Maximizing Available Active Hydrogen on FeNi Substitutional Solid-Solution Alloy to Boost Electrosynthesis of Ammonia from Nitrate
Xing Sun1,2,3, Yanzheng He2,3, Mengfan Wang2,3(王梦凡)*, Qiyang Cheng2,3, Yunfei Huan4, Sisi Liu5, Jie Liu5, Tao Qian5, Chenglin Yan2,3,4(晏成林)*, Jianmei Lu1(路建美)*
1College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215006, China
2College of Energy, Key Laboratory of Core Technology of High Specific Energy Battery, Soochow University, Suzhou 215006, China
3Key Materials for Petroleum and Chemical Industry, Soochow University, Suzhou 215006, China
4School of Petrochemical Engineering,Changzhou University, Changzhou 213164, China
5School of Chemistry and Chemical Engineering,Nantong University, Nantong 226019, China
ACS Nano 2025, 19, 8, 8189–8199
Abstract:Electrochemical nitrate reduction reaction (NO3RR) 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 NO3RR, leaving the current system as far from satisfactory. Herein, based on reverse utilization of the Sabatier principle, a series of FexNiy substitutional solid-solution alloys (SSAs) are synthesized to manipulate *H behavior for enhanced NO3RR. 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 NO3RR. As expected, a maximum NH3 yield rate of 31.46 mmol h–1 mg–1 is delivered over the optimized Fe3Ni1–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 NO3RR process is verified by external reflection mode.
Article information: //doi.org/10.1021/acsnano.4c17163
