Electrochemical synthesis of ammonia from water and nitrogen: A Fe-mediated approach

• Published in: The Korean journal of chemical engineering Vol. 38; no. 6; pp. 1272 - 1276
• Main Authors: Jeon, Seok Hwan, Kim, Kwiyong, Cho, Hoon, Yoon, Hyung Chul, Han, Jong-In
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2021; Springer Nature B.V; 한국화학공학회
• Subjects: Ammonia; Biotechnology; Catalysis; Catalysts; Chemical synthesis; Chemistry; Chemistry and Materials Science; Deposition; Electrocatalysts; Haber Bosch process; Industrial Chemistry/Chemical Engineering; Iron; Materials Science; Onsite; Room temperature; Solvents; 화학공학; Iron deposition; Ammonia; Electro-synthesis; Nitrogen
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-021-0810-8

Operation at mild conditions is essential for electrochemical processes enough to replace the Haber-Bosch process. Current electrochemical methods mainly rely on the synthesis of novel electro-catalysts before the operation of an electrochemical system, which burdens with extra cost, time, and the use of toxic non-green organic solvents. In this study, the zero-valent iron(Fe 0 )-mediated synthesis of NH 3 was achieved at room temperature, with the active iron prepared in an on-site and continuous way. This on-site approach enabled us to remove the step of cumbersome synthesis of nano-sized electrocatalysts, thereby providing the active surface Fe for nitrogen reduction in eco-friendlier way. When a cell voltage of 4.5 was applied in the two-electrode water-based system, NH 3 was found to be synthesized, which was accompanied by the deposition of Fe on the cathode surface. Considering that iron is among the most abundant and cheapest metals, this room-temperature synthesis proof of the concept with solvent-free, in-situ deposition and its utilization as an electrochemical catalyst, once optimized, may offer an economically advantageous option.