49results about How to "Controllable specific surface area" patented technology

The invention relates to an oxide of manganese, and in particular discloses high-purity trimanganese tetroxide and a preparation method thereof, wherein the Mn content in the high-purity trimanganese tetroxide is larger than 71.5 percent, and the S content is smaller than 0.03 percent. The preparation method thereof comprises the following steps of: 1. firstly dissolving high-purity manganese sulfate into water to obtain a manganese sulfate solution, then neutralizing the manganese sulfate solution with ammonia water, using the pH value of a neutralization system reaching 9.0-10.0 as the end point of a neutralization reaction, filtering, and rinsing to obtain a manganese hydroxide suspension; 2. introducing air into the manganese hydroxide suspension prepared in the step 1 at the temperature of 45-85 DEG C for oxidation, and filtering, rinsing and drying to obtain the high-purity trimanganese tetroxide after the manganese hydroxide in an oxidation system is completely converted into trimanganese tetroxide. The high-purity trimanganese tetroxide has the advantages of lower impurity content, good quality, controllable specific surface area, low preparation cost and the like.

The invention provides an eutectic high-entropy oxide powder material and a preparation method thereof, and belongs to the technical field of high-entropy oxide powder materials. The molecular formulaof the eutectic high-entropy oxide is Mn<x>(CoMgNiZn)<1-x>O (the value of x is 0.1-0.7). The proportion of a rock salt phase and a spinel phase in the eutectic high-entropy oxide is adjusted by changing the proportion of metal cations, so that certain physical and chemical properties are customized, and certain special use requirements are met. Meanwhile, the eutectic high-entropy alloy powder material is prepared by adopting a solution combustion synthesis method with simple reaction process, and liquid-phase material blending is adopted in the preparation process, so that the raw materialsare uniformly mixed at a molecular level, the uniformity of final product composition and microstructures is ensured, and the specific surface area and grain size of the prepared eutectic high-entropyoxide powder material are controllable.

The invention relates to a method for a fabricating porous TiO2 thin film by utilizing nano-crystalline TiO2 hydrosol, belonging to the technical field of fabrication process of inorganic metal oxide porous thin film. The fabricating steps of the method are as follows: (1), preparation of nano-crystalline TiO2 hydrosol: titanium salt used as raw material is complexed with ammonia water, extraction filtered, washed, and dissolved in different solvents, and then H2O2 is added thereinto to dissolve colloid to obtain different crystallization results; the sol is transferred to a high-pressure reaction kettle, crystallized for 8-15 hours at temperature of between 100 and 200 DEG C, and extraction filtered and ultrasonic dispersed in water to obtain nano-crystalline TiO2 hydrosol; (2), fabrication of the porous TiO2 thin film: the porous thin film is obtained by directly coating the hydrosol onto a matrix at low temperature. The TiO2 hydrosol prepared by the invention has high crystallization degree, good dispersity, and controllable sol shape; surface of the porous thin film is flat and even with good adhesion. The porous TiO2 thin film can be applied to fields of photocatalysis, photodetector and solar battery and the like.

The invention discloses a method for preparing iron phosphate with a micro/nano structure. The method comprises the following steps of: guiding solution of ferrous sulfate, phosphoric acid and an oxidant into a reaction container respectively; performing oxidation reaction for 2 to 5 hours and then adding a water-soluble nonionic surfactant in an amount which is 10 to 0.05 weight percent of the total amount of the ferrous sulfate and the phosphoric acid; heating to the temperature of between 50 and 100 DEG C; performing turbulent circulation for 20 to 60 minutes, then adding 5 to 20 weight percent of solution of sodium hydroxide and controlling pH of a reaction system to be 2.0 to 4.5 on line; after alkali is added, continuously performing the turbulent circulation for 20 to 60 minutes, standing and aging for 120 to 600 minutes and separating; and washing a product with pure water until the pH is 5 to 7, drying the product and performing heat treatment on the surface of the product. By the method, a near-spherical iron phosphate nanocluster with high fluidity and dispersibility and controllable specific surface area is prepared; the size of the primary particles is less than 100nm; the size of cluster particles is regulated and controlled within a range of between 200nm and 2 microns; and the product can be used for preparing lithium iron phosphate serving as a positive material of a lithium ion battery and used in the fields such as food additives, biomedicine and the like.

