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DOE OSTI · 1859742

Tunable Oxygen Reduction Electrocatalysis by Phenazine-Modified Carbons (Final Report)

Surendranath, Yogesh
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Abstract

This project aims to systematically investigate the fundamental interfacial chemistry that underlies the four-electron, four-proton oxygen reduction reaction (ORR) mediated by heteroatom-doped graphitic carbon electrodes. Heteroatom-doped (Fe, N, etc.) graphitic carbons have emerged as a rich class of materials that are promising ORR catalysts in low temperature fuel cells because of their earth-abundant elements, extremely low cost, environmental harmlessness, and high tolerance to impurities in the fuel stream. However, despite decades of research, systematic efforts to improve the activity, selectivity, and durability of these catalysts has been hampered both by a complex heterogeneous distribution of potential N- and Fe-dopant active sites and by the inability to tune the local electronic structure and environment of the active site with molecular precision. Understanding the fundamental chemistry that influences the turnover-limiting and selectivity determining steps for ORR and other multielectron/multiproton electrocatalytic transformations requires new and innovative methods to prepare heteroatom active sites with molecular precision on carbon surfaces.

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Surendranath, Yogesh. 2022-04-21. Tunable Oxygen Reduction Electrocatalysis by Phenazine-Modified Carbons (Final Report). https://doi.org/10.2172/1859742

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