74 results about "Nitrogen doping" patented technology

The application discloses a preparation method of nitrogen-doped carbon-silicon nanofibers and application of the nitrogen-doped carbon-silicon nanofibers in a lithium ion battery negative electrode material, and belongs to the technical field of lithium ion battery negative electrode materials. The method comprises the following steps: mixing silicon nanoparticles and a carbon source, performing electrostatic spinning, stabilization treatment and carbonization treatment, and obtaining carbon-silicon nanofibers; and then mixing the carbon-silicon nanofibers with a nitrogen source, performing heat treatment under an inert atmosphere, making nitrogen elements doped into a carbon skeleton, and obtaining nitrogen-doped carbon-silicon nanofibers. The material obtained by the application is a one-dimensional nanofiber structure, silicon particles are uniformly wrapped in carbon fibers, and nitrogen elements are uniformly distributed in the carbon skeleton. The method can realize uniform nitrogen doping while maintaining the microstructure of the material, and significantly improves the electronic conductivity and interface stability of the material. The material obtained by the application is used as a lithium ion battery negative electrode, and exhibits high reversible capacity and excellent cycle stability.

This invention relates to a nitrogen-doped hard carbon material and its preparation method, belonging to the field of sodium-ion battery technology. The preparation method of this invention includes the following steps: S1, urea and a glycosyl carbon source are thoroughly mixed and heated to melt, then cooled to obtain a eutectic salt; S2, under a protective atmosphere, the eutectic salt is prepolymerized, pyrolyzed, and carbonized to obtain the nitrogen-doped hard carbon material. First, urea and a glycosyl carbon source form a eutectic salt. During this process, the strongly polar functional groups in the glycosyl carbon source form a hydrogen bond network with the amino and carbonyl groups in the urea. This hydrogen bond network can restrict the free movement of urea molecules and constrain their thermal decomposition path, thereby delaying and inhibiting premature decomposition of urea, while simultaneously improving the nitrogen retention rate. A three-stage heating program is used to achieve layered nitrogen doping. This segmented temperature control strategy constructs a layered doping mechanism of "first building a carbon framework, then introducing nitrogen atoms, and finally stabilizing the carbon framework structure."

The present application relates to the field of battery, especially to a gradient pore hierarchical nitrogen-doped carbon-coated composite sodium supplement agent and its preparation method and application, comprising: a composite sodium supplement agent core and a coating layer coated on the surface of the composite sodium supplement agent core; wherein the composite sodium supplement agent core comprises: an inorganic sodium supplement phase and an organic sodium supplement phase; the coating layer comprises from inside to outside: an inner dense amorphous carbon layer, a middle mesoporous carbon layer and an outer macroporous carbon layer. The present application innovatively designs a gradient pore carbon coating structure from inside to outside, the inner dense amorphous carbon layer realizes efficient isolation protection, the middle mesoporous carbon layer solves the problem of ion transmission obstruction, and the outer macroporous carbon layer improves the electronic conduction and volume buffering capacity, completely solving the inherent contradiction between the denseness of the traditional carbon coating layer and ion transmission, realizing the synergy and unity of "isolation protection-ion transmission-electronic conduction".

A CMOS image sensor and a forming method thereof, the method comprising: providing a semiconductor substrate; forming a plurality of N-type source-drain regions in the semiconductor substrate; wherein forming the plurality of N-type source-drain regions in the semiconductor substrate comprises: forming a plurality of arsenic-doped regions in the semiconductor substrate; wherein before forming the plurality of arsenic-doped regions in the semiconductor substrate, further comprising: forming a plurality of nitrogen-doped regions in the semiconductor substrate, the nitrogen-doped regions corresponding one-to-one to the arsenic-doped regions, and the corresponding nitrogen-doped region and arsenic-doped region having an overlapping region. The present application can effectively improve the device quality of the CMOS image sensor without changing the existing heavy-atom arsenic-doping process.

The embodiments of this disclosure generally relate to the fabrication of integrated circuits. More specifically, the embodiments described herein provide techniques for depositing nitrogen-doped diamond-like carbon films for patterning applications. In one or more embodiments, a method for processing a substrate includes: flowing a deposition gas containing a hydrocarbon compound and a nitrogen dopant compound into a processing volume of a process chamber on which the substrate is positioned on an electrostatic chuck; and generating plasma at or above the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a nitrogen-doped diamond-like carbon film on the substrate. The nitrogen-doped diamond-like carbon film has a density greater than 1.5 g / cc and a compressive stress of about -20 MPa to less than -600 MPa.

