162 results about "Nitrogen doped" patented technology

The invention discloses a monatomic catalyst with an oxygen-nitrogen co-doped hollow carbon nanocage as a support carrier and a preparation method and application thereof. The monatomic catalyst comprises an oxygen-nitrogen co-doped hollow carbon nanocage carrier and a transition metal monatomic loaded on the carrier, the transition metal single atom is coordinated in the form of M (N-C) 2 (N-O) 2. Transition metal hydrochloride, 1, 10-phenanthroline monohydrate and silicon dioxide and resorcinol formaldehyde copolymer nanospheres with a core-shell structure are mixed and then subjected to a reflux reaction, rotary evaporation and drying are carried out, and an obtained solid is subjected to grinding, pyrolysis and etching to remove SiO2 to prepare the composite material. The monatomic catalyst is high in environmental interference resistance, wide in pH application range, high in activity and good in repeatability, and efficient removal of various toxic substances is achieved; the metal dissolution rate is low, and secondary pollution cannot be caused; the preparation process is simple, conditions are mild, and the method has wide industrial application prospects.

The invention discloses a high-entropy alloy / nitrogen-doped carbon nano catalytic material and a preparation method and application thereof.The nano catalytic material comprises a high-entropy alloy composed of five non-noble metals including Fe, Co, Ni, Cu and Mn and nitrogen-doped carbon synthesized with the assistance of MOF, the non-noble metal high-entropy alloy serves as a main body material, the nitrogen-doped carbon serves as a carrier material, and the nitrogen-doped carbon serves as a carrier material. A non-noble metal high-entropy alloy is loaded on nitrogen-doped carbon to construct a novel nano catalytic material, and the novel nano catalytic material is used for activating peroxydisulfate to remove antibiotics in a water body. The catalyst has the advantages of excellent chemical stability, good reusability and the like and is a novel nano catalytic material with efficient catalytic performance and environment-friendly characteristics, and the preparation method has the advantages of being simple in operation process, green, environmentally friendly, economical, feasible and the like and can be used for large-scale preparation.

A piezocatalyst containing a nitrogen doped carbon skeleton derived from a zeolitic imidazolate framework (ZIF), and a single-atom alkaline earth metal anchored on the nitrogen doped carbon skeleton, where the alkaline earth metal is selected from the group of beryllium (Be), magnesium (Mg), calcium (Ca), Strontium (Sr), and barium (Ba); the piezocatalyst includes an active cite formed with the single-atom alkaline earth metal and nitrogen atoms from the ZIF. A piezocatalytic material includes the piezocatalyst. Also provided herein is a method of manufacturing such a piezocatalyst / piezocatalytic material and an environmental remediation method employing such a piezocatalyst / piezocatalytic material.

The invention discloses a high-specific-surface-area high-nitrogen-oxygen-doped lignin porous carbon material as well as a preparation method and application thereof. The method comprises the following steps: firstly, preparing a supramolecular compound from lignin, magnesium hydroxide, cyanuric acid and melamine through solvothermal reaction, then directly carbonizing to obtain a nitrogen-doped lignin carbon / magnesium oxide compound, and activating the nitrogen-doped lignin carbon / magnesium oxide compound by using weakly corrosive sylvite to increase a micro-mesoporous structure. Therefore, the nitrogen and oxygen doped lignin porous carbon material with ultrahigh specific surface area and rich micro-mesopores is prepared. According to the obtained lignin porous carbon material with the high specific surface area and high nitrogen and oxygen doping, a large number of active sites can be provided due to the high specific surface area, wettability of the carbon material can be improved due to high nitrogen and oxygen doping, the utilization rate of the active sites is increased, and the problem that the pore diameter of the carbon material is not matched with a current carrier is solved due to the rich micro-mesoporous structure; and the specific capacitance of the zinc ion hybrid capacitor is obviously improved.

