44results about How to "Excellent OER performance" patented technology

The invention discloses an in-situ composite electrode of a nitrogen-phosphorus co-doped carbon nanotube coated ferrocobalt bimetallic alloy catalyst and preparation method thereof, and application ofin-situ composite electrode. The preparation method comprises the following steps of: preparing an in-situ flaky MOF precursor on a carbon paper substrate; dipping the carbon paper on which the MOF precursor grows into a ferrous sulfate solution, and obtaining iron-containing MOF in the cation exchange process of the aqueous solution; after drying, putting the iron-containing MOF into a reactionkettle containing a phosphorus source, and performing heating to achieve gas-phase phosphorus doping; and in Ar gas flow or N2 gas flow, discharging urea for annealing and in-situ preparation of the carbon nanotubes. The product obtained by the technical scheme provided by the invention constructs a variety of high electrocatalytic active sites, and includes metal particles coated at the top end of a carbon nanotube and nitrogen-phosphorus co-doped carbon active sites. The in-situ composite electrode provided by the invention has the excellent and stable three-function catalytic activity of HER, OER and ORR.

The invention discloses a preparation method of a dodecahedral hollow cobalt-nickel selenide/iron oxyhydroxide composite catalyst, and can solve the problems of high price, poor stability and the likeof noble metal electrode materials. The preparation method comprises the following steps: mixing cobalt nitrate hexahydrate, dimethylimidazole and methanol, and conducting stirring at room temperature to obtain ZIF-67; mixing the obtained material, nickel nitrate hexahydrate and ethanol, and conducting stirring at room temperature to obtain CoNi-LDH; carrying out selenylation treatment on the obtained material and selenium powder by adopting a chemical vapor deposition method to obtain (Co,Ni)Se2/C; and subjecting the obtained selenide and ferrous sulfate heptahydrate to a chemical water bathdeposition method, so as to obtain (Co,Ni)Se2/C-coated FeOOH. According to the invention, the cobalt-nickel-based selenide/iron oxyhydroxide composite material with the hollow cage-shaped nano structure is prepared by a simple and convenient chemical water bath deposition method, and the material shows excellent electrochemical properties such as relatively low overpotential, good stability and the like in an oxygen evolution reaction.

The invention relates to a preparation method of a porous nickel-molybdenum-based nanosheet difunctional electrocatalyst, and belongs to the technical field of electrochemical electrode materials. Specifically, foamed nickel is used as a matrix, a hydrothermal method and subsequent heat treatment and phosphorus doping are utilized to prepare the porous nickel-molybdenum-based nanosheet difunctional electrocatalyst material, the reaction temperature is 300-360 DEG C, the reaction time is 1.5-2.5 h, and the heating rate is 1.5-2.5 DEG C/min; the phosphorus-doped porous NiMoO4 nanosheet is obtained; the electrode is directly used as a working electrode, and the working electrode has excellent difunctional electrocatalytic performance; improvement of OER catalytic activity can be attributed toformation of a porous structure, and improvement of HER catalytic activity can be attributed to optimization of an electronic structure caused by P doping and the porous structure.

The invention discloses a dual-functional electrocatalyst Pt-IrO2 and a preparation method. Chloroplatinic acid and chloroiridic acid are used as a precursor solution, a Pt-IrO2 nanowire catalyst is obtained by an electrostatic spinning method, the catalyst carrying capacity is reduced, and meanwhile, the active area is effectively expanded. The preparation process is simple to operate, the Pt andIrO2 proportion in the catalyst is good in adjustability, other additives are not needed to be added, no leakage and no corrosion exist, and the preparation process is simple to operate, is good in repeatability, is suitable for industrial production on a large scale and has a wide prospect in the field of electrolysis water. The preparation method comprises the following steps of (1) preparing aPVP solution; (2) adding the chloroplatinic acid and the chloroiridic acid into deionized water to form a solution; (3) adding the PVP solution after the chloroplatinic acid and chloroiridic acid solution is mixed according to a certain proportion, and performing magnetic stirring to form a spinning precursor; (4) performing electrostatic spinning under a certain condition; and (5) sintering to obtain the Pt-IrO2 nanowire catalyst.