The embodiment of the application provides a kind of composite positive material and its preparation method, lithium-sulfur battery positive sheet and lithium-sulfur battery.The composite positive material includes porous carbon matrix, metal atom and carbon nanotube, carbon nanotube is in situ grown on the metal atom attached to the pore and surface of porous carbon matrix, and N element is introduced in the growth process of carbon nanotube.The application is in situ grown by carbon nanotube on porous carbon skeleton and then adjusts the pore structure of porous composite material, effectively inhibits the shuttle effect of polysulfide.At the same time, nitrogen doping helps to increase the chemical adsorption capacity of polysulfide, and also effectively inhibits the shuttle effect of polysulfide, thereby improving the utilization rate of sulfur and the cycle life of battery.The preparation method of nanotube composite material for inhibiting the shuttle effect of lithium polysulfide in the prior art is complex and has high cost.

This invention discloses a single-crystal diamond and its preparation method, relating to the field of inorganic materials. In preparing the single-crystal diamond, a seed crystal with a (100) crystal plane is selected, polished, and then etched to obtain a pretreated seed crystal. A single-crystal diamond base layer is grown on the surface of the pretreated seed crystal to obtain a diamond with a base layer. The diamond with the base layer is cut, grown in a nitrogen-containing environment, annealed, and finally coated with silicon to obtain the single-crystal diamond. The single-crystal diamond obtained by this invention can provide a clean and regular "starting point" for growth by pre-removing the edge regions with poor initial growth quality, fundamentally avoiding the problem of polycrystalline diamonds starting from the original edge and rapidly enveloping the surface, thereby effectively suppressing edge parasitic deposition. Simultaneously, nitrogen doping and finally silicon coating on the surface result in superior electrical properties.

To improve the responsiveness of the resistance value to humidity fluctuations. [Solution] The method for manufacturing a moisture-sensitive material S110 includes: a first step S110-1 in which a first laminate is manufactured by forming a first layer made of graphite on a substrate; a second step S110-2 in which a second laminate is manufactured by forming a second layer made of a plurality of nitrogen-doped carbon nanowalls on the first layer of the first laminate; a third step S110-3 in which a third laminate is manufactured by attaching one or more catalyst particles to the plurality of carbon nanowalls constituting the second layer of the second laminate; and a fourth step S110-4 in which the third laminate is subjected to hydrogen treatment.

The present application relates to the technical field of stabilizer in oilfield operation, in particular to a kind of fiber structure stabilizer for fracturing and a preparation method thereof, nitrogen-doped modified graphene oxide in the present application is realized nitrogen atom doping by the compounding of chitosan and graphene oxide and high-temperature heat treatment, both the high specific surface area and mechanical strength characteristics of graphene are retained, and active sites are introduced by nitrogen doping, the adsorption and combination capacity with fiber network is enhanced, three-dimensional support skeleton is formed in fracturing fluid, effectively resist formation pressure impact, prevent fiber structure collapse;Secondly, crosslinking modified cellulose forms network structure by epoxy chloropropane crosslinking, which can significantly improve the temperature resistance and salt tolerance of cellulose, the modified cellulose molecular chain not only maintains the dispersion characteristics of hydrophilic carboxyl group, but also introduces hydrophobic interaction through tertiary amine group, forming a double stabilizing mechanism of hydration layer and hydrophobic microzone in fracturing fluid, enhancing the shear resistance of fiber bundle.

The application relates to the technical field of carbon material preparation, and discloses a nitrogen-doped spherical mesoporous carbon material dispersing metal single atoms and a preparation method thereof, which comprises the following steps: introducing a metal precursor containing a vinyl group in a prepolymer stage, and grafting a metal center on a polymer skeleton in situ through chemical bonding; then, using an amphiphilic block copolymer as a soft template, combining an emulsification solidification process to prepare a phenolic resin ball; finally, carbonizing the resin ball, and activating the resin ball by inputting water vapor with a specific proportion, so that mesopores and micropores are constructed. The application effectively inhibits the agglomeration of metal atoms at high temperatures through in-situ chemical bonding, and realizes the high-dispersion loading of single atoms; meanwhile, the synergistic effect of the soft template and water vapor activation endows the material with a high specific surface area and a developed hierarchical pore structure. When the obtained material is used as an electrode of a super capacitor, the material exhibits high specific capacitance, excellent rate performance and good cycle stability.

