5151 results about "Silver nitrate" patented technology

Methods for forming nanostructures of various shapes are disclosed. Nanocubes, nanowires, nanopyramids and multiply twinned particles of silver may by formed by combining a solution of silver nitrate in ethylene glycol with a solution of poly(vinyl pyrrolidone) in ethylene glycol. Hollow nanostructures may be formed by reacting a solution of solid nanostructures comprising one of a first metal and a first metal alloy with a metal salt that can be reduced by the first metal or first metal alloy. Nanostructures comprising a core with at least one nanoshell may be formed by plating a nanostructure and reacting the plating with a metal salt.

A process for producing a fine silver particle colloidal dispersion which can simply form conductive silver layers and antimicrobial coatings by screen printing or the like. The process is characterized by having a reaction step of allowing an aqueous silver nitrate solution to react with a mixed solution of an aqueous iron(II) sulfate solution and an aqueous sodium citrate solution to form an agglomerate of fine silver particles, a filtration step of filtering the resultant agglomerate of fine silver particles to obtain a cake of the agglomerate of fine silver particles, a dispersion step of adding pure water to the cake to obtain a first fine silver particle colloidal dispersion of a water system in which dispersion the fine silver particles have been dispersed in the pure water, and a concentration and washing step of concentrating and washing the first fine silver particle colloidal dispersion of a water system.

A nano-Ag sol is prepared through dispersing the protecting colloid solution in silver nitrate solution, adding reducer solution, and redox reacting.

The invention discloses a quick and efficient synthesis method for silver nanowires. The method comprises the following steps of: 1) introducing inert gas into a reactor, adding 2 volume parts of glycol into the reactor, and stirring, heating, condensing and refluxing the glycol; quickly adding 1 volume part of glycol solution of silver nitrate at molar concentration of between 0.1 and 0.5m into the reactor; slowly dropwise adding 1 to 2 volume parts of PVP at molar concentration of between 0.15 and 0.75m and 4 to 32 mu m of glycol solution of MnCl2 at the same time; and reacting and cooling the mixture to the room temperature to obtain reaction mother liquor of the silver nanowires; and 2) transferring the reaction mother liquor of the silver nanowires into a centrifugal tube; adding acetone into the centrifugal tube and performing centrifugal separation to remove supernatant and retain precipitate; adding de-ionized water or ethanol into the centrifugal tube and performing centrifugal separation to remove the supernatant and retain precipitate, and repeating the operation for 1 to 3 times; and extracting and dispersing the precipitate with ethanol to obtain the silver nanowires. The method shortens the reaction time and also has high selectivity for the synthesis of the silver nanowires under conditions of high concentration.

The invention discloses a method for preparing nanometer silver lines in large batch. anhydrous silver nitrate AgNO3 with the concentration of 99.9percent, anhydrous glycol (C2H6O2) of 99.8percent and polyvinylpyrrolidone (PVP, with the molecular weight of 55,000) of 98percent are selected as the raw materials; in a microwave-assisting environment, the method of adopting the glycol to reduce the silver nitrate is adopted to prepare nanometer silver lines in large batch. By replacing the original solvent heating method with the high-heat environment created by microwave, the method not only greatly saves the reaction time but also reduces the preparing costs for the nanometer silver lines. The glycol, a moderate reducer, can slow the reaction, thus providing the time for the growth of nanometer silver lines. The method of the invention is the optimal method for preparing the nanometer silver line according to testing results by comparing the influence of micro strength, precursor concentration and microwave processing time on the appearance and size of the prepared nanometer lines. The method of the invention has low cost, is simple method and easily controlled and has high practical value in the application to the industrial production developing nanometer silver lines.

