2032 results about "Oxygen evolution" patented technology

Air electrodes for secondary metal-air batteries or secondary metal hydride-air batteries, in particular, bifunctional air electrodes that can undergo oxygen reduction and oxygen evolution with high reaction rates. A method of manufacturing such electrodes.

The invention provides an electrode for electrolysis, a preparation method of the electrode and an electrolytic bath. The electrode for electrolysis comprises a conductive base material and an active coating, wherein the conductive base material is a base material containing titanium or titanium alloy; the active coating at least comprises a bottom coating layer and a surface coating layer; the bottom coating layer is prepared from titanic oxide, iridium oxide and ruthenium oxide; the surface coating layer is prepared from iridium oxide, ruthenium oxide, titanium oxide and a metal or an oxide of one of two of palladium and platinum. According to the electrode for electrolysis disclosed by the invention, the double coating layers are adopted; compared with the single coating layer only containing ruthenium, iridium and titanium, the electrode is better in activity, the chlorine evolution potential of the electrode is low, the oxygen evolution potential is high, the service life of the electrode is longer, and the electrolysis stability is better.

The invention is a fuel cell (20) having a corrosion resistant and protected cathode catalyst layer (24). The cathode catalyst layer (24) includes a platinum oxygen reduction catalyst and an oxygen evolution catalyst selected from the group consisting of catalysts that are more active than platinum for oxygen evolution. The oxygen evolution catalyst may be uniformly applied within the cathode catalyst layer, or non-uniformly applied to identified high corrosion areas (82) (84) of the cathode catalyst layer (24). The cathode catalyst layer (24) may include heat-treated carbon support material, and/or a heat-treated carbon black within a diffusion layer (40) supporting the cathode catalyst layer (24). The fuel cell (20) may also include an anode catalyst layer (22) having a poor oxygen reduction catalyst having a greater oxygen reduction over potential than platinum.

The invention discloses a preparation method of a ferro-nickel bi-metal hydroxide of a sheet structure on foamed nickel through in-situ growth, and belongs to the field of electrochemistry. Nickel nitrate hexahydrate, iron nitrate nonahydrate, urea, ammonium fluoride and foamed nickel are adopted as main raw materials, and an electrocatalyst through water electrolysis oxygen production is successfully prepared. The sheet structure of the catalyst supplies abundant active sites, due to existence of substrate foamed nickel, the electrical conductivity is enhanced, and when the hydroxide is adopted as the electro-catalysis oxygen production catalyst, the excellent catalysis activity is shown. The activity of a traditional non-noble metal material under an oxygen evolution reaction (OER) in analkaline electrolyte is not ideal. Accordingly, the OER catalysis performance of the non-noble metal material under the alkaline condition is improved, and the method is of great significance in solving the fossil fuel energy crisis. Nickel and iron earth reserve volumes are quite abundant, the OER catalytic performance of the ferro-nickel bi-metal hydroxide of the sheet structure under the alkaline condition is excellent, and the hydroxide is a catalytic material with the wide prospect.

The invention relates to a method for rapidly preparing a metal-organic framework (MOF) compound having a controllable structure by using an electrochemical method. After the method is adopted, an MOF material can be electrically synthesized on a variety of macroscopic and microcosmic conductive substrates by means of a simple and rapid one-step electrical synthesis method. Furthermore, the directional growth of multiple MOFs materials can be realized on different types of macroscopic and microcosmic conductive substrates by regulating and controlling the types, concentrations, proportions, electrical synthesis voltages, time and the like of organic ligands and metal ions in an electrolyte solution; the particle sizes and morphologies of the MOFs materials can be artificially regulated and controlled. The electrochemical synthesis method has the advantages of short synthesis time and simple operation process, synthesis can be completed under the condition of room temperature, and a condition for subsequent extensive preparation and industrial application is provided. In addition, the prepared novel MOFs thin-film material has a very wide application prospect in the aspects of electrolytic water oxygen evolution reaction (OER), supercapacitor electrode materials (SCs), lithium ion battery electrode materials, biosensing and the like.

