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Durability enhancement of intermetallics electrocatalysts via N-anchor effect for fuel cells.

ABSTRACT: Insufficient durability and catalytic activity of oxygen reduction reaction (ORR) electrocatalyst are key issues that have to be solved for the practical application of low temperature fuel cell. This paper introduces a new catalyst design strategy using N-anchor to promote the corrosion resistance of electrocatalyst. The as-synthesized N-Pt3Fe1/C shows a high electrocatalytic activity and a superior durability towards ORR. The kinetic current density of N-Pt3Fe1/C as normalized by ECSA is still as high as 0.145?mA cm(-2) and only 7% loss after 20,000 potential cycles from 0.6 to 1.2?V (vs. NHE) in O2-bubbling perchloric acid solution, whereas Pt3Fe1/C shows 49% loss under the same tests. The N-anchor approach offers novel opportunities for the development of ORR catalyst with excellent electrochemical properties.

SUBMITTER: Li X

PROVIDER: S-EPMC3831193 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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