The present invention discloses the preparation process of nanometer silver solution and nanometer silver powder with polymer as stabilizer. Water soluble polymer as stabilizer in solution of 0.001-0.05 g / ml solution and silver nitrate in solution of 0.001-0.1 mol / L are compounded and reduced with water soluble reductant in solution of 0.001-0.2 mol / L to obtain nanometer silver particle of 5-100 nm size. The nanometer silver particle in solution may be further deposited and washed with sodium hydroxide solution, dried and crushed to obtain nanometer silver particle of 5-100 nm size. The prepared solution may be used in medical article, and prepared nanometer silver powder may be used widely in household appliance, plastic product, paint, etc. The present invention is environment friendly, low in cost and simple in operation, and the prepared nanometer silver particle has extremely powerful antibiotic capacity and wide antibiotic spectrum.

The invention relates to a method for preparing nanometer silver powder with accurately controlled particle size, which comprises the following steps of: taking silver nitrate as a starting material, and reacting with a precipitant to form a uniform silver-containing precursor precipitate; and adding a reducing agent for reducing the silver-containing precursor precipitate while adding a silver crystal seed to obtain simple substance silver. The obtained silver powder particle is polyhedral or almost spherical, the powder body has good dispersity and uniformly distributed particle size, and particle size of the silver powder can be accurately controlled in the range of 20-300nm by controlling crystal seed size and addition. The invention is the method for preparing water solution system of nanometer silver powder which has accurately controlled particle size and is suitable for large scale production under normal temperature and normal pressure condition. The preparation method has moderate reaction condition and is simple and convenient, and the nanometer silver powder has low cost and stable quality.

The invention provides a method for preparing silver nanometer wire with controllable wire diameter by a cation control microwave method, aiming at solving the problems of rough wire diameter, low diameter ratio and the like during preparation of the silver nanometer wire by the traditional microwave method. The method comprises the following steps of: (1) adding a mixture of silver nitrate powder and a dispersing agent into ethylene glycol and preparing a solution reaction system containing silver ions; (2) adding a cation control agent in the solution reaction system containing silver ions and evenly stirring to obtain a reaction precursor; and (3) irradiating the reaction precursor under microwave, centrifuging, ultrasonically washing and drying the solution prepared through microwave irradiation to obtain the silver nanometer wire powder with controllable wire diameter. The invention has the advantages of simple preparation method, high efficiency and low cost and ensures that the high-quality silver nanometer wire can be prepared repeatedly within wide range of reaction condition. By using a soft template method, the size of the wire diameter is controlled by using the cation control agent without introducing any impurity.

The invention discloses a method for preparing antibacterial nanometer silver colloid, belonging to the technical field of nanometer biological materials. The method uses a chemical reduction method, comprising the following steps: dissolving water-soluble protective agent in silver nitrate water solution with the concentration of 0.001-0.1mol / L, wherein the mass ratio of protective agent to silver nitrate is 0.5-10.0:1; carrying out ice bath on sodium borohydride water solution with the concentration of 0.001-0.2mol / L for 10-30min; and dropwise adding the silver nitrate water solution containing protective agent in the sodium borohydride water solution with the speed of 30-60 drop / min, stirring by a magnetic stirrer, stirring for 20-40min after dropwise adding to prepare the nanometer silver colloid with the grain size of 5-80nm, wherein the mol ratio of the sodium borohydride to the silver nitrate is 1.0-30.0:1. The nanometer silver colloid prepared by the invention has the advantages of high concentration, high stability, high dispensability, and obviously-enhanced antibacterial property.

The invention provides a preparation method of a graphene-silver nano particle composite material. A specific preparation process comprises the following steps of: preparing solution of silver ammonia at certain concentration from the solution of silver nitrate and aqueous solution of dilute ammonia, adding the prepared solution of silver-ammonia into the solution of graphene oxide which is subjected to ultrasonic processing, preheating the solution at a certain temperature for a certain time; adding an appropriate amount of glucose into the mixed solution of graphene oxide and silver ammonia, and reacting the mixed solution at the set temperature for a certain time with stirring; performing suction-filtration on a reaction product by using deionized water for many times, and then drying the product to obtain the graphene-silver nano particle composite material. The method is simple, convenient, easy, environment-friendly and efficient; and silver nano particles in the prepared composite material are distributed narrowly, have a uniform particle size (about 25 nm), can be better inserted into graphene slices and can effectively prevent aggregation of the graphene.

