57results about How to "Efficient doping" patented technology

The present invention is related to the preparation of a metal lattice-doping catalyst in an amorphous molten state, and the process of catalyzing methane to make olefins, aromatics, and hydrogen using the catalyst under oxygen-free, continuous flowing conditions. Such a process has little coke deposition and realizes atom-economic conversion. Under the conditions encountered in a fixed bed reactor (i.e. reaction temperature: 750˜1200° C.; reaction pressure: atmospheric pressure; the weight hourly space velocity of feed gas: 1000˜30000 ml/g/h; and fixed bed), conversion of methane is 8-50%. The selectivity of olefins is 30˜90%. And selectivity of aromatics is 10˜70%. There is no coking. The reaction process has many advantages, including a long catalyst life (>100 hrs), high stability of redox and hydrothermal properties under high temperature, high selectivity towards target products, zero coke deposition, easy separation of products, good reproducibility, safe and reliable operation, etc., all of which are very desirable for industrial application.

An n-type diamond epitaxial layer 20 is formed by processing a single-crystalline {100} diamond substrate 10 so as to form a {111} plane, and subsequently by causing diamond to epitaxially grow while n-doping the diamond {111} plane. Further, a combination of the n-type semiconductor diamond, p-type semiconductor diamond, and non-doped diamond, obtained in the above-described way, as well as the use of p-type single-crystalline {100} diamond substrate allow for a pn junction type, a pnp junction type, an npn junction type and a pin junction type semiconductor diamond to be obtained.

A reactor configuration comprises an inlet section I, a preheating section II, a transition section III, a reaction section IV and an outlet section V; except for the preheating section II and the reaction section IV, the existence of the inlet section I, the transition section III and the outlet section V depends on reaction conditions; and the process realizes no coke deposition synthesis of methane and high selectivity synthesis of ethylene. The methane conversion rate is 20-90%; ethylene selectivity is 65-95%; propylene and butylene selectivity is 5-25%; aromatic hydrocarbon selectivity is 0-30%; and coke deposition is zero.

The invention discloses nitrogen-doped carbon aerogel prepared by utilizing natural-structure macromolecular nano-fiber aerogel. A biomass polysaccharide structural macromolecular material is prepared into cellulose aerogel through a mechanical method, a chemical oxidization pre-treatment method and an enzyme pre-treatment method, and is then treated in a nitrogen-rich atmosphere by a high-temperature pyrolysis method. With the adoption of the nitrogen-doped carbon aerogel, the utilization value of the biomass polysaccharide structural macromolecular material is improved, and novel concept and method are provided for efficiently utilizing carbon material resources.

The application discloses a preparation method for a graphene field emitting cathode. The preparation method comprises the following steps of: adding graphene and metal soluble inorganic salts in an organic solvent in a preset ratio to prepare graphene electrophoresis solution with positive charges; using a conductive substrate as a cathode, placing an anode and the cathode in the graphene electrophoresis solution, externally adding an electric field to enable the graphene with positive charges to move towards the direction of the cathode, and deposit on the cathode, so as to obtain a graphene film doped with metal particles; drying the graphene film to obtain the graphene field emitting cathode. The application further discloses a graphene field emitting cathode. The preparation method and the graphene field emitting cathode disclosed by the application are capable of improving the electrical contact characteristic between graphene and a substrate, and improving conduction performance; meanwhile, due to the metal nano-particles, the roughness of the graphene surface is improved, the local electric field intensity of the graphene surface is enhanced, the turn-on electric field of the graphene field emitting cathode is remarkably reduced, and the field emitting current is increased.

