746 results about "Metal nitrate" patented technology

The invention discloses a preparation method of a catalyst with a core-shell structure for a low-temperature fuel cell, belonging to the technical field of fuel cells. In the catalyst with the core-shell structure prepared with the preparation method, platinum is taken as a shell, a metal alloy consisting of more than one of metals including ruthenium, platinum, iron, cobalt, nickel, copper, tin, iridium, gold and silver is taken as an inner core, and the shell and the inner core are loaded on a carbon carrier. The preparation method comprises the following preparation steps of: reducing a metal chloride or a metal nitrate with a reducing agent, and forming a core on the carbon carrier with a large specific surface area; stabilizing the core; and precipitating Pt on a core layer with a impregnation reduction method, a high-pressure organic sol method, a microwave method or an electrodeposition process to form the catalyst with the core-shell structure. Due to the adoption of the preparation method, the utilization ratio of noble metal platinum is increased, the cost of an electro-catalyst is reduced effectively, and the methanol oxidizing capability and oxygen reducing activity of the obtained catalyst are increased by 10.8 times and 8.7 times in maximum respectively in comparison to the mass ratio and activity of a commercial JM4100Pt/C catalyst.

A material for a pyrotechnic composition and related pyrotechnic compositions are provided in which the material includes a substituted basic metal nitrate including a reaction product of an acidic organic compound and a basic metal nitrate. A method for enhancing a burn rate of a gas generant composition and a burn rate enhanced gas generant composition including a reaction product of basic metal nitrate and tetrazoles, tetrazole derivatives, and combinations thereof, and a nitrogen-containing co-fuel such as guanidine nitrate are also disclosed. The burn rate enhance gas generant composition may optionally include an additional oxidizer such as basic copper nitrate.

The invention discloses a preparation method of a lithium ion battery negative electrode material spinel porous high-entropy oxide material, and belongs to the field of inorganic oxide powder materials. The method is a low-temperature combustion synthesis method, and specifically includes the steps that metal nitrate is adopted as a metal source, one or a mixture of several of tartaric acid, citric acid, glucose, hexamine and ethylenediaminetetraacetic acid is used as a fuel, and by controlling the concentration of the metal salt raw material, the kind and the amount of the fuel, the kind andthe amount of a combustion improver and an ignition mode, characteristics of the grain size, the shape and the like of spinel ransition metal high-entropy oxide nano-powder are adjusted and controlled. According to the preparation method of the lithium ion battery negative electrode material spinel porous high-entropy oxide material, liquid-phase ingredients are adopted, molecular-level even mixing of the raw materials is ensured, and a stoichiometric ratio of the product is achieved; meanwhile the preparation method of the lithium ion battery negative electrode material spinel porous high-entropy oxide material has the advantages of being energy-saving, high in production efficiency, environmentally friendly, free from complex post-treatment and the like, and the prepared high-entropy oxide powder is high in purity, small in grain size and even in distribution, and has high initial discharge capacity and good cycle performance.

Belonging to the field of inorganic oxide powder materials, the invention discloses a preparation method of a spinel-type porous high entropy oxide material. The method is low temperature combustion synthesis method. Specifically, a metal nitrate is adopted as the metal source, one of or a mixture of several of citric acid, ethylenediamine tetraacetic acid, hexamethylenetetramine and glucose is adopted as the fuel, by controlling the concentration of the metal salt raw materials, the fuel type and adding amount, the combustion improver type and adding amount, and the ignition way, the granularity, morphology and other characteristics of the spinel-type transition metal high entropy oxide (CoCrFeMnNi)3O4 nanopowder can be regulated. The preparation method adopts liquid phase compounding toensure molecular level uniform mixing of the raw materials, and the product achieves stoichiometric ratio. At the same time, the method has the advantages of energy saving, high production efficiency,green and environmental protection, no need for complicated post-treatment and the like. The high entropy oxide powder prepared by the method provided by the invention has high purity and uniform particle size distribution.

