Chen Shanshan, Wang Zhiwei, Zhang Quan, Qiu Shiming, Liu Yifan, Hu Guangzhi, Luo Jun, Liu Xijun
School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
Chongzuo Key Laboratory of Comprehensive Utilization Technology of Manganese Resources, Guangxi Key Laboratory for High-value Utilization of Manganese Resources, college of Chemistry and Biological Engineering, Guangxi minzu normal University, Chongzuo, Guangxi, 532200, China.
Chemistry. 2025 Feb 12;31(9):e202404129. doi: 10.1002/chem.202404129. Epub 2024 Dec 8.
Nitrate reduction reaction (NORR) involves an 8-electron transfer process and competes with the hydrogen evolution reaction process, resulting in lower yields and Faraday efficiency (FE) in the process of NH synthesis. Especially, Cu-based catalysts (Cu and Cu) have been investigated in the field of NORR due to the energy levels of d-orbital and the least unoccupied molecular orbital (LUMO) π* of nitrate's orbital. Based on the above, we synthesized a Cu-based compound containing CuN (Cu) through a simple one-step pyrolysis method, applied it to electrocatalytic NORR, and tested the performance of the Zn-NO battery. Through various characterization analyses, Cu-based catalysts (Cu) are the key active sites in reduction reactions, making CuN a potential catalyst for ammonia synthesis. The research results indicate the application of CuN catalyst in NORR shows the best NH yield of 173.7 μmol h cm with FE reaching 91.0 % at -0.3 V vs. RHE, which is much higher than that of Cu catalyst without N. In addition, the Zn-NO battery based on CuN electrode also exhibits an NH yield of 39.8 μmol h cm 63.0 % FE, and a power density of 2.7 mW cm as well as stable cycling charge-discharge stability for 5 hours. This work guides the application of CuN enhanced regulation of the active site in the electrocatalytic synthesis of NH from NORR.
硝酸盐还原反应（NORR）涉及一个8电子转移过程，并与析氢反应过程竞争，导致在氨合成过程中产率和法拉第效率（FE）较低。特别是，基于铜的催化剂（Cu和Cu）由于d轨道的能级以及硝酸盐轨道的最低未占据分子轨道（LUMO）π*，已在NORR领域得到研究。基于上述情况，我们通过简单的一步热解方法合成了一种含CuN（Cu）的铜基化合物，将其应用于电催化NORR，并测试了Zn-NO电池的性能。通过各种表征分析，铜基催化剂（Cu）是还原反应中的关键活性位点，使得CuN成为一种潜在的氨合成催化剂。研究结果表明，CuN催化剂在NORR中的应用显示出最佳的氨产率为173.7 μmol h cm，在相对于可逆氢电极（RHE）为-0.3 V时FE达到91.0%，这远高于不含N的Cu催化剂。此外，基于CuN电极的Zn-NO电池也表现出39.8 μmol h cm的氨产率、63.0%的FE以及2.7 mW cm的功率密度，并且具有5小时的稳定循环充放电稳定性。这项工作指导了CuN增强活性位点调控在从NORR电催化合成氨中的应用。
