52 results about "Electrochemical kinetics" patented technology

The invention provides a laminated lithium metal battery negative electrode material, a preparation method thereof and a lithium metal secondary battery. The preparation method is characterized in that: a lithium-philic metal layer capable of being alloyed with lithium is prepared on the surface of a metal lithium negative electrode or a lithium-free negative electrode current collector, and an artificial lithium ion diffusion layer is prepared on the surface of the lithium-philic metal layer, wherein the lithium-philic metal layer has the functions of reducing nucleation and diffusion barriers of lithium and accelerating electrochemical kinetics of an electrode interface; and the artificial lithium ion diffusion layer has the functions of stabilizing the metal lithium surface and adjusting lithium ion diffusion. A multi-stage functional modification layer of the laminated lithium metal battery negative electrode can inhibit the generation of lithium dendrites, and the cycling stability of the metal lithium negative electrode is improved.

The invention discloses a test device and a method for evaluating scouring corrosion of an oil-gas pipeline under a high flow rate. The test device comprises a thin liquid layer scouring channel and a fluid storage tank, wherein a fluid inlet and a fluid outlet of the thin liquid layer scouring channel are communicated with an outlet and an inlet of the fluid storage tank respectively to form fluid circulation; a plurality of sample mounting openings are formed in the thin liquid layer scouring channel; an electrochemical sample mounting opening and a shearing force mounting opening are electrically connected with an electrochemical workstation and a shearing force sensor respectively; signal output ends of the electrochemical workstation and the shearing force sensor interact with a computer. Through the test device and the method for evaluating scouring corrosion of the oil-gas pipeline under the high flow rate, the corrosion test and the characterization technique under scouring under the high flow rate in the thin liquid layer are achieved; through an electrochemical test system, the electrochemical kinetic test and the thermodynamic test under the high-flow-rate scouring state are achieved; through change of the surface state of the sample and the geometrical shape of the surface of the sample, the scouring behavior of the inner surfaces of pipelines in the actual working conditions can be simulated.

The invention discloses a method of measuring electrochemical kinetic parameters of an electrode active material. The method includes: measuring charging and discharging curves and cyclic voltammetry curve of a positive electrode; studying the charging and discharging curves according to data obtained by measuring and simulating the cyclic voltammetry curve according to Fick diffusion laws and formulas I, II, III and IV to obtain diffusion coefficient and interface reaction constant of the electrode active material. Compared with conventional Nernst equation fitting, the method has the advantages that interference of internal factors like concentration polarization can be eliminated, some characteristic parameters which are most intrinsic of the electrode active material can be reflected truly, and the method has quite high value in the field of academic research; a scientific method is provided for comprehensive and in-depth understanding of the electrode active material, and a theoretical basis is provided for designing batteries more reasonably.

The invention relates to the field of a lithium sulfur battery, and aims at providing a lithium sulfur battery adopting stannous sulfide as an anchoring center and a preparation method of a positive electrode of the lithium sulfur battery. The preparation method of the lithium sulfur battery adopting the stannous sulfide as the anchoring center specifically comprises the following steps: preparing a macroporous carbon material with nano stannous sulfide being dispersed on the inner wall and a macroporous carbon material with supported sulfur, preparing an anode material of the lithium sulfur battery by utilizing the macroporous carbon material with supported sulfur, preparing the positive electrode by utilizing the positive electrode material, and assembling the positive electrode, a diaphragm, a negative electrode and electrolyte to form the lithium sulfur battery. The prepared high-capacity lithium ion battery positive electrode material is good in conductivity, low in internal resistance, good in electrode reaction reversibility, good in chemical stability and thermal stability, low in price, easy to prepare and pollution-free, so that the electrochemical dynamics performance of the lithium sulfur battery positive electrode can be improved, the electrode polarization can be alleviated, and the speed capacity of the lithium battery can be improved.

The invention relates to a preparation method of a lithium ion battery anode material, aiming to provide a method for preparing a conducting film LiFePO4 cladding material containing nitrogen. The method comprises the following steps of: ball milling and mixing FePO4.4H2O, LiOH.H2O and a polyacrylonitrile emulsion, blending into a paste and putting the paste into a quartz reactor; regulating and controlling the microwave output power and controlling the reaction temperature to be at 150 DEG C; raising the microwave output power in an oxygen atmosphere and heating up to 300 DEG C from 150 DEG C; switching to a highly pure nitrogen atmosphere, raising the microwave output power and heating up to 600 DEG C from 300 DEG C; and continuously raising the microwave output power under the highly pure nitrogen atmosphere and annealing at 700-800 DEG C for denitrifying. Nitrogen atoms remain on the conducting carbon film formed by the invention, and lone pair electrons of the nitrogen atoms can effectively improve the conductivity of the carbon film so as to improve electrochemical and dynamic properties of the anode, reduce the electrode polarization and improve the velocity volume of the lithium cell, thus the invention can be applied to power cells of electric vehicles.

