Sodium hypophosphite

About: Sodium hypophosphite is a research topic. Over the lifetime, 1695 publications have been published within this topic receiving 15932 citations.

Electroless composite plating method for preparing Ni-Co-P/Si3N4 plating layer on aluminum alloy

Abstract: The invention discloses an electroless composite plating method for preparing a Ni-Co-P/Si3N4 plating layer on an aluminum alloy, which comprises the steps of powder preprocessing, degreasing, weak base corroding, descaling, zinc precipitating, zinc removing, secondary zinc precipitating and chemical membrane plating, and is characterized in that the chemical plating solution comprises the following components: 6-28g/L nickel sulfate serving as a main salt, 6-26g/L of cobaltous sulfate, 28g/L of sodium hypophosphite serving as a reducing agent, 4-12g/L of Si3N4, 15g/L of boric acid serving as a buffer, 10g/L of citric acid serving as a complexing agent, 0.002g/L of thiourea serving as a stabilizer, 0.08g/L of surfactant Cl16S and the like; and the pH value thereof is 5.0-7.0, the temperature thereof is 75-95 DEG C, and the time is 2h. The invention has the advantages of stable plating solution, simple process and the like, can improve plating layer thickness uniformity, increases bonding force, prolongs the plating layer service life, and further promotes the aluminum alloy to be widely applied in fields such as electronic products, automobile industry, aerospace and the like.

Preparation of copper nanoparticles with low sintering temperature

Abstract: This paper describes a simple and convenient method for the preparation of copper nanoparticles in aqueous solution at room temperature The synthesis of copper nanoparticles from different types of copper salt was studied, with hydrazine and sodium hypophosphite as reducing reagent and lactic acid as capping agents The stable copper nanoparticles with diameter less than 10 nm and a narrow size distribution were prepared with copper acetate as the precursor and hydrazine as reducing reagent The obtained copper nanoparticles were capped by the carboxylic acids that can be completely removed at about 200 °C The copper nanoparticles were characterized by TEM, UV-Vis, SEM and XRD Copper films were prepared from the copper nanoparticles by drop coating and sintered at 150 and 200 °C for 60 min in nitrogen

Electroless nickel plating liquid and electroless nickel plating method

Abstract: PROBLEM TO BE SOLVED: To obtain an electroless nickel plating method which imparts a smooth Ni-P film to an Al substrate for hard disks by immersing the substrate into a plating liquid which contains nickel ions, their complexing agents and hypophosphorous acid ions and is added with water-soluble sulfur based additives and water-soluble molybdate and/or tungstate in combination. SOLUTION: The sulfur based additives are one or >=2 kinds selected from thiosulfate (sodium thiosulfate, potassium thiosulfate, etc.), thiocyanate (sodium thiocyanate, potassium thiocyanate, etc.), thiourea and thioacetate. The example of the supply source of the nickel ions includes a water-soluble nickel salt, such as nickel sulfate. One or >=2 kinds of monocarboxylic acid, dicarboxylic acid, tricarboxylic acid and carboxylic acids are used in combination as the complexing agents of the nickel ions. The hypophosphorous acid ions are supplied by sodium hypophosphite, etc. The plating liquid is adequately used for the Al substrate for the hard disks by immersing the substrate into the plating liquid after a zinc substitution treatment.

Preparation method of corrosion-resisting high-conductivity wood electromagnetic shielding material

Abstract: The invention provides a preparation method of a corrosion-resisting high-conductivity wood electromagnetic shielding material, relates to a surface chemical plating method for wood, and aims to solve the technical problem of poor decay resistance of wood on which copper, an Ni-P binary alloy and an Ni-Fe-P ternary alloy are plated in the prior art. The preparation method comprises the following steps: adding nickel sulfate, sodium hypophosphite, sodium citrate, lactic acid, sodium acetate and thiocarbamide into water; stirring to obtain a uniform mixture; adding the pH value of the mixture to be 8 to 10; adding a surfactant and nano alumina; stirring to obtain a uniform plating solution; soaking wood in a 3-aminopropyl triethoxy silane solution; drying the soaked wood; soaking the dried wood into a palladium chloride; soaking with a sodium hypophosphite solution; cleaning; soaking in the plating solution for chemical plating, so as to obtain the corrosion-resisting high-conductivity wood electromagnetic shielding material. The corrosion-resisting high-conductivity wood electromagnetic shielding material is as low as 127.86 [m]Omega/cm , is higher than 45 dB in electromagnetic shielding efficiency, and can be applied to the fields of electronics, aviation and medicine.