The invention belongs to the technical field of battery materials, and discloses a nitrogen-doped asphalt-based hard carbon material as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out oxidation treatment on asphalt to obtain oxidized asphalt; carrying out nitrogen doping treatment on the oxidized asphalt to obtain an asphalt hard carbon precursor; carrying out pre-carbonization and carbonization treatment on the asphalt hard carbon precursor to prepare an asphalt-based hard carbon material; a nitrogen-containing compound is used in the nitrogen doping treatment process, and the nitrogen-containing compound comprises pyridyl and / or pyrrolyl, and hydroxyl and / or aldehyde group. According to the preparation method disclosed by the invention, the asphalt is subjected to oxidation treatment, so that the asphalt contains rich oxygen-containing groups (such as hydroxyl and aldehyde group), and pyridine nitrogen (or pyrrole nitrogen) is introduced into the oxidized asphalt through aldol reaction in the nitrogen doping treatment process, so that the capacity and rate capability of the asphalt-based hard carbon material are improved.

To provide a method for growing a silicon crystal without substantially including defects.SOLUTION: A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. A melt depth and heat conditions are fixed during growth since a silicon melt is continuously replenished as the silicon melt is consumed; a crucible position is fixed; a critical v / G is determined by a hot zone structure; the continuous replenishment of silicon to the melt during the growth can grow an ingot at a fixed pulling speed coincident with the critical v / G while growing the substantial part of an ingot main body; and the continuous replenishment of silicon is achieved by periodical or continuous nitrogen addition generating a nitrogen doped ingot.SELECTED DRAWING: Figure 5

The invention discloses a preparation method and application of a high-nitrogen-doped ordered mesoporous carbon supported copper catalyst, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: by taking cane sugar and a copper-nitrogen complex as raw materials, SBA-15 as a template agent and sulfuric acid as a catalyst, carrying out equivalent-volume impregnation, low-temperature heat treatment, 800-900 DEG C high-temperature carbonization and nitric acid / hydrofluoric acid demolding to prepare pyrrole nitrogen enriched or pyridine nitrogen enriched high-nitrogen doped ordered mesoporous carbon with a large specific surface area; the preparation method comprises the following steps: loading a copper species on high-nitrogen-doped ordered mesoporous carbon by adopting an equivalent-volume impregnation method, and reducing at 350-400 DEG C to prepare the high-nitrogen-doped ordered mesoporous carbon loaded copper catalyst. The prepared catalyst is high in nitrogen content, large in specific surface area, high in pyridine nitrogen or pyrrole nitrogen enrichment degree and uniform in copper particle dispersion and shows efficient catalytic performance in methanol oxidative carbonylation reaction, and the highest methanol conversion rate is 9.3%.

The invention discloses a nitrogen-doped carbon dot material with a high emulsification level and a preparation method thereof, and belongs to the technical field of two-dimensional interface materials. The method comprises the following steps: firstly, adding a NaOH aqueous solution into an acetaldehyde aqueous solution, then adding hydrochloric acid to adjust the pH value of the solution to be neutral, stirring for reaction, then centrifuging to retain precipitate, extracting with liquid nitrogen, and freeze-drying to obtain a carbon dot material; and adding the carbon dot material into a system of potassium methoxide and a nitrogen source, carrying out heating reaction, carrying out centrifugation, retaining the precipitate, drying, and preparing the nitrogen-doped carbon dot material with a high emulsification level by controlling the reaction time, regulating the acid amount and changing the nitrogen source. A large amount of nanoscale nitrogen-doped carbon dot material emulsifiers with an amphiphilic emulsification effect can be rapidly synthesized under mild reaction conditions, the obtained nitrogen-doped carbon dot material is uniform in size and high in dispersity, the emulsification requirements under different oil phase conditions can be met, the preparation process is simple, dialysis and centrifugation are not needed in industrial production, and the method is suitable for industrial production. And the nitrogen-doped carbon dot material with a high emulsification level can be prepared only through centrifugation and drying.