The invention provides a method of partial vulcanization to improve oxygen evolution electrode performance of metal hydroxide and belongs to the field of oxygen evolution catalyzation of electrolysis of water. The method comprises the following steps: firstly, pretreatment is carried out on nickel foam, then, special nano floriform metal hydroxide is formed on the surface of the nickel base after the pretreatment in an in-situ growth manner through the hydrothermal synthesis method, and finally, the prepared metal hydroxide and a sulphur source have hydrothermal reaction to prepare a hydroxyl metal sulfide oxygen evolution electrode. According to the invention, the method is novel, the demanded technology is simple, the production cost is low, requirements to equipment are lower, and industrial production is suitable; in addition, the prepared electrode has excellent oxygen evolution activity and stability, is large in specific surface area, firmly combines with a base, and can be applied to the field of oxygen evolution through industrial electrolysis of water.

The invention relates to a hydroxyl oxidize iron-nickel-iron hydrotalcite integrated oxygen evolution electrode applicable to alkaline mediums and a preparation method and application thereof. The electrode is applicable to the oxygen evolution reaction in the water-electrolytic hydrogen making process under catalytic alkaline conditions. The hydroxyl oxidize iron-nickel-iron hydrotalcite integrated oxygen evolution electrode and the preparation method and application thereof have the advantages as follows: the nickel-iron hydroxide integrated electrode is shape-controlled, the preparation process is simple and under mild conditions, and the electrode can be used for a water electrolytic tank for hydrogen production from water splitting under external bias potentials; the prepared hydroxyloxidize iron-nickel-iron hydrotalcite integrated oxygen evolution electrode further has a better performance when being used in an alkaline solid polymer electrolyte (AEM) water electrolytic tank; and besides, an extensive utilization value in achieved in regenerative fuel cells (RFC), photoelectro-catalytic devices and electrolytic hydrogen generators.

The invention discloses an electrolyzed-water catalytic material with a nanometer core-shell structure of cobalt sulfide and molybdenum disulfide. The electrolyzed-water catalytic material is composed of a catalytic active material and a carrier, wherein the catalytic active material is a material with the nanometer core-shell structure of cobalt sulfide and molybdenum disulfide; molybdenum disulfide is a shell; cobalt sulfide is a core; and the carrier is ultrafine carbon fiber. The electrolyzed-water catalytic material provided by the invention has high specific surface area and porosity, is favorable for diffusion and gas desorption of electrolyte, has the characteristics of dual functions of hydrogen evolution and oxygen evolution at the same time, and can be directly used as an electrode for electrocatalytic hydrogen preparation without the need of loading onto the electrode.

The invention relates to an ultrathin nanosheet array electro-catalytic material with a nano-porous structure and oxygen vacancies. The material is a cobaltosic oxide primary nanosheet array which grows vertically on a conductive substrate and is doped with a metal; an ultrathin nanosheet with oxygen vacancies and nanopores is obtained on each primary nanosheet; the conductive substrate is a titanium sheet or a foamed nickel sheet, and the doped metal is zinc, nickel or manganese; and the thickness of each cobaltosic oxide ultrathin nanosheet doped with the metal is 1.22 nm, nanosheets are in a three-dimensional porous structure, and the nano-pore diameter is 3-6 nm. The ultrathin nanosheet array electro-catalytic material with the nano-porous structure and oxygen vacancies has the following advantages: the material can effectively reduce the overpotential and the spike potential of an oxygen evolution reaction, increase the conversion rate of a single cobalt atom and work continuously and stably in an alkali environment; the steps of a preparation method of the material are simple, the operation is convenient, the cost is low, and the material is environmental-friendly; and new ideas and strategies are provided for the function-oriented design and the performance optimization of an oxygen evolution catalyst of a water electrolysis system.

The invention relates to a non-metallic bi-functional oxygen catalyst for graphene/nickel iron type hydrotalcite as well as a preparation method and electric catalytic application thereof to oxygen evolution reaction and oxygen reduction reaction in an alkaline medium. The catalyst takes a micelle as a template, and under the hydrothermal and reducing conditions, the nickel iron type hydrotalcite is assembled onto graphene in sequence to form a spherical porous graphene oxide/nickel iron type hydrotalcite compound. The method comprises the following steps: dispersing graphene oxide and metal salt in the micelle, introducing an alkali source, synthesizing the graphene oxide/nickel iron type hydrotalcite compound under the hydrothermal conditions, and performing hydrazine hydrate reduction on an obtained product to obtain the catalyst. The catalyst prepared by the method has high oxygen evolution and oxygen reduction catalytic activity, good stability and excellent methanol tolerance under the alkaline conditions and is low in cost of raw materials used, simple in preparation method, easy to operate and convenient for large-scale production.

