81 results about "Cyclic voltammetry" patented technology

The embodiment of the invention provides a silicon-carbon negative electrode material and a preparation method thereof, a negative electrode plate and a battery, the silicon-carbon negative electrode material comprises a silicon-carbon inner core and a coating layer coating the silicon-carbon inner core, and the silicon-carbon inner core comprises a porous carbon substrate and nanometer silicon arranged on the porous carbon substrate. The test result of the first cyclic volt-ampere test of the silicon carbon negative electrode material meets at least one of the following conditions: (a) the value of dQ / (dV * C) of a discharge differential capacity curve in a voltage interval of 0.45 V + / -0.05 V is less than or equal to 1.7, dQ / dV represents differential capacity, the unit is mAh / V, C represents charge capacity, and the unit is mAh; (b) no sharp peak exists in a discharge differential capacity curve in a voltage interval of 0.45 V + / -0.05 V, the battery can present a smooth and stable discharge process, the capacity retention ratio and the stability of the battery after circulation are improved, and the preparation method is simple, convenient and feasible, and is suitable for industrial production.

The present invention relates to a layered composite electrode and its preparation method and application. The electrode uses nickel foam as the base layer, grows a layer of manganese phosphide on its surface by hydrothermal method, and then deposits Co oxide on the surface of the manganese phosphide layer by cyclic voltammetry (CV) electrodeposition technology. After cleaning and drying, Co z O / Mn y P x The catalyst on the surface of the / NF electrode presents a nanosheet structure. The Mn x The lattice of P nanomaterials is distorted and its electronic structure is optimized, which increases the oxygen vacancy content and thus improves the oxygen evolution performance of the catalyst.

The invention provides a micro-nano porous multi-principal element alloy material, a preparation method thereof and application of the micro-nano porous multi-principal element alloy material in electro-catalysis cinnamyl aldehyde hydrogenation. The preparation method of the micro-nano porous multi-principal element alloy material comprises the following steps: uniformly mixing three or more than four element raw materials of Co, Cr, Fe, Ni and Cu, and carrying out smelting, suction casting, cutting and annealing to obtain an alloy sheet; carrying out vacuum tube sealing on the alloy sheet and zinc particles, and carrying out a heating reaction to obtain a zincized principal element alloy; carrying out a metal Zn removal reaction in an argon-hydrogen mixed gas atmosphere to obtain a porous multi-principal-element alloy; and the porous multi-principal-element alloy is subjected to cyclic voltammetry treatment in a mixed solution of isopropanol and an acetic acid buffer solution, and the micro-nano porous multi-principal-element alloy material is obtained through washing and drying. The method is easy and convenient to operate, the production period is greatly shortened, and batch production capacity is achieved. The prepared porous multi-principal element alloy material shows excellent catalytic activity and stability in electro-catalysis cinnamyl aldehyde hydrogenation.

The invention belongs to the technical field of electrochemical analysis and detection, and particularly relates to an electrochemical immunosensor for detecting adiponectin as well as a preparation method and application of the electrochemical immunosensor. The preparation method comprises the following steps: (1) connecting a screen-printed electrode SPCE to an electrochemical workstation by using a 0.01 M PBS (Phosphate Buffer Solution) with the pH value of 7.4, performing-0.2 V-1. 2V cyclic voltammetry scanning, and activating for 10 circles under 50mV / S; and (2) by taking 0.01-1M H2SO4 as a base solution, connecting the screen-printed electrode SPCE to an electrochemical workstation, carrying out electro-polymerization on poly-o-phenylenediamine in a 50-100mM o-phenylenediamine and NH2-UiO-66 solution to form a poly-o-phenylenediamine and NH2-UiO-66 composite modified electrode, washing with deionized water, and drying at room temperature. (3) soaking the modified electrode in a glutaraldehyde solution for 10-70 minutes, cleaning with deionized water, drying at room temperature, adding 10-100 [mu] L of ADPN antibody solution and 100-600 [mu] g / mL of ADPN antibody solution, and incubating; and (4) washing with ionized water, drying at room temperature, preventing non-specific binding sites at 37 DEG C for 0.5-1.5 hours by using 3-10 microliters of 0.8-1.2 wt% casein solution, and washing the screen-printed electrode again to obtain the electrochemical immunosensor.

