415 results about "Palladium alloy" patented technology

The invention relates to platinum-coated particles useful as fuel cell electrocatalysts. The particles are composed of a noble metal or metal alloy core at least partially encapsulated by an atomically thin surface layer of platinum atoms. The invention particularly relates to such particles having a palladium, palladium alloy, gold alloy, or rhenium alloy core encapsulated by an atomic monolayer of platinum. In other embodiments, the invention relates to fuel cells containing these electrocatalysts and methods for generating electrical energy therefrom.

The present invention relates to particle and nanoparticle composites useful as oxygen-reduction electrocatalysts. The particle composites are composed of a palladium or palladium-alloy particle or nanoparticle substrate coated with an atomic submonolayer, monolayer, bilayer, or trilayer of zerovalent platinum atoms. The invention also relates to a catalyst and a fuel cell containing the particle or nanoparticle composites of the invention. The invention additionally includes methods for oxygen reduction and production of electrical energy by using the particle and nanoparticle composites of the invention.

The present invention relates to methods for producing metal-coated palladium or palladium-alloy particles. The method includes contacting hydrogen-absorbed palladium or palladium-alloy particles with one or more metal salts to produce a sub-monoatomic or monoatomic metal- or metal-alloy coating on the surface of the hydrogen-absorbed palladium or palladium-alloy particles. The invention also relates to methods for producing catalysts and methods for producing electrical energy using the metal-coated palladium or palladium-alloy particles of the present invention.

Disclosed herein are a method for plating a printed circuit board and the printed circuit board manufactured therefrom. In the method, a bare soldering or wire bonding portion of a copper (Cu)- or copper alloy layer, is plated with palladium (Pd) or a palladium alloy, and then gold (Au) or a gold alloy is deposited over the palladium or palladium alloy plated layer by an electroless substitution plating process based on ionization tendency. Having superior hardness, ductility and corrosion resistance, palladium is suitable for use between a connector and a substrate and meets requirements for the printed circuit board even when applied to a low thickness, greatly reducing the process time. Accordingly, the problem of black pad, which frequently occur on electroless nickel and electroless gold finish upon surface mount technology, can be perfectly solved. Particularly, fatal bending cracks can be prevented from occurring in the rigid-flexible or flexible printed circuit boards.

The present invention provides an improved implantable medical device comprising at least one portion made of a radiopaque material selected from the group consisting of various palladium alloys, including a palladium alloy having, by weight, rhenium in the range of up to about 20 percent, and preferably rhenium at about 14 percent of the alloy, by weight. The present invention further provides a wire guide, an embolization coil, a marker band, a stent, a filter, an RF ablation coil, and an electrode having at least one portion made of the radiopaque material.

Sensors for determining the ambient amount (e.g., concentration) of a chemical (e.g., molecular hydrogen in a gas or vapor) are disclosed. Preferred embodiments of these sensors comprise a dense thin metal (e.g., palladium or a palladium alloy) film disposed on a microcantilever beam that is suspended above a stationary baseplate. The dense thin metal film is configured to absorb, for example, hydrogen, thereby causing the film to expand which in turn causes the microcantilever beam to deform. The deformation can be measured, for example, as a change in capacitance between the microcantilever beam and the stationary baseplate. The measured change in capacitance is indicative of the ambient hydrogen concentration.

An electrical component is provided by a method comprising forming a middle plated layer made of palladium or a palladium alloy on a substrate and forming a surface plated layer made of tin or a tin alloy containing a metal other than palladium on the middle plated layer. Thus, there can be provided an electrical component having a surface layer consisting primarily of tin in which whisker formation can be prevented for a long period under stress.

A copper-based alloy wire made of a material selected from the group consisting of a copper-gold alloy, a copper-palladium alloy and a copper-gold-palladium alloy is provided. The alloy wire has a polycrystalline structure of a face-centered cubic lattice and consists of a plurality of equi-axial grains. The quantity of grains having annealing twins is 10 percent or more of the total quantity of the grains of the copper-based alloy wire.

The invention discloses a multi-channel metal palladium or a palladium alloy composite membrane hydrogen separator. A graphite sealing ring is adopted to connect and seal the multi-channel metal palladium or the palladium alloy composite membrane and a metal joint at any position in a section of an outer surface membrane. In order to better realize sealing connection, any position in a section where the outer surface and one end have a 3-50mm distance on the adopted multi-channel metal palladium or palladium alloy composite membrane is provided with a groove or a gradient exists along the outer surface membrane and is formed at a position having a 10-80mm distance from the end through concaving, so that the multi-channel metal palladium or the palladium alloy and the metal joint can be insealing connection more closely. The metal joint and a separator shell are connected to form the hydrogen separator. When the metal joint and the separator shell are connected to form the hydrogen separator, at least one metal joint at one end of the two ends is connected with a metal pipe capable of buffering the stress of expansion caused by heat and contraction caused by cold so as to release the stress in the heating and cooling processes. The hydrogen separator has the advantages of obviously low device investment and separation cost for medium and small-scale hydrogen separation.