The invention relates to a nitrogen-sulfur double-doped carbon material difunctional oxygen catalyst, a preparation method thereof and electrocatalysis application of alkaline medium in oxygen. In the catalyst, ocean polysaccharide sodium alginate is used as a carbon source, thiourea is sources of nitrogen and sulfur atoms, and double doping is performed on N and S which have electronegativity by high-temperature calcination in an inertia atmosphere to obtain a nitrogen-sulfur double-doped carbon material electrocatalyst. Since a double-doped crystal structure of heteroatoms is changed, the specific area and the catalyst site of the catalyst are improved, meanwhile, relatively high oxygen evolution (OER) and oxygen reduction (ORR) catalytic activity are achieved, and the overoptential of OER and ORR is effectively reduced; the ORR process is most divided to four electron catalytic mechanisms and is an relatively ideal ORR reaction process, and the catalyst has favorable stability and excellent methyl alcohol resistance; and the used raw material is low in cost, the preparation method is simple and is easy to operate, and mass production is facilitated.

The invention belongs to the technical fields of material sciences and electro-catalytic hydrogen production, and particularly relates to a nickel-iron hydrotalcite based electro-catalytic oxygen evolution electrode and preparation thereof, wherein the nickel-iron hydrotalcite based electro-catalytic oxygen evolution electrode can be used in an electrolytic water oxygen evolution reaction in an alkaline medium. An electrode system takes a nickel-iron hydrotalcite structure as a catalytic activity center and takes nickel foam as an electrode material; in the alkaline medium, the nickel-iron hydrotalcite based electro-catalytic oxygen evolution electrode can efficiently electrolyze water to prepare oxygen, the overall overcurrent polishing of electrolytic water is reduced greatly, and good stability is showed; according to the preparation technology of the nickel-iron hydrotalcite based electro-catalytic oxygen evolution electrode, a nickel-iron hydrotalcite composite structure is grownon the nickel foam base through an in-situ electrodeposition method; and the resources of required raw materials are wide, the price is low, the technology is mature and stable, operation is easy, convenient and fast, controllability is high, the process does not produce poison, and the nickel-iron hydrotalcite based electro-catalytic oxygen evolution electrode is suitable for mass production andthe industrial electrolytic water reaction.

The invention belongs to the technical field of materials and energy sources and particularly provides a metal phosphide/graphite carbon hybrid material and a preparing method and application thereof. A cobalt base-metal organic framework (ZIF-67) is utilized as a template and directly reacts with red phosphorus through heating, and the cobalt phosphide/graphite carbon hybrid material with the strong interface coupling effect is prepared in an in-situ mode. The hybrid material is formed by uniformly distributing and embedding cobalt phosphide nanometer particles in a polyhedron graphite carbon matrix. When used in the oxygen evolution reaction as a catalyst, the hybrid material shows high catalytic activity. The synthetic method is easy to operate, low in production cost and capable of achieving large-scale preparation, and is a novel efficient and economic preparing method.

The invention discloses a metal-organic framework nanosheet as well as a preparation method thereof and application thereof in oxygen evolution reaction of electrolysis water. According to the preparation method, the energy consumption is low, the reaction is rapid, reaction conditions are mild, the thickness of the obtained metal-organic framework nanosheet is 3nm-5nm, the specific surface area can reach 450m<2>.g<1>, and the alkali resistance and the chemical stability are good. The metal-organic framework nanosheet can be prepared into an electrolysis water oxygen production electrode, and a particular ultra-thin sheet structure can be in well contact with the surface of the electrode, so that influences on mass transfer, diffusion and material resistance in the electrochemical oxygen production process are overcome, the initial oxidation potential can reach 1.42V, and the overpotential at 10mA/cm<2> can reach 250mV. By virtue of a 24-hour test, the oxygen production effect is still maintained above 99.6%, the activity, stability and price of the metal-organic framework nanosheet are superior to those of traditional noble metal RuO2, and extremely high actual application value is achieved.