This invention belongs to the field of graphene materials and discloses a magnetic nitrogen-doped reduced graphene oxide, its preparation method, and its application. The method includes the following steps: (1) preparation of frangipani extract; (2) adding iron salt, sodium acetate, and frangipani extract to an aqueous solution of graphene oxide, ultrasonically mixing until homogeneous, and then carrying out a hydrothermal reaction. After the reaction is complete, the solid is separated using a strong magnet and washed, and then freeze-dried to obtain magnetic nitrogen-doped reduced graphene oxide. The prepared magnetic nitrogen-doped reduced graphene oxide material, used as a glassy carbon electrode modification material, exhibits excellent electrochemical performance and can be applied in the rapid detection of Cd(II). The synthesis method of this invention has the advantages of being simple, easy to implement, and environmentally friendly. The prepared magnetic nitrogen-doped reduced graphene oxide has important application value in sensing, catalysis, optics, and electronics.

The application discloses a multifunctional anti-corrosion blue-green algae carbon material electrode and a preparation method and application thereof, and belongs to the field of electrode materials. The application takes blue-green algae carbon material as a core. The cell structure of blue-green algae is naturally provided with a multistage pore structure, and can be converted into hierarchical porous carbon after pyrolysis, which is beneficial to in-situ nitrogen doping, has a large specific surface area, high electrochemical activity, and strong conductivity. The wettability of the carbon felt gap is improved by increasing the gap. Meanwhile, through three paths of improving anchoring capacity by KOH surface chemical modification, maintaining organic acid obtained by carbon fixation by compounding Co3O4 slurry and precisely loading active components, and constructing and cross-linking double protective layers, the uniform distribution of functional materials, the dense and firm protective layer, and the reservation of electrode conductivity are unified, and finally, a long-acting composite electrode suitable for the electrolyte environment of a carbon fixation photovoltaic flow battery is prepared.

This invention provides a silicon-carbon anode material, its preparation method, an anode, and a lithium-ion battery. The silicon-carbon anode material includes a silicon-carbon material and a passivation layer coated on the surface of the silicon-carbon material, wherein the passivation layer is nitrogen-doped silicon oxide. The silicon-carbon material includes porous carbon material, nano-silicon particles, and a silicon layer. The nano-silicon particles are dispersed in the pores of the porous carbon material, and the silicon layer coats the surface of the porous carbon material. Compared with traditional coating layers, the nitrogen-doped silicon oxide layer has better conductivity and chemical stability, which can improve the kinetic performance of the silicon-carbon anode material, thereby improving its rate performance and solving the problem of poor electronic conductivity and rate performance in existing silicon-based anode materials.

The application discloses a kind of cathode material for low-temperature metal fuel cell and its preparation method and application, preparation nitrogen-doped carbon nanotube as carrier;Utilize the liquid phase oxidation-reduction method of potassium permanganate and manganese sulfate, and introduce cobalt nitrate to carry out one-step hydrothermal synthesis;Utilize the doping effect of cobalt ion to control product crystal phase, and synthesize the rod-shaped structure of MnOOH and CoMn2O4 Nanocomposite on carrier.The obtained cathode material is through the synergistic effect of nitrogen-doped carbon carrier and metal oxide, significantly reduce the energy barrier of low-temperature oxygen reduction reaction.The cathode material has 0.79 V half-wave potential and 5.58 mA·cm ‑2 Limit diffusion current density under-10 ℃ environment;The assembled aluminum-air battery shows 1.56 V open-circuit voltage and 9.71 mW·cm ‑2 Power density under-40 ℃ environment, can be discharged stably for 16.2 h under 2 mA·cm ‑2 Current density, better than commercial Pt / C catalyst.In cold region emergency power supply, polar scientific expedition, military equipment and other extreme low-temperature scenes have significant application value.

