Efficient Electrocatalytic Reduction of CO₂to Ethane over Nitrogen-Doped Fe₂O₃

Abstract

Non-copper electrocatalysts are seldom reported to generate C2+ products, and the efficiency over these catalysts is low. In this work, we report a nitrogen-doped γ-Fe2O3 (xFe2O3-N@CN) electrocatalyst, which yield C2H6 as the major product in an H-cell. At −2.0 V vs Ag/Ag+, the Faradaic efficiency (FE) for ethane reaches 42% with a current density of 32 mA cm–2. This is the first report about selective CO2 reduction to ethane (C2H6) over an iron-based catalyst. The results showed that the catalyst possessing FeO1.5–nNn sites enriched with oxygen vacancies was beneficial for the stabilization of *COOH intermediates. The exposure of two adjacent surfaces of Fe atoms was conducive to lowering the energy barrier for C–C coupling over FeO1.5–nNn sites, facilitating the generation of C2H6. This work provides a strategy for the design of a novel iron-based catalyst with tunable local coordination and electronic structures for converting CO2 into C2 products in the CO2RR.