24 results about "Constant current density" patented technology

The invention belongs to the field of all-vanadium redox flow batteries, and particularly discloses a bismuth alkene nanosheet modified defect-rich graphite felt electrode for an all-vanadium redox flow battery and a preparation method of the bismuth alkene nanosheet modified defect-rich graphite felt electrode for the all-vanadium redox flow battery. The preparation method comprises the following steps: dissolving zinc nitrate (Zn (NO3) 2) in a solvent to prepare a saturated solution, soaking TGF in the saturated solution, drying, and calcining in a nitrogen atmosphere to prepare porous graphite felt (CGF) of which the surface is rich in carbon defects; the preparation method comprises the following steps: dissolving bismuth chloride (BiCl3) in a prefabricated electrolyte (containing V2 (SO4) 3 and H2SO4 solution with a certain concentration), and depositing on the surface of the CGF by adopting a constant current density electrodeposition method to form a few layers of bismuthene nanosheets, so as to prepare the BieneNF-CGF electrode. The prepared electrode shows excellent electrochemical activity and interface stability, the electrode reaction kinetics and the overall performance of the battery can be remarkably improved, high-rate, high-energy-efficiency and long-cycle-life all-vanadium redox flow battery application is achieved, and good industrial application prospects are achieved.

This invention provides a method for preparing (002) crystal-plane oriented metallic zinc and its application. The invention employs a two-electrode electrochemical deposition technique, using iron foil, titanium foil, or copper foil as the working electrode, commercial zinc foil as the counter electrode, and an aqueous zinc salt solution as the electrolyte. Constant current density discharge deposition is used to deposit (002) crystal-plane oriented metallic zinc on the working electrode; the constant current density is 50 mA cm⁻¹. ‑2 ~200 mA cm ‑2 The (002) crystal-plane oriented metallic zinc prepared by this invention can be used in rechargeable zinc-ion batteries. The two-electrode electrolytic cell device used in the preparation of metallic zinc in this invention is simple, the preparation process is straightforward, and the preparation method is more universal. The (002) crystal-plane oriented metallic zinc prepared according to the method of this invention can suppress zinc dendrite growth and hydrogen evolution, thereby improving the service life of rechargeable zinc-ion batteries.

A method of anodizing an aluminum alloy, comprising the steps of: providing an anodizing bath containing tert-butoxide, primarily oxalic acid; aging the anodic oxidation bath to condense the metal alkoxide to form metal oxide particles and an acid ester; heating the bath to 40 DEG C to 80 DEG C; stirring the bath at a speed of 200 to 700 rpm (revolutions per minute); immersing the workpiece in a bath and anodizing at a constant current density of 1 A / dm2 to 4 A / dm2 for 1 to 20 minutes or until the bath voltage reaches a threshold value of 100 to 200 V; the workpiece is then anodized at a constant voltage for 20 minutes to 200 minutes to produce an anodized surface having a thickness of 5 microns to 100 microns, the anodized surface comprising an optically discontinuous pore structure that produces a white or near-white appearance.

This invention relates to the field of battery separator materials technology, specifically to MXene-functionalized aramid paper-based battery separators, their preparation methods, and applications. Meta-aramid paper is prepared by wet papermaking using short-cut meta-aramid fibers and precipitated fibers. MXene nanosheets are prepared by hydrofluoric acid etching. Using the meta-aramid paper as a substrate, a functional coating is constructed on the surface of the aramid paper by loading a mixture of para-aramid nanofibers and MXene through a vacuum-assisted filtration-layer-by-layer self-assembly method. The resulting functionalized separator is obtained through protonation reduction. The separator, with its three-dimensional porous protective layer constructed from para-aramid nanofibers and MXene, combines physical barrier and chemical bonding, effectively inhibiting polysulfide shuttle. Furthermore, the highly active sites of MXene can activate inert sulfur-containing substances, improving sulfur utilization. When used in assembling lithium-sulfur batteries, the separator achieves an initial discharge capacity of 1244 mAh·g at a constant current density. ‑1 The capacity retention rate is 82% after 200 cycles.

The application relates to the technical field of ammonium oxidation, and discloses an anode material for ammonium oxidation under a low-concentration chloride ion condition and a preparation method thereof.The anode material takes manganese dioxide as a carrier and is loaded with monatomic silver, and the loading amount of the monatomic silver is less than 0.1 wt%.In the preparation process, first, constant current density electrodeposition is carried out to prepare a MnO2 / platinum-coated titanium mesh; then, a wet chemical immersion method is used to load Ag on the MnO2 substrate; finally, high-temperature air atmosphere calcination is carried out to prepare a monatomic Ag / MnO2 anode material.The application utilizes the acid resistance of MnO2 itself and the strong metal carrier interaction between metal Ag and MnO2 to realize stable and continuous electrolysis operation; and Ag and MnO2 realize the enrichment of low-concentration chloride ions at the anode interface through chemical affinity and physical adsorption, thereby realizing the efficient generation of active chlorine under the condition of low-concentration chloride ions.