The application relates to a positive electrode material and a preparation method and application thereof, the positive electrode material comprising a core, an inner coating layer and an outer coating layer which are sequentially coated on the surface of the core from inside to outside, the core comprising phosphate particles, the inner coating layer being a nitrogen-doped carbon layer, and the outer coating layer being a layer of a layered structure material; wherein the mass percentage of nitrogen in the nitrogen-doped carbon layer is 0.5% to 8%. According to the scheme, the positive electrode material has high conductivity, interface stability and structural integrity, the transition metal dissolution amount after high-temperature storage is low, and the conductivity of the battery can be improved, so that the battery has excellent high-temperature cycle performance and rate performance.

The present application relates to nitrogen-doped carbon nanotubes and a method for preparing and using the same and a method for preparing hydrogen peroxide. The nitrogen-doped carbon nanotubes comprise carbon nanotubes and pyridine groups grafted on the carbon nanotubes. The nitrogen-doped carbon nanotubes of the present application are modified carbon nanotubes with a clear functional structure under normal temperature and pressure and mild reaction conditions. The sp2 hybridized carbon nanotubes are modified by pyridine groups with a specific structure to generate pyridine-modified carbon nanotubes with a clear structure and electron transfer between the carbon plane and the substituent group, which can be used as electrode materials in the electrocatalytic preparation of hydrogen peroxide.

This invention belongs to the field of carbon material preparation technology, and provides a nitrogen-doped porous carbon nanosheet, its preparation method, and its application. The preparation method of this invention involves sequentially pyrolyzing, acid washing, and drying white radish to obtain the nitrogen-doped porous carbon nanosheet; the pyrolysis temperature is 500-900℃; the pyrolysis is carried out under a protective atmosphere. This invention uses white radish as a biomass raw material, and nitrogen-doped porous carbon nanosheets can be obtained through pyrolysis and acid washing. The preparation method of this invention is simple to operate and low in cost; moreover, compared with existing technologies that add nitrogen-containing organic matter such as urea for nitrogen doping, the operation is simpler and more environmentally friendly. Data from the examples show that the nitrogen-doped porous carbon nanosheets prepared by this invention have excellent capacitance performance, ultra-high specific capacitance, and good rate performance.

This invention discloses a method for preparing a nitrogen-doped reduced graphene oxide / cellulose asymmetric modified separator for lithium-sulfur batteries. The modified separator is made by coating nitrogen-doped reduced graphene oxide and cellulose onto both sides of the separator. This invention utilizes nitrogen-doped reduced graphene oxide to adsorb and catalyze the conversion of lithium polysulfides on the positive electrode side, and utilizes cellulose to uniformly deposit metallic lithium and suppress dendrite growth on the negative electrode side, while simultaneously optimizing the redox reactions at both the positive and negative electrodes. Lithium-sulfur batteries assembled based on the asymmetric modified separator of this invention exhibit excellent cycle stability, high discharge specific capacity, and good rate performance.

The application belongs to the technical field of photocatalytic materials, and particularly relates to a photocatalyst with a heterojunction of a carbon layer with adjacent Ni-Co double-site nitrogen coordination-SrTiO3, and preparation and application thereof. A nickel source, a cobalt source and a carbon precursor are mixed to form a precursor component; the precursor component is mixed with a nitrogen-containing precursor and heat-treated under an inert atmosphere to obtain a nitrogen-doped carbon material containing Ni-Co adjacent double sites; and then the nitrogen-doped carbon material is solvent-assembled with SrTiO3 to prepare a target photocatalyst. The photocatalyst comprises a SrTiO3 carrier and a nitrogen-doped carbon layer containing Ni-Co adjacent double sites loaded on the surface of the carrier, Ni and Co exist in a highly dispersed state and are coordinated with N, and a heterojunction coupling structure is formed between the nitrogen-doped carbon layer and the SrTiO3. The photocatalyst is used for overall decomposition of water, and has good photocatalytic activity and long-term stability. The application has good application prospects because raw materials are easy to obtain, the process is simple, and no noble metal is needed.