The application relates to the technical field of calcium ion batteries, in particular to a preparation method of a Ca-I2 double-ion battery, which specifically comprises the following steps: (1) placing 5M CaCl2 aqueous solution as an electrolyte in an electrolytic cell; (2) placing elemental iodine and activated carbon fiber cloth in a sealed glass container to carry out iodine fixation, and the carbon fiber cloth after the iodine fixation is used as a positive electrode material; (3) obtaining an electrode sheet by drying the carbon fiber paper coated with slurry, and activating the fully dried electrode sheet through an electrochemical cyclic voltammetry method, and the activated electrode sheet is used as a negative electrode material; and (4) placing the positive electrode material and the negative electrode material in the electrolyte together, and obtaining the Ca-I2 double-ion battery through matching, wherein the preparation method of the Ca-I2 double-ion battery shortens the diffusion distance of calcium ions by half, and the positive electrode carries out a rapid oxidation-reduction reaction, so that the whole battery has good rate performance, high power density and energy density.

The invention provides a V10-coated FeCo-MIL / BiVO4 composite photo-anode based on dissociation reconstruction interface strengthening as well as a preparation method and application of the V10-coated FeCo-MIL / BiVO4 composite photo-anode. According to the photoanode, BiVO4 loaded on FTO conductive glass serves as a substrate, V10 nanoclusters and a FeCo bimetal organic framework (FeCo-MIL) are synchronously loaded on the surface of the BiVO4 through a one-step solvothermal reaction, and a ternary composite structure is formed. The core innovation of the invention lies in that the composite photoanode is subjected to electrochemical activation treatment by adopting cyclic voltammetry subsequently, and FeCo-MIL is induced to generate controllable dissociation and dynamic reconstruction, so that strong interface interaction is constructed between FeCo-MIL and V10 and BiVO4, and an efficient charge transfer channel is formed. The material is simple in preparation process and low in cost, and shows excellent performance in the field of photoelectrocatalytic water decomposition. Under the irradiation of AM 1.5 G simulated sunlight and the potential of 1.23 V vs. RHE, the initial photocurrent density can reach 5.0 mA cm <-2 >, after cyclic voltammetry activation treatment, the photocurrent density is further increased to 5.8 mA cm <-2 >, the operation stability is enhanced, and the photoelectrocatalytic activity is remarkably enhanced.

The invention relates to preparation and application of a foam metal electrode loaded with a polymer film, and relates to a key technology of the foam metal electrode loaded with the polymer film for detecting NADH (Nicotinamide Adenine Dinucleotide Horse), which comprises the following steps: by taking foam metal as a substrate, electrically polymerizing the polymer film on the substrate in a cyclic voltammetry mode to obtain the foam metal electrode loaded with the polymer film; nADH with different concentrations is detected by using the NADH as a working electrode, Pt as a counter electrode and saturated calomel as a reference electrode. The invention provides a rapid and sensitive method for electrochemically detecting NADH by virtue of good conductivity, large specific surface area and high porosity of the foam metal and high stability and NADH catalysis capability of the conductive polymer and loading the conductive polymer on the surface of the foam metal. The preparation method of the foam metal electrode loaded with the polymer film, provided by the invention, has the advantages of high efficiency, simplicity in operation, obvious effect, low cost and the like, and can be applied to the field of electrochemical sensing.

The invention provides an Ag-CuO / Cu electrode, a preparation method and passion fruit juice detection application, and the preparation method comprises the following steps: cleaning a copper electrode, and then grinding and polishing; the copper electrode obtained after primary treatment is immersed in a 0.5-1.5 M H2SO4 solution, square wave pulse treatment is carried out, and a pretreated copper electrode is obtained; the pretreated copper electrode is placed in a 0.5-1.5 M KOH solution, cyclic voltammetry scanning is carried out, and an activated copper electrode is obtained; and the activated copper electrode is placed in a 0.005-0.05 M AgNO3 solution, and Ag < + > is reduced and deposited on the surface of the copper electrode by adopting a constant potential deposition method to form an Ag modification layer. The Ag-CuO / Cu electrode prepared by the invention is used for detecting ascorbic acid in passion fruit juice, and is high in sensitivity, good in repeatability and reproducibility, excellent in long-term stability and strong in anti-interference capability; and the electrode preparation process is simple.