The invention belongs to the technical field of tantalum capacitors, and particularly relates to a method for reducing high-temperature leakage current of a tantalum capacitor, which comprises the following steps of: 1) passivating a microporous metal plate: passivating the microporous metal plate in concentrated nitric acid, cooling to room temperature and then taking out the microporous metal plate; 2) corrosion of the microporous metal plate: soaking the passivated microporous metal plate in a sodium hydroxide solution, and washing with water; (3) forming: taking the sintered tantalum core as an anode, taking the microporous metal plate treated in the step (2) as a cathode, adding a forming liquid into a forming tank, boosting to a capacity testing voltage at a constant current density of 0.01-0.06 A / g, and then keeping the voltage constant; (4) post-treatment; after the tantalum anode manufactured by the method is subjected to traditional coating, assembling and aging processes, high-temperature and low-leakage-current tantalum capacitor production is realized, and the product percent of pass is high. The microporous metal plate used in the invention has a large specific surface area, and has the effects of low electron density per unit area and uniform electric field distribution in the forming process of tantalum capacitor manufacturing.

The invention relates to the technical field of materials and electro-catalysis, in particular to a method for synthesizing glycine through electro-catalysis of oxalic acid and nitrate. The preparation method comprises the following steps: taking an electrode material loaded with a two-dimensional PbSnS2 catalyst as a working electrode, adopting the working electrode, a reference electrode and a counter electrode to form a three-electrode system, taking a mixed solution composed of an oxalic acid solution and a potassium nitrate solution as an electrolyte solution, immersing one end of the three-electrode system into the electrolyte solution, and carrying out ultrasonic treatment to obtain the two-dimensional PbSnS2 / PbSnS2 composite electrode. The other end is electrically connected with the electrochemical workstation; and continuously introducing inert gas into the electrolyte solution, and electrolyzing the electrolyte solution under constant current density to obtain glycine. According to the preparation method disclosed by the invention, by introducing the two-dimensional PbSnS2 catalyst, the problem that oxalic acid and nitrate are excessively reduced is solved, the reaction efficiency is improved, the reaction energy consumption is reduced, the safety risk is reduced, and the production process is simplified, so that a technical reference is provided for realizing more economical and efficient glycine production.

The invention belongs to the technical field of organic synthesis, and particularly relates to a method for synthesizing a bridged ring derivative through [4 + 2] cycloaddition based on an electrochemical means. The method for synthesizing the bridged ring derivative based on the electrochemical means [4 + 2] cycloaddition comprises the following steps: by taking an anethole derivative 1 and a cyclopentadiene derivative 2 as raw materials, tetrabutylammonium hexafluorophosphate or tetrabutylammonium perchlorate as an electrolyte and an acetonitrile solution as a solvent, carrying out electrolysis in an electrolytic tank at constant current density, and purifying to obtain a bridged ring derivative 3. According to the method, the free radical cation intermediate is generated through anodic oxidation by utilizing constant-current electrolysis under the conditions of no metal and no oxidant, the cycloaddition reaction is realized, the reaction condition is mild, the reaction time is short, the yield is 51-81%, the stereoselectivity is good, and the method is suitable for complex molecule synthesis.

A de-powdered waste battery electrode sheet and its preparation method are disclosed. The preparation method includes: providing a cathode plate, an anode plate, and an electrolyte; the cathode plate comprises a waste battery electrode sheet, the anode plate comprises boron-doped diamond, and the electrolyte comprises a supporting electrolyte, a halide salt, and a pH buffer; immersing the cathode plate and anode plate in the electrolyte and electrically connecting them to carry out an electrochemical reaction; the electrode spacing between the cathode plate and anode plate is 1 mm-10 mm, and the constant current density is 20 mA / cm². 2 -80 mA / cm 2 The de-powdered waste battery electrode sheets are collected from the cathode plate after the electrochemical reaction. The preparation method of this application enables effective separation between the original active material and the current collector in the obtained de-powdered waste battery electrode sheets, with less residual binder on the surface of the current collector and good mechanical properties maintained.

