丹麦技术大学Ib Chorkendorff团队报道了氮还原-氢氧化连续流电合成氨。相关研究成果发表在2023年2月17日出版的《科学》。

氨是化肥、药品和精细化学品的关键成分，是理想的无碳燃料。最近，锂介导的氮还原被证明是在环境条件下电化学合成氨的一种有前途的途径。

该文中，研究人员报道了一种配备有25cm²有效面积气体扩散电极的连续流动电解槽，其中氮还原与氢氧化相结合。研究表明，经典催化剂铂对有机电解质中的氢氧化不稳定，但铂-金合金降低了阳极电位，避免了有机电解质的分解。在最佳操作条件下，在1bar时，在6mA/cm²的电流密度下，氨生产的法拉第效率高达61±1%，能量效率为13±1%。

附：英文原文

Title: Continuous-flow electrosynthesis of ammonia by nitrogen reduction and hydrogen oxidation

Author: Xianbiao Fu, Jakob B. Pedersen, Yuanyuan Zhou, Mattia Saccoccio, Shaofeng Li, Rokas Sainas, Katja Li, Suzanne Z. Andersen, Aoni Xu, Niklas H. Deissler, Jon Bjarke Valbk Mygind, Chao Wei, Jakob Kibsgaard, Peter C. K. Vesborg, Jens K. Nrskov, Ib Chorkendorff

Issue&Volume: 2023-02-17

Abstract: Ammonia is a critical component in fertilizers, pharmaceuticals, and fine chemicals and is an ideal, carbon-free fuel. Recently, lithium-mediated nitrogen reduction has proven to be a promising route for electrochemical ammonia synthesis at ambient conditions. In this work, we report a continuous-flow electrolyzer equipped with 25–square centimeter–effective area gas diffusion electrodes wherein nitrogen reduction is coupled with hydrogen oxidation. We show that the classical catalyst platinum is not stable for hydrogen oxidation in the organic electrolyte, but a platinum-gold alloy lowers the anode potential and avoids the decremental decomposition of the organic electrolyte. At optimal operating conditions, we achieve, at 1 bar, a faradaic efficiency for ammonia production of up to 61 ± 1% and an energy efficiency of 13 ± 1% at a current density of 6 milliamperes per square centimeter.

DOI: adf4403

Source: https://www.science.org/doi/10.1126/science.adf4403