In semiconductor devices, a semiconductor device is provided which is high in reliability while suppressing changes in characteristics such as threshold voltages. In a semiconductor device which has a gate dielectric film above a semiconductor substrate and also has above the gate dielectric film a gate electrode film made of silicon germanium chosen as its main constituent material, or alternatively in a semiconductor device which has beneath the gate dielectric film a channel made of silicon as its main constituent material and which has below the channel a channel underlayer film made of silicon germanium as its main constituent material, a specifically chosen dopant, such as cobalt (Co) or carbon (C) or nitrogen (N), is added to the gate electrode and the channel underlayer film, for use as the unit for suppressing diffusion of germanium in the gate electrode or in the channel underlayer film.

A method for manufacturing a Group III nitride semiconductor layer according to the present invention includes a sputtering step of disposing a substrate and a target containing a Group III element in a chamber, introducing a gas for formation of a plasma in the chamber and forming a Group III nitride semiconductor layer added with Si as a dopant on the substrate by a reactive sputtering method, wherein a Si hydride is added in the gas for formation of a plasma.

A highly versatile material for mid-infrared filters is provided by precisely controlling the absorption intensity of titanium oxide in an infrared region. A rutile-type titanium oxide crystal is produced by a method including a step (I) of dispersing or dissolving a complex of an amino group-containing basic polymer and a transition metal ion in an aqueous medium, a step (II) of obtaining a composite having a polymer/titania layered structure in which the complex of the amino group-containing basic polymer and the transition metal ion is sandwiched between layers of titania, by causing a hydrolysis reaction between the aqueous dispersion or aqueous solution prepared in the step (I) and a water-soluble titanium compound in the aqueous medium, and a step (III) of calcining the composite having the layered structure in an air atmosphere at a temperature of 650° C. or higher to dope a surface of a titanium oxide crystal with the transition metal ion and simultaneously to cause growth into a rutile-type crystal phase. The thus-obtained crystal can be used for mid-infrared filters.

A method for fabricating a hydrophilic aluminum surface includes: an activation step of preparing doped aluminum having an activated surface through doping treatment on a part or whole of an aluminum surface with applying reactive gas thereto; and a structure forming step of preparing a hydrophilic aluminum surface through oxidizing treatment on the doped aluminum to have nano-patterns comprising nano-protrusion structures on the aluminum surface. Hydrophobic aluminum can be fabricated into artificially hydrophilic or super-hydrophilic aluminum, and the hydrophilic aluminum surface body that does not have an aging effect and has long-lasting hydrophilicity can be provided.

Silicon single crystal is pulled by the Czochralski method, using an As dopant comprising a mixed sintered compact of arsenic and silicon, the molar ratio of silicon being not smaller than 35% and not greater than 55% relative to arsenic.

The invention discloses a multi-element metal phosphorus-doped electrocatalyst based on binary LDH derivation. A preparation method for the multi-element metal phosphorus-doped electrocatalyst comprises the following steps: 1) mixing ethylene glycol and deionized water to obtain a mixed solvent; 2) dissolving a cobalt salt, a molybdenum salt and urea in the mixed solvent, and carrying out uniformstirring to obtain a solution A; 3) adding hydrophilic carbon cloth into the solution A, and carrying out a reaction to obtain CoMo-LDH-CF; and 4) placing the CoMo-LDH-CF material in a tubular furnace, placing a magnetic boat filled with sodium hydrogen hypophosphite at the upper stream of the tubular furnace, raising a temperature in an inert atmosphere, keeping the temperature, and carrying outcooling to room temperature to obtain the binary LDH-derived metal phosphorus-doped electrocatalyst CoMo-P-CF containing double metals, i.e., Co and Mo. After the cobalt-molybdenum bimetallic LDH material growing on the carbon cloth is synthesized by a hydrothermal method, the cobalt-molybdenum bimetallic LDH material is subjected to high-temperature heat treatment and reacts with sodium hydrogenhypophosphite to obtain a Co-and-Mo-containing bimetallic binary phosphorus-doped electrocatalytic material with a large specific surface area and a regular structure, and the material has the advantages of accurate and controllable composition and favorable conductivity.