The invention relates to a method for nitrogen removal of chlorine-oxygen free radical ammonia-nitrogen wastewater, which comprises the following steps: by taking ruthenium dioxide / titanium (RuO2 / Ti) as an anode and mesoporous carbon modified carbon paper (CMK-3 / CP) as a cathode, adding sodium sulfate, sodium chloride and iron modified graphene oxide as a particle electrode into a container containing ammonia-nitrogen wastewater to form an electrochemical ammonia-nitrogen nitrogen removal system with double electrodes and the particle electrode; and introducing oxygen into the cathode region and controlling the electrolysis constant current density to realize denitrification treatment of the ammonia-nitrogen wastewater. According to the method, RuO2 / Ti is utilized to oxidize chloride ions into active chlorine (ClO <-> and HClO), meanwhile, mesoporous carbon modified carbon paper is utilized to reduce oxygen into hydrogen peroxide, the generated active chlorine and hydrogen peroxide are enriched in iron modified graphene oxide particles, and the hydrogen peroxide is further cyclically catalyzed by Fe < 2 + > / Fe < 3 + > in the iron modified graphene oxide particles to generate HOO. The generated HO can react with active chlorine to generate ClO, and the ClO can selectively oxidize ammonia nitrogen into nitrogen and can generate chlorine-oxygen free radicals with high steady-state concentration, so that efficient denitrification treatment of the ammonia-nitrogen wastewater is realized.

The present invention relates to the technical field of sewage treatment, and discloses a wettability switchable separation membrane, a preparation method thereof, and a method for achieving membrane cleaning based on electric field-switched wettability. The method comprises the following steps: (1) contacting and mixing a conductive polymer monomer, a dopant, and a phosphate buffer solution to obtain a mixture I; (2) heating the membrane at 30-60°C and 1-2 mA / cm 2 Under a constant current density of , a metal mesh is used as an anode, a graphite plate is used as a cathode, and Ag / AgCl is used as a working electrode to perform electrochemical deposition in the mixture I to obtain a deposited film; and (3) the deposited film is sequentially rinsed and dried to obtain a wettability-switchable separation membrane. The wettability-switchable separation membrane provided by the present invention has a simple and environmentally friendly preparation process, and the method for achieving membrane cleaning based on electric field-switching wettability using the wettability-switchable separation membrane can achieve simple and effective separation of various types of pollutants, and the membrane cleaning process can be successfully completed in a short time.

The invention discloses a charging and discharging method for improving the energy supplementing speed and the energy efficiency of a lithium-carbon dioxide battery. Aiming at the problems of low energy complementing speed, low energy efficiency, short battery life and the like when the existing lithium-carbon dioxide battery is charged by adopting constant current density, the invention provides a charging method adopting constant voltage, namely, under the conditions of fixed cut-off capacity and discharge current density, the lithium-carbon dioxide battery is charged to the cut-off capacity at the constant voltage. Compared with traditional constant-current-density charging, the constant-voltage charging method provided by the invention has the advantages that the charging speed (the charging time is shortened) and the energy efficiency of the lithium-carbon dioxide battery are remarkably improved. The method has excellent universality, is suitable for lithium-carbon dioxide batteries of various different catalyst systems, effectively overcomes the limitation of constant current charging, and is more beneficial to promoting the practical application of the lithium-carbon dioxide batteries.

The application relates to a semiconductor electrochemical gold etching solution and an etching method thereof. The electrochemical gold etching solution is composed of inorganic acid, metal salt, halide, surfactant, decontaminant, defoaming agent and the like, semiconductor wafer anodes and cathodes are immersed in the electrochemical gold etching solution, and the electrochemical single-element gold etching is carried out under a constant current density. By adjusting the composition, pH value, content of the electrochemical gold etching solution and etching conditions, the excellent effects of fast etching rate of the single-element gold on the semiconductor wafer, controllable etching thickness, uniform surface and the like are realized.

The invention provides a sewage advanced treatment method based on a Magneli phase Ti4O7 reactive electrochemical membrane, which comprises the following steps: taking secondary effluent of a municipal sewage treatment plant as a sewage source, pre-filtering, and injecting the sewage into an open type electrochemical reactor; arranging a Magneli-phase Ti4O7 reactive electrochemical membrane at the center of the electrochemical reactor as an anode, arranging a stainless steel mesh at the outer side of the anode as a cathode, and respectively connecting the anode and the cathode to a positive electrode and a negative electrode of a direct-current stabilized power supply; and pumping out the sewage in the electrochemical reactor at a set flow rate and re-injecting the sewage to form a cross-flow circulating mode, applying constant current density to carry out electrochemical oxidation reaction, and taking the effluent after circulating treatment as the advanced treatment effluent. Compared with the prior art, the current efficiency is high, the ARGs removal capacity is high, the antibiotic degradation performance is excellent, secondary pollution is avoided, and an efficient and low-cost solution is provided for advanced sewage treatment.

