates to the technical field of lateral flow immunoassay. The nano-label comprises iron-doped zinc oxide, and the iron-doped zinc oxide is loaded with gold nano-particles. The nano-label further comprises a Raman reporter molecule DNTB, one end of the Raman reporter molecule DNTB is connected with the gold nano-particles through an Au-S bond, and the other end of the Raman reporter molecule DNTB is coupled with the A-influenza-resistant labeled antibody through modified carboxyl. According to the preparation method, the electronic structure of ZnO is adjusted through iron doping, so that surface charges of Fe-ZnO (at) Au-DTNB are enriched; the surface hot spots and the SERS activity are enhanced, so that the excellent performance is given to the LFIA detection system based on the Fe-ZnO (at) Au-DTNB.