This invention discloses a conductive agent for solid-state lithium batteries and its preparation method, belonging to the field of lithium battery anode material technology. Addressing the problems of poor flexibility, easy breakage of the conductive network during silicon-carbon anode expansion, weak ion conduction, high interfacial impedance, and easy formation of lithium dendrites in existing conductive agents, this invention's conductive agent features an NCF@LFIC core-shell structure: a 100-300nm flexible NCF core is layered to form a high-toughness three-dimensional conductive network; an outer 5-20nm fast ion conductor shell is grown in situ, constructing an electron-ion dual continuous channel; the LLZO shell can form a homogeneous epitaxial interface with the LLZO electrolyte, suppressing side reactions and lithium dendrite formation. This conductive agent is prepared via electrospinning, gradient carbonization, and hydrothermal methods, achieving simultaneous nitrogen doping and pore formation with a single additive. The process is controllable, suitable for silicon-carbon anodes, and can reduce interfacial impedance, improving battery initial efficiency, cycle life, and fast-charging performance.

This invention discloses a lanthanum-doped PCN / MXene composite nanofiber, using La as the dopant element. The composite nanofiber is composed of zero-dimensional TiO₂ nanoparticles derived from MXene nanosheets, La-based species, and one-dimensional porous nitrogen-doped carbon (PCN) nanofibers. The TiO₂ nanoparticles contain anatase and rutile phases, forming a biphase TiO₂ heterostructure. The composite nanofiber exhibits a reflection loss value below -10 dB. The preparation method includes the following steps: 1. Preparation of MXene nanosheets; 2. Preparation of lanthanum-doped PCN / MXene composite nanofibers. The mass ratio of lanthanum nitrate hexahydrate to MXene nanosheets is 1:1; the mass ratio of polyacrylonitrile to MXene nanosheets is 4:1. The resulting composite nanofiber, with a matching thickness of 1.95 mm, exhibits a reflection loss value of -61.55 dB and an effective absorption bandwidth of 5.7 GHz (12.3–18.0 GHz).

This invention relates to the field of controllable preparation of carbon nanotube composite macrostructures, specifically a method for preparing carbon-coated ultrafine high-entropy alloy nanowire / carbon nanotube composite macrostructures. The method uses high-quality carbon nanotube macrostructures as a carrier, employing a wet chemical method to grow ultrafine high-entropy alloy nanowires on a carbon nanotube network. Rapid heating carbonizes the surfactants adsorbed on the ultrafine nanowires to form a nitrogen-doped graphite carbon layer. This carbon layer connects the nanowires and carbon nanotube bundles to form an integrated composite macrostructure. During the preparation of the ultrafine high-entropy alloy nanowires, the composition, morphology, carbon layer thickness, crystallinity, and nitrogen doping amount of the ultrafine high-entropy nanowires are controlled by altering the wet chemical synthesis conditions and heat treatment processes. The prepared carbon-coated ultrafine high-entropy alloy nanowire / carbon nanotube composite macrostructure can be directly used as a hydrogen evolution electrode in water electrolysis, exhibiting both high activity and high stability, and is expected to find applications in hydrogen production through water electrolysis.

The application belongs to the technical field of diamond material, and particularly relates to a preparation method of HD-NV color center diamond based on CVD technology and application thereof. The application first selects homo- or hetero-substrates with hexagonal structure and carries out pretreatment, deposits nitrogen-doped hexagonal diamond film on the surface of the substrates through low-temperature MPCVD, uniformly generates carbon vacancies through low-temperature electron irradiation, generates NV color centers through low-temperature annealing, and finally carries out post-treatment to obtain HD-NV color center diamond samples. The application grows hexagonal diamond film through low-temperature MPCVD by selecting homo- or hetero-substrates with hexagonal structure, applies the same low-damage doping and activation strategy, adopts room-temperature electron irradiation as a main vacancy manufacturing method, and adopts low-temperature mild annealing mode to obtain NV color centers with higher crystal quality and longer coherence time, and finally prepares an NV color center array with large area, high uniformity and high duty cycle.