The invention discloses a preparation method and application of a nickel-molybdenum polyacid-polymer-based self-supporting electrocatalyst with low platinum-carbon loading capacity, and relates to the technical field of electrocatalysts. The preparation method of the electrocatalyst comprises the following steps: weighing raw materials for preparing an electrolyte solution; comprising nickel sulfate, ammonium molybdate, chloroplatinic acid, borax, polyvinyl alcohol and chitosan. Uniformly mixing the raw materials with deionized water to obtain a nickel molybdenum polyacid solution, a borax solution and a PVA-CS solution, obtaining a target electrolyte solution, and soaking the target electrolyte solution with carbon paper; freezing and drying; performing carbonization; the treated carbon paper is used as a working electrode, a saturated calomel electrode is used as a reference electrode, and a graphite electrode is used as an auxiliary electrode; and platinum is electrodeposited on the carbon paper by adopting a cyclic voltammetry electrodeposition method to prepare the electrocatalyst. According to the prepared electrocatalyst, the cost can be reduced, the reaction kinetics of an alkaline solution and alkaline seawater can be improved, the overpotential can be reduced, the stability can be improved, and the alkaline seawater electrolysis process is more economical and efficient.

The application relates to an activation method of a high-loading manganese dioxide electrode material, in particular to in-situ growth of a high-loading manganese dioxide electrode material with a loading of greater than or equal to 15 mg cm ‑2 on a flexible carbon cloth surface, taking the high-loading manganese dioxide electrode material as a working electrode, taking a metal Pt sheet as a counter electrode, adopting a two-electrode system, activating the high-loading manganese dioxide in a zinc nitrate solution through cyclic voltammetry scanning, and the activated high-loading manganese dioxide exhibits excellent electrochemical properties. The application adopts an electric activation method to improve the electrochemical activity of the high-loading manganese dioxide, has the advantages of simple process, convenient operation and the like, and the activated high-loading manganese dioxide electrode material can be used for electrochemical energy storage.

This invention discloses a platinum-cobalt phosphate catalyst for the selective electrooxidation of ethylene glycol to glycolic acid, its preparation method, and its application. The preparation method includes: S1, pretreating nickel foam (NF); S2, dissolving disodium hydrogen phosphate dodecahydrate and hexadecyltrimethylammonium bromide in a mixture of water and ethylene glycol, adding cobalt nitrate and stirring to obtain a precursor; S3, immersing the nickel foam in the precursor solution and refrigerating it overnight at low temperature; S4, transferring it to a reaction vessel and hydrothermally heating it at 160 °C for 10 hours to obtain cobalt phosphate (CoPO / NF); S5, using CoPO / NF as the working electrode, electrochemically depositing platinum in an H2PtCl6 and KOH electrolyte using cyclic voltammetry; S6, washing and vacuum drying to obtain the final product. This invention is the first to prepare a platinum-cobalt phosphate catalyst for the selective electrooxidation of ethylene glycol to glycolic acid at 100 mA cm⁻¹. ‑2 With a working potential of only 0.67 V at current density (relative to RHE) and a Faraday efficiency of 100% for glycolic acid, it has significant advantages and application potential in the highly selective production of glycolic acid in the electro-oxidation reaction of ethylene glycol.

The application discloses a high-performance binder-free nanofiber membrane electrode and a preparation method and fuel cell thereof, and belongs to the technical field of fuel cells. The preparation method comprises the following steps: performing constant potential treatment on a single cell assembled by a nanofiber membrane electrode under the condition that air is passed through a cathode and hydrogen is passed through an anode, performing nitrogen blowing on the cathode and hydrogen blowing on the anode for a set time after the treatment is completed, then performing cyclic voltammetry scanning on the cathode and the anode under the condition that nitrogen is passed through the cathode and hydrogen is passed through the anode, and the high-performance binder-free nanofiber membrane electrode is obtained; wherein, a cathode catalytic layer of the nanofiber membrane electrode is prepared by an electrostatic spinning method. The preparation method can effectively remove the binder in the nanofiber membrane electrode, significantly improves the utilization rate and catalytic activity of the catalyst and the working performance of the membrane electrode, and is simple and easy to operate.

