Maximizing Available Active Hydrogen on FeNi Substitutional Solid-Solution Alloy to Boost Electrosynthesis of Ammonia from Nitrate

作者：Xing Sun, Yanzheng He, Mengfan Wang, Qiyang Cheng, Yunfei Huan, Sisi Liu, Jie Liu, Tao Qian, Chenglin Yan, Jianmei Lu · 发表于：ACS Nano · 年份：2025 · DOI：10.1021/acsnano.4c17163 · 被引用次数：83 · 研究领域：Ammonia Synthesis and Nitrogen Reduction、Hydrogen Storage and Materials、Catalytic Processes in Materials Science

Electrochemical nitrate reduction reaction (NO 3 RR) stands out as a promising route for sustainable ammonia synthesis, in which active hydrogen (*H) plays a crucial role in both the deoxygenation and hydrogenation steps. However, the regulation of surface *H is still overlooked, and without intervention, the competing hydrogen evolution reaction is kinetically more favored over the NO 3 RR, leaving the current system as far from satisfactory. Herein, based on reverse utilization of the Sabatier principle, a series of Fe x Ni y substitutional solid-solution alloys (SSAs) are synthesized to manipulate *H behavior for enhanced NO 3 RR. Upon precise optimization of the alloy composition, the d-band center of HER-active Ni shifts toward the Fermi level, endowing the catalyst with strong interaction to *H and greatly prolonging its lifetime, which enables abundant supply to facilitate the NO 3 RR. As expected, a maximum NH 3 yield rate of 31.46 mmol h –1 mg –1 is delivered over the optimized Fe 3 Ni 1 –SSA, which is considerably higher than most of the extensively reported works. Several in situ characterizations are combined to gain in-depth insight. Especially, in situ Fourier transform infrared spectroscopy in internal reflection mode directly observes *H enrichment on the catalyst surface, while the accompanied facilitation of the NO 3 RR process is verified by external reflection mode.