The invention discloses a transition metal compound (including phosphide, sulfide, selenide and nitride) nano array which is applied to low-energy-consumption electrochemical hydrogen production as a small-molecule electrooxidation and water-electricity reduction difunctional catalytic electrode and belongs to the fields of hydrogen energy and fuel cells. According to the transition metal compound nano array, the difunctional non-noble-metal array catalytic electrode is applied to small-molecule electrooxidation and water-electricity reduction simultaneously for the first time; an electrochemical oxygen evolution reaction is replaced with a small-molecule electrooxidation reaction low in oxidation potential, and a double-electrode electrolysis system based on the difunctional catalytic electrode is constructed; low-energy-consumption and stable electrochemical hydrogen production is achieved; and the transition metal compound nano array is applicable to large-scale industrial hydrogen production.

The invention belongs to the technical field of water electrolysis, and particularly relates to a two-step method and device for producing hydrogen through water electrolysis on the basis of a three-electrode system. According to the device, an electrolytic bath comprises a hydrogen evolution catalysis electrode, an oxygen evolution catalysis electrode and a nickel hydroxide electrode. According to the method, water molecules are electrochemically reduced to hydrogen gas on the surface of the hydrogen evolution catalysis electrode, a Ni(OH)2 electrode is electrochemically oxidized to form a NiOOH electrode at the same time, and electrons flow to the hydrogen evolution catalysis electrode from the Ni(OH)2 electrode through an external circuit in the process; the NiOOH electrode is electrochemically reduced to the Ni(OH)2 electrode, hydroxyl ions are electrochemically oxidized to form oxygen gas on the surface of the oxygen evolution catalysis electrode, and the electrons flow to the NiOOH electrode from the oxygen evolution catalysis electrode through the external circuit in the process. According to the device and the method, the hydrogen production step and the oxygen production step which are synchronous in conventional water electrolysis are effectively separated, the high-purity hydrogen gas can be prepared without any diaphragms through the electrolysis device because the hydrogen production step and the oxygen production step are completely separated, and therefore the cost of producing the hydrogen through water electrolysis is lowered further.

The invention belongs to the technical field of water electrolysis and particularly relates to a three-electrode system double-electrolytic bath two-step water-electrolytic hydrogen producing device and method. The electrolysis device comprises two independent electrolytic baths 1 and 2, a hydrogen evolution catalyzing electrode, an oxygen evolution catalyzing electrode, a nickel hydroxide electrode and an alkaline electrolyte. According to the electrolysis device, the water electrolysis process is divided into two steps of hydrogen production and oxygen production which are respectively and alternately carried out in the two electrolytic baths 1 and 2. The device has the advantages that the steps of hydrogen production and oxygen production which are simultaneously generated in conventional water electrolysis can be effectively separated and respectively completed in different electrolytic baths, so that high-purity hydrogen can be produced under the condition of adopting no diaphragm and the water-electrolytic hydrogen producing cost is further reduced.

The invention relates to a preparation method of a carbon-coated cobalt oxygen evolution reaction electro-catalyst and belongs to the preparation field of electrochemical catalysts. The preparation method includes the steps that firstly, a carbon source and cobalt salts in proportion are placed into water for dissolving and mixing, and then evaporation to dryness is performed at the water bath condition at the temperature of 50 DEG C-80 DEG C to obtain powder evenly mixed; then the powder is heated to 400 DEG C-1000 DEG C under the shielding gas condition and then calcinated for 30 minutes-120 minutes to obtain a carbon-coated cobalt elementary substance; finally, an electrochemical pretreatment method is used for obtaining a nano-particle of carbon layer-cobaltic oxide-elementary substance cobalt, wherein the nano-particle is of an electric conduction core-shell structure. The method is simple in process, convenient to implement and low in requirement for preparation equipment and improves safety in the experiment process. The carbon layer-cobaltic oxide-elementary substance cobalt prepared through the method is even in diameter and good in electric conduction and has good electro-catalysis water oxidation performance.