The application discloses a method for photocatalytically preparing 3-aminoquinoxalin-2(1 H )-ketone compounds, and belongs to the field of organic synthesis. The application comprises the following steps: quinoxalin-2(1 H )-ketone compounds, fatty amine compounds, a photocatalyst mpg-C3N4 (mesoporous graphite phase carbon nitride) and an alkali DABCO (1,4-diazabicyclo (2.2.2) octane) are added into an organic solvent and uniformly mixed; the reaction is carried out under the irradiation of light in an oxygen atmosphere; and after the reaction is completed, the 3-aminoquinoxalin-2(1 H )-ketone product is obtained through treatment and separation. The application uses DABCO as an alkali and an electron transfer agent, and adopts mpg-C3N4 to photocatalytically prepare 3-aminoquinoxalin-2(1 H )-ketone compounds under the auxiliary condition of DABCO, and it is concluded from DABCO quenching experiments and cyclic voltammetry experiments that there is a single electron transfer relationship between them; and the application has the advantages of mild reaction conditions, simple operation and the ability to synthesize 3-aminoquinoxalin-2(1 H )-ketone compounds in one step.

The invention discloses a cyclic voltammetry curve prediction method, device and equipment, a medium and a product, and relates to the technical field of battery performance prediction. The method comprises the following steps: constructing a first sample set and a second sample set based on a historical cyclic voltammetry curve; training the fusion model by using the first sample set and the second sample set to obtain an upper half curve prediction model and a lower half curve prediction model; and performing cyclic voltammetry curve prediction by using the upper half curve prediction model and the lower half curve prediction model. According to the method, the upper half curve prediction model and the lower half curve prediction model are obtained through sample construction and model training, the situation that prediction is difficult due to the fact that the same voltage corresponds to multiple currents can be avoided, the cyclic voltammetry curve change is accurately predicted through an efficient data driving method, and the accuracy of cyclic voltammetry curve prediction is improved. Therefore, evaluation and optimization of the service life of the fuel cell are realized.

The application discloses a kind of solubility carbon black electron transfer capacity quantitative prediction method, more than three temperature is selected and is prepared carbon black using biomass, is configured into mixed solution by adding water, mixed solution is cultured by shaker, solution is centrifuged, supernatant is filtered, and solubility carbon black solution is obtained;The concentration of solubility carbon black solution is determined, and the cyclic voltammetry curve of carbon black solution is determined using electrochemical workstation and three electrode system, the peak potential corresponding to each scanning speed in the curve, peak current are obtained, according to scanning rate, peak potential, peak current, solubility carbon black solution concentration, electron transfer rate constant k 0 It is calculated by using Bulter-Volmer equation, linear prediction model is constructed by the logarithmic value of electron transfer rate constant k 0 And pyrolysis temperature, the electron transfer capacity of carbon black at different temperatures is predicted using the model;The method is simple and easy to operate, and the electron transfer capacity of solubility carbon black of known raw material type can be directly predicted.

This invention relates to the field of energy storage device technology and provides a method for preparing a high-specific-capacitance hydrated ruthenium oxide cathode material, comprising the following steps: annealing RuO2·xH2O; preparing a slurry by mixing RuO2·xH2O powder with a binder and a conductive agent, stirring, coating it onto carbon paper, and vacuum drying; using a three-electrode system, with the dried carbon paper loaded with RuO2·xH2O powder as the working electrode, performing an activation process, wherein the activation method is one of constant current intermittent titration activation, cyclic voltammetry activation, and constant current charge-discharge activation. This invention also provides a high-specific-capacitance hydrated ruthenium oxide cathode material and its application. This invention lowers the annealing temperature, reducing some of the crystal water in the hydrated ruthenium oxide to a suitable level; then, by using electrochemical constant current intermittent titration cycles to reduce the crystallinity of the hydrated ruthenium oxide, electron transport and ion transport reach the most coordinated state, thereby improving the specific capacitance of the cathode material.

