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Vernstrom, George D.

Publications and source records attributed to Vernstrom, George D..

Fuel cell nanocatalyst with voltage reversal tolerance

In some embodiments, the present disclosure provides a fuel cell catalyst having a catalyst surface bearing a non-occluding layer of iridium. In some embodiments, the present disclosure provides a fuel cell catalyst comprising a catalyst surface bearing a sub-monolayer of iridium. In some embodiments, the present disclosure provides a fuel cell catalyst comprising a catalyst surface bearing a layer of iridium having a planar equivalent thickness of between 1 and 100 Angstroms. In some embodiments, the fuel cell catalyst comprises nanostructured elements comprising microstructured support whiskers bearing a thin film of nanoscopic catalyst particles. The layer of iridium typically has a planar equivalent thickness of between 1 and 100 Angstroms and more typically between 5 and 60 Angstroms. The fuel cell catalyst typically comprises no electrically conductive carbon material and typically comprises at least a portion of the iridium in the zero oxidation state.

30 DIRECT ENERGY CONVERSION↗

Platinum nickel catalyst alloy

A Pt--Ni catalyst is provided which demonstrates an unusually high oxygen reduction mass activity. In some embodiments, the Pt--Ni catalyst is a Pt--Ni binary alloy. In some embodiments, the catalyst may be characterized as having a Pt fcc lattice parameter of less than 3.71 Angstroms or 0.371 nm. In some embodiments the catalyst has a Pt fcc lattice parameter of between 3.69 Angstroms (or 0.369 nm) and 3.73 Angstroms (or 0.373 nm). In some embodiments, the catalyst may be characterized as having a composition of close to Pt.sub.xNi.sub.(1-x), where x is between 0.2 and 0.4. In some embodiments the catalyst comprises nanostructured elements comprising microstructured support whiskers bearing a thin film of nanoscopic catalyst particles comprising a catalyst material described above. The catalyst may be particularly useful as a fuel cell catalyst and more specifically as a fuel cell cathode catalyst.

Debe, Mark K.↗

Fuel cell catalyst

A method is provided for making a supported catalyst comprising nanostructured elements which comprise microstructured support whiskers bearing nanoscopic catalyst particles, where the method comprises step a) of vacuum deposition of material from at least a first carbon target in the presence of nitrogen and step b) of vacuum deposition of material from a second target comprising at least one transition metal, the second target comprising no precious metals. In one embodiment, step a) is carried out prior to step b). In another embodiment, steps a) and b) are carried out simultaneously. Typically the deposition steps are carried out in the absence of oxygen. Typically, the transition metal is iron or cobalt, and most typically iron. The present disclosure also provides a supported catalyst comprising nanostructured elements which comprise microstructured support whiskers bearing nanoscopic catalyst particles made according to the present method. The present disclosure also provides a fuel cell membrane electrode assembly comprising the present supported catalyst.

36 MATERIALS SCIENCE↗