The dominant Haber–Bosch process to produce ammonia, arguably the most important chemical in support of global food supply, is both energy and carbon intensive, resulting in substantial environmental impacts. Electrocatalytic nitrogen reduction reaction (NRR) powered by renewable electricity provides a green synthetic route for ammonia, but still suffers from insufficient yield rate and Faradaic efficiency. Single-atom electrocatalysts (SACs) have the potential to transform this catalytic process; however, controllable synthesis of SACs with high loading of active sites remains a big challenge. Here we utilize bacterial cellulose with rich oxygen functional groups to anchor iron (Fe) and cobalt (Co), realizing high density, atomically dispersed, bimetallic Fe–Co active sites. For electrocatalytic NRR, our catalyst design delivers a remarkable ammonia yield rate of 579.2 ± 27.8 μg h−1 mgcat.−1 and an exceptional Faradaic efficiency of 79.0 ± 3.8%. The combined theoretical and experimental investigations reveal that the operando change in coordination configuration from [(O-C2)3Fe–Co(O-C2)3] to [(O-C2)3Fe–Co(O-C)C2] is the enabling chemistry. Our findings suggest a general approach to engineer SACs that can drive critical reactions of relevance for sustainability.
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H.Z. acknowledges funding support from the Natural Science Foundation of China (grant no. 52172106 and 51872292). M.H. acknowledges funding support from the Natural Science Foundation of China (grant no. 61804154). Y.L. acknowledges funding support from the Natural Science Foundation of China (grant no. 52122212), Youth Innovation Promotion Association of the CAS (grant no. 2020458) and National Key Research and Development Program of China (grant no. 2019YFA0307900). S.Z. acknowledges funding support from Anhui Provincial Natural Science Foundation (grant no. 2108085QB60), CASHIPS Director’s Fund (grant no. YZJJ2021QN18), China Postdoctoral Science Foundation (grant no. 2020M682057) and Special Research Assistant Program, Chinese Academy of Sciences. This work is also supported by the CAS/SAFEA International Partnership Program for Creative Research Teams of Chinese Academy of Sciences, China. This work was carried out with the support of 1W1B beamline at Beijing Synchrotron Radiation Facility. The computation work was carried out at LvLiang Cloud Computing Centre of China and the DFT calculations were performed on TianHe-2.
The authors declare no competing interests.
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Zhang, S., Han, M., Shi, T. et al. Atomically dispersed bimetallic Fe–Co electrocatalysts for green production of ammonia. Nat Sustain 6, 169–179 (2023). https://doi.org/10.1038/s41893-022-00993-7