The application discloses a Ce, Nd-MOF-5 / GO / PANI composite material, a preparation method and application thereof. A MOF-5 doped with double rare earth elements is modified as a skeleton, a three-dimensional conductive network is constructed by being combined with graphene oxide, and polyaniline with high conductivity is polymerized by using an in-situ polymerization method. The electrochemical behavior of the composite material is analyzed by performing a cyclic voltammetry test, and the significant advantages of the ternary composite structure in improving the electrode conductivity, promoting the reaction kinetics and enhancing the structural stability are verified, and the ternary composite structure is finally applied to a full vanadium redox flow battery.

The invention discloses a platinum-loaded boron-doped diamond electrode, which is characterized in that monocrystalline silicon is pretreated by using a diamond grinding liquid to obtain seeded monocrystalline silicon, and the seeded monocrystalline silicon is used as a substrate to prepare a boron-doped diamond film electrode by using a hot filament chemical vapor deposition method; then loading platinum by using an atomic layer deposition method, then putting into an acidic electrolyte, connecting an electrochemical workstation by using a standard three-electrode system, and carrying out cyclic voltammetry scanning to obtain a platinum-loaded boron-doped diamond electrode; the potential window of the boron-doped diamond film electrode is remarkably improved, the background current is reduced, and the boron-doped diamond film electrode has wide application prospects in the fields of electrocatalysis, electrochemical sensing, advanced oxidation and the like.

The invention belongs to the technical field of environmental materials, and particularly relates to a method for electrodeposition-assisted biosynthesis of a silver-based catalytic material SSSM-SRB and application of the silver-based catalytic material SSSM-SRB. The invention relates to a method for electrodeposition-assisted biosynthesis of a silver-based catalytic material SSSM-SRB, which comprises the following steps: by taking a sulfate reducing bacteria (SRB) suspension as an electrolyte and a silver net as a working electrode, carrying out electrodeposition by adopting a cyclic voltammetry, and growing Ag2S on the surface of the silver net in situ. The SRB is used for biologically synthesizing Ag2S, the process is environmentally friendly, and use of toxic reagents in traditional chemical synthesis is avoided.

The invention discloses a hepatic fibrosis organ chip sensing device for pathological evaluation and drug screening, which belongs to the technical field of microfluidics and comprises a top cover, an upper culture layer, a porous membrane, a lower culture layer and a glass substrate electrochemical electrode. The sensing device is combined with a hepatic fibrosis organ chip and a three-electrode detection system, gel permeability change is detected on the basis of electrochemical cyclic voltammetry, the hepatic fibrosis process is indirectly evaluated, and then in-vitro rapid screening of hepatic fibrosis potential drugs is carried out. The liver fibrosis organ chip sensing device provided by the invention provides a novel and efficient research means for real-time monitoring and quantitative evaluation of a liver fibrosis in-vitro model. The problems that in the prior art, due to the fact that dynamic and cross-scale substance transmission characteristics in a precise quantification three-dimensional tissue model are still limited, microenvironment changes dominated by extracellular matrix reconstruction are difficult to reflect in a non-invasive and in-situ mode, and the hepatic fibrosis process is difficult to detect are solved.

The invention relates to the field of electrochemistry, in particular to a preparation method of a platinum electrode with controllable morphology. Comprising the following steps: taking a conductive substrate, making the conductive substrate into a long strip shape, then carrying out surface cleaning and drying, and then carrying out packaging to obtain a pretreated conductive substrate; a platinum electrode is dissolved in an acidic electrolyte solution through cyclic voltammetry, and a platinum-containing electrolyte is prepared; taking the pretreated conductive substrate as a working electrode, a platinum metal electrode as a counter electrode and an Ag / AgCl electrode as a reference electrode, putting the working electrode, the platinum metal electrode and the Ag / AgCl electrode into a platinum-containing electrolyte, and preparing the shape-controllable platinum electrode by adopting a cyclic voltammetry method. The preparation method disclosed by the invention is simple to operate and mild in reaction condition, and controllable preparation can be realized only by immersing the anode, the cathode and the reference electrode into the electrolyte and selecting proper cyclic voltammetry parameters.

