Su Xinhao, Hong Feiyang, Fang Yanjie, Wen Yingke, Shan Bing
Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Zhejiang Key Laboratory of Excited-State Energy Conversion and Energy Storage, Hangzhou, 310058, China.
Angew Chem Int Ed Engl. 2025 Mar 17;64(12):e202422072. doi: 10.1002/anie.202422072. Epub 2024 Dec 19.
Electrosynthesis of ammonia (NH) from nitrate (NO ) using renewable energy holds promise as a supplementary alternative to the Haber-Bosch process for NH production. Most research focuses on tuning the catalytic activity of metal catalysts by modification of the catalyst structures. However, the electrode supports which could influence the catalytic activity have not been well-explored. The state-of-the-art electrocatalysts for NO reduction to NH still exhibit limited energy efficiency at ampere-level current density. Herein, we report a polyaniline-based molecular electrode with Cu catalyst for selective and energy-efficient NO reduction to NH. In the electrode, the polyaniline promotes protonation of the key intermediate formed during NO reduction at Cu, which circumvents the limitation of the Cu catalyst in the efficiency-limiting proton transfer step. The molecular electrode produces NH at a partial current density of 2.7 A cm with an energy efficiency of 62 %, demonstrating much better electrochemical performance than common Cu-based electrocatalysts and indicating the great potential in molecular engineering of electrode supports for selective NO reduction.
利用可再生能源从硝酸盐（NO₃⁻）电合成氨（NH₃）有望成为哈伯-博施法生产NH₃的一种补充替代方法。大多数研究集中于通过修饰催化剂结构来调节金属催化剂的催化活性。然而，可能影响催化活性的电极载体尚未得到充分研究。用于将NO₃⁻还原为NH₃的先进电催化剂在安培级电流密度下仍表现出有限的能量效率。在此，我们报道了一种用于将NO₃⁻选择性且高效地还原为NH₃的含铜催化剂的聚苯胺基分子电极。在该电极中，聚苯胺促进了在铜上NO₃⁻还原过程中形成的关键中间体的质子化，这规避了铜催化剂在限制效率的质子转移步骤中的局限性。该分子电极以2.7 A cm⁻²的分电流密度产生NH₃，能量效率为62%，展示出比普通铜基电催化剂更好的电化学性能，并表明在用于选择性NO₃⁻还原的电极载体分子工程方面具有巨大潜力。
