Electrochemical reduction of nitrate to ammonia via direct eight-electron transfer using a copper–molecular solid catalyst


Ammonia (NH3) is essential for modern agriculture and industry and is a potential energy carrier. NH3 is traditionally synthesized by the Haber–Bosch process at high temperature and pressure. The high-energy input of this process has motivated research into electrochemical NH3 synthesis via nitrogen (N2)–water reactions under ambient conditions. However, the future of this low-cost process is compromised by the low yield rate and poor selectivity, ascribed to the inert N≡N bond and ultralow solubility of N2. Obtaining NH3 directly from non-N2 sources could circumvent these challenges. Here we report the eight-electron direct electroreduction of nitrate to NH3 catalysed by copper-incorporated crystalline 3,4,9,10-perylenetetracarboxylic dianhydride. The catalyst exhibits an NH3 production rate of 436 ± 85 μg h−1 cm−2 and a maximum Faradaic efficiency of 85.9% at −0.4 V versus a reversible hydrogen electrode. This notable performance is achieved by the catalyst regulating the transfer of protons and/or electrons to the copper centres and suppressing hydrogen production.

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Fig. 1: Screening of the element with the highest activity for the selective reduction of NO3 into NH3 when incorporated in PTCDA.
Fig. 2: Electrocatalytic performances of O-Cu–PTCDA.
Fig. 3: Characterization of the structure and composition of O-Cu–PTCDA.
Fig. 4: DFT calculations of the adsorption energy of the reactants and free energy for H2 formation.
Fig. 5: DFT calculations of the possible reaction pathways for NO3 reduction.

Data availability

The authors declare that the data supporting the findings of this study are available in the paper and Supplementary Information. Additional datasets related to this study are available from the corresponding authors on reasonable request. Source data are provided with this paper.


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G.-F.C. thanks the Alexander von Humboldt Foundation for a postdoctoral fellowship. This work was financially supported by the National Natural Science Foundation of China (21536005, 51621001 and 21776099), the Post-Doctoral Innovative Talents Project (BX20190119) and National Key R&D Program (2016YFA0202601). A portion of this work was conducted at Argonne National Laboratory. Argonne National Laboratory is operated for the DOE Office of Science by UChicago Argonne, LLC, under contract no. DE-AC02-06CH11357. Use of the Advanced Photon Source (beamline 9BM), Office of Science user facilities, was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract no. DE-AC02-06CH11357.

Author information




G.-F.C. conducted most of experiments. Y.Y. analysed the microscopic and spectroscopic data. L.M. and T.W. conducted the X-ray absorption measurements. G.-F.C., Y.Y., J.L. and H.W. conceived the idea and designed the experiments. G.-F.C., Y.Y., S.-Y.R., H.J., L.-X.D., J.L. and H.W. analysed the data and interpreted the results. S.-Y.R., H.J. and L.-X.D. participated in discussions and data analysis. J.L. and H.W. supervised the project. G.-F.C. and Y.Y. co-wrote the manuscript. All the authors contributed to discussions and the writing of the manuscript.

Corresponding authors

Correspondence to Jun Lu or Haihui Wang.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–42, Notes 1–7, Supplementary Tables 1–3 and refs. 1–9.

Supplementary Data 1

Replicates data for Supplementary Figs. 2, 5–12, 14 and 36–42.

Source data

Source Data Fig. 1

Experimental source data and DFT calculation source data.

Source Data Fig. 2

Experimental source data.

Source Data Fig. 3

Unprocessed TEM and elemental mapping images and experimental source data.

Source Data Fig. 4

DFT calculations source data

Source Data Fig. 5

DFT calculations source data.

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Chen, G., Yuan, Y., Jiang, H. et al. Electrochemical reduction of nitrate to ammonia via direct eight-electron transfer using a copper–molecular solid catalyst. Nat Energy 5, 605–613 (2020). https://doi.org/10.1038/s41560-020-0654-1

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