The present application relates to the technical field of electrochemical sensor, in particular to a kind of molecularly imprinted electrochemical sensor based on β-FeOOH nanoparticle and preparation method thereof.The preparation of the molecularly imprinted electrochemical sensor based on β-FeOOH nanoparticle includes the following steps: step one, preparation of modified electrode: β-FeOOH nanoparticles are grown in situ on carbon cloth using hydrothermal method;Step two, add RC and CBD;Step three, molecularly imprinted polymer (MIP) is polymerized using cyclic voltammetry, and the sensor MIP / β-FeOOH / CC is prepared.The electrode selected in the present application is carbon cloth electrode, which can provide more active sites for molecular imprinting;It is easy to obtain and low in price, and at the same time, it does not need to be polished, which simplifies the preparation process;When preparing, simple one-step hydrothermal method is used, and in repeatability and stability test, the relative standard deviation is less than 5%;The minimum detection limit is 0.025 nM, which can well meet the trace quantitative detection of carbendazim.

The application discloses a synthesis method of an electrochemically reconstructed boron-doped nickel phosphide nanomaterial and applies the boron-doped nickel phosphide nanomaterial to water electrolysis hydrogen evolution under alkaline conditions, and excellent catalytic performance is obtained. The application mainly dopes boron elements in a precursor Ni(OH)2, generates Ni5P4-B through phosphorization treatment, and then forms Ni3(BO3)2 / Ni5P4 through electrochemical reconstruction. After preliminary hydrothermal synthesis of Ni(OH)2 nanosheets, the precursor with the nanosheets is suspended in ice water, and ice water solutions of different concentrations of NaBH4 are dropped to prepare boron-doped Ni(OH)2. The boron-doped Ni(OH)2 precursor is heated and phosphorized in a tube furnace, the sample after phosphorization is fully activated through electrochemical cyclic voltammetry, and a heterostructure Ni3(BO3)2 / Ni5P4 is obtained. The heterostructure Ni3(BO3)2 / Ni5P4 exhibits outstanding electrocatalytic hydrogen evolution activity under alkaline conditions.

The application discloses a self-supporting catalyst and a preparation method and application thereof, and the self-supporting catalyst comprises a foamed nickel substrate and Cu2S particles loaded on the foamed nickel substrate, wherein the Cu2S particles are in a micron flower ball shape; the preparation method comprises the following steps: using a foamed nickel as a working electrode and a reaction substrate by means of an electrochemical three-electrode system, and according to the redox potential of copper, reduction of copper ions and sulfurization of copper are sequentially carried out by means of a constant potential method and a cyclic voltammetry method respectively, so that the self-supporting catalyst is obtained. The self-supporting material Cu2S@NF exhibits excellent catalytic activity and stability in HER and OER as a bifunctional electrocatalyst, has great advantages compared with other non-noble metal electrocatalysts, and has a good application prospect in water electrolysis.

The invention discloses a bimetallic oxide / hydroxide catalyst as well as a preparation method and application thereof, and relates to the technical field of new energy materials. By precisely regulating and controlling the electron synergistic effect between transition metals and optimizing the surface structure, the composite material shows comprehensive performance obviously superior to that in the prior art in the water electrolysis oxygen evolution reaction. Firstly, transition metal is adopted to construct a catalyst through a synergistic doping or composite strategy, an electronic structure and catalytic site distribution can be optimized, the oxygen evolution reaction performance of the catalyst can be improved, meanwhile, through specific electrochemical cyclic voltammetry activation, stable high-valence active species are constructed in situ, a chlorine corrosion resistant layer is dynamically evolved in situ, and the oxygen evolution reaction performance of the catalyst is improved. And low overpotential, high catalytic kinetics and good corrosion resistance are realized. And secondly, non-noble metal elements with high earth crust abundance and low price are adopted, so that the production and use cost of the catalyst is remarkably reduced, and good economic feasibility is achieved. And the method has wide application potential in clean energy conversion systems such as electrolyzed water and seawater electrolysis.

A method for the electrochemical recovery of a metal from a spent electrode is provided. The method comprises the steps of providing an electrochemical cell comprising a metal recovery electrode as a working electrode, the spent electrode as a counter-electrode, and an electrolyte between the working electrode and the counter-electrode, and performing cyclic voltammetry on the metal recovery electrode, thereby dissolving the metal from the spent electrode and adsorbing dissolved atoms of the metal on the metal recovery electrode, thereby recovering the metal and forming a composite electrode. The metal recovery electrode comprising a metal compound on a conducting support and the metal compound is made by a method comprising reacting a metal oxalate or an ammonium metal oxalate, wherein the metal is a group 4 to 6 metal, with a chalcogenide or an organochalcogenide.

