32results about How to "Promote in situ growth" patented technology

The invention provides a preparing method of Si-B-C-N ceramic with laminated BN(C) grains toughened and belongs to the technical field of preparing methods of Si-B-C-N ceramic. The method comprises the steps that 1, cubic silica powder, hexagonal boron nitride powder, graphite powder and lanthanum hexaboride powder are weighed according to the molar ratio and the mass ratio to be served as raw materials for standby application; 2, the raw materials weighed in the step 1 are put into a ball-milling tank, and high-energy ball milling is carried out under the protection of argon atmosphere, so that Si-B-C-N ceramic composite powder containing LaB6 is obtained; the ball material mass ratio is (10-90):1, the ball-milling diameter is 5-9 mm, and ball-milling time is 10-60 h; and 3, the ceramic composite powder obtained in the step 2 is subjected to spark plasma sintering to obtain a Si-B-C-N ceramic material with the laminated BN(C) grains toughened. The Si-B-C-N ceramic material obtained through the preparing method has high breaking tenacity, and the possibility of catastrophic fracture of the ceramic is reduced. The added rare earth compound LaB6 contributes to in-situ growth of the laminated BN(C) grains.

The invention discloses a method for preparing spherical aluminum nitride powder under the assistance of high atmospheric pressure and a fluoride additive, belonging to the technical field of preparation of non-oxide ceramic powder materials. The method concretely comprises the following steps: evenly mixing aluminum oxide, a carbon source and fluoride additive through a ball-milling technology, drying and then putting in a graphite crucible, transferring into an atmospheric-pressure sintering furnace, performing carbon thermal reduction reaction for 1-6 hours in the nitrogen atmosphere, and maintaining the pressure of nitrogen to be 0.2-2MPa, and the reaction temperature to be 1650-1900DEG C; and after the reaction is completed, putting the obtained product into a muffle furnace, carrying carbon emission for 1-5 hours under the condition of 500-750DEG C, thus obtaining the spherical aluminum nitride powder. The prepared aluminum nitride powder has the characteristics of being high in spherical degree, smooth in the surface, even for particle size distribution and the like, the intermediate particle size is 3-10mu m, and the spherical degree achieves more than 80%; the spherical aluminum nitride powder is very suitable as high-heat-conducting aluminum nitride filler; in addition, the technological method is simple, the raw material cost is relatively low, and large-scale industrial production can be realized.

The invention relates to a ZnO nanocluster gas-sensitive sensor with FTO conductive glass subjected to laser etching treatment as an electrode element, and belongs to the technical field of gas sensors. The gas-sensitive sensor consists of two parts, namely a gas-sensitive electrode element and a gas-sensitive material, and is characterized in that the gas-sensitive electrode element is obtained by carrying out laser etching treatment on the FTO conductive glass with the specific pattern and line width, the etched pattern is in an interdigital shape, the width of interdigital stripes is 300-500 mum, and the interval of the interdigital stripes is 20-80 mum; the gas-sensitive material is a ZnO nano-cluster array of a hexagonal wurtzite structure, the diameter of a nanowire is 70-100 nm, andthe length of the nanowire is 2-3.5 mum. The FTO gas-sensitive electrode element has the advantages of low cost, good stability, easiness in in-situ growth of the gas-sensitive material and the like;the sensor has the advantages of low cost, simple process, excellent gas sensitivity, good stability and the like, shows excellent response capability to gases such as ethanol, methanol, hydrogen sulfide and the like, and is a novel gas-sensitive sensor with wide development and application prospects.

The invention relates to a method of preparing a PbTiO3 nanotube array film in situ by utilizing the hydrothermal method. The method adopts phosphoric acid, hydrofluoric acid, lead acetate and deionized water as raw materials. Firstly, a TiO2 nanotube array film is prepared on the titanium foil sheet through anodic oxidation; and secondly, under the condition that the lead acetate aqueous solution with a molarity of 0.00001 to 10 mol per liter is used as the medium, the TiO2 nanotube array film is adopted as the template, and the hydrothermal reacting solution with a volume percentage of 20 to 90 percent, i.e. the lead acetate aqueous solution is added in and kept constant for 0.5 to 50 hours at a temperature of 150 to 300 DEG C and then the PbTiO3 nanotube array film is finally obtained. The method is fit for manufacturing electronic devices of various types and has a far-ranging application prospect in the industrial fields of piezoelectricity, pyroelectricity and semiconductors.