The invention provides a preparation method of a gate oxide layer and a gate, and the method comprises the steps: carrying out the rapid thermal annealing treatment of a silicon-based substrate in a nitrogen-containing gas atmosphere, which belongs to a non-destructive nitrogen doping mode, and carrying out the nitrogen pre-doping on the surface of the silicon-based substrate, so as to reduce the doping amount needed by the subsequent plasma nitrogen doping; therefore, the damage of the plasma nitrogen doping process to the SiON gate oxide layer is reduced, and the interface defect between the SiON gate oxide layer and the silicon-based substrate interface is reduced. Besides, after the nitrogen pre-doped layer is formed, the thermal oxidation process is carried out on the silicon-based substrate to form the silicon dioxide gate oxide layer, so that the damage to the SiON gate oxide layer film is reduced, and the interface defect between the SiON gate oxide layer and the silicon-based substrate interface is further reduced; moreover, the laser rapid annealing treatment can remove the intrinsic oxide layer on the surface of the SiON gate oxide layer, repair the damage to the crystal lattice of the SiON gate oxide layer caused by the plasma nitrogen doping treatment process, improve the film quality and repair the interface.

Semiconductor devices including a nitrogen doped field relief dielectric layer are described. The microelectronic device comprises a substrate including a body region having a first conductivity type and a drain drift region having a second conductivity type opposite the first conductivity type; a gate dielectric layer on the substrate, the gate dielectric layer extending over the body region and the drift region and a doped field relief dielectric layer on the drift region. Doping of the field relief dielectric layer with nitrogen raises the dielectric constant of the field relief dielectric above that of pure silicon dioxide. Increasing the dielectric constant of the field relief dielectric layer may improve channel hot carrier performance, improve breakdown voltage, and reduce the specific on resistance of the microelectronic device compared to a microelectronic device of similar size with a field relief dielectric which is not doped with nitrogen.

The invention provides micron-sized diamond particles with NV color centers and a preparation method and application of the micron-sized diamond particles with the NV color centers. The preparation method comprises the following steps that cleaned diamond seed crystals are placed in a microwave chemical vapor deposition chamber, CH4, H2 and N2 are introduced, and nitrogen-doped monocrystal diamond grows; the nitrogen-doped single crystal diamond is sequentially subjected to electron irradiation and vacuum annealing treatment, and the single crystal diamond with the NV color center is obtained; and the single crystal diamond with the NV color center is polished, cut and annealed, and the micron-sized diamond particles with the NV color center are obtained. The prepared micron-sized diamond particles are high in NV color center concentration and can be used for preparing a magnetic detection probe.

The invention belongs to the technical field of carbon materials and new energy materials, and particularly relates to a modified resin-based nitrogen-containing hard carbon material as well as a preparation method and application thereof. Melamine is introduced into a phenolic resin system to synthesize phenol-melamine-formaldehyde resin, triazacyclo-covalently polymerized resin molecules are formed, an organic pore-forming agent is synchronously used for adjusting the pore channel structure of the material, and after high-temperature carbonization, the high-temperature carbonization is performed to obtain the high-temperature-resistant phenolic resin. And the hard carbon negative electrode material for the sodium ion battery, which is high in nitrogen doping, rich in closed pore structure and disordered in microstructure, is prepared. After melamine participates in the reaction, a triazacyclo ring with a stable structure is introduced into a resin molecular structure, and the nitrogen-doped hard carbon material is formed after carbonization. Nitrogen elements are uniformly distributed in the carbon material and on the surface of the carbon material, abundant active sites are provided, and the reversible capacity of sodium ion storage can be improved.

The invention relates to a nitrogen-doped carbon shell coated nanoparticle structure catalyst based on beta-cyclodextrin and application of the catalyst in a zinc-air battery, beta-cyclodextrin, urea and cobalt nitrate hexahydrate are directly mixed, beta-cyclodextrin is complexed on the periphery of cobalt through complexation, meanwhile, urea is used as a nitrogen source, and the nitrogen-doped carbon shell coated nanoparticle structure catalyst based on beta-cyclodextrin is prepared. Nitrogen atoms are introduced into beta-cyclodextrin, the morphology of beta-cyclodextrin complexed on the periphery of cobalt is kept after drying, urea is decomposed into a nitrogen source through high-temperature heat treatment, beta-cyclodextrin is partially carbonized to form a conductive carbon matrix, the nitrogen atoms are doped into the carbon matrix, and a nitrogen-doped carbon shell structure with high conductivity is formed. The nitrogen-doped beta-cyclodextrin coated cobalt nanoparticle catalyst with the core-shell structure is obtained, carbonized beta-cyclodextrin provides a conductive network, the electron transfer efficiency is improved, the electron structure of a carbon material is changed by nitrogen doping, the conductivity and the oxidation reduction activity are improved, meanwhile, the introduction of nitrogen atoms is beneficial to increase of the number of active sites, and the nitrogen-doped beta-cyclodextrin coated cobalt nanoparticle catalyst with the core-shell structure is prepared. Therefore, the catalytic activity of the ORR is improved.

