The selective transformation of nitrogen compounds is a foundation of the modern chemical industry. Existing thermochemical processes largely rely on fossil fuels and innovating electrocatalytic processes that could use renewable energy remains challenging. Here we report the electrochemical regulation of a nitrite reduction network using a molybdenum sulfide catalyst by modulating the thermodynamic driving force of proton and electron transfer. The strategy behind this approach is based on the theory of sequential proton–electron transfer, in which the driving force of proton and electron transfer can be optimized independently. This makes it possible to target the desired reactions with selectivities of up to 80% for NO, 61% for N2O, 36% for N2 and 100% for NH4+, comparable to the highest values reported to date using a specific catalyst optimized for a single target product. Consistency with numerical simulation highlights that sequential proton–electron transfer can be used to rationally regulate the electrochemical nitrogen network.
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The data that support the findings of this study are available from the corresponding authors upon request. The Python program for numerical simulations can be found at GitHub (https://github.com/HideshiOoka/SI_for_Publications).
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We thank H. Ofuchi at SPring-8 for his assistance with the XAFS measurements. R.N. was supported by a JSPS Grant-in-Aid for Scientific Research (number 26288092). H.O. was supported by Fusion Oriented Research for Disruptive Science and Technology program of Japan Science and Technology Agency (JST). Y.L. was supported by a JSPS Grant-in-Aid for Scientific Research (number 19K15671). N.Y. and S.T. were supported by a JSPS Kiban-S Grant-in-Aid (number 17H06105). S.H.K. was supported by the Creative Materials Discovery Program (NRF-2017M3D1A1039380). The synchrotron radiation experiments were performed at the BL14B2 of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (proposal numbers 2021A1664, 2021B1920, 2022A1045 and 2022A1669).
The authors declare no competing interests.
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Supplementary Figs. 1–24, Tables 1–10, note 1 and references
Supplementary Data 1
The code for numerical simulation of the Faradaic efficiency.
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He, D., Ooka, H., Li, Y. et al. Regulation of the electrocatalytic nitrogen cycle based on sequential proton–electron transfer. Nat Catal 5, 798–806 (2022). https://doi.org/10.1038/s41929-022-00833-z