The application provides a copper-nickel alloy catalytic electrode and a preparation method and application thereof. The copper-nickel alloy catalytic electrode comprises a nickel foam substrate and a copper-nickel alloy vertically loaded on the surface of the nickel foam substrate, the molecular formula of the copper-nickel alloy is Cu 0.81 Ni 0.19 , and the copper-nickel alloy is a nanostructure with a dendritic morphology. The preparation method comprises the following steps: adding copper sulfate, nickel sulfate and ammonium sulfate into water, stirring uniformly to obtain an electrolyte; taking the nickel foam substrate as a working electrode, a saturated silver-silver chloride electrode as a reference electrode, a platinum sheet or a graphite rod electrode as a counter electrode, applying a constant current density to the working electrode to obtain a preset electrode; alternately cleaning the preset electrode with ethanol and distilled water, and vacuum drying to obtain the copper-nickel alloy catalytic electrode. The copper-nickel alloy catalytic electrode prepared by the application has a dendritic morphology, rich active sites and a high specific surface area, and has excellent catalytic activity and stability in the hydrogen production by the electro-catalytic coupling hydrogen evolution reaction of cyclohexanone synthesis adipic acid.

The invention belongs to the technical field of metal electro-deposition, and particularly relates to a preferred electro-deposition method for different crystal faces of metal zinc and application. According to the method, an inert electrode is used as a working electrode, a zinc foil is used as a counter electrode, electro-deposition is carried out in electrolyte by adopting constant current density, the electrolyte is zinc sulfate and water, or zinc trifluoromethanesulfonate, aromatic Lewis base and water, and (002) crystal face orientation metal zinc is obtained when the discharge current density of electro-deposition is 2mA. Cm <-2 >-1A. Cm <-2 >; the electrolyte is zinc sulfate, aromatic Lewis base and water, and the (101) crystal face oriented metal zinc is obtained when the discharge current density of electro-deposition is 50mA. Cm <-2 >. The crystal face relative texture coefficient of the prepared (002) or (101) crystal face orientation metal zinc is larger than 96%, the signal intensity ratio of the main crystal face to the mixed crystal face is larger than 110, and the prepared (002) or (101) crystal face orientation metal zinc can improve the electrochemical performance and prolong the service life as a negative electrode active material of a zinc-based battery.

The invention provides a method for improving the anti-pollution performance of an anion exchange membrane in an electrodialysis membrane assembly and the electrodialysis membrane assembly. The method comprises the following steps: S1, circulating a water-phase solution containing polyphenol monomers in a desalination chamber to enable the water-phase solution to be in contact with an anion exchange membrane, and meanwhile, applying a direct-current electric field with constant current density to enable the polyphenol monomers to be directionally attached to one side, facing the desalination chamber, of the anion exchange membrane; after contacting for a certain time, discharging the water phase solution; s2, enabling the organic phase solution containing the acyl chloride monomer to be in contact with the anion exchange membrane in a desalination chamber so as to generate an interfacial polymerization modification layer on the surface of the anion exchange membrane; and after contacting for a certain time, discharging the organic phase solution. The method realizes in-situ construction of the interfacial polymerization modification layer with ideal and stable anti-pollution performance on the surface of the anion exchange membrane on the premise of not dismounting the membrane stack.

The preparation method of the electrodeposition nickel-cobalt-based water electrolysis hydrogen production catalyst comprises the steps that a conductive substrate serves as a carrier, nickel salt and cobalt salt are dissolved in deionized water, the constant temperature is kept, nickel-cobalt metal is deposited under the constant current density, and the nickel-cobalt-based water electrolysis hydrogen production catalyst is obtained. And washing to obtain the nickel-cobalt catalyst. The catalyst is prepared by adopting a one-step electrodeposition method, the process is simple and controllable, and raw materials are cheap and easy to obtain; the composition and the structure of the catalyst are optimized by controlling the composition and the temperature of the electroplating liquid, the current density and the time of electro-deposition and pretreatment on the substrate, and the electro-catalytic performance and the stability in the water electrolysis hydrogen evolution process are further improved.

The invention relates to a method for producing an alkali metal alcoholate solution L1 in an electrolysis cell E which comprises at least one cathode chamber KK, at least one anode chamber KA, and at least one central chamber KM lying therebetween. The interior IKK of the cathode chamber KK is separated from the interior IKM of the central chamber KM by a separating wall W comprising at least one alkali-cation-conductive solid ceramic electrolyte (=“AFK”) F (e.g. NaSICON). During the electrolysis process for producing the alkali metal alcoholates with F instead of F′, an improved conductivity is provided, whereby for a constant current density, a lower voltage can be used.