The invention discloses a method for growing an MOF material at the surfaces of bacteria by using bacteria as a template and converting the MOF material into a multi-stage porous carbon material. Themethod includes the following steps: (1) dispersing bacterial powder into a precursor solution, sequentially adding an organic ligand and a soluble metal salt, performing uniform mixing, and allowingthe mixture to stand in a sealed manner for 12-24 h; and (2) centrifuging and washing the solution after standing, drying the obtained precipitate, performing carbonization, and performing grinding toobtain the multi-stage porous carbon material. The invention also discloses the multi-stage porous carbon material prepared by the method, and a lithium-sulfur battery and a zinc-air battery preparedfrom the multi-stage porous carbon material. The preparation method for the multi-stage porous carbon material provided by the invention uses the bacteria as the biological template and a part of carbon sources, uses the bacterial structure combined with the porous MOF material to construct the multi-stage porous carbon material, and is extremely simple and effective.

The invention relates to the field of novel two-dimensional material preparation, in particular to a preparation method of an alpha-NixFey(OH)2 electrocatalyst and application of the alpha-NixFey(OH)2electrocatalyst to a working electrode. According to the method for rapidly preparing an iron-doped alpha phase nickel hydroxide porous nanosheet (alpha-NixFey(OH)2) material by using sodium borohydride as a foaming agent and a coprecipitator, the working electrode is prepared from an iron-doped alpha phase nickel hydroxide porous nanosheet, and the working electrode has the excellent oxygen evolution performance. Thus, by using NaBH4 as the foaming agent and the coprecipitator, the iron-doped alpha phase nickel hydroxide porous nanosheet material (alpha-NixFey(OH)2) is rapidly prepared, andthe excellent OER performance is achieved; and improvement of the catalytic activity can be attributed to the strong electron interaction between Ni and Fe and the porous structure.

The invention relates to the technical field of energy material synthesis, and discloses a double-defect ultrathin metal organic framework nanosheet catalyst, a preparation method and application thereof. The preparation method comprises the steps of: dissolving 2, 6-naphthalic acid and naphthoic acid in a solvent, adding a nickel salt and an acid-binding agent into the solvent, subjecting the obtained solution to ultrasonic stripping and light treatment, and then conducting washing and separation to obtain the catalyst; the catalyst has an ultrathin nanosheet structure and a larger specific surface area, so that more catalytic active sites are exposed, the reaction energy potential barrier can be reduced, and the catalytic performance is improved. When the catalyst is applied to electrocatalytic water oxygen evolution reaction, electrochemical decomposition of water for oxygen evolution can be quickly realized under the condition of low energy consumption, and meanwhile, the catalyst has relatively good catalytic stability.

The invention belongs to the technical field of electro-catalysis, and particularly relates to a preparation method of an iron-nickel electro-catalyst and an oxygen evolution application thereof underhigh current density. Cheap ferric nitrate is used as a main raw material of the catalyst, ultrathin Fe and Ni nano sheets can grow on foamed nickel in-situ only through a simple hydrothermal reaction for 3 hours, and the average thickness of the obtained nano sheets is only 4.5 nm, so that the catalyst has an ultra-large specific surface area, and rich active sites are exposed. The preparation process of the catalyst is simple, the raw materials are cheap and easily available, and the production cost is greatly reduced. Meanwhile, the catalyst shows excellent oxygen evolution performance under an alkaline condition; over-potentials of 195 mV, 280 mV and 307 mV can drive current density of 10 mA/cm<2>, 500 mA/cm<2> and 1000 mA/cm<2>, meanwhile, the catalyst can stably operate for at least80 hours under a current density of 1000 mA/cm<2>, and the catalyst is an excellent catalyst meeting actual industrial production conditions.

