Abstract: This invention relates to a negative electrode material for lithium-ion batteries comprising silicon and having a chemically treated or coated surface influencing the zeta potential of the surface. The active material consists of particles or particles and wires comprising a core comprising silicon, wherein the particles have a positive zeta potential in an interval between pH 3.5 and 9.5, and preferably between pH 4 and 9.5. The core is either chemically treated with an amino-functional metal oxide, or the core is at least partly covered with OySiHx groups, with 1<x<3, 1?y?3, and x>y, or is covered by adsorbed inorganic nanoparticles or cationic multivalent metal ions or oxides.

Abstract: Compositions having copper flakes coated with silver, where the silver is present as a hermetically closed metal shell around the copper, are described. The hermetically closed metal shell can limit oxidation of copper for at least 365 days at a temperature of less than 100° C. The composition can also contain palladium in an amount of about 1% or less by weight of silver in the shell. Palladium limits the migration of copper from the core flakes to the silver shell at temperatures below 250° C. Methods of manufacturing copper flakes coated can include the steps of treating copper flakes with an acid to form acid treated copper flakes, treating the acid treated copper flakes with a polyamine to form polyamine treated copper flakes, depositing silver on the polyamine treated copper flakes to form copper flakes comprising silver deposits, and depositing silver onto the copper flakes comprising silver deposits.

Abstract: A process for the preparation of an activated polymer particle comprising contacting a polymer particle with at least one polyamine, wherein said polyamine has three or more amino groups, to form a surface treated polymer particle; and applying a catalyst to the surface treated polymer particle to form an activated polymer particle. In some examples, the process can further comprise applying a metal coating to said activated polymer particle to form a metal coated polymer particle.

Abstract: This invention relates to a negative electrode material for lithium-ion batteries comprising silicon and having a chemically treated or coated surface influencing the zeta potential of the surface. The active material consists of particles or particles and wires comprising a core comprising silicon, wherein the particles have a positive zeta potential in an interval between pH 3.5 and 9.5, and preferably between pH 4 and 9.5. The core is either chemically treated with an amino-functional metal oxide, or the core is at least partly covered with OySiHx groups, with 1<x<3, 1?y?3, and x>y, or is covered by adsorbed inorganic nanoparticles or cationic multivalent metal ions or oxides.

Abstract: The present invention is directed to hollow catalyst particles comprising a layered shell structure and to a method of their manufacture. The catalyst particles have the general formula Hcore/PMinner shell/IL/PMouter shell in which Hcore is the hollow core, PMinner shell is a precious metal forming the innermost layer of the shell, IL is an intermediate layer comprising a base metal/precious metal alloy, and PMouter shell is a precious metal forming the outermost layer of the shell. The precious metal is selected from Pt, Ir and Pd and mixtures or alloys thereof, and IL is an intermediate layer comprising a base metal/precious metal alloy wherein the concentration of the base metal changes from the periphery of the hollow core to the outer surface of the intermediate layer. The base metal is selected from Co, Ni, and Cu and mixtures thereof.

Abstract: The present invention is directed to catalyst particles comprising a layered core-shell-shell structure and to a method of their manufacture. The catalyst particles have the general formula BM/IL/PM in which BM is a base metal core (selected from Co, Ni or Cu), PM is a precious metal outer shell (selected from Pt, Ir or Pd) and IL is an intermediate layer comprising a base metal/precious metal alloy with a concentration gradient of base metal to the outside PM layer. The particles of the present invention comprise a core-shell-shell structure and a substantially continuous precious metal shell layer. They find use in various catalytic applications, for example in gas-phase catalysis, in electrocatalysts for fuel cells, in catalytic converters for automobiles and in electronic or medical applications.

Abstract: This invention relates to a negative electrode material for lithium-ion batteries comprising silicon and having a chemically treated or coated surface influencing the zeta potential of the surface. The active material consists of particles or particles and wires comprising a core (11) comprising silicon, wherein the particles have a positive zeta potential in an interval between pH 3.5 and 9.5, and preferably between pH 4 and 9.5. The core is either chemically treated with an amino-functional metal oxide, or the core is at least partly covered with OySiHx groups, with 1<x<3, 1<y<3, and x>y, or is covered by adsorbed inorganic nanoparticles or cationic multivalent metal ions or oxides.

Abstract: The present disclosure relates to a method for making a gold nanoparticle dispersion. The method includes providing a first solution that has gold ions in a liquid medium, adding NTA molecules to the first solution to form a gold nanoparticle dispersion. When the NTA molecules are added to the first solution, the NTA molecules act as a reducing agent to reduce the gold ions to gold atoms, after which the gold atoms nucleate to form gold nanoparticles. The excess NTA molecules then attach to the surface of the gold nanoparticles to stabilize the dispersion. The present disclosure also relates to a dispersion composition that includes a liquid medium, gold nanoparticles dispersed throughout the liquid medium, and NTA molecules directly coating the gold nanoparticles.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: The present invention is directed to catalyst particles comprising a layered core-shell-shell structure and to a method of their manufacture. The catalyst particles have the general formula BM/IL/PM in which BM is a base metal core (selected from Co, Ni or Cu), PM is a precious metal outer shell (selected from Pt, Ir or Pd) and IL is an intermediate layer comprising a base metal/precious metal alloy with a concentration gradient of base metal to the outside PM layer. The particles of the present invention comprise a core-shell-shell structure and a substantially continuous precious metal shell layer. They find use in various catalytic applications, for example in gas-phase catalysis, in electrocatalysts for fuel cells, in catalytic converters for automobiles and in electronic or medical applications.

