Boosting Electrocatalytic Nitrate-to-Ammonia via Tuning of N-Intermediate Adsorption on a Zn-Cu Catalyst

Limin Wu; Jiaqi Feng; Libing Zhang; Shunhan Jia; Xinning Song; Qinggong Zhu; Xinchen Kang; Xueqing Xing; Xiaofu Sun; Buxing Han

doi:10.1002/anie.202307952

Boosting Electrocatalytic Nitrate-to-Ammonia via Tuning of N-Intermediate Adsorption on a Zn-Cu Catalyst

Angew Chem Int Ed Engl. 2023 Oct 23;62(43):e202307952. doi: 10.1002/anie.202307952. Epub 2023 Sep 19.

Authors

Limin Wu^{1

2}, Jiaqi Feng¹, Libing Zhang^{1

2}, Shunhan Jia^{1

2}, Xinning Song^{1

2}, Qinggong Zhu^{1

2}, Xinchen Kang^{1

2}, Xueqing Xing³, Xiaofu Sun^{1

2}, Buxing Han^{1

2

4}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences, Key Laboratory of Colloid and Interface and Thermodynamics, Center for Carbon Neutral Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
² School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
³ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
⁴ Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China.

PMID: 37665252
DOI: 10.1002/anie.202307952

Abstract

The renewable-energy-powered electroreduction of nitrate (NO₃ ^- ) to ammonia (NH₃ ) has garnered significant interest as an eco-friendly and promising substitute for the Haber-Bosch process. However, the sluggish kinetics hinders its application at a large scale. Herein, we first calculated the N-containing species (*NO₃ and *NO₂ ) binding energy and the free energy of the hydrogen evolution reaction over Cu with different metal dopants, and it was shown that Zn was a promising candidate. Based on the theoretical study, we designed and synthesized Zn-doped Cu nanosheets, and the as-prepared catalysts demonstrated excellent performance in NO₃ ^- -to-NH₃ . The maximum Faradaic efficiency (FE) of NH₃ could reach 98.4 % with an outstanding yield rate of 5.8 mol g^-1 h^-1 , which is among the best results up to date. The catalyst also had excellent cycling stability. Meanwhile, it also presented a FE exceeding 90 % across a wide potential range and NO₃ ^- concentration range. Detailed experimental and theoretical studies revealed that the Zn doping could modulate intermediates adsorption strength, enhance NO₂ ^- conversion, change the *NO adsorption configuration to a bridge adsorption, and decrease the energy barrier, leading to the excellent catalytic performance for NO₃ ^- -to-NH₃ .

Keywords: Ammonia Synthesis; Cu Catalyst; Electrocatalysis; Green Chemistry; Nitrate Reduction.

Abstract

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