The invention provides a preparation method of a Ru nano-material with different morphologies and application of the preparation method. The preparation method of the Ru nano-material with the different morphologies comprises the steps that (1) a Ru source is added into ethylene glycol for sufficient and uniform stirring; (2) then different gas is introduced, and reaction, cooling, washing and drying are carried out under 120-200 DEG C; and (3) an obtained catalyst and carbon black are mixed uniformly, drying is carried out after uniform ultrasound, then thermal treatment is carried out to obtain Ru/C, and the Ru/C is used for an electrochemical performance test. Ru is uniformly distributed on the carbon black, and Ru presents a shape of a nanowire, a nano sheet clip and nano-particles; the OER performance of the Ru nanowire, the nano sheet clip and the nano-particles greatly exceeds industrial RuO2 and industrial IrO2 catalysts under the acidic condition, and voltages corresponding tothe electric current density of 10mA/cm<2> of the OER performance of the Ru nanowire, the nano sheet clip and the nano-particles separately reach 224mV, 286mV and 252mV (vs.RHE) under the acidic condition. The catalyst has good stability under the acidic condition. The preparation method of the Ru nano-material with the different morphologies is simple, the catalyst has higher activity and stability, and a better application prospect is achieved on the aspect of electrolysed water.

The invention discloses a controllable synthetic lanthanum-doped cobalt oxide nanosheet and a preparation method and application thereof, and belongs to the field of nanometers. The lanthanum-doped cobalt oxide nanosheet is of an irregular monodisperse sheet structure, and the main elements of the lanthanum-doped cobalt oxide nanosheet are La, Co and O, wherein La, Co and O are uniformly distributed at the hexagonal edges. The lanthanum-doped cobalt oxide nanosheet has the excellent OER performance which is superior to the performance of IrO2 sold in the market at present. The nanosheet employs the hydrothermal solvent method, and is obtained through a drying oven program temperature control mode. The nanosheet is simple in process, is low in reaction temperature, is high in yield, is suitable for the batch production, and is of important guiding significance to the development of the renewable energy technology.

The invention discloses a preparation method of an iron-doped cobalt imidazolate nano catalytic material, which comprises the following steps: fully dissolving a proper amount of cobalt nitrate, ferric nitrate, an organic ligand and an organic acid in an organic solvent, and fully conducting stirring at 70 DEG C to obtain a mixed reaction solution; 2) transferring the mixed reaction solution into a high-pressure reaction kettle, and preserving heat until the reaction is complete; and 3) after the high-pressure reaction kettle is cooled to room temperature, centrifugally conducting washing to obtain a brown precipitate, and purifying the brown precipitate to obtain the iron-doped cobalt imidazolate nano material.

The invention discloses a nickel/molybdenum selenide bifunctional composite catalyst and a preparation method and application thereof, and belongs to the technical field of new energy materials and electrochemical energy storage. Foamed nickel is washed with diluted hydrochloric acid, deionized water and absolute ethyl alcohol, then selenium dioxide, sodium molybdate and nickel acetate are dissolved in the deionized water, and a precursor sample is prepared in a standard three-electrode system by taking a graphite rod as a counter electrode, taking the foamed nickel as a working electrode and taking silver/silver chloride as a reference electrode through a simple electro-deposition method; and after electro-deposition is finished, the prepared precursor sample is washed with the deionized water and is dried, and the nickel/molybdenum selenide bifunctional composite catalyst is obtained. The low-cost and efficient nickel/molybdenum selenide bifunctional electrocatalyst is prepared through simple electrodeposition, and the material shows low overpotential and good stability in a hydrogen evolution reaction and an oxygen evolution reaction and is suitable for application and popularization.

The invention discloses a foamed nickel-based Nano-K2Fe4O7 catalyst, a preparation method and application of the foamed nickel-based Nano-K2Fe4O7 catalyst in the aspect of efficient electrocatalytic hydrolysis, and belongs to the field of electrocatalytic material preparation technologies and application. The preparation method comprises the following steps: firstly, ultrasonically treating a substrate material with 2mol of diluted hydrochloric acid for 8-15 minutes, then respectively washing with deionized water and ethanol for several times, and drying for later use; and then adding the dried substrate material into a reaction system of K2Fe4O7 to carry out hydrothermal reaction, and drying to obtain the foamed nickel-based Nano-K2Fe4O7 catalyst disclosed by the invention. Experimental results show that the Nano-K2Fe4O7 prepared by the preparation method disclosed by the invention can output very large current (the current density is greater than 2000mA/cm < 2 >) in the OER and HER processes; and moreover, the stability can be kept for a long time (60 hours) when high current density (about 1500mA/cm < 2 >) is output, the preparation of a large-scale electrode material can be carried out, and the application of large-scale electro-catalytic hydrolysis is expected to be realized.