The invention discloses an online cleaning and activating method for active sites of a Fe / N / C oxygen reduction catalyst. The method comprises the following steps: firstly, carrying out electrochemical cleaning on a Fe / N / C catalyst in a hydrogen and specific potential range, and removing adsorbates or impurities adsorbed on the surface of a metal active site by utilizing an electrochemical oxidation reaction of hydrogen, so that the Fe active site is exposed and activated; then, observing a Fe < 3 + > / Fe < 2 + > variable valence peak at about 0.85 V (vs RHE) through cyclic voltammetry scanning, and integrating the electric quantity to calculate the Fe active site density. The method is simple and rapid to operate, can be carried out on line in an electrolytic tank or a proton exchange membrane fuel cell, can effectively remove active site impurities, accurately evaluate the active site density of the Fe / N / C catalyst, is beneficial to distinguishing and screening catalysts with different activities, and monitors attenuation caused by the active site density and Fe < 3 + > / Fe < 2 + > potential change when the Fe / N / C catalyst runs for a long time.

The invention is applicable to the technical field of clean energy preparation, and provides a Fe-based catalyst, the catalyst FeSAs + WSAs + Fe-WCNPs / NC is formed by integrating Fe monatomic atoms, W monatomic atoms and Fe-doped WC nanoparticles on an N-doped C substrate, the size of the N-doped C substrate is 100-150nm, and the size of the Fe-doped WC nanoparticles is 2-10nm. According to the invention, by introducing a synergistic effect among Fe monatomic, W monatomic and Fe-WC particles, the oxygen reduction reaction activity in the acidic electrolyte is improved, and the half-wave potential of the acidic electrolyte in 0.1 M HClO4 reaches 0.830 VRHE; after 50,000 cycles of accelerated cyclic voltammetry test, the half-wave potential is attenuated by 14mV, and the material has relatively high electrochemical stability; the material can be used as a cathode material of a proton exchange membrane fuel cell and shows excellent practical performance.

The application belongs to the technical field of gold plating solution, and particularly relates to a plating solution for low-porosity gold plating layer and application thereof. The plating solution comprises a gold salt, a composite grain refiner, a composite pore inhibitor, a complexing agent and water. The composite grain refiner comprises polyethyleneimine and sodium o-sulfobenzamide, and the composite pore inhibitor comprises F-127 and cystamine dihydrochloride. Compared with the prior art, the technical scheme provided by the application has the synergistic effect of the composite grain refiner and the rapid bubble detachment effect of the F-127 block copolymer, so that the obtained gold plating layer is dense and has no pinholes. The gold plating layer has an order of magnitude lower porosity and better corrosion resistance than a traditional cyanide gold plating layer through electrochemical cyclic voltammetry detection. The plating solution is a cyanide-free system, is safe and environmentally friendly, and can be directly applied to an existing probe plating production line without additional equipment investment.

The invention provides a nanocrystalline diamond heterojunction ultraviolet photoelectric detector, which is characterized in that seed crystal pretreatment is carried out on monocrystalline silicon, the obtained seed crystal monocrystalline silicon is used as a substrate, acetone is used as a carbon source, boron-doped nanocrystalline diamond is grown on the surface of the substrate by using a hot filament chemical vapor deposition method, the boron-doped nanocrystalline diamond is placed in a sulfuric acid solution, and the boron-doped nanocrystalline diamond heterojunction ultraviolet photoelectric detector is obtained. And performing cyclic voltammetry treatment. Then, the titanium source precursor is partially covered and placed in atomic layer deposition equipment, and deposition circulation is conducted through the titanium source precursor; and finally, the diamond and Ti areas are coated with silver paste to form an ohmic contact electrode, and the prepared nanocrystalline diamond heterojunction ultraviolet photoelectric detector has excellent response speed, can better adapt to high-speed ultraviolet detection tasks and shows good application prospects in the fields of ultraviolet communication, rapid switch monitoring and the like.