Efficient Electrocatalytic Reduction of CO2 to 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.