The invention discloses a catalyst used for alcoholysis of urea for synthesizing propylene carbonate and preparation and application methods thereof. The catalyst consists of mixed metal carbonate of Pb-Zn, Pb-Mg, Pb-Cr, Zn-Mg, Zn-Cr or Mg-Cr, and is prepared by performing coprecipitation reaction on corresponding metal nitrate mixed solution and excessive sodium carbonate solution. The application method of the catalyst is that: the reaction pressure is the natural pressure, the reaction temperature is between 140 and 180 DEG C, the reaction time is 2 to 8 h, a molar ratio of a reactant urea and 1,2-propylene glycol is 1:1-1:20, and the adding amount of the catalyst is 0.5 to 6 weight percent. The catalyst has the advantages of high catalytic activity, low cost, long service life, simple process in the application process, environmental friendliness, mild reaction condition, small using amount of the 1,2-propylene glycol, high yield of the propylene carbonate and cheap and readily available raw materials, is easy to prepare and reaction can be performed at normal temperature and the like.

The invention provides a method for preparing an alligatored surface of a light-emitting diode by using PS spheres as template. The method comprises the following steps: (1) performing epitaxial growth according to the conventional method to prepare an epitaxial wafer; (2) paving a layer of one-layer film which comprises closely packed PS spheres on the P-type contact layer obtained through epitaxial growth; (3) mixing precursor which is tetraethyl silicate, metal chloride or metal nitrate with ethanol and water to fill in the gap of the PS spheres of the one-layer film and the P-type contactlayer, standing at room temperature, heating to decompose the mixture and obtain the related oxides; (4) placing the epitaxial wafer in dichloromethane to dissolve the PS spheres, preserving the formed oxides in the gap of the PS spheres and the P-type contact layer on the P-type contact layer according to bowl-shaped periodic arrangement structure; (5) using the formed oxides as mask to perform dry etching on the P-type contact layer and obtain the alligatored surface; and (6) corroding and removing the residual oxides. The invention can be used to prepare the alligatored surface of the light-emitting diode with controllable etching period and depth.

A carried non-crystal Pd alloy catalyst for hydrogenating anthraquinone to prepare H2O2 is prepared from the carrier which is one or two of gamma-Al2O3, alpha-Al2O3, MgO, activated carbon, molecular sieve and mullite, non-crystal PdB alloy and RE element through immersing the carrier in the solution of RE metal's nitrate under ultrasonic condition, calcining at 400-700 deg.C for 2-5 hr, immersing in PdCl2 solution, dropping KBH4 solution in ice water bath, and washing. Its advantages are high catalytic activity and low cost.

The invention relates to a method for synthetizing a tungstate/tungsten oxide heterojunction photocatalyst in situ. The method comprises the following steps that WO3 is prepared or externally purchased to serve as a carrier; 2, a metal nitrate solution is prepared; 3, the WO3 is dipped in the metal nitrate solution; 4, bath drying and roasting are performed on a mixture obtained in the step 3, metal nitrate is decomposed to obtain a metal oxide (MO) in the roasting process, the MO reacts with the WO3 to generate MWO4, the MWO4 is loaded on the WO3 carrier in situ, and the MWO4/WO3 hetorojuncton photocatalyst is formed. According to the method, the MWO4/WO3 hetorojuncton photocatalyst is synthetized in situ, the used raw materials are low in cost, the preparation process is easy to operate, the high pressure condition and special equipment are not needed, the technology is simple, and the preparation cost is low.

The invention provides a metal supported MOFs catalyst as well as a preparation method and application thereof to PMDPTA synthesis and specifically relates to the technical field of catalysts. The catalyst comprises a carrier and an active component; the carrier is an MOFs material; and the active component is single metal or a composite metal particle. The catalyst is prepared by using an excessimpregnation method comprising the steps: stirring at least one solution in metal chloride or metal nitrate and the MOFs material at room temperature for 24h, and carrying out suction filtration to obtain a catalyst precursor; and making the catalyst precursor and a reducing agent generate an effect to obtain the metal supported MOFs catalyst. The preparation method of the catalyst has the advantages such as simple preparation process and stable structure. The catalyst is used for synthesizing PMDPTA and has the advantages such as low cost, high product yield, greenness and environment friendliness.