The invention relates to a method of preparing silver nanowire by utilization of a hydrothermal method. The steps including: directly mixing ethylene glycol PVP solution which contains metal chloride with the concentration of 0.01M-2MPVP and the concentration of 1*10M-1*10-2M with ethylene glycol silver nitrate solution with the concentration of 0.01M-1M at normal temperature, stirring the mixed solution to be uniformed mixed, obtaining mixed reaction mother solution; the volume ratio of ethylene glycol silver nitrate solution to ethylene glycol PVP solution is 1:1-10:1; the molar ratio of silver nitrate to the PVP in the mixed reaction mother solution is 1:10-10:1, and the molar ration of silver nitrate to metal chloride is 10:1-104:1; putting the mixed reaction mother solution into an reaction kettle, warming the mixed reaction mother solution to 160 DEG C - 180 DEG C to carry out reduction reaction, the silver salt in the mother solution is restored, and silver nanowire is obtained. The method of preparing silver nanowire by utilization of the hydrothermal method has the advantage of being simple and high-efficient, no need of being preheated when the preliminary reaction is carried out at the normal temperature, easy to control of reaction conditions, and especially applicable to mass production.

The invention discloses a high-efficiency graphene / silver phosphate composite visible light photocatalyst and a preparation method thereof, belonging to the technical field of composite materials and environmental management photocatalysis. The preparation method comprises the following steps: dissolving graphene oxide in water, and carrying out ultrasonic treatment to obtain a graphene oxide dispersed liquid; dissolving silver nitrate in deionized water, gradually and dropwisely adding into the graphene oxide dispersed liquid while stirring to obtain a mixed solution, uniformly stirring, and aging; dropwisely adding a prepared disodium hydrogen phosphate or sodium dihydrogen phosphate solution into the graphene oxide-silver nitrate mixed solution, continuing stirring, transferring into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to room temperature; and washing the reaction product, and carrying out vacuum drying to obtain the visible light photocatalyst. The invention has the advantages of wide material sources and simple preparation process; and the obtained composite material has the advantages of controllable structure and regular pattern, and has high-efficiency degradation effect on organic dyes rhodamine B and methylene blue with certain concentration under the visible light irradiation.

A process for synthesizing linear nano carbon array includes putting monosilicon wafer in a hydrothermal reactor containing the reacting solution of hydrofluoric acid (0.2-15 mol / L) and silver nitrate (0.05-0.10 mol / L), and reaction at 30-80 deg.C for 30-150 min to generate large-area linear nano carbon array on the monosilicon wafer. Its advantages are low reaction temp and low cost.

The present invention belongs to the field of nanometer material preparing technology, and provides a two-step silver nanometer wire synthesizing process with high form selectivity and high efficiency. Under the protection of inert gas, very dilute ethylene glycol solution of silver nitrate is first added into ethylene glycol to prepare silver crystal seed; ethylene glycol solution of silver nitrate in relatively high concentration and ethylene glycol polymer solution in the corresponding concentration and volume are then added into the reaction system with crystal seed; and through crystal growth, silver nanometer wire is obtained. By means of regulating reaction condition, the size and form of the silver nanometer wire may be controlled. The present invention has low reaction cost and high silver nanometer wire yield, and the obtained silver nanometer wire has high purity, good structure and high mechanical performance.

The invention relates to a method for preparing a length-diameter-ratio nano-silver wire by a pH-value regulation solvothermal method. The method comprises the following steps of: preparing the following ethylene glycol solution, namely an ethylene glycol solution A of silver nitrate or silver acetate, an ethylene glycol solution B of polyvinyl pyrrolidone (PVP), an ethylene glycol solution C of water-soluble chloride and concentrated acid D; mixing the components according to a certain amount and fully stirring to form a final mixed solution; moving the final mixed solution into a reaction kettle; placing in an oven for reaction for a certain time; taking the reaction kettle out and cooling to room temperature to obtain mother liquid of the nano-silver wire; adding alcohol into the mother liquid for diluting, and removing supernatant liquor to obtain a precipitate; and repeatedly performing centrifugal separation, and thus obtaining nano-silver wire dispersion liquid uniformly dispersed in the alcohol. The method is simple, high in efficiency and low in cost, and can prepare high-quality nano-silver wires within a wider range of reaction condition; and prepared products are high in length-diameter ratio, good in length uniformity and low in impurity content.

