Electrocatalytically Active Fe‐(O‐C₂)₄ Single‐Atom Sites for Efficient Reduction of Nitrogen to Ammonia

Abstract

Single‐atom catalysts have demonstrated their superiority over other types of catalysts for various reactions. However, the reported nitrogen reduction reaction single‐atom electrocatalysts for the nitrogen reduction reaction exclusively utilize metal–nitrogen or metal–carbon coordination configurations as catalytic active sites. Here, we report a Fe single‐atom electrocatalyst supported on low‐cost, nitrogen‐free lignocellulose‐derived carbon. The extended X‐ray absorption fine structure spectra confirm that Fe atoms are anchored to the support via the Fe‐(O‐C2)4 coordination configuration. Density functional theory calculations identify Fe‐(O‐C2)4 as the active site for the nitrogen reduction reaction. An electrode consisting of the electrocatalyst loaded on carbon cloth can afford a NH3 yield rate and faradaic efficiency of 32.1 μg h−1 mgcat.−1 (5350 μg h−1 mgFe−1) and 29.3 %, respectively. An exceptional NH3 yield rate of 307.7 μg h−1 mgcat.−1 (51 283 μg h−1 mgFe−1) with a near record faradaic efficiency of 51.0 % can be achieved with the electrocatalyst immobilized on a glassy carbon electrode.

Boosting Selective Nitrogen Reduction via Geometric Coordination Engineering on Single‐Tungsten‐Atom Catalysts

“…[ 17 ] Therefore, there is an urgent need to explore new catalytically active configurations for inducing superior activities to achieve distinctive electrocatalysis performance. [ 18 ] However, due to the limitation of synthetic approaches and the immaturity of atomic‐scale control technology, it is difficult to engineer the targeted SACs and adjustable structure. [ 19 ] Besides, difficulties in judging the accurate coordination environment and active sites is not conducive to rationalize structure and performance relationship.…”

Metal–Sulfur Linkages Achieved by Organic Tethering of Ruthenium Nanocrystals for Enhanced Electrochemical Nitrogen Reduction

“…Owing to its high gravimetric hydrogen content and energy density, it is also considered as a promising hydrogen carrier. [1,2] The Haber-Bosch (HB) process has been producing NH 3 for more than 100 years, which consumes energy and emits carbon dioxide in vast amounts. Therefore, it is highly desirable to develop a clean, facile, and sustainable alternative to this process.…”

Synthesis Strategies, Catalytic Applications, and Performance Regulation of Single‐Atom Catalysts

“…The electrochemical N 2 reduction reaction (NRR) has served as an environmentally friendly and low‐cost approach by converting renewable energy source into NH 3 under ambient temperature and pressure. [ 130–132 ] The proposed reaction mechanism of N 2 reduction to NH 3 is usually classified into two kinds: 1) dissociative and 2) associative. [ 133 ] Considering the fierce competition between NRR and HER, most of the electrocatalysts exhibit poor yields and FE for industrialization.…”