An improved metal gas separation membrane for separating hydrogen from a gas steam includes a quantity of metal particles that are bonded together to form a porous body that is selectively permeable to hydrogen. The porous body may have a porosity that increases from a first surface to an opposite second surface. The metal gas separation membrane may additionally include a coating of ceramic particles on the first surface thereof to further decrease the porosity at the first surface. Alternatively, or in addition thereto, the metal gas separation membrane may include a thin foil or coating of a dense precious metal such as palladium, palladium-alloys, and the like applied thereto that is permeable by hydrogen according to a chemisorption-dissociation-diffusion transport phenomenon. Still alternatively, or in addition thereto, the porous body may include a catalytic enhancement that can interact with a gas stream to increase the concentration of hydrogen according to various catalytic reactions such as the water gas shift reaction and the ammonia decomposition reaction.

The present invention relates to gas separation membranes including a metal-based layer having sub-micron scale thicknesses. The metal-based layer can be a palladium alloy supported by ceramic layers such as a silicon oxide layer and a silicon nitride layer. By using MEMS, a series of perforations (holes) can be patterned to allow chemical components to access both sides of the metal-based layer. Heaters and temperature sensing devices can also be patterned on the membrane. The present invention also relates to a portable power generation system at a chemical microreactor comprising the gas separation membrane. The invention is also directed to a method for fabricating a gas separation membrane. Due to the ability to make chemical microreactors of very small sizes, a series of reactors can be used in combination on a silicon surface to produce an integrated gas membrane device.

The invention is directed to a method for producing Palladium alloy composite membranes that are useful in applications that involve the need to separate hydrogen from a gas mixture. Further, in one embodiment, a Pd alloy composite membrane is realized in which the Pd alloy film is 1 μm or less in thickness and resistant to poisoning by sulfide compounds. Further, the Pd alloy composite membranes are applied to a number of applications, such a fuel reforming.

The invention relates to an electrocatalyst, in particular to a gold-palladium alloy/carbon nitride composite nanomaterial and a preparing method and application thereof. The preparing method comprises the steps that g-C3N4 powder is weighted and dissolved in purified water, and ultrasonic dispersion is carried out; an HAucl4 solution and an H2Pdcl4 solution are added into the mixture in sequence, magnetic stirring is carried out until the mixture is mixed evenly, and an NaBH4 solution is added in a dropwise mode, magnetic stirring is carried out until the mixture becomes uniform; an oil bath reaction is carried out; after the reaction is finished, the mixture is cooled to the indoor temperature; the gold-palladium alloy/carbon nitride composite nanomaterial is obtained after washing, centrifugal separating and drying are carried out. The composite nanomaterial can be used for electrochemical detection for hydrogen peroxide.

Methods for forming hydrogen sensing materials include forming a palladium alloy thin film having less than about 83 atomic percent of palladium, and annealing the palladium alloy thin film to relieve residual stress and increase atomic intermixing of the nanorystaline lattice, while maintaining a grain size close to the grain size of the nonannealed palladium alloy thin film. For example, the sensing material may include a palladium-gold alloy thin film having about 60 atomic percent of palladium and about 40 atomic percent of gold. The palladium-gold alloy thin film is then annealed at a temperature of about 200 degrees Celsius for 1 hour. Methods for detecting hydrogen containing gas in which the hydrogen sensing material is maintained in a single phase when exposed to the hydrogen containing gas, and optical hydrogen sensors are also disclosed.

The present invention discloses a palladium alloy catalyst, a preparation method and applications thereof, wherein the palladium alloy catalyst is alloy nanoparticles formed from a palladium element and a base metal element, and the surface of the alloy nanoparticles has a porous structure. According to the present invention, by introducing the base metal into the palladium metal, the palladium metal content is effectively reduced, the economic cost of the palladium alloy catalyst is effectively reduced, the palladium metal provides the synergistic effect with the base metal, and the palladium alloy catalyst can have high catalytic activity and high stability through the porous structure on the surface; and with the method, the advantages of effectively-reduced catalyst production cost, energy source saving, environment protection and mass-production can be provided.

A reactor/purifier for generating pure hydrogen in a stack or array of pairs of alternatingly connected high and low pressure reactor chambers wherein a gas-porous turbulence-promoting screen structure washcoated with a steam-reforming catalyst is sandwiched between a planar hydrogen-selective palladium alloy membrane and a planar gas-impermeable heat-conducting metal plate within the high pressure reactor chamber of each high pressure reactor chamber; and wherein the catalyst-coated structure in each high pressure chamber is reacted with steam and hydrocarbon fuel, such as methane or syn/gas, and/or carbon monoxide at an appropriately controlled temperature of between about 200° C. to 650° C. to produce hydrogen and carbon oxides within an isothermal temperature range in each high pressure reactor chamber, while simultaneously permeating pure hydrogen therefrom through the membrane into the corresponding connected low pressure reactor chamber, and with the required heat transfer to and from the catalyst being provided in situ predominantly by conduction through the corresponding metal plate.

The present invention aims to provide a plated terminal for connector which requires a smaller insertion force by reducing a friction coefficient and a terminal pair formed using such a plated terminal for connector. An alloy containing layer (1) made of tin and palladium and containing a tin-palladium alloy is formed on a surface of a terminal base material (2) made of copper or copper alloy. Here, the alloy containing layer (1) is preferably such that domain structures of a first metal phase (11) made of an alloy of tin and palladium are formed in a second metal phase (12) made of pure tin or an alloy having a higher ratio of tin to palladium than in the first metal phase (11).