Guo Xiaoxi, Wu Tongwei, Li Hengfeng, Zhang Yanning, Ma Chao, Li Hongmei, Chai Liyuan, Zhao Haitao, Liu Min
Hunan Joint International Research Center for Carbon Dioxide Resource Utilization, State Key Laboratory of Powder Metallurgy, School of Physics, Central South University, Changsha, China.
Precision Medicine Translational Research Center, West China Hospital, Sichuan University, Chengdu, China.
Nat Commun. 2025 Sep 26;16(1):8481. doi: 10.1038/s41467-025-63365-7.
Electrosynthesis of NH from low-concentration NO (NORR) in neutral media offers a sustainable nitrogen fixation strategy but is hindered by weak NO adsorption, slow water dissociation, and sluggish hydrogenation kinetics. Herein, we propose an intriguing strategy that successfully overcomes these limitations through using an electron-donating motif to modulate NO-affinitive catalysts, thereby creating dual active site with synergistic functionality. Specifically, we integrate electron-donating nanoparticles into a Fe single-atom catalyst (Fe), where Fe sites ensure strong NO adsorption, while electron-donating motifs promote water dissociation and NO hydrogenation. In situ X-ray absorption spectroscopy (XAS), in situ attenuated total reflection-infrared spectroscopy (ATR-IR), and theoretical calculations reveal that electron-donating motifs increase Fe site electron density, strengthening NO adsorption. Additionally, these motifs also promote water dissociation, supplying protons to lower the NO hydrogenation barrier. This synergistic interplay enables a cascade reaction mechanism, delivering a remarkable Faradaic efficiency (FE) of 90.3% and a NH yield rate of 709.7 µg h mg under 1.0 vol% NO in neutral media, outperforming pure Fe (NH yield rate: 444.2 µg h mg, FE: 56.6%) and prior to systems operating under high NO concentrations. Notably, the high NH yield of 3207.7 μg h mg is achieved in a membrane electrode assembly (MEA) electrolyzer under a 1.0 vol% NO. This work establishes an inspirational paradigm in NORR by simultaneously enhancing NO adsorption, water dissociation, and hydrogenation kinetics, providing a scalable route for efficient NH electrosynthesis from dilute NO sources.
在中性介质中由低浓度NO进行电合成NH₃（氮氧化物还原反应，NORR）提供了一种可持续的固氮策略，但受到NO吸附较弱、水离解缓慢和氢化动力学迟缓的阻碍。在此，我们提出了一种有趣的策略，通过使用供电子基序来调节NO亲和性催化剂，成功克服了这些限制，从而创建具有协同功能的双活性位点。具体而言，我们将供电子纳米颗粒整合到铁单原子催化剂（Fe）中，其中Fe位点确保NO的强吸附，而供电子基序促进水离解和NO氢化。原位X射线吸收光谱（XAS）、原位衰减全反射红外光谱（ATR-IR）和理论计算表明，供电子基序增加了Fe位点的电子密度，增强了NO吸附。此外，这些基序还促进水离解，提供质子以降低NO氢化势垒。这种协同相互作用实现了级联反应机制，在中性介质中1.0 vol% NO条件下，实现了90.3%的显著法拉第效率（FE）和709.7 μg h⁻¹ mg⁻¹的NH₃产率，优于纯Fe（NH₃产率：444.2 μg h⁻¹ mg⁻¹，FE：56.6%），且优于在高NO浓度下运行的先前系统。值得注意的是，在膜电极组件（MEA）电解槽中，在1.0 vol% NO条件下实现了3207.7 μg h⁻¹ mg⁻¹的高NH₃产率。这项工作通过同时增强NO吸附、水离解和氢化动力学，在NORR中建立了一个鼓舞人心的范例，为从稀NO源高效电合成NH₃提供了一条可扩展的途径。