A preparation method of a graphene-loaded Alpha-FeOOH sandwiched sheet layer-structure lithium ion battery negative electrode material comprises the steps of dispersing graphene oxide in deionized water to obtain a suspension liquid A; adding a ferric nitrate salt into the deionized water, and mixing with the suspension liquid A to obtain a suspension liquid B; pouring the suspension liquid B into a homogeneous phase hydrothermal reaction kettle, sealing the reaction kettle, placing the suspension liquid B in a homogeneous phase hydrothermal reaction instrument for hydrothermal reaction and naturally cooling to a room temperature to obtain a product C; respectively washing the product C with water and alcohol, and dispersing the washed product in the water to obtain a product D; and freezing and drying the product D to obtain the sandwiched sheet layer-structure graphene-loaded Alpha-FeOOH compound. Since graphene is good in conductivity and has relatively large specific area, the conductivity of Alpha-FeOOH can be remarkably improved by loading the graphene, the dispersion performance of the Alpha-FeOOH is simultaneously improved, and agglomeration is prevented. An ultrasonic assistant method and a homogeneous phase hydrothermal method are combined, the material conductivity is improved by combining the Alpha-FeOOH and the graphene, the electrochemical performance is improved, so that the battery is more stable in structure, and the cycle stability of the battery is improved.

The invention provides a preparation method of a Co1-xS-MoS2- nitrogen-doped carbon ternary composite material with double functions. The preparation method comprises the following steps: firstly, obtaining a cobalt precursor array growing on a carbon paper substrate through chemical bath deposition, and then, obtaining a cubic phase Co9S8 nanorod array through oxidation and vulcanization; dissolving molybdenum salt, dipyridyl or phenanthroline and a carbon source in an N, N-dimethylformamide solution to obtain a Mo < 5 + >-N-C precursor solution, coating the precursor solution on a substrate on which the Co9S8 array structure grows, and performing drying; and with argon or nitrogen taken as a protective gas and a carrier gas, and thesublimation S elementary substance powder as a solid evaporation source, carrying out chemical vapor deposition reaction to obtain a hexagonal-phase Co1-xS and MoS2 and NC compound array. The product obtained by the technical scheme of the invention has the advantages of low equipment requirement, low cost of required raw materials, easy control of reaction conditions, simple production process, good consistency of the formed product, small environmental pollution and the like, and can be used for multifunctional electrocatalysts of HER and OER.

The invention discloses a preparation method of a graphene-loaded iron oxide self-assembly mulberry-like structure negative electrode material of a lithium-ion battery. The method comprises the steps of dispersing graphene oxide into ethanol to prepare a suspension A; adding ferrous chloride to deionized water and then mixing with the suspension A to obtain a mixed solution B; pouring the mixed solution B into a heterogeneous hydrothermal reactor for hydrothermal reaction, after the reaction is completed, naturally cooling to a room temperature to obtain a product C; carrying out washing and alcohol washing on the product C separately, dispersing the washed product into water to obtain a product D; and freezing the product D until no liquid exists, and then putting the product D into a freezing dryer to obtain a dried sample, namely the final graphene-loaded iron oxide self-assembly mulberry-like structure negative electrode material of the lithium-ion battery. In-situ growth of iron oxide on the graphene surface is achieved to form a graphene-loaded structure by using coordination of a ferric salt and the graphene oxide; and the preparation method is simple in experimental method, low in cost and easy to implement.

The invention discloses a spraying process for metal part surface treatment. The spraying process comprises the following steps: 1, surface excitation treatment, wherein a metal part is firstly placed in a corona field to be treated for 10-15 minutes, the field intensity of the corona field is 220-250 KV/m, then plasma treatment is adopted, and the treatment is completed; and 2, arrangement of active point locations. According to the spraying process, active medium points are distributed on the surface of the metal part and irradiated by pulsed ion beams, the activity of rare earth lanthanum oxide is excited, and in-situ growth of nano silicon dioxide on the surface of the metal part is promoted, so that a large number of uniform tiny pits are formed, adsorption and bonding of a subsequent spraying layer are facilitated, and the adsorption strength of the spraying layer is improved.