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Abstract
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The slow kinetics of the cathodic oxygen reduction reduction (ORR) remain a significant issue in the development
of polymer electrolyte membrane fuel cells (FCs). In this study, Fe-doped porous BN (p-BN) nanosheet is
proposed as an efficient and noble-metal free electrocatalyst for the ORR process in FCs using first-principles calculations.
The calculated formation energies show that the Fe atom is more stable on the p-BN with a boron vacancy
than one with a nitrogen vacancy. The ORR process on this electrocatalyst begins with the cleavage of the
O O bond of chemisorbed O2, followed by the hydrogenation of the separated O atoms to produce two water
molecules. The rate-determining step in the ORR process is the formation of the second H2O molecule with an energy
barrier of 1.12 eV. As a result, ORR prefers a direct four-electron route on the Fe-doped p-BN catalyst. Our
findings can help in the design and manufacturing of novel electrocatalysts for ORR in FCs.
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