The application discloses an electro-catalytic oxidation control method, a control system, a medium and a product, and relates to the field of electric digital data processing. According to the application, the control system determines a COD allowable fluctuation interval based on the instantaneous water inflow COD concentration, then calculates the average current efficiency and uses the same to determine the working current, and then accurately controls the electro-catalytic oxidation process according to the current density and the hydraulic retention time. The adaptive control method can timely respond to the water quality change of the water inflow, ensures that the water outflow meets the standard, avoids energy waste, has higher treatment efficiency and better economy compared with the traditional constant current density control mode, and forms a closed-loop control when the water outflow exceeds the standard.

The invention provides a preparation method of a pyroxasulfone intermediate, which comprises the following steps: reacting a glyoxylic acid aqueous solution with hydroxylamine hydrochloride to obtain glyoxylic acid oxime; s2, adding water into glyoxylic acid oxime obtained in S1 to form a glyoxylic acid oxime solution, transferring the glyoxylic acid oxime solution to a cathode chamber of an electrolytic tank, and then adding buffer salt and sodium chloride; adding a liquid alkali solution into the anode chamber; carrying out electrolytic reaction under the condition of constant current density to obtain a solution containing dichloroformaldoxime; carrying out extraction separation on the solution containing dichloroformaldoxime by adopting an organic solvent to obtain an organic solution of dichloroformaldoxime; mixing isobutene with a solvent, and adding alkali and a catalyst to form an organic phase; the preparation method comprises the following steps: adding dichloroformaldoxime into an organic phase, slowly dropwise adding a solution containing dichloroformaldoxime into the organic phase, carrying out a cyclization reaction, and after the reaction is completed, carrying out filtration and distillation to obtain a target product 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole.

The application relates to the technical field of electrocatalysis, and discloses a preparation method of a self-supporting Ni-based catalyst, which comprises the following steps: immersing a foamed copper into an electrodeposition solution, performing electrodeposition under a constant current density, washing with clean water after taking out, drying, and obtaining the self-supporting Ni-based catalyst; the electrodeposition solution comprises a nickel source, a tungsten source, a citrate, boric acid and sodium chloride. The Ni-W amorphous catalyst is directly grown on the foamed copper substrate through a one-step constant current electrodeposition method, a self-supporting structure is formed, no binder is needed, the active substance is firmly combined with the substrate, is not easy to fall off, and has good stability. By introducing disordered W doping into the Ni, the electrocatalytic nitrate reduction performance of the catalyst is significantly improved: the overpotential is obviously reduced, the current density is significantly increased, and the ammonia production Faraday efficiency is as high as 94% at-0.3 V.

The invention discloses an electrocatalytic oxidation control method and system, a medium and a product, and relates to the field of electric digital data processing. By implementing the application, the control system determines the COD allowable fluctuation interval based on the instantaneous inflow COD concentration, then calculates the average current efficiency and is used for determining the working current, and then accurately controls the electrocatalytic oxidation process according to the current density and the hydraulic retention time. The self-adaptive control method can respond to the quality change of the inlet water in time, energy waste is avoided while it is guaranteed that the outlet water reaches the standard, and compared with a traditional constant current density control mode, the self-adaptive control method has higher treatment efficiency and better economical efficiency. And when the effluent exceeds the standard, the control system can automatically adjust the average current efficiency and re-execute the control flow, so that closed-loop control is formed.

This invention discloses a method for detecting the bipolar plate coating of a proton exchange membrane electrolyzer, relating to the field of proton exchange membrane electrolyzer technology. The detection method includes the following steps: assembling titanium sheets with a bipolar plate coating in an electrolyzer to obtain an electrolyzer containing titanium sheets; first, cyclically activating the electrolyzer containing titanium sheets at different current densities, and then operating it at a constant current density to test the stability of the bipolar plate coating. This invention introduces titanium sheets coated with a bipolar plate into the electrolyzer and performs operating condition tests to realistically reproduce the corrosive environment of the electrolyzer; the use of thin titanium sheets for testing is very convenient, and further allows for the evaluation of the contact resistance between the coating and the gas diffusion layer of the electrolyzer, as well as morphological characterization such as scanning electron microscopy (SEM), thereby more accurately and intuitively evaluating the lifetime and surface conductivity of the bipolar plate coating, and assessing the degree of corrosion on the coating surface.