The invention relates to a lithium ion battery technology and aims to provide a method for preparing a carbon-coated aluminum lithium battery negative pole material with a core-shell structure and a cavity. The method comprises the following steps of: dissolving a carbon source material into deionized water; adding spherical aluminum powder and magnetons, and then sealing a reaction kettle; performing reaction at the temperature of 250 DEG C, and filtering to obtain brown or black solid powder; performing centrifugal separation and washing, and then performing vacuum drying to obtain a carbon aluminum composite material precursor; carbonizing at constant temperature under the protection of a nitrogen atmosphere, cooling, and post-processing through acid or alkali; and performing vacuum drying to obtain a carbon-coated aluminum composite material with the cavity in a carbon shell. The carbon-coated aluminum composite material in the core-shell structure has the characteristics of normal shape and uniform grain size; and the performance of an electrode material can be stabilized, and a product is high in quality. The carbon shell is uniform in thickness and high in conductivity, so that the electrochemical kinetics performance of a negative electrode is improved, the polarization of the electrode is reduced, and the speed capacity, reliability and safety of a lithium battery are improved.

The invention discloses a test device and a method for evaluating scouring corrosion of an oil-gas pipeline under a high flow rate. The test device comprises a thin liquid layer scouring channel and a fluid storage tank, wherein a fluid inlet and a fluid outlet of the thin liquid layer scouring channel are communicated with an outlet and an inlet of the fluid storage tank respectively to form fluid circulation; a plurality of sample mounting openings are formed in the thin liquid layer scouring channel; an electrochemical sample mounting opening and a shearing force mounting opening are electrically connected with an electrochemical workstation and a shearing force sensor respectively; signal output ends of the electrochemical workstation and the shearing force sensor interact with a computer. Through the test device and the method for evaluating scouring corrosion of the oil-gas pipeline under the high flow rate, the corrosion test and the characterization technique under scouring under the high flow rate in the thin liquid layer are achieved; through an electrochemical test system, the electrochemical kinetic test and the thermodynamic test under the high-flow-rate scouring state are achieved; through change of the surface state of the sample and the geometrical shape of the surface of the sample, the scouring behavior of the inner surfaces of pipelines in the actual working conditions can be simulated.

The invention relates to a preparation method of a porous nickle current collector of a lithium ion battery and relates to the field of materials of lithium ion batteries. The preparation method comprises the following steps: granulating to obtain mixed powder by adopting nickle oxide and graphite as initial materials; pressing into a green blank body and calcining to obtain a blank body; reducing the blank body to obtain a porous nickle current collector of the lithium ion battery; mixing and grinding a transition-metal-oxide negative material with a nano structure, a bonding agent and a pore forming agent, then uniformly coating the surface of the porous nickle current collector of the lithium ion battery with the mixture I, and sintering to obtain an electrode of the lithium ion battery; uniformly mixing a lithium source, an iron source, phosphate radical solution and an organic complexing agent, coating the surface of the porous nickle current collector of the lithium ion battery with the mixture II; and ageing and calcining to obtain a thin-film electrode made of lithium iron phosphate. The porous nickle current collector of the lithium ion battery has the advantages that due to good communicating characteristics, electrons can be relatively well transferred; due to a relatively high three-phase interface, electrolyte and a negative electrode can be relatively well infiltrated mutually; the thin-film electrode made of the lithium iron phosphate has the communicated three-phase interface, so that the convenience is brought for improving the electro-chemical dynamic characteristics of the material.

Methods and compositions for applications related to the microbiologically influenced corrosion (MIC) are provided. MIC is becoming increasingly important, especially to the oil and gas industry due to water flooding practice and aging pipelines. The lack of understanding of the fundamental mechanisms in MIC have greatly hindered the development of reliable prediction and new mitigation methods. This disclosure demonstrates how a biocatalytic cathodic sulfate reduction (BCSR) theory, together with bioenergetics, electrochemical kinetics, and mass transfer, can be used with regard to MIC. The discovery of MIC promoters (that are electron mediators) allows for a new detection tool for more accurate assessment of MIC pitting, and potential new mitigation methods that targets the promoters or microorganisms that secrete these promoters. An MFC device to detect the presence of MIC promoters is provided. When accelerated MIC pitting is desired, such as destruction of undersea munitions or accelerated MIC lab tests, MIC promoters can be added.