The present invention discloses a biphasic Nitrogen doped sodiophilic anode. The present disclosure also provides a process of preparing a defect rich Nitrogen doped waste polymer derived carbon (PDC) and commercial polyvinyl based polymer derived carbon (PRC) as carbon precursor for use in sodium ion / metal battery with high capacity, long cyclic stability in both half cell and full cell.

The invention relates to the technical field of acid tail gas treatment, and discloses a boron-nitrogen-doped aluminum oxide catalyst as well as a preparation method and application thereof. The method comprises the following steps: (1) mixing an aluminum source, a nitrogen source, a boron source and water to obtain a mixed solution, then adding a peptizing agent to adjust the pH of the mixed solution to be acidic, and then standing and aging; (2) drying the material subjected to standing and aging in the step (1), then roasting under protective gas, and then sequentially carrying out high-temperature nitriding and cooling; and (3) carrying out plasma treatment on the material cooled in the step (2). The catalyst prepared by the method has large specific surface area and catalytic activity, can well capture water and carbonyl sulfide, converts carbonyl sulfide into hydrogen sulfide and improves the purity and yield of enriched hydrogen sulfide, and the preparation method of the catalyst is simple and efficient.

The invention discloses a method for preparing 4-propyl syringol by catalyzing hydrogenolysis of lignin through cobalt-nitrogen co-doped porous carbon. According to the method, organic soluble lignin is taken as a raw material, lignin-based cobalt-nitrogen co-doped porous carbon is taken as a catalyst, small molecular alcohol is taken as a reaction medium, stirring reaction is performed under the hydrogen pressure of 1-2MPa and at the temperature of 190-260 DEG C, and the organic soluble lignin is selectively hydrogenolyzed into a monophenol chemical mainly containing 4-propyl syringol; the catalyst disclosed by the invention does not need to be subjected to carrier preparation, impregnation and reduction, and also does not need to be subjected to mofs material preparation and roasting, so that the catalyst has obvious advantages in a catalyst preparation process; according to the catalyst, transition metal is used as catalytic active metal, and the metal is uniformly dispersed on the surface of the catalyst in a monatomic-level dispersion degree to form a complex with CoN4 as a main component with carbon and nitrogen; the catalyst is wide in raw material source, low in metal content and obvious in cost advantage, and has the advantage of large-scale production.

The invention relates to the technical field of semiconductors, in particular to an epitaxial structure and a preparation method thereof.The epitaxial structure comprises a substrate, a combined buffer layer comprising at least one buffer unit and a drift layer which are sequentially stacked from bottom to top; wherein each buffer unit comprises a nitrogen-doped buffer unit and a phosphorus-doped buffer unit. According to the epitaxial structure provided by the invention, by performing nitrogen and phosphorus doping on the surface of the substrate to form epitaxy of the composite structure buffer layer, the induction probability of stacking fault in the initial epitaxy stage can be reduced, and meanwhile, a large amount of atomic phosphorus is doped in the epitaxy process, and the lattice constant can be expanded, so that the problem that the nitrogen-doped lattice constant is reduced in the mass production process is solved, and the yield of the product is improved. Therefore, the wafer warping is improved, and the yield is improved.

