Fuel cells and fuel cell catalysts incorporating a nanoring support

A fuel cell comprising:

• an electrolyte layer positioned between a fuel electrode and an oxygen electrode, wherein the fuel electrode, the oxygen electrode, or both electrodes comprise a supported catalyst, the supported catalyst comprising:
• a plurality of carbon nanorings, each carbon nanoring comprising a plurality of graphite layers forming an annular wall that defines an interior hole that is at least partially bounded by the annular wall and that contributes to the surface area of the nanoring, each nanoring having an irregularly shaped annular structure and a length that is less than or about equal to an outer diameter of the nanoring, wherein the annular wall is formed from between about 5 and about 50 graphite layers and the outer diameter defined by the annular wall is less than about 100 nm, the carbon nanorings having a BET specific surface area greater than about 120 m2/g;
• and
• a plurality of catalyst nanoparticles supported on the carbon nanorings.

A fuel cell, comprising:

• an electrolyte layer positioned between a fuel electrode and an oxygen electrode, wherein the fuel electrode, the oxygen electrode, or both electrodes comprise a supported catalyst, the supported catalyst comprising:
• a plurality of carbon nanorings, each carbon nanoring being formed from a plurality of graphite layers that form an irregularly shaped annular wall, wherein the nanorings have a specific surface area between about 120 m2/g and 400 m2/g and an average inside diameter defined by an interior hole of between about 0.5 nm to about 90 nm;
• and
• a plurality of catalyst nanoparticles supported on the carbon nanorings,
• wherein the carbon nanorings provide a fuel cell that achieves a maximum power density at a higher current than a fuel cell that includes a carbon black support and does not exhibit mass transfer polarization.