Liu Mengdi, Ma Yan, Zhang Sai, Chen Min, Wu Limin
Department of Materials Science and State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200433, China.
Adv Sci (Weinh). 2024 Jul;11(28):e2309200. doi: 10.1002/advs.202309200. Epub 2024 May 10.
Electrochemical synthesis of ammonia (NH) in aqueous electrolyte has long been suffered from poor nitrogen (N) supply owing to its low solubility and sluggish diffusion kinetics. Therefore, creating a N rich microenvironment around catalyst surface may potentially improve the efficiency of nitrogen reduction reaction (NRR). Herein, a delicately designed N filtering membrane consisted of polydimethylsiloxane is covered on catalyst surface via superspreading. Because this membrane let the dissolved N molecules be accessible to the catalyst but block excess water, the designed N rich microenvironment over catalyst leads to an optimized Faradaic efficiency of 39.4% and an NH yield rate of 109.2 µg h mg, which is superior to those of the most report metal-based catalysts for electrochemical NRR. This study offers alternative strategy for enhancing NRR performance.
在水性电解质中通过电化学合成氨（NH₃）长期以来一直受到氮（N₂）供应不足的困扰，这是由于其低溶解度和缓慢的扩散动力学。因此，在催化剂表面创造一个富氮微环境可能会提高氮还原反应（NRR）的效率。在此，通过超铺展在催化剂表面覆盖了一层精心设计的由聚二甲基硅氧烷组成的氮过滤膜。由于该膜使溶解的N₂分子能够接触到催化剂，但阻止了过量的水，在催化剂上设计的富氮微环境导致优化的法拉第效率为39.4%，NH₃产率为109.2 μg h⁻¹ mg⁻¹，这优于大多数报道的用于电化学NRR的金属基催化剂。这项研究为提高NRR性能提供了替代策略。