The invention relates to the technical field of lithium ion batteries, in particular to nitrogen-doped lithium iron phosphate as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out ball milling on iron phosphate, lithium carbonate, starch and a nitrogen-containing compound in water, and uniformly mixing to form lithium iron phosphate precursor slurry; then carrying out spray drying on the obtained precursor slurry to obtain lithium iron phosphate precursor powder; and finally, calcining the obtained lithium iron phosphate precursor powder in an inert atmosphere to obtain the nitrogen-doped lithium iron phosphate powder. The prepared lithium iron phosphate powder has a very uniform carbon coating layer, compared with traditional lithium iron phosphate and direct carbon-coated lithium iron phosphate, the lithium iron phosphate powder has high conductivity, and a lithium ion battery has excellent charge-discharge performance under large current.

The invention belongs to the technical field of phenol hydrogenation catalysis, and discloses a nitrogen-doped porous carbon sphere loaded palladium-based catalyst as well as a preparation method and application thereof in order to solve the problems that active components of an existing catalyst are difficult to highly disperse, the reaction condition is harsh and the stability is poor. The nitrogen-doped porous carbon spheres derived from the nitrogen-doped polymer are used as carriers to load Pd, and high dispersion of Pd is promoted by N sites on the nitrogen-doped porous carbon spheres, so that the number of active centers is increased, and cyclohexanone can be prepared through phenol hydrogenation under mild conditions; and the interaction between the N site and the Pd metal hinders the loss of the active component, so that the high stability of the catalyst is realized. In addition, N sites on the nitrogen-doped porous carbon spheres can promote vertical adsorption of phenol molecules, so that high-selectivity preparation of cyclohexanone is realized.

The invention discloses high-nitrogen-doped layered porous waxberry kernel-based activated carbon and a preparation method and application thereof.The preparation method of the activated carbon comprises the steps that waxberry kernels are washed with water, dried, crushed into particles, screened, soaked in a nitric acid solution for pretreatment, washed and dried to obtain a pre-oxidized precursor, then the pre-oxidized precursor is mixed with a nitrogen source and a potassium activating agent, and the high-nitrogen-doped layered porous waxberry kernel-based activated carbon is obtained. The preparation method comprises the following steps: firstly, preparing a one-step impregnated nitrogen-doped carbon precursor, heating, stirring and drying in deionized water to obtain the one-step impregnated nitrogen-doped carbon precursor, then calcining and activating in a mixed atmosphere of nitrogen and ammonia gas, finally soaking in a hydrochloric acid solution, washing, filtering, drying and screening to obtain the final finished product nitrogen-doped layered porous activated carbon. According to the activated carbon, the waxberry kernels serve as raw materials, urea and ammonia gas serve as nitrogen sources, KHCO3 serves as an activating agent, the activated carbon is heated, stirred and reacted in water and then calcined and activated, high-temperature activation and synergistic nitrogen doping are achieved, and compared with a traditional nitrogen doping mode, the activated carbon is higher in nitrogen doping rate, richer in specific surface area and pore structure and obvious in performance advantage.

The present invention discloses a core-shell Ni / Co alloy @ nitrogen-doped carbon-based absorbing composite material and a preparation method thereof. First, a Ni / Co-MOF precursor is prepared by a simple hydrothermal reaction, and then a core-shell Ni / Co@C composite absorbing material is obtained by high-temperature treatment under an argon inert environment. The composite absorbing material has an optimal effective absorbing bandwidth (RL) value of 8.9 GHz at a thickness of 3.5 mm, and can reach 71.9 dB at a frequency of 8.9 GHz. The effective absorbing bandwidth of RL<10 is as high as 16 GHz, covering the S, C, X and Ku bands, and due to the formation of a carbon-wrapped nickel-cobalt core-shell structure, the material has good stability. The absorbing material prepared by the method of the present invention is environmentally friendly, has good stability, has a wide absorbing bandwidth, has high reflection loss, is simple in process, and is suitable for large-scale production.

