Facet Regulation of Fe₂O₃ via Nanoarray Architecture to Enable High Faradic Efficiency for Electrocatalytic Nitrogen Fixation

Abstract

We propose a facile facet regulation enabled by nanoarray architecture to achieve a high faradic efficiency of Fe₂O₃ catalyst for NRR. The α-Fe₂O₃ nanorod arrays (NAs) were directly grown on carbon cloth (CC) with specific (104) facet exposure. The highly exposed (104) facets provide abundant unsaturated Fe atoms with dangling bonds as nitrogen reduction reaction catalytically active sites. In addition, the NAs architecture enables the enhanced electrochemical surface area (ECSA) to fully manifest the active sites and maintain the mass diffusion. Thus, the selectively exposed (104) facets coupled with the high ECSA of NAs architecture achieve a high FE of 14.89% and a high yield rate of 17.28 µg h⁻¹ cm⁻². This work presents an effective strategy to develop highly efficient catalytic electrodes for electrochemical NRR via facet regulation and nanoarray architecture.

Keywords

facet regulation / Fe₂O₃ / nanoarray architecture / nitrogen reduction reaction / faradic efficiency

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