The invention belongs to the technical field of new energy materials, and particularly relates to a preparation method of a CoO-coated carbon nanotube film with HER/OER bifunctional catalytic activity, which is characterized by comprising the following steps: under a hydrothermal condition, growing an MOF precursor on the surface of each nanotube in a carbon nanotube film subjected to surface pretreatment, and then conducting carbonizing to obtain the electrode material with HER and OER dual-catalytic activity. The material has excellent HER and OER dual-catalytic activity and stable performance. The preparation method provided by the invention has the advantages of low raw material cost, simple preparation method, environmental friendliness and easiness in large-scale production, and overcomes the defect that the existing HER catalyst is high in preparation cost and difficult to meet industrial application.

The invention belongs to the field of nanometer, particularly belongs to the application of nanometer materials in renewable energy technologies, and more particularly relates to an optimization method of layered sulfide nanocrystals and an optimized Sn-S-Co nanocrystal composite material, and the crystal form of the sulfide nanocrystals can be remarkably improved by performing controllable phosphorization on the sulfide nanocrystals. Therefore, the OER performance of the material can be remarkably improved, and the OER application of the material serving as a catalyst in an efficient catalytic fuel cell is further improved. Through detection, the performance of the material is excellent and is superior to that of IrO2 sold in the market at present, and the material has important guiding significance for renewable energy technology development.

The invention discloses a core-shell chain-shaped nickel-based selenide/iron oxyhydroxide composite catalyst as well as a preparation method and application thereof, and belongs to the technical field of new energy materials and electrochemical energy storage. The preparation method comprises the following steps: mixing nickel acetylacetonate (II), ethylene glycol and hydrazine hydrate, and performing hydrothermal reaction to prepare a nickel nano chain material; then adding the Ni3Se4 porous nanochain material into a mixed solution of selenium powder, sodium hydroxide, N, N-dimethylformamide and hydrazine hydrate, and performing heating and reacting to obtain the Ni3Se4 porous nanochain material; dispersing the obtained Ni3Se4 porous nano chain material in deionized water, adding ferrous sulfate, performing stirring, and performing heating reaction at 50 DEG C to obtain the Ni3Se4@FeOOH porous nano chain. The invention discloses a core-shell chain-like nanostructured nickel-based selenide/iron oxyhydroxide composite catalyst prepared by a simple chemical hydrothermal method, and the catalyst shows excellent electrochemical properties such as lower overpotential and good stability in oxygen evolution reaction, and is suitable for popularization and application.

The invention provides a Fe-doped novel two-dimensional Co-MOFs composite material as well as a preparation method and application thereof. The composite material takes a novel two-dimensional Co-MOFs crystal material as a carrier, an Fe element is doped and distributed on the carrier, and after the Fe element is doped in a Co-based metal organic framework material with a two-dimensional framework crystal structure, the obtained composite material has an amorphous structure, and the Co element and the Fe element are uniformly distributed in the amorphous structure. The composite material has good electrochemical catalysis oxygen evolution performance under alkaline conditions, is still stable after 11 hours of circulation, and can be used as an alkaline OER electrocatalyst.

The invention provides a preparation method of Ce-Co-S-P nanocrystals. The method comprises the following steps: mixing ceric ammonium nitrate, cobalt acetylacetonate, oleic acid, n-dodecanethiol and tri-n-octylphosphine, heating to 320 DEG C, carrying out heat preservation reaction, and carrying out dispersion sedimentation and centrifugal separation on the obtained product to obtain the Ce-Co-S-P nanocrystals. The Ce-Co-S-P nanocrystals prepared in the invention have excellent OER performance, and can efficiently catalyze OER in a fuel cell. A one-pot method is adopted, Ce is used for effectively adjusting the phase change of Co-S-P nanosheets, meanwhile, the catalytic performance is adjusted, the process is simple, the reaction temperature is low, the reaction time is short, the method is suitable for batch production, and the method has important guiding significance on renewable energy technology development.