The application discloses petroleum pitch-based composite porous carbon and a preparation method and a super capacitor thereof, and belongs to the technical field of super capacitor electrode materials, and the method comprises the following steps: ball-milling blocky petroleum pitch and a dispersing agent together, then screening and drying to obtain petroleum pitch powder; then mixing and grinding the petroleum pitch powder with phenolic resin and multi-walled carbon nanotubes, adding a grinding aid, uniformly grinding, compacting, pre-carbonizing under a protective atmosphere, cooling, and obtaining a pre-carbonized product; uniformly mixing the pre-carbonized product with potassium hydroxide, carbonizing and activating under a protective atmosphere, cooling, and obtaining a crude product; sequentially performing acid washing, water washing and alcohol washing on the crude product, and drying to obtain petroleum pitch-based composite porous carbon. The composite porous carbon has the advantages of a high specific surface area micropore dominant structure, a low resistivity three-dimensional conductive network and nitrogen-doped pseudo-capacitance activity, and the synergistic improvement of the energy density, the power density and the cycle stability of the super capacitor electrode material is realized.

The application provides a nitrogen-doped carbon material and a preparation method and application thereof. The method comprises the following steps: S1, purifying a coal raw material through acid washing, and then washing the coal raw material to neutral to obtain a coal-based precursor; S2, performing a hydrothermal reaction on the coal-based precursor and a saccharide compound in water, so that carboxyl functional groups of the coal-based precursor react with hydroxyl functional groups of the saccharide compound, and then drying the reaction product to obtain a composite precursor; S3, performing pyrolysis on the composite precursor to obtain a pyrolysis product; S4, performing nitrogen doping on the pyrolysis product to obtain a nitrogen-doped intermediate; and S5, performing carbonization on the nitrogen-doped intermediate to obtain the nitrogen-doped carbon material. The method provided by the application first washes the coal, then completes crosslinking of the coal and the saccharide compound in a hydrothermal process, then further stabilizes the structure in a subsequent pyrolysis stage, and then performs nitrogen doping and carbonization. The preparation method is simple, the prepared carbon material has few surface defects, and the reversible discharge specific capacity and the first coulombic efficiency are obviously improved.

This invention belongs to the field of semiconductor materials technology, and particularly relates to a method for growing high-purity silicon carbide single crystals. The invention involves assembling silicon carbide powder and a seed crystal in a graphite crucible and applying a vacuum. Before growth, the seed crystal is thermally etched at a controlled temperature of 1500–2000 °C, a pressure of 10–50 mbar, and a time of 0.5–5 h, causing preferential volatilization of silicon components on the seed crystal surface to form a partially graphitized carbon-rich layer that retains step information. Single crystal growth is then performed at 2050–2200 °C and 1–10 mbar. This invention utilizes the carbon-rich layer to increase the nitrogen doping barrier, effectively suppressing nitrogen impurities, without requiring extreme high vacuum and ultra-high growth temperatures, and yields a crystal substrate with a nitrogen concentration <1×10⁻⁶. 15 cm ‑3 Resistivity ≥ 1×10 11 Ω·cm, absorption coefficient ≤0.09 cm ‑1 Total dislocation density < 1400 cm ‑2 It has important application value in the fields of microwave radio frequency devices and optics.

This invention belongs to the field of porous carbon materials technology, specifically relating to nutshell-based nanofiber nitrogen-doped porous carbon materials, their preparation methods, and applications. The preparation method of the nutshell-based nanofiber nitrogen-doped porous carbon materials in this invention is simple and environmentally friendly, using no organic reagents and only a small amount of alkali or acid once. The nitrogen doping effect of the nutshell-based nanofiber nitrogen-doped porous carbon materials in this invention is uniform, and the content can be easily controlled during preparation. The nutshell-based nanofiber nitrogen-doped porous carbon materials in this invention possess a rich hierarchical porous structure due to the synergistic effect of the activator and nitrogen doping. These characteristics and advantages ensure that the prepared nutshell-based nanofiber nitrogen-doped porous carbon materials, when used as a negative electrode in lithium-ion batteries, exhibit higher capacity and excellent rate performance, while also possessing good cycle stability.

A method of forming a nitrogen-doped silicon substrate by doping nitrogen in an edge portion of a base substrate including a central portion and an edge portion is provided. The method includes: providing a first mask on a surface of the base substrate to cover a central portion and an inner edge portion, and to expose an outer edge portion; performing a primary doping operation of doping nitrogen on the outer edge portion while the first mask is on the surface of the base substrate; providing a second mask on the surface of the base substrate to cover the central portion, and to expose the outer edge portion and the inner edge portion; performing a secondary doping operation of doping nitrogen on the outer edge portion and the inner edge portion while the second mask is on the surface of the base substrate.