The invention discloses nanostructure tungsten alloy and a preparation method thereof. The alloy mainly comprises tungsten, and also comprises 0.05 to 1.0wt percent of zirconium and 0.2 to 2.0wt percent of rare-earth metal oxide particles, wherein the rare-earth metal oxide particle adopts yttrium oxide particles, lanthanum oxide particles or cerium oxide particles distributed in tungsten crystal particle. The method comprises the steps of firstly preparing ammonium paratungstate, rare-earth metal nitrate, citric acid and deionized water into transparent mixed liquor, stirring the transparent mixed liquor, obtaining gel after reaction, heating and drying the gel, then calcining the gel, so as to obtain a mixed powder of tungsten oxide and rare-earth metal oxide, putting the mixed powder into hydrogen atmosphere, so as to obtaining a mixed powder of tungsten and rare-earth metal oxide after reduction reaction, mixing the mixed powder with zirconium and zirconium hydride powder, so as to obtain a mixed powder of tungsten, zirconium, or zirconium hydride, and rare-earth metal oxide, and finally performing compaction and sintering to the mixed powder, so as to obtain the nanostructure tungsten alloy. The nanostructure tungsten alloy can be applied to fields of lighting, high-temperature components, aerospace devices, high temperature resistance containers and the like.

The invention provides a composite rear earth pyrochlore-type oxide catalyst for catalyzing burning for removing soot of a diesel vehicle and a preparation method thereof, belonging to the technical field of a tail gas cleaning catalyst of the diesel vehicle. The expression formula of the composite metal oxide is A2B2-xMxO7, wherein A is La, B is Sn, M is Mn, Fe, Co, Ni or Cu. The invention adopts a coprecipitation method to prepare the catalyst, the preparation process is simple, and the cost is low. The preparation method comprises the following steps: mixing metal nitrate and tin tetrachloride solution; adjusting the pH value by ammonia solution; drying the obtained deposit; and roasting the deposit at the high temperature to obtain the composite rear earth pyrochlore-type oxide catalyst. Under the effect of the catalyst, a simulation diesel vehicle exhausts, the burning temperature of the soot particles is lowered to the exhaust range of the diesel vehicle, and the speed of the soot oxidation rate is improved. The catalyst is a useful catalyst for removing the pollution of soot particles of the diesel vehicle.

The invention provides a preparation method of LDHs (magnesium-based layered double hydroxides). According to the method, calcium oxides or calcium magnesium oxides are used as an alkali source, calcium oxides or calcium magnesium oxides and a magnesium salt are subjected to a precipitation reaction, magnesium hydroxide precipitates are produced, then the magnesium hydroxide precipitates and divalent and trivalent soluble metal nitrates or chlorides are used as raw materials, LDHs are prepared through a liquid-solid phase reaction, and byproducts, namely, magnesium chlorides or magnesium nitrates, can be used as raw materials. The method has the advantages that the raw materials are rich in source, the price is low, the preparation process is simple, reaction conditions are mild, industrial production is facilitated and the like, and prepared LDHs can be widely applied to fields of catalysis, adsorption, environmental protection, high-polymer plastic and the like.

A gas generating composition for an air bag having a low toxicity, a high burning rate and a low combustion temperature is provided. It is a gas generating composition comprising (a) a triazine derivative, (b) a basic metal nitrate, and (c) a binder or (c) a binder and (d) an additive.

The invention provides a preparation method of novel doped black titanium dioxide. The method comprises the following steps: (1) a titanium oxide precursor is hydrolyzed, and after full washing, drying is carried out; (2) hydrolysate as well as metal nitrate, sulfide, fluoride, nitride and the like are fully mixed, and the materials are calcinated in an atmosphere furnace or a vacuum furnace at 300-800 DEG C for 2-15 hours. The products are fully washed and dried in order to obtain the doped black titanium dioxide. Doping with Fe, Mn, Sn, Ce and other metal cations as well as N, S, F and other anions are suitable for the method, the application range is wide, the process is simple, the cost is low, and the reaction conditions are simple.

The invention belongs to the field of chemical engineering and relates to a preparation method of a spinel type material, in particular to a method for preparing a spinel-type complex oxide through co-precipitation, homogenization and spray drying. According to the method, a mixed solution of two metallic nitrates and an alkaline solution are combined and added to a precipitation tank for a reaction, an obtained material is washed by deionized water, filtered, subjected to beating and refined by a homogenizer and then is sent to a spray drying machine, the dried material is subjected to calcination, and the spinel-type complex oxide powder is obtained. The method has the advantages of low calcination temperature, short time and low energy consumption, and a product has low loss, high purity and small particle size.

