Sodium hypophosphite

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

Stable chemical nickel-plating plating solution and preparation method thereof

Abstract: The invention discloses a stable chemical nickel-plating plating solution and a preparation method thereof. The plating solution comprises following substances per liter: 3-10g of succinic acid, 20-25g of sodium acetate, 8-20ml of lactic acid, 4-16g of citric acid, 1-7ml of propanoic acid, 8-20g of malic acid, 30-35g of sodium hypophosphite, 30-35g of nickel sulfate and 1-9mg of aminothiourea. The preparation method comprises steps of dissolving succinic acid and sodium acetate in water, adding lactic acid, using sodium carbonate to adjust pH=3-4 of solution, then adding citric acid, propanoic acid, malic acid, sodium hypophosphite, nickel sulfate and aminothiourea, at last using sodium carbonate to adjust pH=3.8-4.1 of solution. Compared with the prior art, the plating solution has high stability with no chlorine when using, and high tolerance.

Electroless copper plating solution and method for electroless copper plating

Abstract: An electroless copper plating solution, characterized in that hypophosphorous acid or a hypophosphite is used as a second reducing agent together with a first reducing agent and that a stabilizing agent for suppressing the precipitation of copper is used simultaneously. First reducing agents include formalin and glyoxylic acid, and hypophosphites include sodium hypophosphite, potassium hypophosphite and ammonium hypophosphite. Stabilizing agent for suppressing the precipitation of copper include 2, 2’-bipylidyl, imidazole, nicotinic acid, thiourea, 2-mercaptobenzothiazole, sodium cyanide and thioglycolic acid. The electroless copper plating solution allows the uniform plating at a reduced temperature, in an electroless copper plating on a mirror surface, such as a semiconductor wafer, or the like, which is less susceptible to a plating reaction.

Chemical nickeling ageing liquid recovering and process technology

Abstract: This invention relates to recovery treatment process for nickel-plating liquid. The method contains steps of: (1), regulating pH value to up to 11.5 of the after-used nickel-plating liquid by using solid alkali; (2), adding 2%-5% of the volume, of the plating liquid of sodium hypophosphite and 50-1000ml potassium chlorite with the concentration of 0.03-5g/L; (3), heating the mixed liquid to 40-60 deg.C, and then keeping the temperature; (4), putting a nickel plate or a stainless steel plate with its area of 100 square dm and aerating to accelerate the decomposition. After a certain reaction period the liquid is filtered, recovering metal nickel, treating the filtrate by ion-exchane resin for removing heavy metals, the water is then pumped for reuse or discharged. In this invented treatment of after-used nickel-plating solution, the great part of metal nickel is recovered, with no production of waste residue, no pollution to environment.

PREPARATION AND CHARACTERIZATION OF ELECTROLESS Ni COATING ON THE SURFACE OF MgO WITH POROUS STRUCTURE

Abstract: Generally,the surface pretreatments such as sensitization and activation are necessary for depositing a nickel metal layer on oxide surface by electroless plating,however,for an oxide surface with porous structure it is possible that the pretreatment is not necessary.In this paper,only by use of the surface activity of porous structure,an electroless plated nickel layer can be prepared on the surface of microarc-oxidation-fabricated porous magnesium oxide film in a conventional electroless nickel plating solution,consisted of nickel sulfate as main salt and sodium hypophosphite as reducing agent.Furthermore,the phase,microstructure,electrical conductivity and corrosion resistance of the obtained nickel layer were characterized.The results indicate that the 5μm-thick nickel layer is composed of fine and homogeneously distributed nickel particles,at the same time the microstructure of nickel layer is dense.Nickel layer spreads into the micropores on the surface of porous magnesium oxide film,so that an interleaving interface is formed at nickel/oxide interface.XRD results reveal that the nickel layer contains crystalline Ni and amorphous Ni-P.Four-point probe measurement indicates that the nickel layer exhibits well electrical conductivity.Meanwhile,polarization curve reveals that corrosion potential elevates notably due to the presence of nickel layer.During electroless nickel plating the nickel ions in solution were reduced and deposited in the micropores of porous magnesium oxide film under the action of reducing agent ions,so as to generate tiny primary nickel particles, subsequently,these primary nickel particles continuously grew and spread,and finally formed an entire nickel layer on oxide surface.

Ni-Co-P/cenosphere magnetic composite material and preparation method thereof

Abstract: The invention discloses a Ni-Fe-P/cenosphere magnetic composite material and a preparation method thereof. In the composite material, cenospheres serve as carriers; and Ni-Fe-P films are loaded on the surfaces of the cenospheres. The preparation method comprises the following steps of: performing ultrasonic washing on fly ash cenospheres in the solution of nitric acid; adding the fly ash cenospheres into a mixed solvent of coupling agent-containing ethanol and water; filtering and washing after reacting; adding the cenospheres into the solution of silver nitrate after drying; simultaneously adding the solution of potassium sodium tartrate; stirring to activate the cenospheres; after filtering, washing, drying, adding the cenospheres into the solution of sodium hypophosphite; stirring at room temperature; preparing chemical plating solution; adding ammonia water dropwise to regulate a pH value; adding the plating solution into the solution which contains the cenospheres; filtering, washing and drying after reacting with stirring; and obtaining the Ni-Fe-P/cenosphere magnetic composite material. The prepared Ni-Fe-P/cenosphere magnetic composite material has the characteristics of a soft magnetic material, and a very good application prospect in the fields such as microwave absorption, electromagnetic shielding, conductive filers, catalysis and the like.