The invention discloses a method for enriching palladium from palladium-containing waste liquid by using chelate resin and preparing a nitrogen-doped graphitized carbon-loaded nano-palladium catalyst and application. The problems of loss of metal palladium, environmental pollution and the like in a palladium catalyst recovery and reutilization process are solved. The method for preparing the nitrogen-doped graphitized carbon-loaded nano-palladium catalyst comprises the following steps: 1, adding chelating resin into an aqueous solution containing PdCl4 < 2->, stirring and adsorbing, centrifuging, and drying to obtain PdCl4 < 2->-loaded chelating resin; and 2, putting the chelate resin loaded with the PdCl4 < 2-> into a tubular furnace, and carrying out a carbon thermal reduction reaction at the temperature of 500-1000 DEG C in a nitrogen atmosphere. According to the preparation method of the nitrogen-doped graphitized carbon loaded nano-palladium catalyst, nitrogen-doped graphitized carbon is formed under the action of metal ions, so that the conductivity and the electron transmission capability of a carrier are enhanced, and the activity and the stability of a Pd / NGC catalyst in a 12H-NEC dehydrogenation reaction process are improved.

The present application relates to a kind of for metallurgical coal gas to remove organic sulfur nitrogen-doped catalyst and its preparation method and application, including the following steps: with soluble aluminum salt as carrier, it is prepared with certain proportion of nitrogen source compound mixed solution, then precipitate completely in alkaline environment, after stirring, aging, drying treatment, with high temperature calcination nitrogen-doped Al2O3 catalyst is obtained.The catalyst has more nitrogen site, stronger nitrogen doping capacity, so that the basic center of catalyst increases, improves the catalytic activity when catalytic elimination carbonyl sulfur, while reducing the adsorption of H2S, improves H2S yield, reduces the formation of sulfur, ensures the activity and stability of catalyst, prolongs the life of catalyst.

The present invention relates to the technical field of nanopowder preparation, and discloses a method for preparing a nitrogen-doped biochar-loaded iron nitride composite material. The process is as follows: (1) potassium ferrate, urea, and waste tea powder are ground and mixed in proportion to obtain a first mixture; (2) the first mixture is reacted in a temperature range of 50-70°C to obtain a second mixture; (3) the second mixture is reacted in a temperature range of 600-800°C for 1-3 hours, and then cooled to room temperature to obtain a third mixture; (4) the third mixture is washed and dried to obtain a nitrogen-doped biochar-loaded iron nitride composite material. Compared with the existing preparation process, the beneficial effect of the present invention is that the operation steps only include grinding, stirring, heating, etc., the operation is simpler, the overall process only involves one pyrolysis, the energy consumption is lower, and the toxic gas ammonia is not used, and the operation is safer. The material can degrade trichloroethylene without an anaerobic environment and can be used for the remediation of organochlorine-contaminated groundwater environment.

This invention discloses a two-step method for preparing nitrogen-doped three-dimensional network phenolic resin-based composite carbon materials and their applications. The method uses an alkaline environment provided by ammonia to induce addition condensation polymerization of phenol and formaldehyde to obtain a preliminary nitrogen-doped phenolic resin. This resin is then mixed with melamine resin to achieve a second step of nitrogen introduction, and after being composited with sodium alginate, it is cross-linked with CaCl2 to obtain a three-dimensional hydrogel precursor. After carbonization and activation treatment, a nitrogen-doped porous carbon material is obtained. This material possesses both micro- and mesoporous synergy and multiple types of nitrogen functional sites, exhibiting high specific surface area capacitance and excellent cycling stability in supercapacitors. Compared with existing schemes that only use NaOH without introducing dual-source nitrogen doping (such as CN119724955A), this invention achieves synergistic optimization of structure, chemical sites, and transport through ammonia pre-doping, secondary nitrogen doping with melamine resin, and a ternary interpenetrating network. The process is simple, uses inexpensive raw materials, and is suitable for large-scale production.

The present invention belongs to the technical field of anode-free sodium metal batteries, and specifically discloses a modified current collector for anode-free sodium batteries, a preparation method thereof, and an application thereof. The preparation method of the present invention is as follows: on the basis of preparing polypyrrole, by adding a transition metal salt, the nitrogen doping type in polypyrrole-derived nitrogen-doped nanocarbon particles is regulated. The modified current collector for anode-free sodium batteries prepared by the present invention has a high relative content of N-6 and N-5 type doped nitrogen, thereby improving the sodium affinity of the nitrogen-doped coating, reducing the nucleation point of sodium metal, and improving the reversibility of the sodium deposition / stripping reaction, thereby improving the electrochemical performance of the cathode-free sodium battery.

