Enhanced activity and durability of the oxygen reduction catalysts supported on the surface expanded tubular-type carbon nanofiber

•Temperature sensitive tubular type carbon nanofibers (TCNF) are synthesized via CVD method.•Graphitization and further surface modification of the TCNF are performed to apply as a support material.•The Pt catalyst on the surface expanded TCNF for oxygen reduction is discussed with their enhanced catalytic activity and durability.

Tubular type carbon nanofibers (TCNFs) are prepared and used as a catalyst support material for a cathode electrode of low temperature fuel cells through structural modification. The pristine TCNF is treated by graphitization and makes partially torn-tube shape through the surface expansion by rapid thermal treatment of the oxidized graphitized TCNF. Physical properties of the TCNF group are examined, and it is confirmed that the unique ripped texture along fiber axis with graphitic structure is obtained by the surface expansion. Platinum catalysts supported on these TCNF group are prepared and evaluated. Electrochemical properties are examined via cyclic voltammograms and polarization curves for oxygen reduction reaction activity. The platinum catalyst on the surface expanded TCNF has the enhanced activity at initial and the stable performance even after accelerated durability test due to their unique structure.

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