The invention discloses a mesoporous metal oxide catalyst for photo-catalytic CO2 reduction and a preparation method. The mesoporous metal oxide catalyst for the photo-catalytic CO2 reduction consists of an active component and a doping agent, wherein the active component is mesoporous CeO2, and the doping agent is transition metal ions. In the preparation process, transition metal nitrate and cerium nitrate are dissolved into acetone, mesoporous silica materials are added into an obtained metal nitrate acetone solution and are uniformly mixed, the mixture is naturally dried to obtain first powder, the first powder is calcined in a muffle furnace to obtain second powder, the second powder is etched by using a sodium hydroxide aqueous solution to remove the mesoporous silica materials, and the second powder is washed by using pure water and then is dried to obtain the mesoporous metal oxide catalyst for the photo-catalytic CO2 reduction, which has higher specific surface area, larger aperture and a regular pore structure. The mesoporous metal oxide catalyst is high in activity and selectivity in terms of photo-catalytic CO2 conversion, and the preparation method is relatively simple, and easy to expand.

The invention discloses a preparation method of a perovskite catalyst used for reforming methane or methanol, which comprises the following steps: the metal nitrates of A, A', B and B' are added with a complexing agent and heated to dissolute; ammonia regulation solution with pH=5-7 is added; gel is formed after dehydrating in a constant temperature water bath at the temperature of sixty to ninety DEG C; catalyst powders are obtained after the gel is dried and roasted; the general formula of the catalyst composition is A1-xA'XB1-yB'yO3, wherein x is more than or equal to 0 and less than or equal to1,y is more than or equal to 0 and less than or equal to 1, A or A' is La, Ce, Pr, Gd or Sm; B or B' is Cr, Zr, Zn, Ni, Co, Mn, Fe, Ru, Rh, Pt or Pd. The technique of the invention is simple; the cost is low; the catalyst has the high activity and the high stability; the sulfur tolerance is good; the conversion is high; the service life is long; at the same time, the invention has the advantages of being aseismatic, the small resistance and being easy to be replaced, etc. after being coated on a honeycomb structure and is suitable for mass production. The invention belongs to the field of the catalyst reforming the methane or methanol.

The invention relates to the solid fuel battery technology area, specifically relates to a composit cathode of solid oxide compound fuel cell with high stable and its preparation method. The composit cathode includes the negative pole material thin film which is composed by nanometer level spheroidal particle whose diameter is the 50-100nm the and the electrolyte basis, electrolyte basis thickness is 0.7-1mm, the negative pole material thin film quality/( the quality of negative pole material thin film + the quality of porous electrolyte skeleton) =50%-55%. The preparation method is that first prepares electrolyte powder body by the metal nitrate forerunner body, and forms the basis and the pulp, prints the pulp on the basis drtying, heating to obtain the porous three dimensional electrolyte skeleton, soaks the negative pole material forerunner body solution to the skeleton, puts heat treatment 2-3 hours under the 700-900deg.C , soaks the heat treatment cycle operation many times. The composit cathode has the very good electrochemistry performance.

The invention provides a nano spinel type catalyst and a preparation method thereof, and belongs to the field of volatile organic pollutant treatment and environment protection. By the preparation method, catalytic combustion activity of the nano spinel type catalyst can be improved effectively. The technical scheme includes that a sol precursor solution is obtained by a metal nitrate mixed solution, and xerogel is further obtained; the key point is to ignite the surface of the xerogel, a large quantity of gases are released through self-propagating combustion, fluffy tree-shaped powder is formed through combustion, and the nano spinel type catalyst is obtained finally. The nano spinel type catalyst can be applied to catalytic combustion of volatile organic pollutant gases.

The present invention belongs to the field of magnetic material preparing technology. The technological scheme is that the preparation of doped magnetic ferrite material includes mixing metal nitrate solution and citric acid solution under acid condition, adding nitrate solution of the metal to be doped, regulating PH value to produce liquid phase reaction to produce one kind of wet gel solution; evaporating excessive water via heating on electric furnace to form gel; pre-baking the gel solution at certain temperature to obtain doped nano crystalline ferrite powder; pressing the ferrite powder into required shape and sintering to obtain the doped magnetic ferrite material. The doping process is completed in the stoichiometric sol stage and this makies the prepared material homogeneous. The said preparation process is short in preparation period, low in power consumption, well controllable, high in repeatability and good in transplantation performance.