The invention discloses a dopamine-nanosilver composite coating and a preparation method thereof. Firstly, pure titanium or a titanium alloy with titanium dioxide nanotube arrays grown on the surface of the titanium alloy is put in a dopamine buffer solution, then the pure titanium loaded with the dopamine or the titanium alloy with the titanium dioxide nanotube arrays grown on the surface of the titanium alloy is put in a silver nitrate solution, and nanosilver particles are obtained by photoreduction. According to the dopamine-nanosilver composite coating and the preparation method thereof, the chelating property of the dopamine and metal ions and the reducibility in an auto polymerization process are utilized, and the antibacterial performance of material is improved by preparing the nanosilver coating on the surface of the titanium alloy, which has important application value and guiding significance for developing novel functional metal implant material.

A process for preparing the micron-class spherical silver powder used for electrically conductive Ag slurry features that in the redox procedure, the silver nitrate solution is dripped into reducer and disperser while the ammonia water is used to regulate the pH value of solution, and the kind of disperser, stirring speed, and reaction temp and time are regulated.

The invention relates to a method for preparing a length-controlled silicon nanowire array with a smooth surface, and belongs to the technology of the preparation of nanometer materials. The method comprises the following steps of: firstly, performing wet chemical cleaning on a silicon wafer; secondly, depositing a silver nanometer granular layer on the surface of the silicon wafer in mixed solution containing hydrofluoric acid and silver nitrate by an electroless chemical deposition method; thirdly, performing chemical etching by mixed solution containing the hydrofluoric acid and hydrogen peroxide; and finally, removing silver nanometer granules by using nitric acid to obtain the silicon nanowire array. In the method, length-controlled silicon nanowires with the smooth surfaces are prepared by regulating the concentration and etching time of the hydrogen peroxide serving as an oxidant simply in a chemical etch system, so the technical problem of preparing the silicon nanowires with fewer surface defects in metal-assisted chemical etching is solved.

The present invention provides a novel visible catalyst-silver phosphate and a preparation method thereof, solving the problems of wide TiO2 forbidden band, no absorbability of visible weakness, and the like in the prior art and applying Ag3PO4 to the field of photocatalysis for the first time. In the invention, a silver ammonia solution for replacing a silver nitrate solution is used as a silversource, the reaction of silver ions and phosphate ions is slowed, and then the catalyst is obtained and has the effect of high-efficiency photocatalytic degradation. The preparing method of the invention is simple and is favorable to extensive popularization.

The invention relates to a preparation method of high dispersibility superfine silver powder with adjustable grain diameter, comprising the following steps: 1. dissolving silver nitrate and surfactant in water to prepare silver solution A; 2. dissolving ascorbic acid, PH regulator and surfactant in water to prepare reducing liquid B; 3. preparing alkaline aqueous solution C by alkaline PH regulator; dropwise adding alkaline aqueous solution C and silver solution A to reducing liquid B at the set time. PH value of the reducing liquid B and flow velocity of alkaline aqueous solution C are adjusted, so that silver power particle size can be easily adjusted and the silver power particles can grow up uniformly. The silver powder obtained by the method of the invention has the characteristics of polyhedral microcosmic appearance, good dispersibility, narrow size distribution, high tap density and good sintering character.