The invention relates to the technical field of lithium ion batteries, and particularly relates to a high-stability long-service-life metal lithium negative electrode material and a preparation methodthereof, and more particularly relates to a method for passivating the surface of metal lithium by utilizing low-temperature gallium-based liquid metal, reducing the reaction activity of the metal lithium and stabilizing a metal lithium negative electrode. The high-stability long-service-life lithium metal negative electrode material is lithium metal with an optimized lithium-based alloy passivation layer. The method comprises the steps of coating the surface of metal lithium with a layer of low-temperature gallium-based liquid metal, and then carrying out alloying reaction in an inert atmosphere so as to obtain the product. The low-temperature gallium-based liquid metal which is low in melting point, good in flowability, good in conductivity, lithium-friendly and non-toxic is used for coating the surface of the metal lithium with high reaction activity; and a lithium-based alloy passivation layer with good lithium affinity, corrosion resistance and high ion diffusion coefficient is formed on the surface of the metal lithium, so that the nucleation barrier of lithium is reduced, the electrochemical dynamics of an electrode interface is accelerated, the cycling stability of the metal lithium is improved, and the service life of the metal lithium is prolonged.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention relates to a nano colloidal silica lead-acid battery, which prolongs the service life and increases the capacitance by overcoming the defect of early-stage capacitance loss of the lead-acid battery and belongs to the technical field of surface chemical and electrochemical kinetics. The accumulator is characterized in that the nano gas phase silicon dioxide (SiO2) (Fureed SiO2) (familiarly known as white carbon black) is applied to the regular valve-regulated lead-acid (VRLA) battery structure. The nano colloidal silica lead-acid battery is characterized by prolonging the service life and increasing the capacitance by overcoming three kinds of early-stage capacitance losses of the battery.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention discloses a vanadium-based hydrogen storage alloy, and belongs to the technical field of nickel-hydrogen battery development. The chemical formula of the alloy is V2TiNi0.5Cr0.5Mx, x islarger than 0 and smaller than or equal to 0.2, and M is at least one of La, Ce, Y, Sc, Nd, Gd, Er, and Yb. According to the alloy, the advantages and disadvantages of rare earth hydrogen storage alloy and vanadium-based hydrogen storage alloy are considered, V, Ti, Cr and Ni are used as matrix alloys, La, Ce, Y, Sc, Nd, Gd, Er and Yb in rare earth are used as modified metals, and after rare earthelements are introduced into the vanadium-based hydrogen storage alloy, on the one hand, the discharge capacity of the hydrogen storage alloy serving as a nickel-hydrogen battery anode material can be improved, and on the other hand, the electrochemical kinetics performance of the alloy electrode can be improved. The technical problems of low actual discharge capacity and insufficient kinetics performance of the existing nickel-hydrogen battery are solved.

The invention provides a lithium iron phosphate positive electrode material as well as a preparation method and application thereof. The preparation method comprises the steps of (1) mixing a lithium source, an iron source, a phosphorus source and a solvent, and carrying out a hydrothermal reaction to obtain a lithium iron phosphate crystal; (2) grinding the lithium iron phosphate crystal obtained in the step (1), and sieving to obtain lithium iron phosphate particles with a first particle size and lithium iron phosphate particles with a second particle size; and (3) mixing the lithium iron phosphate particles with the first particle size and the lithium iron phosphate particles with the second particle size, which are obtained in the step (2), to obtain the lithium iron phosphate positive electrode material. According to the invention, firstly, the lithium iron phosphate crystal is prepared in a high-pressure heat-insulating ideal environment through a hydrothermal synthesis process, and by doping lithium iron phosphate active materials with different specific particle sizes, the diffusion impedance is reduced, the electrochemical kinetics is improved, and the low-temperature rate discharge performance of the lithium iron phosphate battery is improved.

