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Nano conductive ceramic wedged graphene composites as highly efficient metal supports for oxygen reduction.

ABSTRACT: A novel conductive ceramic/graphene nanocomposite is prepared to prohibit the re-stacking of reduced graphene oxide (RGO) by wedging zirconium diboride (ZrB2) nanoparticles (NPs) into multiple layer nanosheets using a simple solvothermal method. Surprisingly, the RGO/ZrB2 nanocomposite supported Pt NPs shows very excellent catalytic activity. Its electrochemical surface area (ECSA) is up to 148 m(2)g(-1) (very approaches the geometry surface area of 155 m(2)g(-1)), much greater than that of the previous report (usually less than 100 m(2)g(-1)). The mass activity is as high as 16.8 A/g(-1), which is almost 2 times and 5 times that of Pt/RGO (8.6 A/g(-1)) and Pt/C (3.2 A/g(-1)), respectively, as benchmarks. Moreover, after 4000 cycles the catalyst shows only 61% of ECSA loss, meaning a predominantly electrochemical stability. The remarkably improved electrochemical properties with much high Pt utilization of the new catalyst show a promising application in low temperature fuel cells and broader fields.

SUBMITTER: Wu P

PROVIDER: S-EPMC3913918 | biostudies-literature |

REPOSITORIES: biostudies-literature

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