Ru Single Atoms Anchored in Metal Borides Enable Hydrogen Spillover for Superior Electrochemical Ammonia Production
Yuanguo Chen, Haoyun Bai, Jiao Lan, Cheng‐Wei Kao, Feng Xie, Linghu Meng, Jilong Li, Ying‐Rui Lu, Ming Peng, Hui Pan, Yongwen Tan
Abstract
Abstract The electrochemical reduction of nitrate represents a promising and sustainable route for valuable ammonia generation. However, a vital challenge in the nitrate reduction reaction is an insufficient supply of active hydrogen ( * H) and slow kinetics at a low working potential, which result in low production efficiency and high energy consumption. Here, we report the single‐atom Ru‐decorated nanoporous metal borides as a high‐performance electrochemical nitrate reduction electrocatalyst utilizing an atomic‐scale hydrogen spillover effect. Notably, the Ru SA /np‐Ni 3 B exhibits a high NH 3 Faradaic efficiency of 96.2%, an NH 3 yield of 30.4 mg h −1 mg −1 , and an energy efficiency of 39.1% at −0.1 V versus RHE. In situ electrochemical characterizations and theoretical calculations reveal that single‐atom Ru anchored in nanoporous Ni 3 B not only can efficiently dissociate water into * H and simultaneously promote the * H spillover for increasing * H coverage on the surface but also can optimize surface states of Ni 3 B active centers, which synergistically reduces the hydrogenation energy barrier for converting nitrate into valuable ammonia products. A two‐electrode electrolyzer integrating nitrate reduction reaction with furfuryl alcohol oxidation reaction achieves current density of 1 A cm −2 at −1.72 V with 100 h stability, improving the energy efficiency and economy of the system.