The invention discloses a preparation method and application of a cobalt-nitrogen-doped mesoporous carbon catalyst, and belongs to the technical field of catalyst preparation, and the preparation method comprises the following steps: mixing and grinding glucose and an SBA-15 mesoporous molecular sieve, pyrolyzing in a nitrogen atmosphere, soaking the obtained product in hydrofluoric acid to remove an SBA-15 template, alternately centrifuging with water and ethanol to obtain a precipitate, and drying to obtain the cobalt-nitrogen-doped mesoporous carbon catalyst. Mesoporous carbon is obtained; the preparation method comprises the following steps: respectively dissolving phenanthroline and cobalt chloride hexahydrate in ethanol, and mixing to form a Co-phen solution; and soaking the obtained mesoporous carbon in a Co-phen solution, evaporating the solvent after soaking, grinding into powder, and carrying out heat treatment in a nitrogen atmosphere to obtain the cobalt-nitrogen doped mesoporous carbon catalyst. The cobalt-nitrogen-doped mesoporous carbon catalyst shows excellent oxygen reduction catalytic activity under the alkaline condition, the half-wave potential reaches 0.873 V and is close to a 4-electron transfer path, and the stability and methanol tolerance are superior to those of a commercial Pt / C catalyst.

The present application relates to the technical field of carbon nanotubes and provides nitrogen-doped carbon nanotubes and a preparation method thereof, wherein the preparation method of the nitrogen-doped carbon nanotubes comprises the following steps: providing a lamellar catalyst with a metal carrier; reducing and activating the lamellar catalyst to obtain an activated catalyst; introducing an atmosphere of a carbon source and a nitrogen source into the activated catalyst to react and obtain nitrogen-doped carbon nanotubes. The preparation method of the present application provides a lamellar catalyst with a metal carrier, wherein the catalytically active component (metal) of the lamellar catalyst has a strong adsorption capacity on the carrier and an ion exchange capacity with the carrier, making it easier for the catalytically active component elements to enter the mesopores and micropores on the inner surface of the lamellar carrier material, better utilizing the surface area of ​​the carrier, achieving uniform dispersion of the catalytically active elements, and improving the loading amount and uniformity of the lamellar catalyst with the metal carrier; the preparation method is suitable for fluidized bed production processes and can be used for industrial production.

The invention belongs to the field of environmental protection and air purification, and particularly relates to a nitrogen-doped titanium dioxide loaded copper nanoparticle photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: synthesizing an N-TiO2 carrier through a low-temperature hydrolysis method, and loading Cu NPs on the N-TiO2 carrier through a wet impregnation method to prepare the Cu / N-TiO2 catalyst. The Cu / N-TiO2 photocatalyst obtained by the invention can effectively catalyze and remove NO and CO under the conditions of 120-210 DEG C and visible light, and has good stability and NH3 selectivity. Compared with an N-TiO2 carrier, the performance of removing NO and CO through photocatalysis and the NH3 selectivity are obviously improved. The high-cost limitation of a traditional noble metal catalyst is broken through, an innovative solution is provided for low-temperature photo-thermal synergistic purification of motor vehicle exhaust, and application and popularization are facilitated.

Nitrogen doping an insulating layer can lower the bandgap of a magnetic storage device. It is challenging to nitrogen dope magnesium oxide (MgO). A cation can be added to allow the magnesium to hold onto the nitrogen dopant without highly oxidizing or nitriding the cation. The resulting nitrogen doped MgXO, where X is the cation, has a lower bandgap compared to a much similar barrier layer that has neither nitrogen nor a cation thus improving thermal and electrical reliabilities. The nitrogen doped MgXO is non-stoichiometric whereas comparably, an oxynitride is stoichiometric. Example cations that may be used include aluminum, titanium, vanadium, chromium, and scandium.