Ambient Electrosynthesis of Urea with Nitrate and Carbon Dioxide over Iron-Based Dual-Sites

Jing Geng; Sihan Ji; Meng Jin; Chao Zhang; Min Xu; Guozhong Wang; Changhao Liang; Haimin Zhang

doi:10.1002/anie.202210958

Ambient Electrosynthesis of Urea with Nitrate and Carbon Dioxide over Iron-Based Dual-Sites

Angew Chem Int Ed Engl. 2023 Feb 1;62(6):e202210958. doi: 10.1002/anie.202210958. Epub 2023 Jan 9.

Authors

Jing Geng^{1

2}, Sihan Ji^{1

2}, Meng Jin^{1

2}, Chao Zhang², Min Xu^{1

2}, Guozhong Wang^{1

2}, Changhao Liang^{1

2}, Haimin Zhang^{1

2}

Affiliations

¹ Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, CAS Center for Excellence in Nanoscience, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei, 230031, China.
² University of Science and Technology of China, Hefei, 230026, China.

Abstract

The development of efficient electrocatalysts to generate key *NH₂ and *CO intermediates is crucial for ambient urea electrosynthesis with nitrate (NO₃ ^- ) and carbon dioxide (CO₂ ). Here we report a liquid-phase laser irradiation method to fabricate symbiotic graphitic carbon encapsulated amorphous iron and iron oxide nanoparticles on carbon nanotubes (Fe(a)@C-Fe₃ O₄ /CNTs). Fe(a)@C-Fe₃ O₄ /CNTs exhibits superior electrocatalytic activity toward urea synthesis using NO₃ ^- and CO₂ , affording a urea yield of 1341.3±112.6 μg h^-1 mg_cat ^-1 and a faradic efficiency of 16.5±6.1 % at ambient conditions. Both experimental and theoretical results indicate that the formed Fe(a)@C and Fe₃ O₄ on CNTs provide dual active sites for the adsorption and activation of NO₃ ^- and CO₂ , thus generating key *NH₂ and *CO intermediates with lower energy barriers for urea formation. This work would be helpful for design and development of high-efficiency dual-site electrocatalysts for ambient urea synthesis.

Keywords: Amorphous Fe Nanoparticles; C−N Coupling Reaction; Dual Active Sites; Fe3O4 Nanoparticles; Urea.

Abstract

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