A method of reducing silver(I) salts to silver nanoparticles employing a carbohydrate reductant in the presence of an inorganic base, a surfactant and optionally a polymer. The method is performed in an aqueous solution at a temperature up to 60° C. and for a duration of up to 40 minutes.

The present invention addresses the problem of providing a conductive paste that achieves both low resistance and high adhesion strength (die shear strength) of the resulting conductive body after firing.

The present invention provides a conductive paste comprising: (A) copper fine particles having an average particle diameter of 50 nm to 400 nm and a crystallite diameter of 20 nm to 50 nm; (B) copper particles having an average particle diameter of 0.8 μm to 5 μm and a ratio of a crystallite diameter to the crystallite diameter of the copper particles (A) of 1.0 to 2.0; and (C) a solvent.

The present invention addresses the problem of providing a conductive paste that achieves both low resistance and high adhesion strength (die shear strength) of the resulting conductive body after firing.

The present invention provides a conductive paste comprising: (A) copper fine particles having an average particle diameter of 50 nm to 400 nm and a crystallite diameter of 20 nm to 50 nm; (B) copper particles having an average particle diameter of 0.8 μm to 5 μm and a ratio of a crystallite diameter to the crystallite diameter of the copper particles (A) of 1.0 to 2.0; and (C) a solvent.

The present invention relates to compositions, comprising silver nanoplatelets, wherein the mean diameter of the silver nanoplatelets, present in the composition, is in the range of 20 to 70 nm with standard deviation being less than 50% and the mean thickness of the silver nanoplatelets, present in the composition, is in the range of 5 to 30 nm with standard deviation being less than 50%, wherein the mean aspect ratio of the silver nanoplatelets is higher than 1.5, a process for its production, printing inks containing the compositions and their use in security products. The highest wavelength absorption maximum of the population of all silver nanoplatelets in the composition being within the range of 450 to 550 nm. A coating, comprising the composition, shows a red, or magenta color in transmission and a greenish-metallic color in reflection.

The present disclosure provides a copper nanowire composition. The a copper nanowire composition includes copper nanowire having associated alkylamine ligands with the structure HNR.sup.1R.sup.2. where R.sup.1 and R.sup.2 are independently hydrogen, alkyl or arylalkyl groups. The copper nanowire has an aspect ratio of at least 10. The associated alkylamine ligand is NR.sup.1R.sup.2 which contains at least 12 carbon atoms.

Graphene material-metal nanocomposites having a metal core with one or more graphene material layers disposed on the metal core. The nanocomposites may be formed by contacting metal nanowires and one or more graphene material and/or graphene material precursor in a dispersion. The nanocomposites may be used for form inks for coating or printing conductive elements or as conductors in various articles of manufacture. An article of manufacture may be an electrical device or an electronic device.

The present disclosure is directed to methods of preparing substantially spherical metallic alloyed particles, having micron and sub-micron (i.e., nanometer)-scaled dimensions, and the powders so prepared, as well as articles derived from these powders. In particular embodiments, these metallic alloyed particles, complising rare earth metals, can be prepared in sizes as small 80 nm in diameter with size variances as low as 2-5%.

The invention regards a method for the synthesis of Zero-Valent metal micro- and nanoparticles, in which a first aqueous solution (SOL.sub.1) of a salt of a noble metal (A) is mixed with a third neutral or basic aqueous solution (SOL.sub.3) of an inorganic sulphur-based reducing agent (C), and wherein the mixture thus obtained is added to a second aqueous solution (SOL.sub.2) of a salt of a transition metal (B) and a second aliquot of the inorganic reducing agent; such method provides that the amount of the inorganic reducing agent (C) is in a stoichiometric excess in the reduction reaction to Zero-Valent of both the salt of the noble metal (A) contained in the first solution (SOL.sub.1) and the salt of the transition metal (B) contained in the second solution (SOL.sub.2). The invention also regards Zero-Valent micro and nanoparticles, preferably bimetallic, obtained with the above method. More generally, the invention regards a method for reduction of a transition metal (B) to Zero-Valent metal by an inorganic reducing agent (C), by prior or concurrent reduction of a noble metal (A), wherein the amount of inorganic reducing agent (C) is in stoichiometric excess in the reduction reaction to Zero-Valent of both the noble metal (A) and the transition metal (B). The present invention finds preferred and advantageous application in the remediation and/or the treatment of contaminated water containing at least one polluting substance. The preferred embodiment of the present invention provides that the noble metal (A) is silver, that the transition metal (B) is iron and/or manganese, and the inorganic reducing agent (C) is chosen from borohydrides, dithionites and bisulphites.

Disclosed is a process for producing metal nanowires having a diameter or thickness from 2 nm to 100 nm, the process comprising: (a) preparing a source metal particulate having a size from 50 nm to 500 μm, selected from a transition metal, Al, Be, Mg, Ca, an alloy thereof, a compound thereof, or a combination thereof; (b) depositing a catalytic metal, in the form of nanoparticles or a coating having a diameter or thickness from 1 nm to 100 nm, onto a surface of the source metal particulate to form a catalyst metal-coated metal material, wherein the catalytic metal is different than the source metal material; and (c) exposing the catalyst metal-coated metal material to a high temperature environment, from 100° C. to 2,500° C., for a period of time sufficient to enable a catalytic metal-assisted growth of multiple metal nanowires from the source metal particulate.

A method for producing mesoporous platinum nanoparticles without using templating agents is provided. The method involves preparing a solution comprising water, platinum nanoparticle seeds, a platinum salt and a reducing agent, and heating the solution to a temperature between 150° C. and 250° C. at a rate of between 1° C./min and 15° C./min under a pressure of between 5 and 20 atm. The method allows obtaining mesoporous platinum nanoparticles having controlled shape and controlled pore dimensions. The mesoporous platinum nanoparticles are useful as catalysts in chemical precision reactions and for the production of artificial enzymes for diagnostics and nanomedicine applications.