Abstract:
A fuel cell electrode includes a carbon nanofiber substrate and a continuous film of up to 100 atom-thick monolayers forming a network of interconnected electrocatalyst nanoparticles deposited on the carbon nanofiber substrate such that at least some of the nanoparticles are directly adhered to uppermost nanofibers of the substrate to form a layer resistant to electrocatalyst depletion.
Abstract:
An oxygen reduction reaction catalyst (ORR) and a method for making the catalyst are provided. The method may include depositing (e.g., by PVD) conductive catalyst material onto a non-conductive substrate, such as particles or powder, to form an intermediate ORR catalyst. The intermediate ORR catalyst may then be heat treated and another deposition process may be performed to form a thin, electrically interconnected catalyst network layer overlying the non-conductive substrate. The catalyst material may include, for example, platinum, gold, or other platinum group or noble metals, or alloys thereof. The non-conductive substrate may be a ceramic, for example, yttria-stabilized zirconia (YSZ).
Abstract:
In at least one embodiment, a method of forming a platinum thin film is provided, including performing a first atomic layer deposition (ALD) process on a substrate using a first platinum organometallic precursor in a first step and an oxidizing precursor in a second step to form an at least partially coated substrate. A second ALD process is then performed on the at least partially coated substrate using a second platinum organometallic precursor in a first step and a reducing precursor in a second step to form a thin film of platinum on the substrate. The first ALD process may be performed for 5 to 150 cycles to nucleate platinum on the substrate surface and the second ALD process may be performed thereafter to grow the thin film and remove surface oxides. A conformal platinum thin film having a thickness of 1 to 10 monolayers may be deposited.
Abstract:
In at least one embodiment, a method of forming a platinum thin film is provided, including performing a first atomic layer deposition (ALD) process on a substrate using a first platinum organometallic precursor in a first step and an oxidizing precursor in a second step to form an at least partially coated substrate. A second ALD process is then performed on the at least partially coated substrate using a second platinum organometallic precursor in a first step and a reducing precursor in a second step to form a thin film of platinum on the substrate. The first ALD process may be performed for 5 to 150 cycles to nucleate platinum on the substrate surface and the second ALD process may be performed thereafter to grow the thin film and remove surface oxides. A conformal platinum thin film having a thickness of 1 to 10 monolayers may be deposited.
Abstract:
A method of forming a material for reversible hydrogen storage within a storage tank includes charging a mixture of a metal amide and a metal hydride to the storage tank, and chemically reacting the mixture at a reaction condition within the storage tank to form a thermally conducting composite material situated in the storage tank and for reversibly storing hydrogen. The composite material includes a three-dimensional and interconnected framework including a conductive metal. A method for reversibly storing hydrogen includes providing a storage tank and in situ chemically forming a composite material by charging a mixture of a metal amide and a metal hydride to the storage tank and chemically reacting the mixture at a reaction condition to form a thermally conducting composite material including a metal hydride and a substantially unreactive elemental metal framework. Hydrogen is absorbed into the composite material and is desorbed from the composite material.
Abstract:
A bipolar plate for a fuel cell includes an anode plate and a cathode plate. The anode plate has hydrogen flow channels on a first side of the anode plate and coolant channels on a second side of the anode plate. The cathode plate has a first side disposed against the second side of the anode plate to cover the coolant channels and has a second side defining a recessed pocket configured to receive a stream of air. A flow guide is disposed in the pocket such that an inlet manifold is formed along a first edge of the flow guide and an outlet manifold is formed along a second edge of the flow guide. The flow guide defines channels extending from the inlet manifold to the outlet manifold. A plurality of openings is defined by through the flow guide.
Abstract:
A fuel cell oxidation reduction reaction catalyst comprising a carbon substrate, an amorphous metal oxide intermediate layer on the substrate, and an intertwined matrix of platinum and elemental niobium arranged to form a surface metal layer covering the intermediate layer such that upon oxidation, the niobium binds with oxygen resulting in strengthened bonds between the platinum and the intermediate layer.
Abstract:
A fuel cell oxidation reduction reaction catalyst includes a carbon powder substrate, an amorphous conductive metal oxide intermediate layer on the substrate, and a plurality of chained electrocatalyst particle strands bound to the layer to form an interconnected network film thereon having a thickness of up to 10 atom monolayers.
Abstract:
The present disclosure includes a fuel cell bipolar plate including a coating and methods for forming the coating. The bipolar plate may include a steel substrate and a coating contacting the steel substrate. The coating may include a plurality of alternating oxide-forming layers and elution resistant layers. The oxide-forming layers may include pure titanium, doped titanium, or a titanium alloy (e.g. doped/alloyed with niobium, zirconium, vanadium, silver, tantalum, yttrium, scandium, or nitrogen) and the elution resistant layers may include a noble metal or tantalum (e.g., gold, iridium, ruthenium, or tantalum). There may be 2-20 layers each of the oxide-forming layers and the elution resistant layers. The coating may prevent elution of iron ions from the steel substrate, for example, by forming oxide plugs in defects or pinholes in the oxide forming and/or elution resistant layers. The coating may also reduce the total usage of precious metals, such as gold.
Abstract:
A fuel cell oxidation reduction reaction catalyst comprising a carbon substrate, an amorphous metal oxide intermediate layer on the substrate, and an intertwined matrix of platinum and elemental niobium arranged to form a surface metal layer covering the intermediate layer such that upon oxidation, the niobium binds with oxygen resulting in strengthened bonds between the platinum and the intermediate layer.