The invention relates to a preparation method of a polyvinyl alcohol/ZIF-8 porous composite material, and belongs to the field of porous materials. Polyvinyl alcohol is used as a polymer material andis compounded with ZIF-8, and the polyvinyl alcohol/ZIF-8 porous composite material is prepared by adopting an ice template method and a freeze-drying technology. The preparation process is simple andis short in time and the ZIF-8 is uniformly dispersed. In the polyvinyl alcohol/ZIF-8 porous composite material prepared by an ice template method, ZIF-8 particles are adhered to a polyvinyl alcoholporous material skeleton with a macroporous structure; as the polyvinyl alcohol porous material has an open pore structure, the inherent pore structure of ZIF-8 particles cannot be blocked, and therefore the porous composite material with the large specific surface area can be prepared. ZIF-8 nano-particles with different specific surface areas can be prepared by changing the preparation method ofthe ZIF-8 nano-particles; meanwhile, the specific surface area of the porous composite material can be controlled by changing the mass ratio of the ZIF-8 particles to the polyvinyl alcohol.

The invention provides a self-template method for preparing hollow carbon spheres. The method comprises the steps as follows: phosphonitrilic chloride trimer and a comonomer are dispersed in an organic solvent, then an acid-binding agent is added, the mixture reacts under the ultrasonic assistance condition for 2-6 h, after the reaction ends, centrifugation and washing are performed, and solid polyphosphazene microspheres are obtained; the polyphosphazene microspheres are transferred to a carbonization furnace and calcined at the high temperature under the shielding of inert gas, and the hollow carbon spheres are obtained. The hollow carbon spheres with good monodispersity, uniform particle size and controllable wall thickness and particle size are prepared quickly with the self-template method. No additional templates are required in the whole preparation process, and the preparation method is simple and environmentally friendly and facilitates mass production.

The invention relates to the field of SO2 gas sensors and discloses a solid electrolyte SO2 gas sensor and a manufacturing method thereof. The solid electrolyte SO2 gas sensor comprises a silicon substrate, and a SiO2 insulated layer, a conductive film, a Sn/SnF2 thin film, a LaF3 solid electrolyte thin film and a Pt net which are arranged on the silicon substrate in sequence. The conductive film is connected with a first lead; and the Pt net is connected with a second lead. In the technical scheme, the conductive film is an Al film; and the manufacturing method adopts an MEMS (Micro Electromechanical System) technology and has simple process and convenient realization.

The invention discloses a preparation method of a one-dimensional mesoporous Co nanowire array, which comprising the following steps: preparing a precursor solution at room temperature by mixing 0.5-0.7g of PEP-POO-PEP (P123) which is an addition polymer of polypropylene glycol and ethylene oxide, 0.9-3g of tetraethyl orthosilicate and 0.4g of 38 wt% muriatic acid together; in an AAO (anodised aluminium) template, synthesizing SBA (mesoporous silica) nanofibers, wherein the mesoporous canals of the SBA (mesoporous silica) nanofibers are parallel to AAO canals; preparing electrodeposit liquid in the ratio of 2-4g of Co(CH3COO)2 : 1-3g of H3BO3; taking an aluminium base AAO-SBA composite mesoporous template as a working electrode and taking graphite as an auxiliary electrode, and controlling electrode density between 0.5-1.5 mA/cm2 and electrodepositing for 1.0-1.5h to obtain a Co nanowire with the width of about 200nm, wherein the Co nanowire consists of 4-6mn mesoporous Co nano rods. The invention adopts a simple electrochemical method to generate Co nano structures in AAO-SBA composite mesopores for the first time; and the growth direction of the crystals of the nano structures is controlled by the mesoporous canals. The invention has simple equipment, can be operated easily and is suitable to the industrial production.