The invention relates to an antibacterial treatment method for textiles, in particular to a finishing method for nano-silver antibacterial textiles, belonging to the textile after finishing technical field. The method comprises the following steps that: a textile is dipped in a nano-silver aqueous solution for 1-120 min, or a textile carrying amino-terminated overspending compound and quaternary ammonium salt thereof is dipped in a 0.01-0.5 mol / L silver nitrate solution for 1-120 min; after the textile is taken out, washed and air-dried, a nano-silver antibacterial textile is obtained; the nano-silver aqueous solution is obtained by mixing an amino-terminated overspending compound and quaternary ammonium salt aqueous solution having the mass percentage between 0.01 and 5 percent and a silver nitrate solution having the molality between 0.01 and 0.5 mol / L. The treatment method has the advantages of without needing additional dispersant, reductant or adhesive, simple process, convenient operation and excellently antibacterial performance of the obtained nano-silver antibacterial textile.

The invention discloses a cellulose fiber-supported nano silver antibacterial material and a preparation method thereof. The preparation method comprises the steps of: conducting chemical pretreatment on cellulose fibers, then conducting TEMPO (2, 2, 6, 6-tetramethylpiperidine-1-oxyl) selective oxidization on the cellulose fibers, and finally on the premise that not any reducing agent is added, enabling the oxidized cellulose fibers to react with silver nitrate in silver nitrate water solution through a short-time microwave heating method to prepare the cellulose fiber-supported nano silver antibacterial material with small-diameter and even-structure nano silver particles. By adopting the preparation method, on the premise that not any reducing agent is added, in-situ reduction and growth of nano silver on carboxylated cellulose fiber supporters are realized. The prepared cellulose fiber-supported nano silver antibacterial material has the advantages of small nano grain size and even size, and can be widely applied to the fields of antibacterial operation clothes, wound dressing, drug controlled release, textile coating and the like.

The invention relates to a preparation method for high-conductivity graphene and silver nanoparticle composite materials. The method comprises the steps that graphene oxide is prepared at first; a graphene oxide water solution is prepared; silver nitrate is added into the obtained graphene oxide water solution, the temperature is risen to be 90+ / -10 DEG C, sodium citrate is added in the solution, and stirring and reaction are conducted; ammonium hydroxide and hydrazine hydrate are added into the obtained solution, and stirring and reaction are conducted at the temperature of 90+ / -10 DEG C; deionized water and ethyl alcohol are adopted to clean the reaction product, vacuum freeze drying is conducted on the cleaned reaction product, and then the conductive graphene and silver nanoparticle composite materials are obtained. The conductivity of the composite materials is 3.71-18.32S / cm, the graphene and silver nanoparticle composite materials prepared based on the method can greatly improve the conductivity of graphene, and can be further applied in the field of printed electronics.

The invention discloses a washing-free antibacterial hand sanitizer and a preparation method thereof. Raw materials of the washing-free antibacterial hand sanitizer calculated at 100ml include 1-10g of chlorhexidine salt, 5-1,000ug of silver nitrate, 30-90ml of alcohol, 2-50g of skin care agent, 0.5-3g of tackifier, 0.5-3g of surfactant, 0.5-5g of p+H regulator and 15-50ml of deionized water. In the preparation method, the skin care agent and the chlorhexidine salt are added to the alcohol and dissolved under the temperature of 30-70 DEG C to form alcoholic solution; the tackifier, the surfactant and the silver nitrate are added to the deionized water to form aqueous solution; finally, the aqueous solution and the pH regulator are added to the alcoholic solution to prepare the washing-free antibacterial hand sanitizer. The washing-free antibacterial hand sanitizer contains various antibacterial components, has very strong broad-spectrum antibacterial and bactericidal effects on various bacteria and fungi, and has long-acting antibacterial effect.

The invention discloses a titanium alloy containing an antibacterial coating as well as a preparation method and application thereof. The titanium alloy deposited with nano-silver antibacterial coating on the surface is prepared by the following steps: preprocessing and sterilizing the surface of titanium alloy; then soaking the titanium alloy in a dopamine hydrochloride solution with mass-volume concentration of 1-10mg / mL for 12-36h to obtain titanium alloy deposited with a polydopamine thin film layer on the surface; and finally soaking the titanium alloy in a silver nitrate solution which is 5-100mmol / L in concentration for 12-36h. According to the titanium alloy disclosed by the invention, the titanium alloy is connected to silver nanoparticles by virtue of adhesion from self-polymerization of dopamine and adsorbed silver ions are reduced into nano-silver in situ through weak reducibility of the dopamine. Because of broad-spectrum antibacterial capacity of the nano-silver, an excellent antibacterial effect can be achieved with relatively low effect concentration. The invention provides new thinking for antibacterial modification of the titanium alloy, and can effectively promote application of a titanium alloy implant material in the fields of bone tissue repair and regeneration.

