摘要:
An electrocatalyst for fuel cell applications includes a catalyst support and a noble metal or noble metal-based alloy catalyst supported upon the catalyst support. The catalyst support characteristically includes a Group IV-VI transition metal silicide with or without the mixing of carbon. A fuel cell incorporating the electrocatalyst into the anode and/or cathode is disclosed. Such fuel cell exhibit improved cycling and operating performance.
摘要:
An electrocatalyst for fuel cell applications includes a catalyst support and a noble metal or noble metal-based alloy catalyst supported upon the catalyst support. The catalyst support characteristically includes a Group IV-VI transition metal silicide with or without the mixing of carbon. A fuel cell incorporating the electrocatalyst into the anode and/or cathode is disclosed. Such fuel cell exhibit improved cycling and operating performance.
摘要:
The incorporation of tungsten-containing hydrogen spillover materials into a composite fuel cell anode can be helpful in preserving the carbon catalyst support materials in the fuel cell cathode during periods of hydrogen starvation. Preferred examples of such tungsten-containing hydrogen spillover materials are tungsten oxides and tungsten silicides. These materials, when physically mixed with catalyst-loaded carbon support particles in a composite anode, have shown the ability to promote hydrogen storage in amounts that, during a disruption of hydrogen gas flow, can postpone an anodic potential excursion into the oxygen evolution region for a period of at least several seconds.
摘要:
The incorporation of tungsten-containing hydrogen spillover materials into a composite fuel cell anode can be helpful in preserving the carbon catalyst support materials in the fuel cell cathode during periods of hydrogen starvation. Preferred examples of such tungsten-containing hydrogen spillover materials are tungsten oxides and tungsten silicides. These materials, when physically mixed with catalyst-loaded carbon support particles in a composite anode, have shown the ability to promote hydrogen storage in amounts that, during a disruption of hydrogen gas flow, can postpone an anodic potential excursion into the oxygen evolution region for a period of at least several seconds.
摘要:
A method for evaluating the composition of an MEA for a fuel cell. The method includes soaking the MEA in an unsaturated organic compound for a predetermined period of time, and then allowing the MEA to dry. The method then includes staining the MEA with osmium tetroxide (OsO4) in a closed container. The stained MEA is then encased in an epoxy. Thin sections of the encapsulated MEA are then prepared, and the sections are viewed through a transmission electron microscope. The stained MEA will show dark regions where the ionomer and carbon particles are located and lighter regions that are epoxy filled pores.
摘要:
A method for evaluating the spatial distribution of an ionomer in a fuel cell MEA. The method includes embedding the MEA in an epoxy, and then slicing thin sections from the MEA. The sliced sections are then exposed to a titanium tetrachloride vapor that stains the epoxy. The stained sections are then viewed with, for example, a transmission electron microscope (TEM) where the lighter regions in the TEM image show the ionomer distribution.
摘要:
Films of magnesium mixed with titanium are produced by non-equilibrium alloying processes such as electron beam evaporation of magnesium and titanium ingots in a very low pressure chamber. Such magnesium-titanium films form as single phase solid solutions. Titanium is inherently resistant to corrosion and its admixture with magnesium in solid solution provides a new composition that is less subject to intra-film galvanic corrosion. The magnesium-titanium films also provide relatively hard and strong coatings.
摘要:
Methods of generating hydrogen-containing streams having a minimal concentration of gaseous reactive nitrogen-containing compounds, e.g., ammonia, are provided. Hydrogen storage material systems are also provided that generate such hydrogen-containing streams. A first composition comprising a nitride, a second composition comprising a hydride, and a third composition having a cation selected from the group consisting of: alkali metals, alkaline earth metals, and mixtures thereof are combined together. The hydrogen-containing stream thus generated has a minimal concentration of gaseous reactive nitrogen-containing compounds.
摘要:
The invention provides a method of reversibly producing a source of hydrogen gas comprising mixing together a plurality of hydrogen-containing starting materials; and then heating the mixed materials at a temperature sufficient to release hydrogen. Upon release of hydrogen, there is formed a residue which comprises at least one material different from the starting materials. There is also synergy whereby it is possible to regenerate at least one of the hydrogen-containing starting materials by exposing hydrogen gas to the aforesaid residue.
摘要:
A method of depositing a thin gold coating on bipolar plate substrates for use in fuel cells includes depositing a gold coating onto at least one surface of the bipolar plate substrate followed by annealing the gold coating at a temperature between about 200° C. to 500° C. The annealed gold coating has a reduced porosity in comparison with a coating which has not been annealed, and provides improved corrosion resistance to the underlying metal comprising the bipolar plate.