The invention discloses supported nickel-iron composite hydroxide oxygen evolution electrode for alkaline water electrolysis and a preparation method for the supported nickel-iron composite hydroxide oxygen evolution electrode. The preparation method comprises the following steps: performing easy physical mixing-rolling on nickel and iron salt solutions, a conductive carrier and a binder to directly obtain a metal salt/carbon film; and performing low-temperature thermal treatment, in-situ precipitation and metal current collector pressing to obtain the supported nickel-iron composite hydroxide oxygen evolution electrode. Through the in-situ precipitation reaction of a metal salt pre-absorbed in the carrier, the dimension of a nickel-iron composite hydroxide catalyst is controlled, and an active site is improved; and secondly, through the in-situ precipitation reaction process, negative ions of a nitrate radical, a sulfate radical and the like are easily inserted into a nickel-iron composite hydroxide lattice, so that the oxygen evolution activity of the electrode is further regulated; moreover, the resistance loss is reduced through an internal structure constructed by the conductive carrier with a high specific surface area. The preparation method for an electrode material has the advantages of being simple, gentle in condition and high in raw material utilization rate, so that the good industrial prospect and a high economic value are shown.

The invention provides a self-supporting transition metal-phosphorus alloy catalyst, and a preparation method and an application thereof, and belongs to the field of alkaline electrolytic bath water decomposition. The preparation method of the catalyst comprises the following steps: mixing the salt of a transition metal element with a phosphorus source, and adding a surfactant or an alkaline solution to obtain an electrolyte; and electrodepositing in the electrolyte with a transition metal conductive substrate as a working electrode in order to obtain the self-supporting transition metal-phosphorus alloy catalyst. The invention also provides the self-supporting transition metal-phosphorus alloy catalyst prepared through the preparation method. The self-supporting transition metal-phosphorus alloy catalyst has excellent electrocatalytic hydrogen evolution and oxygen evolution performances in electrolytic baths.

The invention discloses a NiFe3N/NF electrochemical catalyst and a preparation method and an application thereof. The electrochemical catalyst is derived by treating a dual-MOF (dual-metal-organic framework) with heat, K4Fe(CN)6 is adopted as a ligand, the ligand contains Fe to provide an Fe source, and by combining a complexing agent ligand with central metal Ni, the dual-MOF is formed; in-situ synthesis is carried out on an Ni substrate, not only is the electric conductivity of the Ni substrate utilized, but also the resistance between the MOF and the Ni substrate is decreased by in-situ synthesis, the dual-MOF is synthesized in one step, and the porosity of the MOF is utilized; moreover, after alkali metal salt is utilized for wrapping, the MOF is treated by heat, and thereby the morphology of the MOF is kept. The process of the preparation method disclosed by the invention is simple, the material cost is low, the preparation method is easy to operate, moreover, the repeatability is high, and the prepared NiFe3N/NF electrochemical catalyst is used for electrocatalytic oxygen evolution reaction.

The invention discloses a ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode and a preparation method and application thereof. The preparation method comprises the following steps: firstly, depositing bismuth oxyiodide on the surface of conductive glass, then coating the surface with the deposited bismuth oxyiodide with a dimethyl sulfoxide solution of vanadyl acetylacetonate, annealing, performing alkali soaking and rinsing with water to remove excessive vanadium pentoxide, and then drying to obtain a bismuth vanadate photoelectrode, and modifying ferro-nickel oxyhydroxide on the surface of the bismuth vanadate photoelectrode by adopting a cyclic voltammetry method in a three-electrode system, thus obtaining the ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode. The invention further discloses applications of the ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode in photoelectrocatalytic decomposition water. The prepared photoelectrode is used for producing hydrogen from photoelectrocatalytic decomposition water, can inhibit the compounding of photon-generated carriers, the service life of carriers generated by a BiVO4 photoelectrode can be effectively prolonged, and the oxygen evolution reaction on the surface of the photoelectrode can be promoted, so that the solar optic hydrogen conversion efficiency of a semiconductor photoelectrode can be improved.

The invention discloses an oxygen reduction and oxygen evolution Co2P@NPC double-function compound catalyst and a preparation method and application thereof. The compound catalyst comprises N-P-codoped carbon layer coated Co2P nano rods and/or nano particles. The preparation method includes: evaporating and drying the solution of cobalt acetate, concentrated phosphoric acid and urea, and performing high-temperature treatment under protective atmosphere to obtain the compound catalyst. The preparation method has the advantages that the method is simple, low in cost and beneficial to industrial production; the prepared oxygen reduction and oxygen evolution Co2P@NPC double-function compound catalyst is applicable to fuel cell and water decomposition, high in activity and good in stability, the catalytic performance of the compound catalyst is close to that of a commercial precious metal 20wt% Pt/C and RuO2 catalyst, and the compound catalyst is promising in application prospect.