The invention discloses a solid electrolyte gas sensor and a temperature compensation method based on a Pt reaction electrode. The sensor comprises a Pt reaction electrode and a solid electrolyte wafer, wherein one end face of the solid electrolyte wafer is connected with a reference electrode with a third lead. The sensor is characterized in that the Pt reaction electrode is prepared on the other end face of the solid electrolyte wafer by adopting an MEMS process, the Pt reaction electrode adopts a band structure, two ends of the Pt reaction electrode are respectively arranged on opposite edges of the end faces of the solid electrolyte wafer, which pass through the diameter direction, and are respectively connected with a first lead and a second lead; and the band electrode is tortuously distributed along the plane of the end faces of the solid electrolyte wafer. A resistor signal converting circuit is connected between the first lead and the second lead and converts the resistance value change of the Pt reaction electrode caused by the temperature change into electrical signals to be input a signal processing circuit, and electromotive force signals obtained by primary detection through the signal processing circuit and reflecting the gas volume percent are compensated so that the influence of the temperature change to the sensor property is eliminated.

The invention relates to one-dimensional single crystal LaFeO3 nanorods and preparation thereof, belonging to the technical field of LaFeO3 nanocrystals. The preparation method comprises the following steps: preparing Fe2O3 nanorods by a hydrothermal synthesis process, dissolving lanthanum nitrate hexahydrate in deionized water, adding the Fe2O3 nanorods under stirring conditions to obtain a template, dropwisely adding a 10% KOH solution under stirring conditions until the pH value of the solution is 10 or so, carrying out ultrasonic treatment for 10-15 minutes, transferring into a teflon-lined autogenous pressure kettle until the volume degree of filling is 80%, carrying out constant-temperature treatment at 180 DEG C for 12 hours, carrying out vacuum filtration,, washing with deionized water three times, washing with anhydrous ethanol three times, drying at 80 DEG C for 12 hours, heating from room temperature to 650-750 DEG C in a muffle furnace in an air atmosphere at the rate of 1 DEG C/minute, and keeping the temperature for 4 hours to obtain the one-dimensional single crystal LaFeO3 nanorods. The raw materials are cheap and accessible; the preparation process is simple; and the product shape is controllable.

The invention discloses scandium-and-cerium-doped zirconium oxide ultrafine powder and a preparation method thereof. According to the invention, CTAB is used as a dispersing agent to prepare scandium-and-cerium-doped zirconium oxide ultrafine powder. The preparation method comprises the following steps: firstly, converting a Zr(OH)4 precipitate into monoclinic zirconium oxide by adopting a hydrothermal method to obtain a tetragonal zirconium oxide precursor with enough nucleation core particles; and then conducting calcining to enable tetragonal zirconium oxide crystals to grow into proper particles, thereby preparing the scandium-and-cerium-doped zirconium oxide ultrafine powder with uniform particle size, small particle size and high specific surface area. The preparation method is simple in process and easy for large-scale industrial production.

The invention provides a preparation method of magnesium hydroxide powder. The method comprises the following step: pulse current is applied in a reaction system when light calcined magnesia is utilized to prepare the magnesium hydroxide powder via hydration reaction. The magnitude of the pulse current applied in the reaction system is 5-1,000 A, and the used pulse frequency is 50-2,000 Hz. By adjusting the magnitude of the pulse current and the pulse frequency, the specific surface area, average particle size and microstructure and morphology of the magnesium hydroxide are controlled by the invention. Compared with the prior art, the preparation method provided by the invention has the following advantages: the process is simple, the cost is low, and the specific surface area, average particle size and microstructure and morphology of the magnesium hydroxide are easy to control.

The invention relates to a preparation method of a petroleum-degrading microbial agent and belongs to the technical field of petroleum pollution remediation. According to the method, grapefruit peel and activated carbon are subjected to pyrolysis treatment to serve as a microbial agent carrier, a large amount of cellulose is contained in a white flocculent layer in the grapefruit peel, the grapefruit peel also has the characteristics of multiple pores and a large pore diameter and has a compact structure, the network structure is not obvious, oil products are adsorbed to a certain extent, thethree-dimensional network structure of the pyrolyzed grapefruit peel is more obvious, large and small pores are communicated in a staggered manner, and rapid oil absorption is facilitated, and the pore diameter is obviously increased compared with that before pyrolysis, so that the improvement of oil absorption is facilitated; due to the fact that an artificial carrier has the advantages of controllable specific surface area, pore size distribution, good mass transfer performance and the like, the artificial carrier can be better matched with specific microbes and complex pollutants so as to obtain better immobilization effect and repair performance; biochar has strong petroleum adsorption capacity, achieves the enrichment and degradation integration of pollutants and is beneficial to theimprovement of the soil remediation effect.