The invention discloses a surface modified current collector and a preparation method and an application thereof. The preparation method comprises the steps of providing a substrate; depositing a MoS2 / metal composite film on the surface of the substrate by adopting a magnetron sputtering technology to obtain a surface modified current collector, wherein the MoS2 / metal composite film includes a MoS2 / Ag composite film, a MoS2 / Ti composite film, a MoS2 / Pb composite film and the like. The MoS2 / metal composite film prepared by the magnetron sputtering method not only increases the surface roughnessof the substrate and enhances the bonding power between an active substance and the current collector, but also reduces the contact resistance, improves the electronic conductivity, optimizes the electrochemical dynamics between interfaces, facilitates improving the electron collection capability and suppressing the interface diffusion of Li<+> and can effectively improve the performance of the lithium ion battery. In addition, the preparation method is mature in process, can uniformly deposit in a large area, has small damage to the shape and structure of the substrate, and has high treatment efficiency and wide application prospects.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention discloses a preparation method and application of a vesicular phosphate ion functionalized cobalt oxide nano material, and relates to the technical field of electro-catalysis, in particular to preparation of an electrode material. The precursor used by the vesicular P-CoOx nano material is nontoxic and environment-friendly in raw material, low in cost and simple in process, is prepared through simple calcination, and is easy to operate. The vesicles can be obtained from various cobalt oxides, and continuous large-scale production is easy. The phosphate ions can modify the surface of the transition metal oxide so that the surface active sites of the OER electro-catalytic reaction are increased, the electron transmission is improved, the charge transfer resistance is reduced, and the electro-catalytic performance of the OER is remarkably improved. The vesicular P-CoOx nano material can obviously reduce the overpotential during electrochemical water decomposition, and has the advantages of better electrochemical stability, electrochemical kinetic effect and the like.

The invention discloses a nitrogen-doped hollow-structure graphite microsphere negative electrode material and a nitrogen-doped hollow silicon / silicon monoxide / graphite composite negative electrode material, the hollow graphite microspheres are adopted, and the internal superfine graphite sheets have a random orientation so that the problem that lithium ion diffusion is blocked in the charging and discharging process can be reduced, electrolyte permeation is facilitated, an electrochemical kinetics process is promoted, meanwhile, the hollow structure can relieve the expansion stress of the graphite sheets in the charge-discharge process and provide a required space for the volume expansion of silicon. And nano silicon is converted into silicon monoxide so that the expansion effect of the material is further relieved. The nitrogen-doped carbon layer can improve the conductivity of the material, prevent a side reaction between an electrolyte and an active material, improve the first coulombic efficiency of the material and maintain the structural stability of the material.

The invention discloses a production method of a flexible self-support lithium-sulfur-battery positive-electrode material. The production method has the advantages that an MOF / CNT self-support composite membrane is used as the conductive substrate of an active substance, the active substance sulfur is effectively bound in MOF holes by utilizing the rich hole structures of MOF, the dissolving lossof the active substance sulfur is relieved, and a battery shuttle effect is inhibited; CNT allows an electrode to have good conductivity, guarantees the electrochemical kinetics properties of the active substance and also allows the electrode to have high mechanical stability and self-support performance; by the synergic effect of the MOF material and the CNT, high battery capacity and high battery circulating stability are achieved; the method is simple, low in cost, capable of being favorably popularized, evident in effect, good in practicality and capable of being widely applied in new-generation high-energy flexible batteries.

The invention discloses a high-nickel ternary lithium ion battery positive electrode material and a preparation method thereof. The high-nickel ternary lithium ion battery positive electrode material LiNixCoySczO2 (x is greater than or equal to 0.85 and less than or equal to 0.90, y is less than or equal to 0.1, z is less than or equal to 0.1, and x + y + z = 1) is prepared by adopting a Sc3+ doping strategy, the mixed arrangement degree of lithium and nickel ions is reduced by Sc doping, the stability of a crystal structure is enhanced, and the cycle performance of LiNixCoySczO2 is improved; the chelating agent is utilized to realize uniform mixing of the reaction raw materials on the molecular level, reduce the reaction temperature and shorten the reaction time, so that LiNixCoySczO2 with fine particles can be obtained, the diffusion path of lithium ions in the LiNixCoySczO2 solid particles is remarkably shortened, the electrochemical dynamic performance of the lithium ions is improved, the rate capability of the material is improved, and the material has the advantages of high capacity, long service life and excellent rate capability.

The invention relates to a vanadium pentoxide (V2O5) material with a large specific surface area and a preparation method thereof. The V2O5 material is formed by irregularly cross connecting a plurality of tubular nanometer crystals; a tube wall of each tubular nanometer crystal is formed by mutually connecting single crystal particles; and holes exist among the particles. The preparation method of the material comprises the following steps of: adopting a chemical vapor deposition method; using a CVD (Chemical Vapor Deposition) preparation system; taking vanadyl acetylacetonate (VO (acac) 2) as a raw material; putting into an evaporator; and reacting steam formed by the evaporator with oxygen in carrier gas under a certain temperature to synthesize a V2O5 porous nanometer structure. The advantages are that: the V2O5 material has the large specific surface area, and has good circularity, quick Li ion electrochemical kinetics action and large storage capacity as a Li battery cathode material; and the synthesization process is simple, the purity of the material is high, the yield is large, the energy consumption is low, and the V2O5 material is suitable for being industrially produced in large scale and has good application prospect.

