Abstract:
A membrane electrode assembly is provided which includes an anode,- a cathode; a membrane between the anode and the cathode; and a protective layer between the membrane and at least one electrode of the anode and the cathode, the protective layer having a layer of ionomer material containing a catalyst, the layer having a porosity of between 0 and 10%, an ionomer content of between 50 and 80% vol., a catalyst content of between 10 and 50% vol., and an electrical connectivity between catalyst particles of between 35 and 75%. A configuration using a precipitation layer to prevent migration of catalyst ions is also provided.
Abstract:
A method of forming a supported catalyst for a fuel cell includes depositing platinum onto a carbon support material, depositing a first alloy metal onto the carbon support material following the deposition of the platinum, and depositing a second alloy metal onto the carbon support material following the deposition of the first alloy metal. The first alloy metal is selected from iridium, rhodium, palladium, and combinations thereof, and the second alloy metal includes a first or second row transition metal.
Abstract:
Fuel cells (9) include unitized electrode assemblies (12) having a non- perfluorinated hydrocarbon ionomer exchange membrane (26) with anode and cathode catalysts (27, 28) disposed on opposite sides thereof. Adjacent the catalysts, respective optional sublayers (29, 30) may be supported by corresponding gas diffusion layers (31, 32), with adjacent porous, hydrophilic, water transferring reactant gas flow field plates (13, 14) having respective fuel (17) and oxidant (23) reactant gas flow field channels. Water channels (18, 19, 20) hydrate the membrane (26), clear the product water from the cathode (28, 30, 32), flush peroxide radicals, and may also cool the fuel cells. Improved performance (124) (higher voltage at higher current densities) is achieved along with elimination of a propensity for degradation from peroxide decomposition products resulting from oxygen solubility of perfluorinated membranes. Platinum/ruthenium alloy anode catalysts improve performance without degradation which occurs with perfluorinated membranes.
Abstract:
A nanoparticle includes a noble metal skeletal structure. The noble metal skeletal structure is formed as an atomically thin layer of noble metal atoms that has a hollow center.
Abstract:
A method for treating a supported catalyst includes establishing shell-removal conditions for a supported catalyst that includes nanoparticles of a catalyst material on a carbon support. The nanoparticles each include a platinum alloy core capped in an organic shell. The shell-removal conditions include an elevated temperature and an inert gas atmosphere that is substantially free of oxygen. The organic shell is then removed from the platinum alloy core in the shell-removal conditions.
Abstract:
A catalyst support for an electrochemical system includes a high surface area refractory material core structure and boron-doped diamond. The BDD modifies the high surface area refractory material core structure.
Abstract:
A supported catalyst includes a plurality of support particles that each include a carbon support and a layer disposed around the carbon support. The layer is selected from a metal carbide, metal oxycarbide, and combinations thereof. A catalytic material is disposed on the layers of the support particles.
Abstract:
A supported catalyst is prepared by a process that includes establishing shell-removal conditions for a supported catalyst intermediate that includes capped nanoparticles of a catalyst material dispersed on a carbon support. The capped nanoparticles each include a platinum alloy core capped in an organic shell. The shell-removal conditions include an elevated temperature and an inert gas atmosphere that is substantially free of oxygen. The organic shell is removed from the platinum alloy core under the shell-removal conditions to limit thermal decomposition of the carbon support and thereby limit agglomeration of the catalyst material such that the supported catalyst includes an electrochemical surface area of at least 30 m 2 /g Pt .
Abstract translation:载体催化剂通过包括建立负载催化剂中间体的壳去除条件的方法制备,所述载体催化剂中间体包括分散在碳载体上的催化剂材料的封端纳米颗粒。 封盖的纳米颗粒各自包括封装在有机壳中的铂合金芯。 脱壳条件包括升高的温度和基本上不含氧的惰性气体气氛。 在除壳条件下从铂合金芯中除去有机壳以限制碳载体的热分解,从而限制催化剂材料的附聚,使得负载催化剂包括至少30m 2 / g Pt的电化学表面积 。
Abstract:
A fuel cell catalyst support includes a fluoride-doped metal oxide/phosphate support structure and a catalyst layer, supported on such fluoride-doped support structure. In one example, the support structure is a sub-stechiometric titanium oxide and/or indium-tin oxide (ITO) partially coated or mixed with a fluoride-doped metal oxide or metal phosphate. In another example, the support structure is fluoride-doped and mixed with at least one of low surface carbon, boron-doped diamond, carbides, borides, and silicides.
Abstract:
An ion exchange membrane (52) for a fuel cell comprises a polymer having an acid functional group normally including protons, and having alkali metal ions partially ion-exchanged with the protons of the acid functional group of the membrane. The partial ion exchange of alkali metal ions into the membrane relates either to patterning of the exchanged ion make-up of the membrane, with some being ion exchanged and some not, or to the extent or concentration of the ion exchange in any particular location, or to both.