A method and composition for effecting necrosis of a tissue lining of a mammalian body cavity, particularly a uterine endometrium, by introducing an applicator comprising a hysteroscope housing a first and a second catheter connected to a catheter into the uterus, distending the uterus by introducing CO2 gas under pressure, delivering a silver nitrate paste to the endometrium through the first catheter and allowing the paste to remain a sufficient amount of time to substantially cauterize the entirety of the tissue lining, particularly the endometrium and delivering an aqueous sodium chloride solution to the uterus through the second catheter thereby neutralizing the silver nitrate and rinsing the uterine cavity.

The invention provides a substrate with surface-enhanced Raman scattering activity and a preparation method thereof, and the method comprises the following steps: the glass base surface is subjected to hydroxylation and amination treatment; catalytic hydrolysis is carried out on ethyl orthosilicate under the alkali condition by taking alcohol as a solvent; Silica microspheres with even size and smooth surface are prepared by an oscillation method; silane coupling agent of which the tail end is provided with amino is assembled on the surface of the silica microspheres; silver sol obtained by reducing sodium borohydride to silver nitrate through oscillation is assembled on the surface of SiO2-NH2NPs, and is diffused in water again after centrifugal separation and washing by distillated water; self assembly is carried out on the silver sol after being placed in SiO2@Ag NPs dispersion for 6-12h; the SERS active substrate is obtained after taking out from water and drying. In the SERS active substrate of the invention, the active particles and the substrate are combined firmly, thus being applicable to detecting unimolecular Raman signals in aqueous solution; the substrate can be used for SERS detection repeatedly, thus improving repeated utilization ratio of the substrate.

The invention discloses a chemical silver plating preparing conducting resin method on the graphite powder surface in the chemical silver plating and micro-electronics connection material technique domain, which comprises the following steps: oxidizing the graphite powder in the air at 600-650DEG C; putting the dispersant, reducer and stabilizing agent in de-ionized water for reduced liquid; adding in graphite powder to stir; putting the silver nitrate in the de-ionized water; adding in ammonia and sodium hydroxide to get argentamine; putting the reduced liquid in the argentamine liquid to finish chemical silver plating on the graphite powder surface; filtering; separating and washing; drying in vacuum to get silver coated graphite powder.

The present invention provides a method for preparing a nano silver-carrying titanium dioxide antiseptic. The aqueous ammonia solution and silver nitrate solution are dropped into the titanium sulfate solution simultaneously with continuous stirring. The final reaction pH is controlled by ammonia water. The titanium and silver are leaded to coprecipitate. The solution is filtered and washed after maturing. Afterwards the powder of nano silver-carrying titanium dioxide antiseptic is prepared by drying and calcining. The titanic acid or metatitanic can also be taken as precursor. The slurry containing 15-25% of recursor is added with silver nitrate solution with a concentration of 20-30gL<-1>, and the phosphoric acid, sulfuric acid or hydrochloric acid is added with a concentration of 10-15mgL<-1>. The solution is reacted, filtered and washed under the temperature of 50-60 DEG C. The solid object is dried, crushed, calcined and cooled, and the power of nano silver-carrying titanium dioxide antiseptic is obtained. The invention uses generating an indissoluble silver salt with a preparing technique of titanium dioxide to obtain the sustained-releasing of silver and color changing prevention. Furthermore the complex of the electron pair and the cavity is avoided. The photocatalysis antimicrobial effect of titanium dioxide is reinforced. The color, luster, granularity and dispersibility of the product can be well controlled.