The invention provides a lithium titanate material, a preparation method thereof and a lithium titanate battery containing the lithium titanate material and belongs to the technical field of preparation of a lithium ion battery negative electrode material. The lithium titanate material has a hollow cubic structure. The hollow cubic structure can significantly increase the specific surface area ofthe lithium titanate material, shorten an electron transport path, improve the electronic conductivity of the lithium titanate material and improve the electrochemical kinetic performance. Through thecubic morphology design, the stability of the micron-sized cube morphology is improved and the active crystal face of the nano-sized particles is exposed so that the rate performance and electrochemical activity of the lithium titanate material are improved. Compared with the existing lithium titanate, the lithium titanate material has a better specific surface area, a stable structure and higherreaction activity.

The invention belongs to the technical field of capacitors, and particularly relates to a preparation method of a self-healing flexible solid-state supercapacitor. The preparation method of the self-healing flexible solid-state supercapacitor comprises the following steps: (1) preparing polydopamine-polyacrylamide-sulfuric acid hydrogel; (2) preparing a polyaniline flexible supercapacitor. According to the method, the hydrogel capacitor is synthesized in one step, so large interface resistance caused by poor contact between an electrode material and an electrolyte is greatly reduced, and the contact between the electrolyte and a conductive polymer improves the performance of the supercapacitor by providing excellent electrochemical dynamic performance and remarkable structural stability.

The invention provides a positive electrode material of a lithium-sulfur battery, a preparation method thereof, a positive plate and the lithium-sulfur battery. The positive electrode material contains dedoped polyaniline. The preparation method of the positive electrode material includes the steps that 1, the dedoped polyaniline is prepared; 2, a dedoped polyaniline solution is prepared; the positive electrode material is prepared. The positive plate comprises a current collector and an active layer combined with the surface of the current collector, wherein the active layer contains the positive electrode material. The lithium-sulfur battery comprises the positive plate. During charging and discharging, the positive electrode material generates new electrochemical kinetics behaviors to restrain a shuttle flying effect, and the structure is simple. The positive plate comprising the positive electrode material has the advantages that the gram volume of active substances is high, the dissolve-loss rate of the active substances is low, and the structure is stable; according to the lithium-sulfur battery including the positive plate, the specific capacity is accordingly increased greatly, and the cycle life is accordingly prolonged greatly.

The invention relates to a cathode electrode coating of a sodium hypochlorite generator. The cathode electrode coating comprises an electrode substrate, electric catalyzing layers, interlayers and transitional layers. The structure sequentially comprises the first electric catalyzing layer, the first interlayer, the first transitional layer, the electrode substrate, the second transitional layer, the second interlayer and the second electric catalyzing layer, wherein the electric catalyzing layers are made of a RuO2-IrO2 material. The roughness of the surface of the electrode substrate is large, the electrode substrate is high in electrocatalytic activity and has excellent corrosion resistance and oxidation resistance under the alkaline environment, the electrolytic efficiency is high, and oxidation is not prone to occurring. The hydrogen evolution potential of the electrode substrate is extremely low, the related electrochemical kinetic parameters before operation are kept after long-term operation, the stability is good, the service life is long, and the catalyzing cost is low. By adopting the RuO2-IrO2 electric catalyzing layers with the certain ratio, the hydrogen evolution activity is further optimized. By introducing the PdO transitional layers, binding force of every two adjacent layers is reinforced, and the active component reduction negative influence caused by falling-off is also eliminated.

The invention provides a positive electrode material of a lithium-sulfur battery composite electrode as well as a preparation method and application of the positive electrode material. The positive electrode material comprises a three-dimensional carbon nanofiber substrate material, the three-dimensional carbon nanofiber substrate material is of a three-dimensional porous carbon net structure, adsorption points are arranged on the three-dimensional carbon nanofiber substrate material, and the adsorption points are used for adsorbing cobalt-iron alloy nanoparticles. The preparation method comprises the following steps: soaking raw materials of a three-dimensional carbon nanofiber substrate material in a metal mixed salt solution to obtain a precursor, and sequentially carrying out drying treatment and high-temperature reduction treatment on the precursor to obtain the positive electrode material. The porous structure of the carbon network is in effective contact with the soluble intermediate polysulfide, so that the utilization of sulfur is promoted, and the electrochemical kinetics of sulfur-containing species in the electro-catalysis process is accelerated. According to the preparation method, a simple impregnation-reduction method is adopted, the electronic structure of the monomer is optimized, and the catalytic activity is improved.