Industrial-current Ammonia Synthesis by Polarized Cuprous Cyanamide Coupled to Valorization of Glycerol at 4,000 mA cm<sup>-2</sup>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39981855.
- Also identified by DOI 10.1002/adma.202418451 and PMC identifier 11983258.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The electrocatalytic nitrate reduction (NO<sub>3</sub>RR) holds significance in both NH<sub>3</sub> synthesis and nitrate contamination remediation. However, achieving industrial-scale current and high stability in membrane electrode assembly (MEA) electrolyzer remains challenging due to inherent high full-cell voltage for sluggish NO<sub>3</sub>RR and water oxidation. Here, Cu<sub>2</sub>NCN with positive surface electrostatic potential V<sub>S</sub>(r) is applied as highly efficient NO<sub>3</sub>RR electrocatalysts to achieve industrial-current and low-voltage stable NH<sub>3</sub> production in MEA electrolyzer with coupled anodic glycerol oxidation. This paired electro-refinery (PER) system reaches 4000 mA cm<sup>-2</sup> at 2.52 V and remains stable at industrial-level 1000 mA cm<sup>-2</sup> for 100 h with the NH<sub>3</sub> production rate of 97000 µg<sub>NH3</sub> h<sup>-1</sup> cm<sup>-2</sup> and a Faradaic efficiency of 83%. Theoretical calculations elucidate that the asymmetric and electron-withdrawing [N-C≡N] units enhance polarization and V<sub>S</sub>(r), promoting robust and asymmetric adsorption of NO<sub>3</sub> <sup>*</sup> on Cu<sub>2</sub>NCN to facilitate O-N bond dissociation. A comprehensive techno-economic analysis demonstrates the profitability and commercial viability of this coupled system. Our work opens a new avenue and marks a significant advancement in MEA systems for industrial NH<sub>3</sub> synthesis.