The invention discloses a preparation method of nano-molybdenum powder doped with yttrium oxide nano-particles. The preparation method comprises the following steps of 1, dispersing commercial micron-sized molybdenum trioxide and carbon nano-particles in a solution, and conducting drying by distillation to obtain composite powder; 2, spraying the ultrafine/nanometer yttrium salt liquid drops intothe composite powder, and conducting drying to obtain a yttrium salt-containing mixture; 3, carrying out segmented heat preservation and reduction on the yttrium salt-containing mixture to obtain ultrafine doped MoO2; and 4, conducting reduction on the ultrafine doped MoO2 by hydrogen to obtain nano-molybdenum powder doped with yttrium oxide nano-particles. The invention also provides an application of the nano-molybdenum powder doped with the yttrium oxide nanoparticles to sintering preparation of a nano-structure oxide dispersion strengthened molybdenum alloy. According to the preparation method, two-step reduction is combined with preparation of the composite powder, so that the nucleation number of a reduction product is increased, the granularity of the reduction product is refined, the granularity of the doping yttrium oxide nano-particles and molybdenum powder is regulated and controlled, and the raw material cost is reduced. The application method is simple and easy to implement.

The invention discloses copper and silver co-doped nano-zinc oxide used as a photocatalyst, and a preparation method of the copper and silver co-doped nano-zinc oxide. A sol-gel method is adopted, metal alkoxides (copper acetate and zinc acetate) and acid salt (silver nitrate) are used as raw materials and dissolved in a solvent to form gel with a certain spatial structure, finally drying and heattreatment processes are carried out, and thus the copper and silver co-doped nano-zinc oxide uniform in particle size and high in purity can be prepared. Copper and sliver are doped in zinc oxide, sothat the production cost is reduced and industrial production is achieved while the catalytic activity of the nano-zinc oxide is improved.

The invention discloses organic optical iridium coordination compounds and application thereof in an organic electro-generated white or orange optical device. The orange optical iridium coordinate compounds have a structural formula as formula 1 or formula 2 which is shown in the specification, wherein R1 can be trifluoromethyl or pentafluoroethyl, R4 can be trifluoromethyl or pentafluoroethyl or R1=R4, R2 is selected from hydrogen, methyl, ethyl and halogen or halogen-substituted methyl or ethyl, R3 is independently selected from hydrogen, methyl, ethyl, halogen or halogen-substituted methyl or ethyl or R2=R3, and the halogen is fluorine, chlorine, bromine or iodine. The invention has the advantages as follows: a fluorine-containing modified iridium coordination compound can be used for effectively lowering vibrating frequency, reducing non-radiative transition and increasing electroluminescence efficiency; a film prepared by using a fluorine atom-containing modified coordination compound has better feature; self-quenching behaviors are restrained by steric hindrance of CF3; and charge transfer balance performance is increased by very good current carrier transmission performance, so that an efficient doped organic electro-generated luminescent device can be manufactured.

The invention relates to an efficient gallium oxide doping method based on unbalanced laser plasma. The efficient gallium oxide doping method comprises the following steps of: carrying out surface pretreatment on a gallium oxide substrate; and growing a doped gallium oxide epitaxial layer on the gallium oxide substrate after surface pretreatment by using a pulse laser deposition process. According to the efficient gallium oxide doping method based on unbalanced laser plasma, a pulse laser deposition process is adopted, the doped gallium oxide epitaxial layer is grown on the gallium oxide substrate, and a doped gallium oxide target material is induced to be plasmonized based on laser induction, so that impurities do not enter gallium oxide in an atomic form, instead, the impurities enter the gallium oxide in a non-equilibrium plasma state, thus the doping activation temperature can be reduced, the activation efficiency of doped carriers is greatly improved, efficient doping of gallium oxide is realized, the doping efficiency and free carrier concentration of Ga2O3 are improved, an efficient doped gallium oxide epitaxial layer film is formed, and the performance of subsequent devices is improved.