Abstract: The present invention is directed to hollow catalyst particles comprising a layered shell structure and to a method of their manufacture. The catalyst particles have the general formula Hcore/PMinner shell/IL/PMouter shell in which Hcore is the hollow core, PMinner shell is a precious metal forming the innermost layer of the shell, IL is an intermediate layer comprising a base metal/precious metal alloy, and PMouter shell is a precious metal forming the outermost layer of the shell. The precious metal is selected from Pt, Ir and Pd and mixtures or alloys thereof, and IL is an intermediate layer comprising a base metal/precious metal alloy wherein the concentration of the base metal changes from the periphery of the hollow core to the outer surface of the intermediate layer. The base metal is selected from Co, Ni, and Cu and mixtures thereof.

Abstract: The invention discloses core/shell, type catalyst particles comprising a Mcore/Mshell structure with Mcore=inner particle core and Mshell=outer particle shell, wherein the medium diameter of the catalyst particle (dcore+shell) is in the range of 20 to 100 nm, preferably in the range of 20 to 50 nm. The thickness of the outer shell (tshell) is about 5 to 20% of the diameter of the inner particle core of said catalyst particle, preferably comprising at least 3 atomic layers. The core/shell type catalyst particles, particularly the particles comprising a Pt˜based shell reveal a high specific activity. The catalyst particles are preferably supported on suitable support materials such as carbon black and are used as electrocatalysts for fuel cells.

Abstract: The present invention provides an aqueous solution-based method for producing nano-sized silver platelets, which employs the controlled mixing of a silver ion solution, a reducing solution, and an acidic solution, under suitable conditions. Also provided are the silver platelets produced thereby, and compositions containing the silver platelets.

Abstract: A process for the preparation of an activated polymer particle comprising contacting a polymer particle with at least one polyamine, wherein said polyamine has three or more amino groups, to form a surface treated polymer particle; and applying a catalyst to the surface treated polymer particle to form an activated polymer particle.

Abstract: The present invention is directed to a method for preparing colloidal dispersions of precious metal nanoparticles selected from the group consisting of Pt, Au, Pd, Ag, Rh, Ru and mixtures or alloys thereof, and to a method for isolating such precious metal nanoparticles from these colloidal dispersions. The colloidal dispersions are prepared by reducing suitable precious metal precursor compounds in aqueous alkaline solutions at reaction temperatures between 40 and 70° C. and a pH?12.0 in the presence of polysaccharides with average molecular weights (Mw) in the range of 300,000 to 1,000,000. The precious metal nanoparticles are isolated after decomposing the polysaccharide by heating the colloidal dispersions to temperatures >80° C. The nanoparticles can be used for the manufacture of core/shell-type catalyst materials and for electronic, decorative and medical applications.

Abstract: The present invention provides a method for forming compositions having a plurality of ultra-fine metallic particles, and the metallic composition produced therewith. Also provided is a substrate coated with the plurality of ultra-fine metallic particles obtained in accordance with the method of the present invention.

Abstract: The invention discloses core/shell, type catalyst particles comprising a Mcore/Mshell structure with Mcore=inner particle core and Mshell=outer particle shell, wherein the medium diameter of the catalyst particle (dcore+shell) is in the range of 20 to 100 nm, preferably in the range of 20 to 50 nm. The thickness of the outer shell (tshell) is about 5 to 20% of the diameter of the inner particle core of said catalyst particle, preferably comprising at least 3 atomic layers. The core/shell type catalyst particles, particularly the particles comprising a Pt˜based shell reveal a high specific activity. The catalyst particles are preferably supported on suitable support materials such as carbon black and are used as electrocatalysts for fuel cells.

Abstract: The invention discloses core/shell type catalyst particles comprising a Mcore/Mshell structure with Mcore=inner particle core and Mshell=outer particle shell, wherein the medium diameter of the catalyst particle (dcore+shell) is in the range of 20 to 100 nm, preferably in the range of 20 to 50 nm. The thickness of the outer shell (tshell) is about 5 to 20% of the diameter of the inner particle core of said catalyst particle, preferably comprising at least 3 atomic layers. The core/shell type catalyst particles, particularly the particles comprising a Pt-based shell, reveal a high specific activity. The catalyst particles are preferably supported on suitable support materials such as carbon black and are used as electrocatalysts for fuel cells.

Abstract: The invention discloses core/shell type catalyst particles comprising a Mcore/Mshell structure with Mcore=inner particle core and Mshell?outer particle shell, wherein the medium diameter of the catalyst particle (dcore+shell) is ?20 nm. The thickness of the outer shell (tshell) comprises at least 3 atomic layers. The core/shell type catalyst particles, particularly the particles comprising a Pt-based shell, reveal a high specific activity. The catalyst particles are preferably supported on suitable support materials such as carbon black and are used as electrocatalysts for fuel cells.

Abstract: The invention provides a method for manufacturing supported noble metal based alloy catalysts with a high degree of alloying and a small crystallite size. The method involves using polyol solvents as reaction medium and comprises a two-step reduction process in the presence of a support material. In the first step, the first metal (transition metal; e.g. Co, Cr, Ru) is activated by increasing the reaction temperature to 80 to 160° C. In the second step, the second metal (noble metal; e.g. Pt, Pd, Au) is added and the slurry is heated to the boiling point of the polyol solvent in a range of 160 to 300 ° C. The catalysts manufactured according to the method are used as electrocatalysts for polymer electrolyte membrane fuel cells (PEMFC), direct-methanol fuel cells (DMFC) or as gas phase catalysts for CO oxidation or exhaust gas purification.